Water Journal March 1976

!1ssN 0310 - 0357 j Official Journal of the AUSTRALIAN WATER AND WASTEWATER ASSOCIATION !vol. 3 No. 1, March 1976

Price $1.ool

Problem: How to ensure the efficient handling of your sewerage design & construction.

Solution: Contact the one-stop spot for integrated sewerage pipe systems, house drains to outfall.

I

I

'

'

\

\

Contact Humes.

From large diameter trunk sewers and outfalls down to the most intrica te re ticula tion systems, from precast concrete tunnel liners to Plastiline sh eet for insitu structures, e ven manhole s, you get them a ll from one source of supply.

Or Humes UPVC sewer syste ms - lightweight, re sistant to corrosion from efflue nt and H2 S, with a range of hi g h qua lity inj ection-moulded fitting s.

O r a combina tion of both, concre te and UPVC. But you ge t much more than that whe n you sp ecify Humes p roducts ..

Becau se you're dealing w ith one source, you ge t close lia ison at all levels, technical and non-technica l. With the one comp any , a nd w ith people you know, you are ensure d tha t design, manu facture and delivery p rograms are co-ordinate d to suit your construction sch e dules.

In sh ort, you get the tech nical service Humes is well known for.

And tha t's rathe r important these da y s.

Ask the man from Humes.

•

HUMES CONCRETE

PLASTICS

STEEL

185 Williams Street, Melbourne 3000 Telephone: 60 0221 VIC.: 17 Raglan Street, South Melbourne 3205. Phone (03) 60 022 1.

N. S.W.: Park Road, Regents Park 2143.

Phone (02) 644 2351.

QLD.: 189 Mon tag ue Road, South Brisbane 4101. Phone (07:) 44 5881.

S.A. : 78-82 West Beoch Road, Keswick 5035. Phone (08) 297 1011.

W.A.: Salvado Road, Wemb ley 6014.

Phone (092) 87 23 11 .

,V. L Reidr&dt Rocrd, Wi11t1E'ii't'ie 5789. Phone Darwin 84 3388 TAS.: 2 Kirksway Place, Hobart 7000.

Phone (002) 23 7 43 I.

HC524H

EDITORIAL COMMITTEE Chairman: C. D. Parker Committee: M. Dureau G.R. Goffin L.C. Smith F.R. Bishop R.L. Clisby Joan Powling B.S. Sanders A.G. Longstaff W. Nicholson E.A. Swinton A. Macoun Publisher: Hon. Editor: A.W .W.A. A.H. Truman

BRANCH CORRESPONDENTS CANBERRA A.C.T.: A. Macoun, P.O. Box 306, Woden, 2606.

wale~

Jo~~s~:

3

;~~

Official :f !AUSTRALIAN WATER AND I

IWAS'FEWAT£RAS"SOCTATToN] Vol. 3

No. 1

March 1976

CONTENTS Editorial - The Journal

5

Letters to the Editor

6

Association News

8

NEW SOUTH WALES: M. Dureau, Envirotech Australia Pty. Ltd., 1 Frederick Street, Artarmon.

Literary Review

10

The Cost of Physical Treatment (PCT) Waste Water (S. Y .Ip. *

11

VICTORIA: A.G. Longstaff, Gutteridge Haskins & Davey, 380 Lonsdale Street, Melbourne, 3000.

Construction and Calibration of Dissolved Oxygen Probes - Peter Gebbie*, C. D. J. Fell and A.G. Fanet

14

QUEENSLAND: L.C. Smith, 24 Byambee Street, Kenmore, 4069.

Microbiology of Water in the 1970's Locy R. Alford, B.Sc.*

15

Products, Projects and Personalities

19

Conference Calendar

22

SOUTH AUSTRALIA: R.L. Clisby, C/- E. & W.S. G.P.O. Box 1751, Adelaide, 5001.

WESTERN AUSTRALIA: B.S. Sanders, 39 Kalinda Drive, City Beach, 6015.

TASMANIA: W. Nicholson, 7 Swansea Court, Lindisfarne, 7015.

NORTHERN TERRITORY: C/- N.R. Allen, 634 Johns Place, Nightcliff, Darwin, 5792.

Editorial Correspondence: Hon. Editor, A.H. Truman, C/- Davy-Ashmore Pty. Ltd., P.O. Box 4709, Melbourne, 3001.

Or to State Correspondents.

Advertising Enquiries: Mrs. L. Geal, C/- Appita, 191 Royal Par., Parkville, 3052.

Phone: (03) 347-2377.

INSTRUCTIONS TO AUTHORS Articles should be of original thought or reports on original work of interest to the members of the A.W.W.A. and preferably not more than 5,000 to 7,000 words.

Full instructions are available from Branch correspondents or,the Editor .

FRONT COVER Aerial photograph showing construction progress, November 1975 of the Lower Molonglo Water Quality Control Centre at the junction of the Molonglo and Murrumbidgee rivers . This $30 million facility will cater for future sewage treatment needs of the Australian Capital Territory. Construction by The Ralph M. Parsons Company Pty. Limited and Dillingham Constructions Pty . Limited .

As Project Manager, Parsons is responsible for mechanical, electrical and instrumentation detail design , procurement, construction and commissioning .

Dillingham is carrying out the civil and architectural works. Construction is being supervised by the Commonwealth Department of Construction for and on beha lf of the Nat ional Capital Development Commission.

The LMWQCC has an average design capacity of 109 MI/ d and a peak wet weather flow capacity of 545 MIid . A combination of physical, chemical and biological processes is employed to achieve closely contro lled effluent characteristics .

Construction of L.M .W .Q.C.C . is being supervised by the Australian Government Dept. of Construction for and on behalf of the National Capital Developmental Commission .

(OD) INDUSTRIAL ENGINEERING LIMITED restore the ENVIRONMENT . . !

CLEAN AND CLEAR WATERWAYS with

fflud Cat UNDERWATER WASTE REMOVER

MUD CAT dredges have been specifically design ed for the economical removal of pollutant substances from waste settling ponds, weed-infested lakes and st reams and for channel clean-out . Th eir unique features permit the removal of deleterious matte r, weeds , silt, sand , sludge and industrial wastes with the minimum of wate r turbidity, thus allowing the pond, lake , stream or chann el Deve loped by the Nat io nal Ca r Re nt al System In c .. o f U.S. A. AUSTRALIA WIDE DISTRIBUTORS :

to ope rate o r flow normally during th e cl ean-up operation . Two machines are available, th e MC10 whi ch will ope rate to a depth of 10'6" and the larger MC15 wh ich operates to a depth of 15'0". Both machin es are pro pell ed in both th e forw ard and reve rse directions by winching along a w ire rope which is furnish ed in th e form of a harn essing kit.

/jffl\

INDUSTRIAL ENGINEERING LIMITED ~ :,~~~;,;:~~;TP:'oEi; ~~~;;,c~:~Ex

AA301ss

Sates and Service through the I.E.L.-CONTRACTING PLANT ORGANISATION CONTRACTING PLANT (QLD.l DIV. CONTRACTING PLANT IN .S.W.l DIV. CONTRACTING PLANT IVIC.l DIV. SOUTH AUSTRALIAN DIV. INDU STR IAL AVENUE WACO L 288 PARRAMATTA RD . AUBURN (TASMANIA) 585 GRAND JUNCTION RD .

PH ONE 72 2122

PHONE 6480301

cnr. FOOTSCRAY RD . & DUDLEY ST. , WEST MELBOURNE. PHONE 328 4571

WEST AUSTRALIAN DIV.

cnr. RUSSELL & SPARKS RDS .

GE PPS CROSS PHONE 62 661 2 STH.COOGEE . PHONE 90 142 MCI

2

J

Mono announce the only submersible sewerage pumps to be unaffected by disposable nappies. ordinary nappies. · wet-strength fibres. pantyhose. and solids up to 6''diameter.

Th e Monta pumps , fro m 2 to 75 HP, wi th 3" to 6" so li ds capacity , are complete ly se lf-clearing .

Other benefits inc lu de easy installation and maintenance.

The pump is guided into pos ition by a slid e tube and the res ilient face on its discharge branch sea ls the connection wit h the disc harge pedestal.

Call Mo no 's Water and Waste Treatm ent Division for fu ll detai ls of how th e Monta pu mps ca n handl e yo ur sewerage prob lem.

(?Ol)UGi][p@ (AUSTRALIA) PTY. LTD. Head Office and Works: "Mono House", 338-348 Lowe r Dandenong Rd ., Mordi all oc, Vi c. 3195. Ph one : 90 5211.

Interstate Offices: NEW SOUTH WALES: Kirrawee, te lephone 52 1-56 11 0 QUEENSLAND : Kedron, te l ephone 59-6466 SOUTH AUSTRA LIA : Fl inders Park, t elep hone 43-975 4 0 WESTER N AUSTRA LIA : Be l mont, te lephone 65-5244 0 TAS MANI A: Moonah, te lep hon e 28-0353 0 NORTHERN TERRITORY: Winne l lie, telephone 84-3099. Alice Springs, te l ephone 2-29 13 LI AGENT S IN : Papu a an d New Guinea, 344·P·042 Indonesia. Fiji, The Philippines.

=

3

Pumps are our business Whether you want to supply water to - or de-water from a mine, install a fire fighting system , or handle low volume, high pressure slurri es, McPherson 's have the pump for you. Pumps such as • th e all-Australian all-metric Ajax Internationa l Series back pull out pump s; • the Pe erless vertical line shaft and submersib le turbin e pumps ; • Ritz submersible twin flow pumps developed for the mining indu stry in sizes to 2,000 hp; and• th e Seeberg po sitive di sp lacement pumps are j ust a few of th e pumps manufactured and / or distributed by McPherson's Limit ed Pump Division.

Mc Ph erso n's, with a nationa l coverage by its branc hes and distributors, provides convenient sales and se rvice fac ilities to assist you before and after you purchase your pump.

McPherson's Ltd. Pump Division Melbourn e 699 3588 Sydney 516 1633 Brisbane 52 2233 Adelaid e 46 0271 Perth 61 8888

6310MPIPDN

4

FEDERAL SECRETARY: R.F. Goldfinch, P.O. Box 359, Canberra, 2601 BRANCH SECRETARIES: Canberra, A.C.T. D. Butters, Cl- Dept. of Housing & Construction Phillip, A.C.T., 2606 New South Wales: Dr. D.T. Lacey, 16 Fairy Dell Close, Westleigh, 2120.

Victoria: R. Povey, Cl- S.R. & W.S. Commission, .590 Orrong Rd., Armadale, 3143.

Queensland: A. Pettigrew, P.O. Box 129, Brisbane Markets, 4106.

South Australia: A. Glatz, Cl- Engineering & Water Supply Dept.

Victoria Square, Adelaide, 5000.

.EDITORIAL THE JOURNAL

Those of us who have been closely associated wit h the development of the Association Journal are genuinely sorry to have to report the death of our Publisher John Craig. It was the init iative of John Craig in 1973 by his approach to the Association, whi ch led to the decision to publish a Journal. His experience and advi ce has been invaluable in these early days .

It is appropriate here to explain the financial basis on wh ich the a Journal has been established and is operating.

(1) All costs of production of the Journal are met by th e Publ isher and covered by his right to sell 40% of the space as advert ising.

(2) The costs for mailing, distribution and postage, amounti ng to some $3000 per year, are to the Association and need to be met annually from Federal Council funds Association. Membership Subscriptions were raised in 1974 to meet this expenditu re.

(3) Any sales of the Journal (at $1 per copy) to non-members, are an offset against Editorial expenses.

(4) Copies are prov ided free to all Members and are covered by subscriptions .

Arrangements are now being made on a similar basi s with another agency and it is expected that these will be as satisfactory to the Association, as has been our association with John Craig .

C. D. Parker, Editorial Corrmittee.

Western Australia: B.S. Sanders, P.O. Box 356, West Perth, 6005.

• JOHN CRAIG -

Tasmania: P.E. Spratt, Cl- Fowler, England & Newton, 132 Davey St., Hobart, 7000.

Northern Territory: N.R. Allen, 634 Johns Place, Nightcliff, Darwin, 5792.

MEMBERSHIP CERTIFICATE "Those requiring a certifi cat e o f m embership in th e Asso ciati on ar e ad vi sed that th ese are now avai lab le and w ill be prov id ed upon rece ipt by the Fed eral Sec ret ar y of a w ritten req uest fr o m the member."

AN APPRECIATION

John Craig was not known to many members of the Association, but as Publisher of "Water" he was closely associated with the Journal and the Journal committee since our first publication in March, 1974. His sudden death in January is a loss to "Water" and has been particularly felt by the Journal Committee who desire to express th eir appreciation of the enthusiasm and effort he contributed.

John spent many years in pioneering advertising in rad io in N.S.W. His enterprising nature and his charm must have brought him good resu lts in that media. He retired from radio and transferred his activities to publishing here in Victoria. He contributed considerably to the initial phases of our Journal and had much to do with its promotion - he handled advertising and publication from the inception . John was always pleasant and helpful to work with, and the Committee will miss his ready co-operation and assistance.

From the Association and the Committee, our most sincere condolences to Mrs. Craig.

C. D. PARKER, CHAIRMAN - JOURNAL COMMITTEE.

5

Letters to the Editor An apology f irst to Professor W. D. Wi lliams for not naming him as the author of the first letter in Vo. 2 No. 4.

"BIOLOGICAL, CHEMICAL AND RELATED ENGINEERING PROBLEMS IN LARGE STORAGE LAKES OF TASMANIA" Dear Sir, I refer to the letter in the December 1975 (Vol. 2, No. 4) issue of "Water" under the titl e "Ecological Management of Tasmanian Water Storages" by W . D. Williams wh ich commented on a paper written by me over five years ago, in November, 1970.

The paper , "B iological, Chemical and Related Engineering Problems in Large Storage Lakes of Tasmania", was subsequently published about two years later, together with other selected papers from the international symposium held at Knoxville, Tennessee by the Committee on Wat er Research. It was re-published in " Water" in December, 1974 (Vol. 1, No. 4) . Some two years ago I supp lied colleagues and other interested parties both locally and interstate with re-p rints which were also given to those who subsequently requested copies, including a number from Paris, Moscow and other overseas countries . A ltogether a fairly substantial number was distributed.

Both publications refer to the abridged form of the paper(s) whilst the re-prints included the note, inter alia ... "Published papers have been reduced by approximately 1 /3 by the Editorial Committee for final printing in one vo lume . In my case this was mainly achieved by eliminating some sections, reference s, etc.".

It is ev ident that the paper has rece ived a wide circulation and I am therefore surprised to see at this late stage the first criticism of it, particu larly as a number of favourabl e comments have previously been received.

The view that a "nu mber of detailed crit icisms can be raised" is accepted . I could make a few myself as any author can looking back f ive years , however, my qualification of terms in "senescent neo-o l igotroph ic and supermesotroph ic" (from senescent = ageing; modified , super above) are . neo sufficiently descriptive to be understood and are justified when one considers the current arguments as to what the terms mean and the practical difficu lties in accurately classifying the storage lakes.

Lake St. Clair has a surface area of 28 Km (11 sq. mi les) and a max imum depth of 200 m . Neither of these d im ensio ns were changed very much by raising the level by about 3 m in 1937, although th e f low regim e was changed.

The factors in favour of making this lake a "bench -mark or reference lake" are

=

6

=

• • too numerous to describe here, but include access ; past and future long term freedom from pollutants and variations in its (present) regime ; 40 years of hydrological record which will continue into the foreseeable future; known geomorphology ; its size , altitude , relevance to the other storage lakes; its situation in a State park, etc. , etc . It also has the practical advantage that it is visited regularly by appropriate technical field staff .

Mt . Solitary , the largest inland island in Tasmania, offers facilities which are unique. If dedicated it could be totally protected from human influence, particularly fire . There is no reasonable way other tracts of land in the S. W. of Tasmania or elsewhere can be similarly protected . It is strange that my critic and his colleagues should find this proposal "ill-founded". Dr. J . Berry, the internationally famous Scottish ecologist who made two visits to the site in my company in 1970 and 1975 was in favour of it.

Similarly the statement that the Hydro-Electric Commission has not engaged in significant limnological investigations shows a lack of knowledge, confuses the value of published papers with practical work going back to c. 1950 (and earlier for certain aspects) and overlooks the different roles of engineering-oriented application and research . Tasmania's strong interest and involvement in limnology owes much to H .E.C. in itiatives and support as any fair appraisal would acknowledge.

My statement as quoted from page 62 is completely factual and is not affected by reference to University and other studies which were intermittent and brief. Page 65 of the book " Lake Pedder" , pub I ished by the Lake Pedder Action Committee and others in July 1972, refers to environmental assessment " The H .E.C. commissioned its own study (the only study carried out)" .

That there were no lengthy independent researc h projects or sabbatical years spent studying Lake Pedder and adjacent regions detracted somewhat from its claims to great scientific interest.

As a critic of the H . E.C. and a member of the Com monwealth Government 's Lake Pedder Committee of Enquiry whose recommendations were rejected by both the Government and the H. E.C ., W. D. Williams is unlikely to agree with me on all the contents of the paper, nonetheless, I assure him that although debatable the proposals to which he ob jects were not ill-founded and that my statements were meant to be taken seriously .

During nearly 30 years involvement with (as quoted from W. D. Williams ' letter) " the body large ly responsible for the management of Tasmanian Lakes and Impoundments as water storages" my advice has frequently been acted upon .

Henry H. McFie, F.I.E. Aust.

RESEARCH IN POTABLE WATER SUPPLY FIELDS Dear Sir, With reference to the abovementioned research I would like to enquire whether there have been any publications in Australia concerning research on the following subjects: 1. Water losses in pipe distribution systems (i.e . unaccounted for water) .

2. Water demands in urban areas (i.e. domestic , industrial and commercial) .

3. Characteristics of, and Methodology for measuring water filtration plant wastes .

I would appreciate it if any such publications could tfe made available to us . thanking you kindly, Yours faithfuly, (Signed) Prof. F. A . van Duuren .

Ed. Readers please correspond direct with Professor van Duuren if you can assist him .

Address : Department of Chemical Engineering, University of Pretoria, PRETORIA 0002 , SOUTH AFRICA .

WATER HAMMER

Dear Sir, The innovative approach of Dr. Guy (" Suppression of Domestic Water Hammer Noise by a Simple Wave Dispersion Technique" - Water Vol. 2 No . 4, Dec . 1975) to the design of a noise attenuator for use in water supply plumbing in properties is commendable for its simplicity and potentially cheap cost . Noise attenuators currently available generally use a compressible balloon or bellows , are more complex in design and are therefore fairly expensive.

In recent years there has been a noticeable irfcrease in complaints from householders of disturbing noises within the water service, either in the form of "water-hammer" or " metertick ". In many cases the noises are even sleep-disturbing particularly when the noise emanates from another property or tenement . The proliferation of highdensity flat and villa- unit development has considerably magnified the problem .

Where the source of water-hammer can be identified the most effective remedial action is, of course, to el im in ate or reduce it to an acceptable level at the outset . Th is can often be ac hi eved by proper servicing and adjustment of the offending equipment if it be a quick acting solenoid type valve, a check-valve or similar. In many cases the noise is attributab le to poorly clipped pipework, particu larly copper services which are lightweight and tend to "whip" w ith the internal pressure wave.

There are many cases however, where every effort to subdue the noise still fails to control the situat ion and it is then that those responsib le for plu mb in g maintenance turn to devices such as that proposed in an endeavour

to cope with the problem, and it is here essential to realise the importance of position ing a "noise-arrestor" in an effective location, usually close to the noise source.

Experience has shown that the effectiveness of attenuators depends on both the soundness of design of the unit and its positioning within the troublesome service, and here it would appear that the arrestors shown in Figure 2b of the paper would be best located downstream of the meters, thereby protecting each protecting from its own "meter-tick" as we ll as the "tick" from adjacent properties. It shou ld also be noted that many Water Authorities require separate tappings or connection to the reticu lation for each property, thereby reducing the possibili ty of transfer of water noise between properties.

The pub li shed test results for the attenuator are prom ising but as experience shows that noise is more preva lent on high-pressure supplies some - indication of effect iveness on services having pressures above 100 ps i cou ld be more mean ingful and practica lly acceptab le. Another concerning factor would be the possibility of the generat ion of undesirable bacterial slime-growth on the foamed rubber or polyurethane in service. If suc h growth deve loped it cou ld reduce the effectiveness of the unit, contaminate the water and possibily cause blockage troub les by event uall y breaking away in large sections and causing problems at orifices, etc. It would, of cou rse, be also essentia l to show that the attenuating material itself did not deteriorate in service and break off to in trod uce foreign matter wh ich once again could cause restrictions or blockages in the supp ly. Th is prob lem is not introduced by the present ly availab le attenuators.

Fina lly it cou ld be stated that in practice, water noise is d ifficult to identify and quant ify, as is the acceptance by peop le to leve ls of noise.

Much depends on the psycho logical feel ings of people in their various moods and temperaments throughout the day, and from day to day . Many no ises which at one time are tolerated, beco me at ot her ti mes intolerab le.

Quite often it is found that the mere action of adding a "noise-reducer", however effect ive, is the catalyst to psycho log ical acceptance of the "improvement and acceptab il ity" of the no ise leve l.

If, however, it can be practically demonstrated that the wave-dispers ion t ype atte nu ator deve loped by Dr. Guy can effective ly reduce impulsive hydrau lic noises in property water services, if it ca n also meet t he Water Authorities requirements with respect to contamination and introduction of fo reign matter, and if the price is, as expected, competitive with currently avai lable units, then it wi ll be a most wort hwh il e cont ribution to water supply eng ineering .

R. A. Morgan, D. W . Brewer, Melbourne M.B .W.

AUTHORS'RESPONSE Dear Sir, In reply to the comments made by Messrs Morgan and Brewer concerning my art ic le on the application of a wave dispersion attenuator for noise problems in a domestic water supply, I would like to thank them for the interesting points he raised and the constructive nature of their questions.

I have made some noise level measurements recently in rooms worst affected by water meter " tick " from the same dwelling and that from next door.

Surprisingly, the worst affected room is often a bedroom so the comment Mr. Morgan made about sleep disturbing noise is quite important. For example , the recommended noise level for a bedroom environment is up to 30 db"A", however, I have measured noise levels of between 50 dBA and 60 dBA caused by watermeters . Also approximate measurements of the impulsive noise from valve turn off exceeded the meter noise by more than 10 dB .

I agree with his observation that the attenuator would be best located just downstream of the watermeter. We have recently installed noise attentuators in this position in two domestic water supply systems. Its effectiveness in reducing watermeter noise from the house supply and that from next door (and also the next door valve turn-off noise) was quite remarkable . In one case th is noise was reduced from 52 dBA to 34 dBA and in another case (installed by the ACT Department of Housing) the noise level was reduced from 54 dBA to 40 dBA . In both cases, however, the noise from the next door meter or valve turn-off was completely removed and that measured from the subject house water supply was found to be above the background noise level on ly because of noise to the house emmanating at the taps and therefore, not pass ing through the attenuator.

This raises the question of how to eliminate water noises from valves w it hin the house.. It would be extravagant in the extreme to position a small attenuator ¡ upstream of every water va lve in the house, however, there are often water using devices within a house which create considerable water hammer when in operation. Washing machines and dish washers have been found to create th is problem since they use solenoid operated water valves. It is entirely feasible, therefore, to fit a sma ll attenuator just upstream to the water supply in let to this type of machine. In just such a practical test, an attenuator was inserted into the cold water supply to a washing machine situated in a laundry external to the house . Normal ly when the washing machine was in operation, severe water hammer waves travelling from the machine and into the house system bad ly affected the master bedroom area. After fitting an attenuator having overa ll dimensions of about 1.75 ins diameter by 8 ins long in the inlet hose

to the machine , the noise annoyance within the house was completely removed .

With regard to possible environmental problems associated with this type of attenuator, a domest ic main line attenuator is already successfully operating at a mean static pressure of about 100 psi.

Furt herm o re , a specimen of the foam rubber hose used in the attenu .. tor was subjected to a static pressure of oil of 1600 psi without change in structural properties .

It is unlikely , therefore , that the material will break down due to overstress or chemical break down since foam rubber in water is extremely stable chemically .

The possi bi Iity of bacterial growth causing a problem in this type of attenuator is not so easy to assess in relation to ex isting systems . Points in favour of the resistance to damaging bacterial growth are : (a) there are no still water regions in the device ; and (b) the foam rubber tube used has a continuous smooth rubber skin over all exposed surfaces .

It is a known fact , however, that on a microscopic level , bacteria will grow more readily in a rubber surface than say copper, which has the added advantage of high to x icity to bacteria. It could be argued though, that since water flows over all the smooth inner surface of the foam rubber then it is likely that any slime formed would be washed away before a large build up occurred. Furthermore , the existence of a film of slime on the foam rubber lining will definately have no ef fect on the performance of the attenuator because the acoustic properties of the slime will be very similar to those for water.

In conclusion , the~fore , there is now substantial measured proof of the high level of effectiveness in reducing this type of noise by a wave dispersion type attenuator. The mechanical durability of the lining material is unlikely to cause operational difficulties over the long term but resistance to bacterial growth prob lems in the foam rubber lining compared to a copper tube surface cannot be assessed at this stage. It is obvious that such an assessment can only be made over a period of time in service . This is the approach of the Water Supply Department in the ACT Department of Housing , who have recently installed an attenuator in a domestic water supply where pressure excursions of up to 140 P.S.I. were not uncommon . Finally , an appro ximate cost estimate of a quantity produced attentuator is considerably less than any current marketed alternative method having comparable effectiveness.

Dr. T. B. Guy , Department of Mechanical Engineering, AMC , Duntroon , ACT 2600 .

7

eJ

ASSOCIATION NEWS

" Aspects of Water Pollution in South Australia " and the problems of inhabited catchments and the River Murray as a raw water source .

The next meeting of the Association wil l be a Dinner/Ladies' Night on 7th May , 1976 at the Ambassador Hotel.

An inspection of the Lower Molonglo Water Quality Control Centre is planned for Saturday, 22nd May , 1976.

TASMANIA SOUTH AUSTRALIA The first General Meeting for 1976 of the S.A. Branch of the AWWA Inc . was held on Friday , 27 February , 1976. A very interesting programme was enjoyed by sixty-eight persons .

Dr. David Mitchell, of the University of Rhodesia, spoke on " Water Weeds ", outlining the different life forms of submerged, attached floating , emergent and free floating vegetation.

Examp les of major problem weeds on Lake Kariba in Central Africa (waterfern , Salvinia) and in Queensland (water hyacinth, Eichornia) were illustrated and discussed with respect to their possible distribution in the River Murray system . The growth pattern , potential uses and control measures were also discussed with a view to management of the River system and associated irrigation areas.

Mr. L. F. Reynolds, Dept. of the Department of Agriculture and Fisheries, spoke on "Fishes of the River Murray " , both native and exotic species including the Common (European) Carp (Cyprinus carpio). Decline in native fish populations appeared re lated not to competit ion from introduced species, but to environmental factors modified by man.

The next meeting of the Branch will be held on 28 May , 1976. The speakers w ill be : Mr. S. Lewis, Department of Env iron ment and Conservation , and Dr. D. Steffensen , Engineerin g and Water Supply Department, speaking on " Marine Stud ies in Gu lf St .

Vincent " .

CANBERRA The 26th Genera l Meeting was held on 18th December, 1975 , and was addressed by Professor Daniel Okun of the University of North Carol in a who spoke on " The State-of-the-Art". Prof .

Okun gave his impressions and experiences of the success of the English River Authorities, Federa l Law PL92-500 , and water use and re-use and the significance of synthetic organic chemicals .

The 27th Genera l Meeting was held on 5th February , 1976, to coincide with the AWRC Symposium on "Eutroph ication" held at the Australian National University . The meeting was addressed

by Mr. Doug Lane, Chief Chemist of E & WS and Vice-President of the South Australian Branch. Mr. Lane spoke on 8

The first General Meeting of th e Branch for this year will be held at the H . E.C. Theaterette on Wednesday , 31st March . The speaker will be Mr. W .

Piesse , Investigation Chemist, Launce ston City Counc il , who will speak on the sampling of urban industrial wastes . Mr. Piesse has been investigating trade wastes and their associated environmenta l effects for the past three years and his ta lk shou ld prove interesting to all members.

Further meetings for the year have not yet been finalised , but it is planned to have a Genera l Meeting in May , when it is hoped a speaker from the ANZAAS Conference will be invited to deliver a paper on some appropriate subject . A July seminar is also being planned, the subject being the " Advanced Treatment of Industrial and Domestic Wastes", with three speakers taking part .

The membership of the Branch has continued to grow , due mainly to the strenuous efforts of the Membership Sub-committee . Three additional sustaining members have been added to the six listed in the September, 1975 issue of Water. These new members are: Clarence Municipal Council Goliath Portland Cement Co .

Launceston City Council.

We are indeed happy to have the added support of these new members .

Their acceptance of membership augurs well for the future of the Associat ion in this State.

QUEENSLAND Queensland Branch activities com menced on 3rd March , 1976, with a Genera l Meeting at the Polonia Clu b, Brisbane . Guest speaker for the night was Captain C. Tucker of the Harbours and Marine Department with an address ent itl ed , " The Good Old Days are Gone Forever".

Captain Tucker spoke of faci lities and activities of his Department in combating pollution of tida l streams and harbours in the State.

In particu lar he outlined the facilities at hand for combating pollution by oil.

Further Branch activities for the year include: April 14: Joint meeting with the Corrosion Association. Mr. G. Kelly , " Corrosion Effects of Various Heaters ". .June: B . Rigden & P. Hetherington, " Treatment of Tannery Wastes " .

,July: A.G.M. August 4: Joint meeting with Institution of Engineers . A . Pettigrew , "Industrial Waste Water Treatment" . !iept.: Field Day .

8th I.A.W . P.R. Conference A Queens land Branch sub-committee t,as produced a brochure entitled, " Invitation to Visit Queensland" to be t, anded to conference delegates . The /b rochure out I ines post-conference visits of both technical and tourist nature which will be available in the State.

NEW SOUTH WALES Shell Visit With the kind permission of Mr. Paul Huggins, the Refinery Manager, two visits were arranged for members and their guests to in spect the sophisticated Water Reclamation Plant at Shell 's Clyde Refinery. These visits took place on the 11th February , 1976 and the 3rd March , 1976 and were preceeded by drinks and a buffet meal. In alt 80 people were shown over the tertiary treatment plant which includes Dissolved Air Flotation, Oxygen Control Activated Sludge , upftow tmmedium Filters and massive force-draught Cooling Towers.

Regional Conference Well , its on again, the N .S.W. Branch Regional Conference which will be held this year at the El Lago Commodore Motel , The Entrance . The theme for the conference is " Water, Water Everywhere . . . " From the app li cations received at the time of going to press, it seems that this conference will be very successful. An interesting feature of this year's conference is that a Golf Day will be hefd at the Tuggerah Lakes Golf Club on the preceding Friday .

The papers al I fol low the genera l theme of water supply and treatment as can be seen from the listing below: " Regional Water Supply Scheme for Gosford -Wyong Area", by P. R. MacKenz ie, Project Engineer, Department of Public Works , N.S.W. K . R. Galbraith , W.S. & S. Engineer, Gosford Shire Co uncil. " Water Supp li es for Thermal Power Stations " , by C. G. Coulter, Engineer, Project Planning, Power Development Division, Electricity Commiss ion of N.S .W. " The Direct Filtration Process and Its Application to Sydney Water Supply", by Dr. G . R. Grantham , Director, Camp Scott Furphy Pty . Ltd. K . A . Waterhouse, Designing Engineer , M.W .S. & D.B . " The Design, Construction and Commissioning of the Muswellbrook Water Soften ing and Purification .

Plant", by J. E. Mccann, Director, Gutteridge Haskins & Davey Pty. Ltd . " Potential Amplification of Newcastle Water Supply" , by P. Michael, Hunter District Water Board.

'

"New Developments in Flexib le Liners for Water Containment", by Dr. K. Martin, Dupont (Australasia) Ltd. A full report on this conference will be in cluded in the next edition of "Water".

Future Functions

5th May, 1976 A Genera l Meeting in which there wil l be a pane l discussion on Water and Wastewater Treatment Equipment.

22nd May, 1976 A wine tasting wi ll be held at Herm itage Wines in George Street, Sydney, near The Rocks.

9th June, 1976 A General Meeting at which Professor Ratcliffe from the University of N .S .W. will speak on "Training Potentials in the Field of Public Health Engineering and Pollution Control" .

21st July , 1976 Annual General Meeting .

VICTORIA

8th I.A.W.P.R. Conference - Sydr,ey 1976

The Victorian Branch of the A.W.W.A. extends an invitation for delegates attending the I.A.W.P . R. Conference to visit Victoria .

A Hospitality Committee has been formed for the purpose of arranging inspections of works and facilities of technical interest. Such items will includ e the M.M.B .W. sewage disposal facilities and pi lot plant stud ies at Werribee, the recently comp leted South Eastern Purification Plant , the C.S .I.R .O. Research Station at Lower Plenty and works to sewer towns on the eastern shores of Port Phillip Bay. Further suggestions for items of interest or enquiries could be directed to any of the following members of the Hospitality Committee: Brian Lloyd (or Jim Greer) Melbourne and Metropo litan Board of Works . Tele . 615-5281 .

A lan Longstaff - Gutteridge Haskins and Davey , Tele. 67-9341 .

Bill Evans Water Commission.

Te le. 5080-272 .

AWWA

The first meet ing of the year on the 10th February was addressed by Mr. A. Stratto n - Director of Hawker Sidde ley Water Engineering Ltd. U.K. Attendance at this meeting was we ll over 70 one of the highest number on record.

Mr. Stratton gave a relatively brief orat ion on the Kind and Futu re Trends of the Activated Sludge Processes.

Fo llowin g hi s address he then opened the meeting for lively discussions and questions on the top ic. The high attendance and large number of questions was sufficient proof of the apprec iat ion by the aud ience of his address.

An inspection of the MMBW's sewerage farm and Pi lot Study Plant at Werribee created a great deal of interest amo ngst the Branch's members. Th is inspection was attended by the record number of some 110 persons on the aftern oon of Friday , 27th February . The inspection centred on the Areas of Traditional Farm Treatment, and the $1.3 M Pi lot Study Plant for the proposed activated slud ge plant to augment the Board's existing sewerage farm . Thi s event was most successful due largely to the efforts of the Board's staff, particularly Messrs. W . Robertson , J . McPherso n, W . Kirby and K. Levey.

The last genera l meeting was addressed by Mr. R. J . Macklin of Kinn aird , Hill and de-Rohan and Young , Cons ultin g Eng in ee rs. Mr. Macklin gave a most interesting talk on the design aspects of the provision of waste treatment faci l ities for the text il e industries at the inland country town of Wangaratta, Victoria . His address was appreciated by al l present.

The Branch intend s to hold another Weekend Conference this year. No details are ava il able at this stage except that the likely venue for this event w ill be Ph ill ip Island . Further information wi ll be made ava il able to Branch Members in the near future.

George Gollin retires

At the end of December last , George Goffin retired from the position of General Manager Technical of Humes Ltd . after some 22 years with that company.

George jo in ed Humes in 1953 to pioneer their prestressed concrete work, and was short ly after, appointed Chief Engineer. In subsequent years he served successfu ll y as Manager of the Co ncrete Production and Engineerin g, Technical Concrete and R & D Divisions before becoming General Manager Tec hni ca l.

He has travelled extensively overseas, estab li shed lo ng- last in g technical associations in many countries, and fostered the R & D orientat io n which has played an important part in his company 's development.

He has worked and (we are pleased to note is continuing to work), tirelessly for this Association . As Preside nt, he contribu ted greatly to the success of the 1972 Biennial Conference in Adelaide and is currently a Federa l Counc ill or, Victorian Committeeman, and, of course , Ed itorial Comm itteeman for this Journal.

His profess ional experience has covered all major engineering fields Consulting Engineering, Local Government (as Chief Engineer and Manager of the Department of Works - Brisbane City Council) and more recently, Indu stry . This experience has been of great value to Humes and to this Association.

Whilst his experience will be sorely missed by th e concrete industry , their loss will be the Association 's gain .

We hope to see George Goffin active in the Association for many years to come.

DO YOU WANT LANDSAT? The Association has been requested to ass ist in the conduct of 'a survey of possible applications for the establishment in Australia of an operational satellite system in Australia known as LANDSAT. An obvious example of a LANDSAT application is in the area of water resources management. Such a system would monitor the major hydrological resources and condit ion s in a catchment using remote sensing techniques .

The system provides in a very short time information concerning the avail ability, movement and distribution of water in a river system .

The satellite becomes an essential part of an earth observat ion system and when incorporated with information obtained by aircraft and ground measurements the data acqu ired by the satel l ite can provide a continuous description of the hydrology of a study area.

Other uses for LANDSAT could include A ir Po llu tion Observation, Monitoring of Agricultural , Resources, etc.

Persons interested in the LANDSAT programme are invited to complete a quest ionnaire which is one of a number of steps in estab li stfing the initial basis of demand for LANDSAT information in Austral ia.

In responding it is suggested that the following assumptions be used : (a) The cost of data wil l be genera lly sim il ar to that charged by EROS Data Center. That is, equating to a present figure in t he order of $3 for 56 mm black and white prints and ranging up to about $50 for large co lour composites . Tape sets currently cost $200. (b) The frequency of Australian coverage will be every 18 days (s in gle sate lli te) but this will reduce to 9 days if, as at present, two satell ites are in orbit.

Additional information which in terested persons may wish to add as having a bearing on the object ive of t he questionnaire shou ld be returned w ith the questionnaire.

Questionnaires are obtainable from Mr. B. Spark at The Department of Science, Scarborough House, WOD EN, A .C. T. Te lephone: (062) 83-2536 9

¡1

Lite rary Review ... " GROUNDWATER RESOURCES IN AUSTRALIA " Publish ed by the Aus tralian Water Resources Counci l and available from the Australian Government Printing Service, Mail Order Sa les, P. 0 . Box 84, Canberra, A. C. T., 2600. Price is $9.95 p lus $1 pos tage.

Two volumes co nsisting of four full colour maps , 174 pages of text, figures and tables. " Gro un dwater Resources of Au stra7 li a" recentl y publ ished by t he Au strali an Water Resou rces Cou nc il , is the second pub I ication to be produced by th e Au st ra li an Government and updates co ns iderably their 1965 publ ication " Revi ew of A ustral ia's Water Resources (Stream Flow and Underground Resou rces) " 1963 .

Th e publication set s out to fill the gap between th e plethora of short re port s, both pub li shed and un published , on gro undwat er at vari o us local ities in Au st rali a an d t he broad-brush approach of the former " Review ". In doing so , it shows the considerable advance both in data and understanding that has been achieved in the last ten years, but the data is sti ll spread rather thin and neither the maps nor the publication must be considered definitive , but rather as a " state of information " report .

The te xt ini.tially covers the historical and technological aspects of groundwater in Australia, as well as the necessary inputs for management of this resource. In this way, the editors seek to achieve a realistic understanding of the magnitude and limitations of the resource and the role it can play in Australia's development .

Four full colour maps of Australia are presented . The first sheet shows our " Principal Groundwater Resources ", wi th shadings to indicate salinity ranges , or lack of data . The data shown is selected to represent the principal aqui f ers on ly , where more than one ex ists . Accompanying notes on the map comment on yields, use potential and some special limitations , e.g. sod ium hazard .

The remaining maps disp lay the occurrence and salinity of groundwater in " Shal low Unconsolidated Sediments", in " Sed imentary Basins" and finally in "F ractured Rocks " .

Each map is backed up by text notes prepared by the various State authorities who sub-divide and describe the elements depicted on the maps relative to their State .

The detail included varies dependent on the amount of the work and development which has taken place, and seems to be up-to-date to about 1972. The data

presented seems to be somewhat se lective, and restricted to details of areas investigated mostly by Government agencies . Text notes covering some of the private groundwater supply developments, which occurred in Austral ia in the late 1960's and early 1970's, are either exc lu ded or only briefly mentioned, tho ugh the results are included on the maps .

In summary, " Groundwater Resources of Australia" should be valuab le as an initia l reference for engineers and industry in acquainting themselves with the state of knowledge of our groundwater resources for maybe the next three years. After that , the rate of expansion of data will have been such that , though the maps and text will still be re levant , they would in many cases be mod ifi ed and expanded by their authors.

Publ ications of this sort must never be seen as a basis for decision, but are useful as. a background in understanding our resources and the physical and managerial constraints which affect their ut ilisation. In . this context, the pub li cat ion is a valuable addition to our resource assessment publications.

S. Hancock

The first thing you need for water analY.sis-

d r-el f2

direct reading engineer's laboratory

•

With the DR-EL/2 you get all the equipment and reagents necessary for 27 different water and waste water tests - all in one carry case.

The DR-EL/2 incorporates a built-in spectrophotometer with a wavelength range of 400700 nm . Special wavelength dial positions are ¡ also marked for suspended solids testing (infra-red light ) and for measurement of colour in water.

Features: - Pre-measured reagents - Built-in conductivity meter (optional) - Battery or line power operation - Direct reading meter scales - Solid-state electronics.

SELBYS SCIENTIFIC LTD Melbourne 544 48 44 10

Sydney 888 7155

Brisbane 71 1566

Perth 21 9431

Ade laide 51 4651

Hobart 28 4691

.

j I

THE COST OF PHYSICAL CHEMICAL TREATMENT (PCT) WASTE WATER

by S. Y. Ip.* Summary The use of purely chemical treatment processes for waste water treatment has several advantages such as relative insensitivity to toxic materials etc., but few installations are yet in use. It has the potential to produce water of potable quality , but at h igher cost than bio logical secondary treatments such as trickling filters and activated sludge.

This paper presents a series of estimated Australian Costs for PCT treatment (excluding primary or secondary treatment costs), stage by stage for plants with operating capacities of 0.1, 1.0 and 10 mgd, in order to allow comparison against the economics of alternative processes, and also to enable comparison of costs between recyc ling treated industrial effluent and the purchase and disposal of water via sewers.

The plant is assumed to be situated in a capital city.

Introduction The CSIRO Division of Chemical Techno logy has built and operated a sma l I scale PCT plant at Lower Plenty, Victoria using pri mary eff luent 1 and water qual ity has essentially dupl icated that obtained overseas in sim il ar p lants at W indhoek2 and South Tahoe which use secondary eff luent3.

Cost estimates available in the open literature 1,2,4,5 , with the exception of Culp and Culp 6 do not provide a detailed breakdown so the data base used by Culp and Culp, collected prior to 1971, has been used together with typ ical Australian Chemical and energy costs.

The res ults have been ca lcu lated separately for three different operating capacities for each of the six unit operations (lime treatment, ammonia stripping, recarbonation and clarification, filtration, chlorination and carbon treatment) likely to be included in a PCT plant. It should be noted that the lime coagulation costs in th is paper are based on secondary treatment effluent on ly. The costs of lime coagu lation on primary settled or raw sewage have not been considered at this stage because of insufficient published operating data available from extended operation of large scale plants.

Basis for Estimation: 1. Cost data is based on informat ion avai lab le from a 7.5 mgd p lant at South Tahoe, U.S.A. during the period from February 1969 to December 1970 as published by Culp and Culp3,2. Suitab le factors are applied to allow for effect of scale and inflation as follows : Scale Factor: An exponential factor of 0. 73 is adopted for capital cost and 0.78 for operating cost, as recommended by Rosander 7 and Marshal l.a . Figures of 0.2-0 .3 are we ll documented but experience with the Lower Plenty Plant is in l ine with the higher f igure.

V. C. Marshall8 Rosander 7 Plant Capital Cost Factor 0.66-0 .78 0.73 Operating or Labour Cost Factor 0.70-0 .90 0.78 Inflation Factor: An inf lation factor of 1.53 is app l ied to the capital cost data of Culp and Culp . This factor is derived from the CE Plant Cost Index published regu larly in "Chemical Engineering" (McGraw-Hill), which includes four major components: Equipment , instal lation , labour, building and "B . Econ . (Monash) ASTC (App. Chem .) ASTC (Chem . Eng.) ARACI , CSIRO, Division of Chemical Technology , South Melbourne, Victoria.

supervIsIon man power as we ll as a productivi ty fact or of 2½ % on labour and engineering components. The re levant indices for 1969 and June 1975 are 119 and 181 .7 respect ively , thus the cost of a plant in 1975 is abo ut 181.7/1 19 or 1.53 times that of 1969.

2. In deriv ing the average fixed cos t , t he following assumptions are made: Depreciation rate-4% Interest rate on capital-10% Maintenance rate as derived from Culp and Culp Lime treatment 1.2% p.a.

Lime mud dewatering 8.0 % p.a.

Lime mud reca lc in at ion 2. 0% p .a.

Ammonia stripping 1 .0% p. a.

Recarbonation and c larification 3.0% p. a.

Filtration 1.0% p.a.

Chlorination 0.5% p.a.

Carbon column 1.0% p.a.

Carbon regeneration 4.0% p.a .

Conversions-One A ustra l ian doll ar equals 1.25 US dollars and one Imperia l gall on eq uals 0.8 US gallon , i.e., conveniently, $A per imp. gal. = $US per US gal.

3. In deriving the average operat ing cost , t he follow ing unit costs are assumed based on current Au stralian market prices: Labour cost (direct + ind irect) $8.0 / man-hour Fuel costs (nat ura l gas) 8 cent s/ therm 2 cent s /KwH Power cost 0.89 cent/lb Lime Cost Chlorinated Ferrous Sulphate 1.82 cents /lb 10.0 cen ts/lb Chlorine 11 .0 cents / lb Carbon Diox ide 22.0 cent s/ lb Activated Carbo n 2.68 cents / lb Make Up Carbon (rege nerat io n co st) 0.02 cents/lb * Solid Disposa l Cost "In general , this depends on the distance of hauling and on the dumping charge at disposal site.

•

DETAILED ESTIMATES Phosphorus Removal 1. Without Recalcination 1.1 Lime Treatment

0. 1 1.0 10.0 mgd mgd mgd 1.1.1. Capital Cost ($) (based on $378,000 in 1969 for a 7.5 mgd plants with adjustment made for scale and inflation) . . . . . . . . . .

24,800 133,100 714,500 1.1.2. Annual Fixed Cost ($/ an num) (depreciation 4%, interest 10% maintenance 1.2%) . . .

3,770 20,230 108,600 1.1.3. Average fixed cost (cents/1000 gal) 10.33 5.54 2.98 1.1.4 Labour Requirement (man-hours/ 1000gal) . (based on $30.69 /day for a 7.5 mgd_plant at a rate of $6.11 per man-hour5 with adjustment made for scale) . . . ... . . .. . .......... 0.00170 0.001 05 0.00063 1.1.5. Labour Cost (cents/1000 gal) (based on a rate of $8.0/ man-hr.) . . 1.36 0.84 0.50 1.1.6. Lime Cost (cents/1000 gal) (based on a rate of 400 ppm and a cost of 0.89 cent/ lb) .

3.57 3.57 3.57 1.1.7. Power Cost (cents/1000 gal) (based on a usage of 0.06 KwH/1000 gal 0. 12 0. 12 and a rate of 2.0 cents/ KwH. _0~-~12~-~~

Average Lime treatment cost [cents/ 1000 gal]

15.38

10.07

7. 17 11

.2 Lime Mud Oewatering

0.1 1.2.1. Capital Cost($) (based on $110 ,840 mgd in 1969 for a 7.5 mgd plants with adju st ment made for scale and inflat ion .

7,247 1.2.2. Annual Fi xed Cost ($ / annum) Deprec iation 4% , interest 10% maintena nce 8.0% ) . . . . . . . . . . . .

1 ,594 1.2. 3. Average Fixed Cost (cents/ 1000 gal) 4.37 1.2. 4. Power Cost (cents/ 1000 gal) (based on a usage of 0.098 KwH / 1000 gal.5 and a rate of 2. 0 cents / KwH .

0.2 1.2.5. Labour Requirement (man-hr / 1000 gal) (based on $21,47 / day for a 7.~ mgd plant at a rat e of $6.11 1man-hr 0.0012 with adju stment mad e for scale) 1 .2.6. Labour Cost (cents/ 1000 gal ) (based on a rate of $8.0 l man-hr) 0.96 Average Lime Mu d Dewatering Cost (cents /1000 ~)......... . . . . . . .. .. . ...

5.~ 1 .3 Lime Mud Disposal (based on a sludge produ ct ion rate of 5.63 lb /1000 gal9 and a di spo sal cost of 0.02 0.11 cent/ lb).

Average total cost of lime treatment without recalclnatlon {cents/1000 gal]

1.0 mgd

10.0 mgd

38 ,900

208 ,230

8,558 2.34

45 ,810 1 .26

0.2

0.2

0.00073

0.00044

0.58

0.35

3.12

1.81

0.11

0.11

13. 30

9.09

0.1 mgd

3.1 Capital Cost ($) (based on $310 ,000 in 1969 for a 7 .5 mgd plant with adjustment made for scale and inflation) . .

22 ,000 3.2 Annual Fi xed Cost ($ / annum) Depreciation 4%, interest 10% and maintenance 1.0% ) 3,300 3.3 Average Fi xed Cost (cents / 1000 gal) . .... 9.04 3. 4 Labour Requirement (man-hr /1000 gal) (based on $4.63/ day for a 7.5 mgd plant at a rate of $6.11 1man-hr with adjustment 0.0003 made for scale) 3. 5 Labour cost (cent s/ 1000 gal) (based on a 0. 24 rat e of $8.0 1man-hr) . . ... .

3. 6 Power Cost (cent s/ 1000 gal) (based on a rat e of 0.67 KwH I 1000 gal , and a cost of 1.34 2 ce nts / KwH ) .

Average Total Cost for Ammonia Stripping [ cents/ 1000 gal) .

10.62

1.0 mgd

10.0 mgd

108,500

382 ,000

16,275 4.46

57 ,300 1.57

0.0001

0.000095

0.08

0.076

1.34

1.34

5.88

2.99

---------22 .83

2. With Recalclnatlon 2.1 Lime Treatment 2.1.1. Capital Cost($) (based on $318 ,000 in 1969 for a 7 .5 mgd plant5 with adjustment made for scale and 24 ,800 inflation) 2.1 .2. Annual Fixed Cost ($/annum) (depreciation 4% , interest 10 % and maintenance 1.2% ) .

3,770 2. 1.3. Average Fixed Cost (cents/ 1000 gal) 10.33 2.1.4. Labour Requirement (man-hr/ 1000 gal).

0.0017 2.1.5. Labour Cost (cents / 1000 gal).

1.36 2.1.6. Lime Cost (cents/1000 gal) (see 2. 3.8.) . . . . .............. nil 2. 1.7. Power Cost (cents/1000 gal) . . . .

0.12 Average Lime Treatment Cost [cents/1000 gel] .

2. 2 Lime Mud Dewatering Average Lime Mud Dewatering Cost (cents/1000 gal) (see 1.2) 2.3 Lime Mud Recalclnatlon 2.3.1. Capital Cost($) (based on $405 ,160 in 1969 for a 7.5 mgd plant5, with adjustment made for scale and inflati on . . . . .

2. 3.2 . Annual Fixed Cost ($/annum) (depreciation 4% , interest 10% and maintenance 2% ) . . .

2.3.3. Average Fixed Cost (cents/1000 gal) 2.3.4 . Power Cost (cents/1000 gal) (based on a rate of 0.07 KwH/1000 gal.5 andarateof2 .0centsKwH) .. .. .

2.3.5 . Fuel Cost (cents/1000 gal) (baseg on a rate of 0.35 therms/1000 gal. and a rate of 8 cents/therm) . . . .

2.3.6. Labour Requirement (man-hr /1000 gals) (based on $64 .36 / day for a 7.5 mgd~lant at a rate of $16 .11 Imanhour ) . . . . . . . . . . . . . . . . . . . . . . . . .

2. 3.7. Labour Cost (cents/1000 gal) (based on a rate of $8 .001 man-hr.

2. 3.8. Make Up Lime (cents/1000 gal) (based on a rate of 0.3 lb/1000 gal) and a cost of 0.89 cent/ lb) Average cost (cents / 1000 gal).

Average Total Cost of Lime Treatment with Recalcinatlon [cents/1000 gal).

12

3. Ammonia Stripping Column

11.81

5.53

133,100 714 ,500 20,230 5.54

108,600 2.98

0.00105 0.84

0.00063 0.50

nil 0.12

nil 0.12

6.50

3.60

3.12

1.81

26 ,490

142,176

761 ,530

4,238 11.61

22 ,748 6.23

121,845 3.34

0.14

0.14

0.14

2.8

2.8

2.8

0.0037

0.0028

0.0013

2.96

1.76

1.06

0.26 17 . 77

0.26 11.19

0.26 7.60

35 .11

20 .81

13.01

4 . Recarbonatlon and Clarification 4.1 Capital Cost ($) (based on $152,000 in 1969 for a 7.5 mgd plant with adjustment made for scale and inf lation) . ¡ 10,160 4. 2 Annual Fixed Cost ($/annum) (Depreciation 4%, interest 10% and maintenance 3. 0% ) .................. . ... 1,727 4.3 Average Fixed Cost (cents / 1000 gal) . . . . . 4. 73 4.4 Labour Requirement (man-hr / 1000 gal) (based on $16.87/day for a 7.5 mgd plant atarateof$6.11/man-hr.) ..... . . . . . . . 0.00096 4.5 Labour Cost (cents/1000 gal). (based on a rate of $8.001 man-hr.). . . . . . . . . . . . . . . . . . O. 77 4.6 Carbon dioxide cost (cents/1000 gal) (based on a rate of 0.8 lb/1000 gal and a cost of 11 cents/ lb) . . . . . . . . . . . . . . . . . . . .

8.8 4.7 Power Cost (cents / 1000 gallons) (based on a rate of 0.13 KwH / 1000 gal and a cost of 2 cents/ KwH) 0.26 Average Total Cost for Recarbonatlon without recalclnation [cents/1000 gallons] . . . . . . . . .

Average Total Cost for Recarbonatlon with recalcination [cents/1000 gallons] .

5. FIitration 5.1 Capital Cost ($) (based on $687 ,000 in 1969 for a 7.5 mgd plant with adjustment made fo r scale and inflation) ... . .. . ~ . . ..

5.2 Annual Fixed Cost ($/annum) (Depreciation 4% , interest 10% and maintenance 1.0% ) ..........

5.3 Average Fixed Cost (cents/1000 gal) . .

5.4 Power Cost (cents /1000 gal.) (based on a rate of 0.52 Kw H /1000 gal. and a cost of 2 cents/ KwH . . . . . . . . ....

5.5 Chlorinated Ferrous Sulphate Cost (cents/ 1000 gal .) (based on a rate of 0.2 lb/1000 gal . and a cost of 1.82 cents/ lb.) .

5. 6 Labour Requirement (man-hour/1000 gal .) (based on $24 .53/day for a 7.5 mgd plant at a rate of $6 .11 I man-hour with adjustment made for scale) .. . . . . . . . . . . . . . . . . .

5.7 Labour Cost (cents/1000 gallons) (based on a rate of $8 .001 man-hour)

54,470

191,000

9,260 2.54

32,470 0.89

0.00058

0.00035

0.46

0.28

8.8

8.8

0.26

0.26

14.56

12.06

10.23

5. 76

3.26

1.43

45,100

241 ,000 1,300 ,000

6,765 18.53

36 ,150 9.90

195,000 5.34

1.04

1.04

1.04

0.36

0.36

0.36

0.0014

0.0008

0.0005

1.12

0.64

0.40

21 .05

11.94

7.14

-----------

Average Total Cost of Filtration (cents/1000 gal.]

6. Chlorination 6.1 Capital Cost($) (based on $11 ,000 in 1969 for a 7 .5 mgd plant wit h adjustment made 21,650 3,840 for scale and inflation) .

719 6.2 Annual Fixed Cost ($ / annum) (Deprecia, tion 4% , interest 10% and maintenance 3 053 541 101 0.1% ) ..... .

0.15 0.08 6.3AverageFixedcost(cents/1000gal.) ... . . 0.28 6.4 Chlorine cost (cents/1000 gal.) (based on a rate of 5 ppm and a cost of 1O cents/ lb.)__o_._5___o_._5___o_.5_ Average Total Cost for Chlorination [cents/1000 gals.) .. .............

0.78

0.65

0.58

7. Activated Carbon Column 7 .1 Without Carbon Regeneration 7.1.1. Capital Cost($) (based on $632,000 in 1969 for a 7.5 mgd plant with adjustment made for scale and inflation) 7. 1.2. An nual Fixed Cost ($/annum) (Depreciation 4%, interest 10% and maintenance 1.0%) .... . .

7.1.3. Average fixed cost (cents/1000 gal) 7.1.4. Labour Requirement (man-hr/1000 gal) (based on $24 .53/day for a 7.5 mgd plant at a rate of $6.11 / man-hr. with adjustment mad e for scale) .

7.1.5. Labour Cost (cents/1000 gal. ) (based on a rate of $8.00/ man-hr) 7.1.6. Activated Carbon Cost (cents/1000 gal.) (based on a rate of 0.75 lb/1000 gal. and a cost of 22 cents/lb .) . ..

Average Tota l Cost for Carbon column without carbon regeneration [cents/1000 ga ls.) . .

0 .1 mgd

1.0 mgd

10.0 mgd

42, 840

221,850 1,193,400

6,426 17.61

33,280 9.12

179,010 4.90

0.0014

0.0008

0.0005

1.2

0.64

0.40

16.5

16.5

16.5

35.23

26.30

21 .81

69,000

375 ,000

12,564

67,662

3.44

1.85

0.0031

0.0019

2.48

1.52

0.1 neg

0.1 neg

0.1

0.1

7 .2 With Carbon Regeneration 7.2. 1. Capital Cost for carbon regeneration ($) (based on $199 ,000 in 1969 for a 7.5 mgd plant with adjustment made for scale and inflation) .. .. . . 13,000 7.2.2. Annual Fixed Cost ($/annum) (Depreciat ion 4%, interest 10% 2,340 and maintenance 4%) .

7.2.3. Average Fixed Cost (cents/1000 gal.) ....... .. ........... . ... . 6.41 7.2. 4. Labour Requ irement (man-hours/ 1000 gal) (based on $91.90/day for a 7.5 mgd plant at a rate of $6 .11 / man-hour with adjustment made for scale5) . ............. . ......... . 0.0052 7.2.5. Labour Cost (cent s/1000 gal. ) (based on a rate of $8.00/ man- hr.) 4.16 7.2.6. Fuel Cost (cents/1000 gal .) (based on a rate of 0.012 therm/1000 gal.

0.1 and a cost of 8 cents /therm) ... .. . . neg 7.2.7. Power Cost ........... .

7.2.8. Make Up Carbon (cents/1000 gallons) (based on a rate of 0.37 lb/ 1000 gallons and a cost of 2.68 0.1 cents/lb.)

Average Total cost of carbon regeneration [cents/1000gallons] Average Total Cost for Carbon Column with Carbon Regeneration [cents/1000 gallons]

2. It appears that , based on the ass umptions made, the processing cost for PCT plants would vary between 108 cents per 1000 gallons and 34 cent$ per 1000 gallons depending on the scale of operat ion and on whether recalcining of lime and/or regeneration of activated carbon is included in the system .

3. It should be noted that the acc uracy of the capital cost es!imates by the "Scale Factor" method is within + 25% only, and allowances should be made in in terpreting the above table and Fig. 1.

Furthermore it shou ld also be noted that the above results were obtained from a given set of ass umpti on of raw material prices , particularly the prices of carbo n dioxide, lim e, f uel and the cost of lime disposal. These prices vary depending on the locat ion of the plant and the quant ities of raw materials purchased . Thus, the decision as to whether to purchase lime and carbon dioxide or to insta ll a lime recalcination plant , and the decis ion as to whether to purchase activated carbon or to regenerate act ivated carbo n wil l depend on the local prices of lime, carbon dioxide , fuel and the act ivated carbon available .

From the above resu lts, it appears that in the case of a plant requ ired to employ all stages of purification, at the prices estimated for purchased lim e, carbon dioxide , fuel and the cost of lime disposal , the in stall atio n of lim e reca lc ination appears to be margina lly attract ive at higher capacities but marginally unattractive at lower capacities.

However if the cost of carbon dioxide can be reduced to, say 0.5 to 1 cent/lb , by generation and use of flue gas from fuel on site, lime reca lcination would not seem to be attractive.

Although the above proposit io n for generation and use of flue gas from fue l appears feasible , it has not been carried out, to our know ledge, at the present time, and hence has not been included in the tab le. However our calculation indicates that the total PCT Costs would be reduced to 91, 51 and 31 cents per 1000 gallons, a reduction large eno ugh to merit serious cons id erati on by potential users when evaluating comparati ve process economics.

1000

10 .77

6.12

3.57

29.50

15 .92

8.88

l/l

z

0

.J .J

<!

SUMMARY AND CONCLUSION 1. The above res ults have been convenient ly summarized in th e tab le and Figure.

D

0 0 0

---:::

â&#x20AC;˘

l/l I-

"'"

z

lcmrrt:/1000

"""'"

LL.I

10 0 u

~

Il/l

"--<..::: ' / / / '7'-7-

0

u _j

1-U

//

',

=

,., .....

IQ[/

' /~ ...,,_, / / / /

<!

I-

0

' / / ~~ ~ ~ V/

v~ vv -r-<l<:'.

Il!.l

D

]5.2]

a.so

<!

a.so

n:

UJ

>

<!

References 1 . " Physical Chemical Pilot Plant" L.

Ko larik et al. - Proceedi ngs of the Sixth AWWA Federal Convention , Melbourn e, May , 1974.

2 . "Process Selection and Cost of Advanced Wastewater Treatment in Relation to Secondary Effluents and Quality Requirements for Various Uses"L . R. J . Van Vuuren and M. R. Henze n - Progress in Water Tech nology, volume 1, Pergamon Press Inc . Sept. 1972.

0 01

1-0

100

CAPACITY- M.G .D.

3. "A dvanced Waste Water Treatment as Practiced at South Tahoe" Water Pollution Control Research Series , Water Quality Offi ce , 1971 . United States Enviro nment Protection Agency , Water Qua l ity Augu st, 1971.

4 . " Physico-chemical Systems for Direct Wastewater Treatment" W . J .

Weber Jr. Progress in Wat er Technology , volume 1, Pergamon Press In c. Sept. 1972.

Continued on Page 15 13

Construction and calibration of dissolved oxygen probes

by Peter Gebbie,* C. D. J. Fell & A.G. Fanet A small Mackereth type DO electrode may be fabricated in the laboratory for under $5 and when coupled to a chart recorder will prove indispensable for dynamic aeration studies [e.g. oxygen uptake rate in activated sludge].

Method of Construction A pi ece of lead foil (BDH, AR grade) approxi mately 10cm x 1cm with a tag at one end is perforated . Nylon ribbon which has been washed in acetone (to remove surface active constituents) is laid atop the lead foil and the strip wound tightly to form a porous cylinder. The cylinder should be insulated on the outside by a sing le .layer of ribbon.

+

Pb Foil & Nylon Wound Cylinder

,,,

About 20cm of 24 SWG silver wire is then tightly wound, closely spaced around the nylon over the central portion of the cylinder, and the two ends twisted together.

Flex is then soldered to the Pb tag (-ve) and the Ag wire ( + ve). A rapid setting 2 part epoxy resin (e.g . "Goa") is used to form an insulating bead over the two joints. "Silicone 500" (Selley's Chemicals, Bankstown, 2200) is used to form an outer layer over all parts except the Ag wire covered region. The chemical js best applied to the cylinder using a match stick.

The finished probe will resemble Fig. 1.

An electrolyte 1.08M in K 2 CO 3 and 0.5M KHCO 3 is prepared and the complete probe allowed to soak overnight .

The electrode is wiped dry with a tissue and the Ag wire immediately coated with a thin layer of silicone.

Alternative ly, the "Silicone 500" may be thinned using toluene and the thin solution quickly painted over the silver.

Care should be taken to avoid air bubb les in the paste. After drying the probe is then ready for use .

Calibration The calibration of the probe against air and oxygen saturated samples of water (at a known temperature) and deoxygenated water (by N 2 or Na SO 3 ) is useful. But often the region between zero DO and saturation in water is of interest. A check w ithin this range is helpful in assessing the linearity of electrode output and in construct ing a calibration curve .

The iodometric titration method (Winkler) may be used to determine the 'Chemical Engineer, William Boby & Co . \Aust.)

Pty. Ltd ., SCORESBY, Vic. 3179. tSenior Lecturer & Lecturer, respectively , School of Chemical Eng'g , U.N .S.W., KENSINGTON, N.S .W. 2033.

14

DO for a given sample of water at known temperatue as fo ll ows : 1. A sample of distilled/deionized water is partly deoxygenated using N 2 " aeration " , 2. the DO electrode is immersed in th e sample and the oltl,put as measured by a recorder (E .1. L.; Rustrac ; Heath " Servorecorder", etc .) is allowed to reach equilibrium . At a given value , say 30% of full scale deflection , the water sample is gently decanted into a BOD bottle and the DO determined by the Winkler technique , 3. per cent saturation at the known temperature can then be calculated for the oiven recorder value, 4. repeating this procedure at 2 or 3 more recorder values enables the calibration curve between zero & 100% saturation in water to be drawn,

Ag Wire

\..

5. a magnetic stirrer facilitates agitation and even transfer of oxygen from the atmosphere into the sample vessel (a 500ml beaker).

FIG. 1: Finished DO probe.

FIG 2 shows equipment required and FIG. 3 with TABLE 1 iUustrates a typical calibration curve obtained .

Thermometer

0 2 From Air

Recorder ~

T--fll-----1--------l.,__

D.O. Probe: To Recorder

Partially Deoxygenated Water

BOD Bottle

Winkler Titration & DO Determination

Magnetic Stirrer

FIG. 2: DO probe calibration equipment

MICROBIOLOGY OF WATER IN THE 1970's

100

.

E

80

"' C:

'6

z a:

60

'E

40

lll a:

20

a;

Lucy R. Alford B.Sc.*

0

0

40

20

80

60

100

% DO Saturation

FIG. 3: Typica l ca libration curve obtai ned for Ag/Pb, K 2 CO3 / KHCO 3 , Mackereth DO electrode coupled to a Heath EV20B " Servo-recorder".

As a check against technique, samp les of air sat urated and oxygen saturated d isti lled water may be titrated by the Winkler met hod and the va lue of DO obtain ed co mpared to that in the . l iterature, 1 2 at a given temperature .

Scale

T, •c

Average DO by DO at Wink ler Sat'n 2 3 mg/1 mg/1

77

13.5

10.44

10.2

100.0·

40 20 1.5

17 .5 17 .5 13.5

9.55 9 .55 10.44

4.5 2.3 0.0

47 .1 24.1 0 .0+

% Sat'n

• air saturated water • SO 2 • deox ygenated water Typi cal cali brat ion of DO TABLE electrode .

,:

References

1. "S tandard Methods for the Examination of Water & Wastewater", APHA , AWWA , W PCF, 11th Ed'n, APHA , N.Y. (1960) .

2. Eckenfe lder, W. W ., " Industria l Water Pollu tion Con tro l ", McGrawH ill , N .Y. ; (1966), 65.

References

5. " Comparative Cost of Tertiary Treatment Process", R. F. Westo n & R. F. peoples. Progress in Water Tec hno logy , volume 1 , Pergamon Press Inc . Se pt. 1972 .

6. "Advanced Was te Water Treatm ent " Cul p and Cu lp, Van Nos t ra nd Re inho ld Co., 1971.

7. "E valuation of Costs and Benefi ts of Nutrient Removal " Swedis h Tec hnica l Week in Australia, 1975.

8 . " Water Born e Was te" Supp leme nt to t he Chemica l Eng in eer , October, 1974.

9. " Dewatering Physica l-chemica l Sludges" Donald Dea n Adri an and James E. Smit h, Progress in Water Tec hno logy , volume 1. Pergamon Press. Inc. 1972.

The microbiology of water as practised in a control or investigational laboratory is a reasonably wide field. The aspect of monitoring for bacteriological quality of the water from a public health point of view only will be dealt with in this discussion.

• Miss Alford has just retired from the position of Water Supply Microbiologist of the Melbourne Metropolitan Board of Works and presented this paper to the Victorian Branch of the Association during 1975.

The practice of this aspect is based on the concept of use of indicator organisms to demonstrate po ll ution .

The indicator organisms used for this purpose are normal non -pathogenic inhabitants of the gut of the human and othe r warm blooded anima ls . The presence of t hese in a wate r is considered to be indicat ive of t he presence of sewage or faeca l matter and, therefore, the possibi lity of pat hoge nic organi sms also being present . Because of the ex iste nce of so many variables, pub lic hea lth practice is based not on probabil ity of infection bu t on the possibi lity of this occurring and in the case of potab le wate r placing the cons umer at risk .

With the indicator organisms now being used it is usual ly not poss ible to d ist ingu ish betwee n hu man and an im al be po ll ut ion . However, it m ust remembered that enteric bacteria l pathogens, in particu lar the Salmonella group of organisms, occur in an ima ls as we ll as man. The except ion is Sa lmone lla typhos us wh ich occ urs on ly in humans. The type distribution of Sa lmone llae in the commun ity at any one t ime is ref lected in the Sa lmone ll a pop ul at io n in do mest ic and farm animals and in scavengers either animal or bird which are present within and near the community . It must be remem be red t hat nat ive anim als in relati vely sec luded bush an d forest areas are host or carriers of some of the Salmone ll a group of organism , which are capab le of infecting man and caus in g ill ness.

There are a nu m ber of reasons for co unting organisms indicat ive of faeca l po llution in preference to iso lat ing and ide nt ifi cati on of th e pat hoge n. The Escherich ia co li presen t In a water may be counted wit hi n s ixteen to eighteen hours of receiving the sample in the laboratory.

Demonstrat io n of the ce rta in prese nce of th e pat hoge n may take seven o r eight days . Enu meration of Escherich ia co li in a samp le is re lative ly cheap whi le demo nst rat ion of

the pathogen requires an enrichment med ium , a se lective plating medium , media for biochemical tests and finally serological indentifit:ation . This is obviously a much more expensive procedure. Another re levant factor is that as the pathogens in the water will almost certainly be greatly outnumbered by normal intestinal organ is ms considerably larger samples wouid be necessary for demonstration of the pathogenic organisms than for an indicator organisms . Finally, it should be remembered that excret ion of the pat hogen and its entry into the water may be interm ittent , making the use of an indicator organism a necessity in monitoring the po ll ution of the water.

The ideal ind icator organism shou ld be present in large numbers in faeces , be solely excreta! in origin , should not grow outside the human and warm blooded anima l gut and shou ld have a die off rate similar to that of pathogens.

The requirement that the indicator organism should not mu ltip ly outs ide the huma n or an imal bbdy is unlikely to be met at al l t imes without enception. It is inconceivable that optimum temperatures and food sufficient for growth will not be• availab le within the enviro nment at least on some rare occas ion .

The coliform group of organisms are the most commonly used indicator group for potab le water. Escherichia co l i, a member of this group , is probably the most popular indicator organism because of the simple , speedy and re latively inexpensive methods ava ilable for its enumeration .

The coliform group of organisms may be identified, for the purposes of water m icrobiology , as gram negative, oxidase-negat ive, non-spo ring rods, capable of fermenting lactose with the production of acid and gas within 48 hours when inc ubated at 37°C . This group of organis ms, t hough they may have primari ly originated f rom faeces, are capable of growth in so il, rotting vegetation, etc ., so their presence especial ly in t he abse nce o f E. co li does not indi cate faeca l po llu t ion w itho ut a doubt and further invest igation is necessary to determinate their source .

The gro up, however, is the present 15

indicator chosen for determining the efficiency of chlorination . After successfu l chlorination there should be<1 coliforml100ml sample. Escherichia coli naturally may be defined in the same manner as the coli-form group but in addition is capable of fermenting lactose with the production of acid and gas at 44.5°C, capable of producing indole from a liquid medium containing tryptophan and is incapab le of using citrate as a so le source of carbon. It is of faecal origin almost w ithout except ion but as pointed out previously if optimum condit ions for growth occur there will be multiplication outside the animal body. Escherichia coli has been shown to mult iply in rotting vegetation such as pea silage or algae .

the faeca l streptococci group of organisms as an indicator group is that it encompasses a wide spectrum of organisms which may have different origins and differe_nt rates of survival.

The ubiquitous Streptococcus faecalis liquefacians may be present in appreciab le numbers in waters of good quality . It is generally accepted that good water with no pol lutional load may give a count of 100 faecal streptococc i per 100 m l. From th is it is apparent that the faeca l streptococci group is far from suitab le as an indicator of pollution for potable water.

Another disadvantage in the potable water field is that the incubation period for faecal streptococci is of the order of 48 hours.

Faeca l streptococci have been used as confirmatory indicators of pollution over a long period of time. In recent years new interest in them as indicator organisms has been aroused by the deve lopment of membrane filter methods of enumeration.Faecal streptococci may be defin !:''1 as gram + ve cocci, arranged in ,. ,-ir~ or short chains, which are bile resist c:. .lt and capable of growth at 45°C . They are cons idered to consist of Streptococcus faecalis (and its variants) , Streptococcus faecium, Streptococcus durans, Streptococcus bovis and equinis, all members of the Lancefield Group D Streptococci. The use of faecal streptococci as an indicator of po ll ution has been reported to have an advantage over the use of faecel co l iform or Escherichia co li in that the streptococci do not multip ly out of the animal gut . That it is, I consider, doubtful. The faecal streptococci are more demanding in the ir nutritional requirements than Escherichia coli and therefore it is quite reasonable to presume they wil l not be as prone to grow out of the normal intestinal environment . However, their multip l ication in waste water from vegetable processing was demonstrated in 1966 by Mundt . Some faeca l streptococc i such as a typical Streptococcus faeca lis and Streptococcus faeca lis var. liq uefacians have been iso lated from vegetation and insects .

The ratio of faecal coliform to faeca l streptococc i in a water sample has been recommended as an indication of whether the origin of the pollution is human or animal. The ratio faeca l coliform I faecal streptococc i in fresh raw domestic sewage or human excreta is¡ four or greater, whi le that for animal excreta is 0.7 or less. Care shou ld be taken in interpreting the ratio with waters as it does not rema in static for long after the po llu ting material has entered the water . The length of time for which valid conc lusions can be drawn is dependent on the composit ion of the water in which the po l lut ing materia l is d iluted , and the variety of organisms present in the original faecal pollut ion . One of the problems of using

Thoroughly tested standards method for the various indicator organisms or groups of organisms are available in a number of publications. The bacteriologica l examinat ion of water supp lies report No . 71 gives the Un ited Kingdom methods and po int of view . Standard methods of Water and Wastewater pub l ished in the U.S. gives the American methods and point of view .

The World Health Organisations' publication Standards for Drinking Waters (1971) expresses the views of experts in th is field from many countries.

16

When setting up a new laboratory or commencing an investigation it is adv isab le to remember that the most suitab le method and medium is dependent on the physical, chem ical and bacteriological content of the water to be tested. Both the bacteria l indicator level and the types and number of non-indicator organisms present in the water may have an influence on the efficiency of a method used. For instance membrane f ilters cannot be used for enumeration of indicator organisms in turbid water or waters with high background popu lat ions of non- indicator organ ism . So in setting up a laboratory or starting a new investigat ion certainly do you r reading etc. , and decide on methods and media for trial but remember to compare and test these in the laboratory on a variety of samples before completely deciding on the standard method to be used.

Even when one has, after thorough investigation set up a standard laboratory method , one of the constantly recurring tasks in any laboratory is the evaluation of new and improved methods as they become avai lable .

These are compared with those in c urrent use by comparing resu lts of an appreciab le number of samp les under varying cond itions. For the comparison of two mu ltiple tube dilution methods or a M .T.D. method with a membrane filter method it is recommended that results for at least thirty samples should be compared using at least five replicates for each sample.

Now to deal with present bacteriological standards for drinking water; Criteria for satisfactory bacteriological water quality are available in a number of publications : (1) The U.S . Public Health Service Standards published in 1962.

(2) The bacteriological examination of water supplies Report No . 71 1969 of U.K. (3) Standards for Drink ing Water W .H.O. 1971.

There is virtually no difference in the three standards. It could be contended that the U.K. standards are more realistic in that they allow occasional counts of up to 2 E.co lil100 ml.

However, there are conditions relating to such counts and one of them is that the count of 1-2 E.colil100 ml should not be associated with a coliform count of > 31100 ml. These standards have been developed over the years by teams of experts , and eac h new development has been based on retrospective ev idence in an effort to overcome past fai lures . The downward trend of enteric disease associated with water treatment is universal and unmistakable and is a confirmation of the success of application of water qua lity standards .

The Standards of Drinking Water published byW .H .O. give conditions of surveillance of a water supply, which are implicit in the use of their bacteriological criteria. Surveillance is a very important part of water supply qual ity attainment and if the conditions stated there were always fu lfil led many prob lems wou ld be avo ided . The conditions inc lude a thorough examinat ion of the whole system, from source through to the distribution , at regular intervals and under a variety of weather and operational condit ions . Samples should be collected and examined with or after these in:.pections . An important point to remember is if inspection indicates that the water being distributed is open to po llution immediate action should be taken without waiting for and irrespect ive of results of the bacteria l exam inat ion. The reason for this is that if po ll ution is occurring it may be intermittent.

A report in 1975 from the Environmenta l Protection Agency in Washing ton regarding the Safe Drinkin g Water Act which was signed into law in December 1974 gave some interest ing points and much of it bears direct quoting. It was stated that the standards would become effective in December 1976 and would app ly to most of the United States of America's 240 ,000 pub li c water supp ly systems .

The standards are based on the 1962 Pub lic Health Serv ice recommended standards .

Extracts from the information sheet read as follows: "Turbidity , or murkiness , of drinking water is also covered in the proposed

standards. Turbidity often interferes with the disinfection of water supplies and the maintenance of effective disinfectant levels throughout a water distribution system. High turbidity also serves as an indicator of the possible presence of microbiological organisms .

Specified max imum levels for microbiological contaminants are based on measures of faecal coliform bacteria, although other organisms also will be control led. To assist smal I water supply systems, measurement of chlorine remaining in the water following treatment may be used to determine compliance with the standard .

The standards contain sampling requirements to help insure continuous compliance. The number of samples required each month varies as to the size of the population served by the system. Laboratories analysing the samples must be certified to insure the validity of the analyses performed .

Requirements for reporting the results ¡ of sample analysis are also included .

The public must be notified in the event if a system does not comply with the standards or perform proper monitoring. In such cases the water supply must also notify the State and EPA. Maximum Microbiological Contaminant Levels Two methods may be used to comply with levels .

(1) When membrane filter technique used (a) coliform densities shall not exceed one per 100 milliliters as an arithmetic mean of all samples examined per month; and either (i) tour per 100 milliliters in more than one standard sample when less than 20 are examined per month ; or (ii) four per 100 milliliters in more than five percent of the standard samples when 20 or more are examined per month .

(2) (i) When fermentation tube method used and 10 milliliter standard portions , coliforms shall not be present in more than 10 per cent of the portions in any month ; and either A . Three or more portions in one sample when less than 20 samples are examined per month; or B. Three or more portions in more than five percent of the samples if 20 or more samples are examined per month. (ii) When fermentation tube method used and 100 milliliter standard portions (1) coli forms shal I not be present in more than 60 per cent of portions in any month ; and either A. Five or more portions in more than one sample when less than five samples are examined; or

B. Five or more portions in more than 20 percent of samples when five samples or more are examined .

Supplier of water shall provide water, in which there shall be no greater than 500 organisms per one milliliter as determined by the standard bacterial plat count .

Maximum Contaminant Level of turbidity The level at representative entry point(s) to the distribution system is one turbidity unit (TU) except that five or fewer turbidity units may be al lowed if supplier can demonstrate to State that higher turbidity does not : (a) Interfere with disinfection; (b) Prevent maintenance of an effective disinfectant agent through the distribution system; and (c) Interfere with microbiological determinations. " In a laboratory monitoring bacteriological water quality it is necesary, despite the amount of repetitive work to retain a questioning outlook. The microbiologist supervising routine laboratory work should be fully qualified and an alert and conscientious worker. If a fully qualified supervisor is not available the laboratory should be visited at frequent intervals by a fully qualified microbiologist. In a potable water laboratory or in laboratories monitoring water quality for other than potable ¡water it is preferable that the staff co llecting samples should work under the direction of the microbiologist in charge . If this cannot be arranged the samplers should be trained by the microbiologist and there should be continuing contact between the sampling and laboratory staff.

Ideally, in my opinion, the technical staff in a routine water microbiological laboratory should consist of fully qualified graduates, technical officers and technica l assistants. The technical officers should have at least one year's formal microbiological training . The technical assistants should have passed the Higher School Certificate in scientific subjects and preferably should be studying part time. The ratio of each type of staff should be two graduates, three technical officers and 2 or 3 technical assistants.

Overseas Visits In 1974 I visited some laboratories overseas to get some leads on automation. In london , Dr. Burman, head of the Metropolitan Water Board Laboratories was of course interested in automation but considered there were still so many unso lved problems regarding automation in microbiology that th is was the province of a research institute. He considered it difficult to ju stify the expense in a water supply labo ratory.

He was, at that time, more concerned about new materials which were being produced by the plastics industry and

being presented for use in the water supply industry . In 1967 and 68 the Metropolitan Water Board Laboratory demonstrated that a number of materials and fittings common ly used in contact with water promoted the growth of fungi and actinomycetes and in this way could have led to tastes and odours in the water. Dr Burman was still developing methods for assessing the effect of the materials on the water in contact with them. They can effect colour, turbidity , taste, odour, or they may be toxic or they may provide nutrient for bacteriological growth .

To me this appears to be a field in which we, in Australia, could be well advised to show an interest .

The Metropolitan Water Board in London have been building up virological information since the early 1960's. Among many other investigations they examined the water passing into supply at the rate of about 100 one- litre samples each year. Since they commenced to do this in the late 60's, all results for these litre samples had been negative . They employed the alginate ultra filter method for examinations of the samples .

The Public Health Engineering section of the Department of Civi l Engineering at the University of Newcastle on Tyne, had published papers which suggested they were interested in developing quicker and easier methods of enumerating indicator organisms. For this reason I paid them a visit. Dr Pugsley who was the senior worker on a project on the use of fluorescent antibody techniques for enumeration of faecal streptococci considered that he could not recom mend it as a practical routine method for examination of water as it was too costly. t Lillian Evison felt hopeful that Bifidobacterium might be successfully used as an indicator of pollution especially in tropical countries. She, incidentally, was critical of faecal streptococci as in her experiments they died off too quickly to be, she considered, suitable as indicators of faecal po llution.

From England I went to the United States. Whilst there, I visited Cincinnati and Chicago. In Cincinnati I met Mr Geldreich and his staff of the Water Supply Research Laboratory of the National Environmental Research Centre . I was most interested in all that ~as going on there and was made most welcome . These laboratories and their staff seemed to have two functions. The first they called the major research objective , this being divided into four different programmes . As well as proceed ing with these research projects they appeared to act as a central advisory centre and also produced reviews on various subjects concerned with the microbiology of water.

17

The first project was concerned with standard methods , etc ., for the 14th Edition of Standard Methods of Examination of Water and Wastewater.

Among the recommendations put forward was the inclusion of a standard plate count in the new criteria . The plate count at 37°C of finished water was to be not greater than 500 / ml.

Incubation was to be 48 hours , NOT 24 hours . They considered this plate count limitation would 1 . Provide a method for monitoring for changes in bacteriologic quality in storag e reservoirs and in the distribution system .

2. Indirectly limit the occurrence of Pseudomones , Flavobacterium and other secondary pathogenic invaders that could pose a health risk in the hospital environment.

3. Reduce the problems in detection of low densities of total coliforms due to interference by non coliform bacteria .

4·. Monitor the effectiveness of chlorine throughout the distribution network and provide a warning of filter effluent quality deterioration and the coliform breakoccurrence of through , and 5. Indicate the existence of sediment accumulation in the distribution network that provides a protective habitat for the general coliform population .

Dr Geldreich and his group were concerned with the lack of uniformity of dehydrated med ia and membrane filters. As regards membranes , they considered that these not only varied from one manufacturer to another, but from batch to batch . They had hopes that in time both dehydrated media and membranes will be required to be standardised . They had taken action to this end .

They had developed , and at the time I was there were refining and making final checks on a rapid enumeration of faecal coliform which gave a result within seven hours . They used a lightly buffered agar medium w ith a doub le indicator system for detecting the early production of acid from lactose. The temperature of incubation chosen was 41.5°C. This rapid test could be of value for quick measurement of water quality in an emergency .

Dr Ron Reasoner who was completing this project was also investigating a more rapid radiometric method. A reasonable amount of work has been published in this fie ld in recent years .

He was attempting to quant ify the faecal col iform present using an Endo based medium with a Carbon 14 label led glucose and/or formate . Lactose labelled with C14 was not available . A Packard Liquid Scintillation Photometer was being used .

The current problem at that time was that the uninoculated medium gave an apparent reading. The materials and 18

equipment for th is work were very expensive and would not be suitable for any but big concerns . This could conceivably be automated if the " hang ups" could be taken out of it.

Another field which interests the E.P.A . is deterioration of microbiological quality throughout the distribution . They are concerned with regrowth and wanted to investigate the debris in mains and dead -end mains . This investigation had not been commenced . Ray Taylor had conducted a survey on the effect of new and repaired mains in a distribut ion system . They had surveyed th e disinfectants in use , in the treatment of these mains before putting into consumption , and found chlorine dosage was considered to be the most satisfactory method in use amongst the water companies supplying the information.

Fai lu re to thoroughly clean mains before ch lorination was listed as one of the prob lems encountered . This , in my opinion , would be the biggest problem and to this comment I would add the necessity to keep the main free of extraneous matter while laying it . They were very keen on the theory of Hutchinson of Water Research Association in England that persistance of presence of the coliform group of organism in a main after chlorination could be due to growth in the lubricant used in the joining of pipes . The growth of organisms occurred in any dead space between the spigot and socket.

There was a team of four senior virologists at the laboratory. The Chief , Dr Berg was absent. They were concerned with developing methods of detecting viral levels in water. They were comparing .methods of filtering large volumes of water, say up to 100 gallons or 500 litres and determining viral levels in them . Their hope was that they may be able to set up parameters for drinking and bathing waters and relate these to the epidem iological data.

The group had already demonstrated in a number of samples of satisfactorily treated water that viruses were absent from five litres samples when the coliform content was >1 /100 ml or 1 / 100 ml in a similar five litre sample of a wat er. Th e actual laboratory for viral analysis of treated water, that is, drinking water, was completely isolated and entry into it restricted.

The water supply research laboratories of the E. P.A. also had t he respons ibility of evaluating those laboratories, w ithin their State , which dealt with the microbiology of water.

The E.P.A . apparently had one water laboratory evaluation officer in each State . These officers checked al I aspects of work including sampling, equipment , media , techniques, records and finally, the use made of

accumulated data. They reported that the usual weak point in the chain was the lack of any action following consideration of the accumulated data.

This did not surprise me . The publication called the Evaluation of Water Laboratories last published by the U.S. Department of Health, Education and Welfare in 1966, was being completely rewritten prior to republication .

So back to Chicago and an unscheduled half-day visit to the bacteriological laboratories of the Water Treatment Plant on Lake Michigan . Because of lack of time , I was unable to see the plant itself.

However, I found myself with a group con cerned with the routine examination of water and felt very much at home.

The laboratory was fa irl y new, well equipped and appeared pleasant to work in . All the staff of eighteen, with the exception of the media preparation staff, were ful ly qualifi ed. Dr Gin sberg who is in charge of the laboratory briefly exp lained the vital statistics of the water treatment plant.

Two treatment plants supplied an average of 1000 million gallons a day to 4 ½ million people in Chicago and suburbs . The water was sampled and checked bacteriologically from the supply through the treatment plant , this at 4 and 8 hourly interva ls, and then forty samples were collected daily in the distribution system.

Each regular sampl in g po in t in the distribution was sampled once every two days . A complete samp lin g of the plant and d istribution was carried out on a Saturday and samples ,were examined as usual.

Samples through the treatment plant only were collected on a Sunday and these were held and examined on ~onday . A number of investigational and developmental projects were in progress in the laboratory .

An investigation into the use of f luorescent ant ibody techniques in the enumeration of faecal coliform and faeca l streptococc i on membrane filters was in progress. The method was extreme ly simple and consisted of f il tering through a black filter, all ow in g this to stand -at a temperature of 70°F. for ½ hour, then washing with fluorescent antisera, rinsing twice and mounting. Dr Ginsberg considered that something may be achieved with faecal streptococci in the form of a presence absence type of test. Regrettab ly his staff were less hopeful.

The last mention of potable water on my trip occurred on a day trip around the Island from Honolulu. The driver and guide in the bus said as we climbed up the mountains that the water supp ly to Honolulu orig in ated from the slopes and was therefore "one of the best water supplies in the world " , which needless to say made me think of Melbourne and home .

NEW FLOTATION EQUIPMENT

PRODUCTS,PROJECTS AND PERSONALITIES E.C. OF N.S.W. AGAIN ORDER BOILED WATER CHEMICAL CONTROL INSTRUMENTATION FROM KENT. Kent lmitruments (Australla) Awarded Contracts Totalllng $A1 Milllon For Equipment to be Installed on New Generating Units at Vales Point and Wallerawang Power Stations.

Envirotech Australia Pty . Ltd. has announced a new induced air flotation system to be known as the Depurator.

The compact new flotation system is skid mounted and complete with chemical feed tank and dosing pump.

Standard units are offered with nominal capacities between 40 and 4,000 gpm . The flotator utilises four cells in series, each fitted with a nozzle device for inducing and dispersing gas bubbles into the wastewater. The new system is a development of the standard Depurator which has been widely used in the U.S .A. for many years in the removal and sometimes recovery of oil, fats, grease and suspended solids from process and wastewaters . in some applications the new machine has been successful in removing in excess of 90% of the BOD load .

The boiler water chemical contro l equipment being supplied by Kent comprises:Sample-extraction and -conditioning equipment Chemica l analysis instrumentat ion Boiler water chemical injection plant Sample-extraction and -conditioning equipment To provide the analysis instrumentation with samples from various points in the boiler water system of the power station, Kent are providing specialised boiler-water sample-conditioning equipment including Kent contra-flow cooling coi ls, Kent MK II pressure-reducing and flowregulating va lves, cat ion- and anion- exchange columns as well as other ancillary items such as sample rate of flow indicators , isolating valves, draining, cooling water services, etc. Samples at pressures up to 19.5MPa (2825 lbf / in) are reduced to a pressure a litt le above atmospheric for app lication to the various analysers by the MK II pressure-reducing and flow-regulating valve designed and manufactured in Australia by Kent.

Analytical instrumentation The analytical instrumentation being supplied by Kent includes instruments and sensors for the measurement of :Electrolytic conductivity Dissolved oxygen pH Hydrazine Sodium Ammonia Copper Iron On- line determinations of the leve l of iron, copper, ammonia. silica . etc .. in the bo iler water are oerformed by a Technicon Auto-Ana lyser.

Other analytical instruments be ing supp lied by Kent inc lude an E.I.L. Model 8000 series se lective-ion mon itor for the determinat ion of sodium leve ls and a Kent-Cambridge Mark IV hydrazine analyser. In addition, for Vales Point Power Station only, Kent will be supply ing an atomic-absorbtion spectrophotometer for the determination of levels of various meta ls in the parts per bil lion range in the bo i ler water.

LOWER COST, HIGHER CAPACITY ' DSM SCREENS Dorr-Oliver have revised the design of their well -known DSM (sieve-bend) screens to promote even greater capacity and lower product moisture. â&#x20AC;˘ The newly designed DSM Screens are built as stationary units employing a concave wedge-bar type screen with efficient provisions for introducing the feed at the proper velocity and withdrawing undersize and oversize products.

The photograph shows a 45° , 2400 mm wide gravity fed screen destined for the sugar industry.

Boller Water Chemical-Injection Plant At both Wallerawang and Va les Po int Power Stat ions Kent will also be supplying the Chem ical Injection Plant. This inc ludes the dosing- and transfer-pumps and associated controls , the chemical storage tanks and the chemical injection pipework, va lves , etc . Th is plant provides automatic dosing of the boiler water with aqueous ammon ia using variable-speed/ variable-stroke dosing pumps - the speed being set in proport ion to the condensate flow whi lst the stroke is set according to the dev iation from the control set po int .

The Chemical Injection Plant also includes facilities for the manual injection of both hydrazine and high-pressure boiler water chemicals.

The equipment being supp lied for Va les Point Power Stat ion also includes a plant for the production of a 5% aqueous ammon ia solution from bu lk anhydrous ammonia.

19

" The comp lete order of more than 400 pipe lengths was del ivered to the site in Narrabri just two days after the Council 's ca ll , and before al l the necessary trenches had been comp leted," Mr. Ganno n sa id .

James Hard ie contin ued to supp ly spec ial cast-iron fittings on an overn ight basis as requested by the council.

Counc il construction teams worked almost 24 hours a day, despite more heavy ra in , to comp lete the connection in six days.

Mr. J . Robertson, Narrabri Counc il Health Surveyor, said the job had been ach ieved in "really good t ime".

NEW QUEENSLAND MANAGER FOR HAWKER SIDDELEY BRUSH Mr. Nick Cameron has been appointed Queensland Manager for Hawker Siddeley Brush Pty. Limited .

Mr. Cameron has been with the Hawker Siddeley group sin ce 1959. He came to Australia in 1966 (to set up a licensing agreeme nt to build locomoti ves in Syd ney) and transferred to the Australian company in 1968. For the past four years he has been Ass istant Manager of Hawker Siddeley Brush Pty. Limited's West Australian branch .

His experience covers all the company products in cludin g . power generation equ ipm ent, electrical equ ipm ent and environmental systems. He has ju st returned from overseas after spe nding two and a half months vi s iti ng associate companies in the United Kin gdom, United States, Canada and Europe.

He will be responsib le for Hawker Sidde ley Brus h operations in Queensland and Papua New Guinea.

FAST TRANSPORT OPERATION PREVENTS POLLUTION An emergency transport operation mounted in February, 1976 by the largest asbestos cement product manufacturer in Australia helped avoid a seriou s health risk to towns in the north -west of N.S.W .

James Hardie and Coy. Pty . Limited supp lied more than 1500 metres of pipe virtually overnight to Narrabri after f loods had washed away a vital link in the town's sewerage system.

A log jam on the swo llen Narrabri Creek carried away a 150-metre sectio n of the system - a suspens ion bridge erected to carry the lin e while construction of a new bridge was in progress.

Water from the Narrabri Creek, a tributary of the Darlin g River system , flows through many towns in the north-west.

Flood conditions made replacement of the original suspe nsion bridge and link impossible.

NEW MANAGER FOR ENVIROTECH WESTERN AUSTRALIA Mr. Max G. Rogers has been appo inted as Manager, Western Australia and w ill assume full responsibility for all Envirotech Australia Pty. Limi ted act iviti es in Western Austra li a. Mr. Rogers is a dip/ornate in Applied Chemistry and Management from the Royal Melbourne Institute of Technology and has been involved in the chem ical and minera ls processing indu stries since 1955.

Envirotech Australia Pty . Limited is joint ly owned by Envirotech Corporation, U.S.A. and Johns & Waygood Perry Engineering Limited , Melbourne. This joint ow nersh ip arrangement gives the Com pan y access to Johns-Perry manu factur ing facilities throughout Austra lia, and co ntinued access to Env irotech U.S.A. for latest technology and research and development. '

WATER TREATMENT EXPERT VISITS AUSTRALIA

A diversion lin e for the flo od damaged Narrabri sewerage system was taken across the Narrabri creek via an existing road bridge while the water was still near i ts peak.

20

Mr. Alistair Stratto n, Director, Chemical Engineering , of Hawker Siddeley Water Engineering Ltd. of the UK visited Australia during February . He looked at developm ents in the water an d wastewater treatment busines and at the act ivities of Hawker Sid de ley Water Engineering (Au strali a) which operates as a division of Hawker Siddel ey Brush Pty. Limited .

Mr. Stratto n visited Perth, Adelaide, Melbourne, Sydney , Brisbane and country areas to study Australian conditions in re lation to wate r and wastewater treatment. He presented a paper on current and future trends in the acti vated sludge process, at the February Victo rian Branch meeting . co ntinu ed next page)

PORT PHILLIP BAY PROTECTED

BY NEW SYSTEM For generations wastes from the toilet block and kiosk on Melbourne's St. Kilda Pier have pol luted Port Phill ip Bay, discharging direct ly into the water within sight of nearby swimming beaches .

A new system adopted by the Victorian Government Public Works Department has now overcome the prob lem . Bay pollution from this source has stopped.

Known as the 'Electrolux Vacuum System', it basically comprises special toilets connected by pvc pipes to a storage tank. The pipes are held under vacuum by an automatical ly operated electric pump. As the toilet is operated, air is admitted to the system and as it tries to fill the vacuum, the wastes are carried to a large capacity storage tank . It is pumped from the tank into the Melbourne Metropolitan Board of Works ' mains . St . Ki Ida City Council cooperated w ith the Public Works Department in the project.

The Me lbourne Harbour Trust has also been active in pollution contro l on the bay , being responsible for the installation of three earlier Electrolux Vacuum Systems at South Wharf , Station Pier and Victoria Dock.

Env ironmenta l Protection Authority approva l was g iven for the project following the recent construction of a new concrete pier built to replace the old wooden one . A conventional system could have been installed , but because of the pier's considerab le length between the toilet block and the MMBW mains , expensive pumping stations would have been needed.

The vacuum system , whi le also disc harg ing into MMBW mains , avoids the need for pumping stations of this nature.

The overall $15 ,000 cost for the installation was considerably less than wou ld have been incurred with a conventiona l system.

And, because the new system is operated under vacuum it has an additional unique feature. A simple connection to the main wi ll al low extens ion of the scheme to accommodate ship-to-shore sewage d isposal from sma ll boats moored by the pier.

Further information: Mr. J . J. Chi ld, Manager, Environme nta l Systems Div ision, Elect ro lu x Pty. Ltd. , 87 A lexandra Avenue, South Yarra , Vic . 3141 . Phone: 24-1261 .

NEW DENITRIFICATION FILTER SYSTEM UNDER WAY A $1.5 mill ion contract has been received by Dravo Corporat ion, Pittsburgh, for design and procurement serv ices on a denI trn Icat Ion t il ter system at the Ga in esv ill e, Fla. , Kanapaha Waste Water Treatment Plant.

The filter system will employ the Dravo-patented Denite process for bio logica l denitrification and suspended so lids remova l. The Gai nesvi lle project w ill be the f irst time the Denite process has been used in a major metropolitan waste water treatment plant .

The de ni trification f il ter system wi ll be capab le of handli ng seven m il lion ga ll ons of waste water per day, peaking at 17.5 million gal lons per day , and reducing nitrate-nitrification leve ls to an average of three mi lligrams per litre and suspended so lids to an average of 10 milli grams per litre .

The contract was awarded by Norflor Construction Corp., Orlando, sponsor of a joint venture with Sunsh ine Peninsula , Inc .

Dravo has already begun work on the project and is current ly preparing detail drawings and procuring equ ipment.

The company 's engineers have also completed a pi lot Denite process test prog ramme to determ ine sys tem requ irements.

The Denite process ut il ises conventional deep bed filter hardware, including special high density concrete block filter bottom, si l ica sand media and automatic contro ls .

Further deta il s are avai lab le from Dravo's A ustral ian company , Dravo Pty. Ltd . at St. Leonards , Sydney.

Re leased by: Oravo Pty. Ltd .

Thro ugh: Er ic Wh ite Associates Pty. Ltd. For further information: Diana Shaw - 20271 .

PATENTS A reactor for wet oxidation disposal of waste matter in suspension has been patented. The reactor is essentially a horizonta l, cylindrical autoclave , divided into several compartments by vertical partit ions. An inlet l ine de li vers liquid into the first of these compartments. Each compartment contains a top entry , high speed rotary shaft, with two vertically spaced agitators , and a bottom entry oxygen/ air inlet nozzle. The nozz le is directed onto the underside of the lower agitator and disperses fine bubbles into the liquid.

Transfer pipes aid in moving the liquid between compartments and in discharging it from the final chamber via separate vapor and liquid outlets . In the disposal of w¡aste organic matter, BOD and COD values are reduced by 80 to 90%. Because of the intense dispersal of fine oxygenation bubbles, the process performs we l l at lower temperatures than previous wet oxidation processes.

French Patent FR 2244-722 . May 23, 1975. Derwent French Patents Abstracts , W(26): 04 , August, 1975 . .., A cylindrical filter tank , covered with a filtering fabric, is arranged in a reservoir. In this patented method, sewage enters the chamber of the reservoir through an inlet pipe. A cylindrical supporting plate surrounds the filtration tank , and another cylindrical support plate is arranged inside the chamber. Sewage water flows up the passage and through the filter into the space . A ir enters through openings and generates a flow of bubbles; this produces a pressure difference between the fluid containing bubbles and the fluid w ithout bubbles. The pressure difference removes the so lid matter adhering to the f iltering fabric and prevents c logg in g.

An overflow pipe then receives the filtered water . Any smal l particles wh ich pass through the filter are evacuated from the con ica l po rt ion by an air pump. Co nce ntrated so lid matter and residue from the sewage is evacuated for further treatment. Because the flow of bubbles prevents any blockin~ of the fi lter fabric, removal of the suspended sol id matter is effic ient and continuous fi ltrat ion is possib le.

French Patent FR 2247-270 . June 13, 1975. Derwent French Patents Abstracts, W(29): D2-D3, August, 1975.

A patent has bee n granted to a process and equipment for treating wastes by a combined activated sludge and biologica l filter bed . Sewage is treated in a tank containing the means to maintain a submerged biolog ica l fi lter bed zone containing finely divided , particu late fi lter media. The tank further contains equipment to maintain an activated sludge zone in the tank in an upstream fluid flow relationship to the submerged bio log ica l f il ter bed zone. Baff les d ivide the tank into several compartments. These baff~s extend through the activated sludge zone and partially into the biological filter bed zone. When the apparatus is in use, the fine ly div ided part icu late fi lter media can be recircu lated and backwashed and the activated sludge zone aerated . Sewage is fed into the first compartment and treated effluent is removed from the act ivated slu dge zone of the last compartment.

Canadian Patent 972,877 . August 12, 1975. Patent Off ice Record , 103(32): 84, August, 1975.

I.A.W.P.R. SYDNEY, 17-22 OCTOBER, 1976

POST CONFERENCE COURSES AT MELBOURNE COURSE I Treatme nt and Disposal of Wastewater by Low Cost Methods - 23rd-24th October.

COURSE II Unit Processes in Wastewater Treatment October.

COURSE Ill Advanced Treatment COURSE IV Bio log ica l Monitoring -

23rd -24th

25th October.

- - - - - -- - - - - - - - - - - - - - --- -25th-26th October.

21

17-22 OCTOBER, 1976.

The Efficacy of an Equalisation Pond in a Water Reclamation System (South Africa) The integration of Wastewater Treatment with Water Reclamation (South Africa) Disposal of Sludge Using Solid Wastes as Fuel (USA) Scale-up Methodology for Surface Aerated Reactors (Canada) (Hungary) Investigations into the Lime i;>recipitation of Raw Munici'pal Wastewater (USA) Simulation of Design-Storms with Probable Distributions (Germany) Fellmongery Waste Treatment - Comparison of Cost and Degree of Treatment (New Zealand) Calcium Carbonate and Magnesium Hydroxide-Solubility Product Values (South Africa) The Significance of Stormwater Runoff in an Urbanising Watershed (USA) Treatment Alternatives for Wastewaters from the Tapioca Starch Industry (Thailand)

IAWPR CONFERENCE TECHNICAL PROGRAMME Spray Irrigation with Wastewater (Israel) Great Lakes Water Qual ity Agreement (Canada) Comparative Evaluation of Commercial Polyelectrolytes (Canada) Virus Retention by Soil (India) Localised Destratification of Large Reservoirs to Control Discharge Temperatures (Australia) Treatment of Chlorinated Hydrocarbons Wastewater by Activated Carbon (Israel) The removal of Viruses by Slow Sand Filtration (Great Britain) A Mu ltid imensional Analysis of the Results of the French 1971 Surface Water Quality Network Control in the River Basin "Seine-Normandie" (France) Remova l of Polynuc lear Aromatic Hydrocarbons from Water Durin g Chl orination (Great Britain) Virus Remova l in Activated-Sludge Sewage Treatment (India) Hydrodynamics of Bubble Plumes and Oxygen Absorption in Stratified Impoundments (Saudi Arabia) (USA) Chromium Remova l with Act ivated Carbon (USA) Nitrogen , Phosphate and Virus Removal from Sewage Water During Land Filtration (USA) Environmental Consequences of Groundwater Contamination (USA) Sed imentat ion of Dispersed Oi l in Surface Waters (Switzerland) Faecal Coliforms and Faecal Streptocci: A Statistical Comparison (Great Britain) Pi lot Plant Evo lution of Various Pollutants During Artificial Recharge (France) Two- layer Time-dependent Model - Pollutant Assessment and Control in a Short Stratified Estuary (Australia) The Effect of Ozone Bubbles on Disinfection (USA) Hydrochem ical Effects of Waste Perco lation on Groundwater (Austra l ia) Preliminary Design of Ocean Outfall at Sydney: Protection of Bathing Waters (Australia) Workshop - Current and Future Marine Pollution Problems Workshop - Ultimate Disposa l of Sludges, Toxic Wastes and Strong Organic Liquors Dynamic Nature of Nitrifying Biological Suspended Growth Systems (Canada) Continuous Gravity Thickening of Sludges (USA) Disso lved-Air Flotat ion in Act ivated Sludge (South Africa) Design of a Nitrifying Activated Sludge Process with the Aid of Dynamic Simulation (Switzerland) Dewatering Properties of Lime Stabilised Sewage Sludges (Norway) Variab il ity of Temperature and other Process Parameters A Time Series Ana lysis Sludge Plant Data (Canada) An Integrated Pollution Control System (USA) (Israel) Studies on Pyrolysis Process of Sewage Sludge (Japan) Comprehensive Temperature Mode l for Aerated Biological Systems (USA) â&#x20AC;˘ Design Approach for effluent Variability Removal in Wastewater Treatment Systems (USA) Combined Disposal of Sewage Sludge and Solid Wastes by the Pyrolytic Process (USA)

Advanced Wastewater Treatment by Chemical Precipitation with Lime and Ammonia Stripping in Ponds (Israel) Prevention and Protection of Sewage Systems Against Sulphide Attack (Singapore) Process Design Investigations for Alaska Pulp Mill Wastewater Treatment (USA) Improvement of Tertiary Filtration Efficiency by Upgrading Biological Activity (France) The Forecasting of Sulphide Build-up Rates in Sewers (USA) Measurement and Treatment of Oil and Grease in Petroleum and Petrochemical Wastewaters (USA) Recirculation Ponds - Pilot Plant and Field Studies (Israel) Current Status of Research in Automation of Wastewater Treatment (USA) Pollution Control Regulations and Monitoring Technology: A review of Research and Development from the Pulp and Paper Industry (Canada) Seepage from Oxidation Ponds (Israel) A Comparison of Pure Oxygen and Diffused Air Digestion of Waste Activated Sludge (Canada) Biomonitoring with Fish: An Aid to Industrial Effluent and Surface Water Quality Control (South Africa) An Integrated High Rate Pond-Algae Harvesting System (Australia) The Dynamic Behaviour of an Anaerobiq Digester (South Africa) The Use of Ozone Induced Chemiluminescence in Water Quality Monitoring (Australia) Workshop - Water Resources Quality Management Workshop - Land Treatment ~ Development of a Rapid Fish Toxicity Test Utilising a Freeze Concentration Technique for Routine Petroleum Refinery Wastewater Monitoring (Canada) Removal of Organics in Sewage ancl Secondary Effluent by Reverse Osmosis (USA) ~ Theory and Design of High-Rate Plastic Media Trickling Filters (Poland) Compounds Toxic to Fish in Pulp Mill Waste Streams (Canada) Series Intermittent Sand Filtration to Upgrade Wastewater Lagoon Eff lu ent (USA) Biological Rotating Disc Scale-up Design: Dissolved Oxygen Effects (USA) Nitrification in Free-Flowing Streams (USA) Ion Exchange in a Moving Bed of Magnetised Resin (Australia) Uptake of Americium-241 by Algae and Bacteria (USA) Efficiency of Attached Organisms in the Simulation of SelfPurification and Oxygenation Capacity of Flowing Waters (Germany) Recovery of zinc using Chelating Resin (Japan) Nutrient Exchange Kinetics in Water Sediment Interface (USA) Comparison of Semi-Continuous and Continuous Flow Bioassays (USA) Water Demineralisation by a Thermally Regenerable Ion Exchange (Australia) Mercury Transport Interacting with Bed Sediment Movements (Canada)

Conference Calendar IAWPR SYDNEY 1976

22

â&#x20AC;˘

INTERNATIONAL CONFERENCE

CONFERENCE CALENDER (continued)

JOURNAL SUBSCRIPTIONS CLEAN AIR & WATER EQUIPMENT EXHIBITION June 1 - 4 , 1976 UNITED STATES TRADE CENTER 37 Pitt Street , Sydney (11.00 a.m . to 6.00 p.m. daily)

AUSTRALIAN WATER & WASTEWATER ASSOCIATION JOURNAL I enclose herewith the sum of $ ...... . (Australian) as prepayment for supply of the following issues of 'WATER' March

ENVIRONMENT '76 OCTOBER 8-13, 1976 EXHIBITION BUILDING, MELBOURNE

o

June

o

Sept. o

Dec.

o 197-

Note:AII subscriptions conclude with the December issue, renewals are due by the end of February for a full year 's subscription . Price, including surface mail to all countries, is $1.00 (Aust .) each issue, made payable to the A.W.W.A. - 'WATER'.

Name .. ......... .... ......... .. ... .. .. .... ....... ... ... .. ........ .. ... ..... .

Officially launched , March 3rd by the Chairman , Mr. A. Dunbavin Butcher, Deputy Director Victorian Ministry for Conservation . Also announced were • an environmental project competition for Victorian school students, • the awarding of an outstanding environmental painting for a 'major contribution in environmental protection ', • a new emphasis on 'selling' environmental matters to the general public, • newspaper (Melbourne Age) support with production and T.V . and radio advertising of a special supplement, • a three day (Oct. 11 -13) Environment Conference.

Address ... .. .......... ..... .... .. .. .... .................. .... ............ .

Mail this form to:

A. H. Truman

A.W.W.A. MEMBERSHIP NEW ZEALAND - 1976 WATER CONFERENCE August 24-26/Field Trips 23rd For details write : Dr . H. Melcer , Massey Ufl iversity , Palmerston Nth ., N .Z.

Request for Application Porm for Membership of the Association To the Hon. Secretary, Australian Water & Wastewate( Assoc ., Mr. R. F. Goldfinch , P.O. Box 359, Canberra City, A.C .T., 2601

1, .... ....... ....... .... ........ ... ........ ,., ........... .... . , ........ ,, .. ,, .. .

(Name)

National Water Well Association of Australia 6th Annual Convention - October 17-20 Adelaide. Papers on the theme "GROUNDWATER EXPLORATION" Details from - P.O. Bo x 91, St. Ives , 2075 .

49th WPCF CONFERENCE October 3-8 Minneapolis, Minnesota , U.S.A. Papers are called for For Details - Peter A. Krenkel , C / o Tennessee Valley Authority , 268 401 Building, Chattanooga , Tenn . 37401.

of, ............ .................................. ............ ............ ... .. .

(Address) do hereby request an application form for membership in your Association.

Membership is in four categories .

1. Member - qualifications suitable for membership in the Inst. of Engineers. or other suitable professional bodies .

2. Associate - experience in the W.& W.W. Industry, without formal qualifications .

3. Student.

4. Sustaining Member - an organisat ion involved in the W.& W.W. Industry wishing to sustain the Associat ion.

23

TOC in water to a precision of + 50 parts per BILLION?

Yes. [And find it Fast] Within 5 minutes the well-accepted Dohrmann® TOC Analyzer determines organic carbon in water. Now , new features expand its capability, making it the most versatile and rapid carbon in water instrument available to municipal and industrial laboratories. The DC-50 series, based on proven , EPA-accepted* methodology, now offers: Low level analysis: Model DC-52S is ideally suited for determining TOC in surface or drinking water . Using the sparge method , it measures extremely low levels of organics in water to a precision of± 0.05 mg/ 1 (50 ppb) with 100% recovery. Analysis time: 5 minutes. Sample preparation time : 2 minutes .

High level analysis: Model DC-52D measures organics in water up to 6,000 mg/ 1 with a relative precision of ±3% . Even the most difficult samples - seawater sludges, sediment - pose no problem s. All important volatile organics are st:parated from residual organics.

Broad linear range , 5-minute analysis , and a choice of sample handling methods are exclusive features.

Whatever the application, whatever the budget, there's a DC-50 series analyzer for the job.

For free 12-page brochure, call (03) 95-1822.

THE OBJECTS OF THE A. W.A.A. THE OBJECTS AN D PURPOSES OF THE ASSOCIAT IO N AS STATED IN THE RULES ARE TO:(a) In vest igate and promote kn ow ledge of (i) W ater reso urces. contro l and ma nage ment. water qua lity standards a nd qual it y met hods of exa minati on . W ater collect ion . transmission. treatment a nd distrib ution. (ii) The mea ns a nd meth ods of effecting the operatio ns in (i}. (ii i) Th e nat ure, coll ect ion, trea t me nt. d isposa l a nd re-use of waste wa ters. (iv) The mea ns and methods of effecting the operations invol ved in (iii) . (v) The design, co nstruct ion . operatio n a nd manage ment of water and wastewater treaime nt works. (vi} The study, promotion a nd e ncouragement of pollution con trol of receivin g waters. (b) Protect a nd improve the e nvironm ent by a better understanding of th e principles of water qua lit y. treatment. water re-use. ecology and pollution controls. (c) Encourage research in the above fields. (d) Fac ilit ate the inte rcha nge of technica l knowledge in the above fields among its members a nd ot her interested persons and organisati ons by means of meetings a nd the pub licatio n of technical papers. (e) Estab lish co mmittees to exam ine a nd repo M upon specific subjects in t he above fi elds. (f) Affil ia te wit h a ny oth er inst itu te or assoc iati on whose objects are similar to those of th e Assoc iat ion. (g) Instru ct and t rain me mbers or ot her persons interested in the objects of t he Assoc iation.

MEMBERSHIP There shall be five grades of members termed respectively. Members, Associates. Students. Susta ining Me mbers and Hono rary Life Members.

MEMBERS sha ll comprise persons possessing qua li ficatio ns of recognised professiona l sta nda rd as Biologists. Chem ists, Eng ineers. Med ica l Practitione rs.

Microbiologists. Hydrologists or oth er allied professions, a nd actively engaged upon. or int erested in t he objects of t he Assoc iation.

PUMPING Viscous Materials Abrasive Slurries Corrosive Fluids Then pump with Flex-I-Liner - The Rotary Sealless Plastic Pump.

Capac ities 1/3 to 40 G.P.M . No contamination, operates dry , non-agitating flow.

FROM

ENVIROTECH

DOHRMANN R. & D. Instruments

Ply . Ltd., 2 Corr Street, Moorabbin, Vic . 3189

24

OF COURSE

THE ONLY NAME YOU NEED TO KNOW FOR CHEM ICAL PUMPS - METER ING AND TRANSFER .

ACROMET PTY. LTD. P.0. Box 491, Clayton, Victoria, 3168.

Telephone: 547-3077.

5/161-163 Sth. Creek Rd., Dee Why, NSW, 2099 .

Phone: 982-8055.

If clean water is an essential part of your process plant ... or the economic separation of suspended, entrained or dissolved materials such as chemicals, minerals, oils, spirits, etc . ... then you need the specialised skills and equipment available from Permutit.

De-ionisers/ Filters Reverse osmosis

~ ()

e a.

Permutit treats

:~.u0I ~ CCC ' C

el

$

Cl) II)

~¡en0

Cl)

a';~

a:

0

Nobody treats water more cleanly than Permutit!

IPERMUTITI T he Permutit Company of Au strali a Pty . Limited A Subsid iary of THE PERM UT IT COM PANY LTD . ENGLAND , A Member of the Portals Gro up Cnr. Watt le Road and Short Street, Brookvale, N .S.W. 2100 Telephone : 93-0311 . Tele x: AA24742 Cables: T hep ermutit, Sydney .

P.O. Box 117, Brookva le, N.S.W. Australia 2100.

44 Koorna ng R oad , Scoresby, V ictori a Austra l ia 3179 T elep hone: 763 -8988 Tel ex: AA3 1868 50 Leichhardt Street, Spring Hill , Queensland.

Austra lia 4000 Telephone : 229-5800 T elex : AA 41049

PTOOl P RM

•

1gre'1\T water A COMPLETE SERVICE

IN

e e e

SURVEYS AND CONSUL TING

e OVER 40 YEARS

PILOT STUDIES OF WASTEWATER

e

DESIGN AND MANUFACTURE

e

·

POLLUTION CONTROL

EXPERIENCE AND RELIABILITY INSTALLATION, TESTING AND COMMISSIONING CONTINUOUS AFTER-SALES SERVICE

Oil Separation and Removal The unit illustrated is the result of an approach by oil using ...,~·-':::.~:::J industries to Pettigrew .....,.....,:::.===: Engineering Research & Development Division to design and produce an oil separation unit operating without the use of chemicals or filters.

The effluent is required to meet the relevant water quality standards ..

PETTIGREW ENGINEERING CO PTY LTD 34 REGINALD STREET, ROCKLEA, OLD ., 4106, AUSTRALIA TELEPHONE (07) 275-3322 - CABLES "PECOTRADE" PRINT E D BY H E DGE S

a

B E LL PT Y. LT D., MARYBOROUGH VI CTORIA