/10_2005_Wastewater_treatment_

Wastewater Treatment in Filter Beds Evaluation of two onsite treatment plants

Daniel Hellstrรถm, AP Lena Jonsson, AP

R nr 10, juli 2005

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Wastewater Treatment in Filter Beds - Evaluation of two onsite treatment plants in Sweden

Daniel HellstrĂśm and Lena Jonsson Stockholm Water July 2005

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Wastewater Treatment in Filter Beds Evaluation of two onsite treatment plants

Daniel HellstrĂśm, AP Lena Jonsson, AP

juli 2005

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Preface The aim of the NI project no 02056 “Wastewater Treatment in Filter Beds 2002 – 2005” was to evaluate onsite sewage treatment systems in the Nordic countries. Magnhild Føllesdal, maxit Group, has been the project manager. This project was carried out with support and funding from the Nordic Innovation Centre (NICe). Nordic Innovation Centre is the Nordic Council of Ministers’ single most important instrument for promoting an innovative and knowledge-intensive Nordic business sector.

This report presents the results from the two plants installed in the district of Bornsjön, Sweden. The evaluation of the Swedish plants has been done by Dr. Daniel Hellström, Lena Jonsson and Lennart Qvarnström at Stockholm Water Co. All persons at Stockholm Water Co.`s accredited laboratory performing all the analyses are gratefully acknowledged. The authors would also like to thank the personal working with the protection of Lake Bornsjön. This project would not have been possible without their support.

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Summary Two wastewater treatment plants designed for 10 and 7 pe, respectively, were studied. The plants consist of a septic tank, two parallel connected trickling filters filled with Filtralite 2 4, and a large filter bed filled with Filtralite P. The biological processes developed gradually and after 9 months of operation the nitrogen removal was 50 % - 80 % and the removal of organic matter exceeded 90 %. The nitrification was incomplete in both plants and about 20 % of the influent nitrogen was emitted as ammonium. The treatment plant with highest nitrogen load had the highest degree of nitrification during stable operation conditions. This indicates that local conditions, such as wastewater composition and/or small differences in operational conditions, are important.

The reduction of phosphorus has during the two first years of operation exceeded 99 % and the effluent concentrations have generally been below 0.05 mg P/l. The concentrations of phosphate in the effluent have been below 0.01 mg PO4-P/l during nearly the whole period of study. However, there are indications that one of the filter beds is partially saturated and effluent concentrations might increase in the near future. No E. coli nor Fecal Enterococci have been found in the effluents from the plants.

Economically, the treatment plants are characterised by relative high investment costs but relatively low operation costs. The installation and construction of the plant is rather complicated and requires special competence.

The treatment plants had good removal efficiencies compared to other alternatives. However, it is also important to consider the environmental impact from production, transport and handling of Filtralite P. Thus, a thorough LCA is recommended.

The plant should be regularly controlled to assure that there is no clogging of the spraying nozzle or any other blockages in the system. Thus, inspection pipes should be available at all critical positions. Otherwise, the treatment plants are uncomplicated and the processes require a minimum of operational control and maintenance.

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Sammanfattning Två avloppsanläggningar dimensionerade för 10 respektive 7 personekvivalenter studerades.

Anläggningarna består av en slamavskiljare, två parallella biobäddar fyllda med Filtralite 2 - 4 och en stor markbädd fylld med 70 m3 respektive 50 m3 Filtralite P. Efter 9 - 10 månaders drift var biofilmen på keramikgranulerna, Ø 2 - 4 mm, i biobäddarna fullt utvecklad och reduktionen av organiskt material låg vanligtvis över 90 % och kvävereduktionen låg mellan 50 % och 80 %. Nitrifikationen var ofullständig vid båda anläggningarna och i genomsnitt släpptes ungefär 20 % av inkommande kväve ut som ammonium. Noterbart är att den anläggning som hade högst kvävebelastning hade högst nitrifikationsgrad då processen inte stördes av partiell dämning av biofiltret. Detta indikerar betydelsen av lokala avvikelser mellan två, i övrigt lika, biobäddar. Förklaringen i detta fall kan eventuellt härledas till skillnader i avloppsvattnets sammansättning och/eller driftsförhållanden.

Fosforreduktionen har under de två första årens drift legat över 99 % och utgående halter har legat under 0,05 mg P/l. Koncentrationen av fosfatfosfor i utloppet har legat under eller nära 0,01 mg PO4-P/l nästan hela tiden. Det finns emellertid indikationer på fosformättnad i en av bäddarna och utgående halter kan komma att öka relativt snart. Ingen förekomst av E. Coli eller Fekala Enterococcer har kunnat påvisas i utgående vatten från anläggningarna.

Anläggningarna uppvisade således goda reningsresultat. Vid en samlad miljöbedömning bör dock även hänsyn tas till miljöpåverkan i samband med bland annat produktion och hantering av filterbäddsmaterialet. Detta har emellertid inte ingått i projektet.

Anläggningskostnaderna var relativt höga, medan driftskostnaderna är betydligt lägre än för exempelvis minireningsverk. Installationen av de olika komponenterna och anläggandet av markbäddarna var relativt arbetskrävande och krävde tillgång till specialiserad entreprenör samt arbetsledning med specialkompetens. En annan design, med kompaktare bäddar där filtermaterialet byts oftare, skulle kunna innebära enklare installation och en lägre totalkostnad.

Ur driftssynpunkt är anläggningarna enkla att sköta. De kräver dock regelbunden tillsyn, bland annat kontroll av spridardysornas funktion i biobäddarna samt att det inte finns fördämningar/igensättningar i systemet.

En viktig aspekt, som delvis belysts i det finska delprojektet (ej redovisat i denna rapport), är användningen av mättat filtermaterial på jordbruksmark. De studier som gjorts visar att mättat filtermaterial kan fungera som fosforgödsel, men det krävs utveckling av system för en fungerande praktisk hantering.

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6 Contents PREFACE.............................................................................................................................................................. 3 SUMMARY ........................................................................................................................................................... 4 SAMMANFATTNING ......................................................................................................................................... 5 1

INTRODUCTION ....................................................................................................................................... 7 1.1 1.2

PROJECT DESCRIPTION .......................................................................................................................... 7 REGULATIONS IN SWEDEN .................................................................................................................... 8

2

DESIGN AND SITE CONDITIONS ....................................................................................................... 10

3

BUILDING EXPERIENCE...................................................................................................................... 13

4

OPERATION EXPERIENCE / OPERATION DATA .......................................................................... 14

5

SAMPLING AND ANALYSES................................................................................................................ 16

6

RESULTS AND DISCUSSION ................................................................................................................ 18 6.1 6.2 6.3 6.4 6.4.1 6.5 6.5.1 6.6 6.6.1 6.7 6.8 6.9

SUMMARY – REMOVAL OF N, P AND ORGANIC MATTER ...................................................................... 18 LOAD – FLOW, N, P, AND ORGANIC MATTER ....................................................................................... 22 TEMPERATURE .................................................................................................................................... 26 PHOSPHORUS ...................................................................................................................................... 27 Phosphorus profiles in the filter beds............................................................................................ 29 NITROGEN........................................................................................................................................... 31 Nitrification ................................................................................................................................... 34 ORGANIC MATTER .............................................................................................................................. 38 Degradation of organic matter in the trickling filter .................................................................... 42 BACTERIA ........................................................................................................................................... 46 ALKALINITY, CA, AND PH................................................................................................................... 48 COMPARISON OF GRAB SAMPLE AND COMPOSITE SAMPLE .................................................................. 49

7

DISCUSSION............................................................................................................................................. 50

8

CONCLUSION .......................................................................................................................................... 52

9

REFERENCES .......................................................................................................................................... 52

APPENDIX 1: CONCENTRATIONS OF N, P, ORGANIC MATTER AND FLOW.................................. 53 APPENDIX 2: FÅGELSTA (N, P, ORGANIC MATTER)............................................................................. 54 APPENDIX 3: TALBY (N, P, ORGANIC MATTER) .................................................................................... 59 APPENDIX 4: ANALYSES FROM SAMPLING IN FILTER BEDS ........................................................... 64 APPENDIX 5: ANALYSES DATA SHEET - FÅGELSTA ............................................................................ 66 APPENDIX 6: ANALYSES DATA SHEET - TALBY .................................................................................... 72

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1 Introduction 1.1 Project description A Nordic project with large filter beds in onsite wastewater plants started in October 2002.

The project is part of the NI project no 02056 Wastewater Treatment in Filter Beds 2002 2005. The company maxit Group is leading the project, which was financially supported by Nordic Innovation Centre. Two plants with filter beds filled with Filtralite were built during November and December 2002 in the catchment area of Lake Bornsjön, the reserve water supply for the residents of Stockholm, see figure 1. The installation of the treatment plants is a part of Stockholm Water´s strategy to reduce the phosphorus load on Lake Bornsjön. The purpose of the project was to evaluate the function of large filter beds in four Nordic countries, Norway, Denmark, Finland, and Sweden during two years, and to detect the long term effects of phosphorus treatment in these beds.

Figure 1. Map over Stockholm and Lake Bornsjön marked with a darker blue colour.

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Figure 2. Map over the Lake BornsjĂśn and its catchment area. The location of the treatment plants are indicated by the red circles.

1.2

Regulations in Sweden

On the national level, there is a general demand that wastewater should be managed in order to minimise hygienic risks and to avoid negative environmental impact. The use of nonrenewable resources shall be as low as possible and valuable resources (such as phosphorus) shall be recovered. Earlier, the regulation concerning small onsite treatment systems was mainly focused on health aspects and it was required that septic tank effluent should be treated before discharge to the recipient. The interpretation of this regulation was given by Swedish Environmental Protection Agency (SEPA) who suggested an infiltration bed or a filter bed after the septic tank (SEPA, 1987). Today, there is no official guideline available for small onsite wastewater treatment plants from SEPA. However, new regulations, with demands for nutrient removal etc. are expected in December 2005.

The regulation concerning use of phosphorus saturated filter material is indistinct. There is however no indication today that use of filter material in agriculture will be prohibited as long as the quality requirements for sewage sludge are fulfilled.

The local environmental authorities (one in each municipality) in Sweden are both responsible for the supervision and for giving permissions for installations of small wastewater treatment plants. Permission to install, utilize, take samples from, and evaluate the wastewater treatment C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

9 plants was applied for at the local environmental department in the municipality of Salem where the plants are situated. The permission was granted without any problems.

In this project, we were aiming at the requirements from another project in Sweden, “Bra Små Avlopp”, that consisted of plants in the size of 5 pe (Hellström et al., 2003). The required degree of removal of phosphorus, nitrogen, and BOD7 in that project is given in Table 1, and it was used in this project as a goal.

Table 1. The goals for the removal efficiency in the project “Bra Små Avlopp”.

Phosphorus Total nitrogen Ammonia nitrogen BOD7

Minimum removal efficiency > 70 % > 70 %

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Desirable removal efficiency > 90 % > 50 % > 90 % > 90 %

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2 Design and site conditions Septic tank

Pump well

Prefilter

Inlet

Filterbed

Water level control Outlet

= sample point

Figure 3. Drawing over the plants in Sweden.

Two plants, connected to this filter bed project, were built in Sweden during November and December 2002 in Talby, called Nedergården on the map in Figure 2 above, and in Fågelsta.

A drawing presenting the plants is shown in Figure 3. In Fågelsta, two houses, each occupied by one family, with two adults and one child, were connected to the plant. In Talby, the Stockholm Water Co. has an office, where 5 - 6 adults are working. Above the office, there is also a small apartment for students doing there practical training periods at Stockholm Vatten.

The students normally stay there for half a year. Smaller or larger groups are often visiting the office.

Table 2. Data for the treatment plants at Bornsjön.

Location Design criteria Persons connected Load

Septic tank Pump well Trickling filter (pre-filter) Filter bed

Talby Fågelsta 10 pe 7 pe 5 – 6 working person, visitors, 4 adults 1 student1 2 children 31 g N/d 16 g N/d 4.1 g P/d 2.5 g P/d 72 g TOC/d 17 g TOC/d 256 g COD/d 58 g COD/d 0.54 m3/d 0.41 m3/d 3 6 m , Ifö Trapper 6000 Ø 1.1, operated by level control 2 modified Ifö Trapper 4000 each containing 2.3 m3 Filtralite 2 – 4 and an area of 3.5 m2.

50 m3 Filtralite P 0-4 mm Length = 11 m Width = 4.5 m Depth = 1.0 m

70 m3 Filtralite P 0-4 mm Length = 9.3 m Width = 7.5 m Depth = 1.0 m

In both plants, a new horizontally placed septic tank of 6 m3, Trapper 6000, consisting of three chambers, was installed. After that the wastewater is led to a sampling well with a 1

One student lived in Talby between 2003-08-01 and 2004-02-27 and another student lived there between 200408-02 and 2005-02-07.

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11 diameter of 400 mm and then pumped to the pump well. After the pump well in Fågelsta, a storage tank was installed to have a buffer capacity if the pump should fail. However, due to leakage the storage tank was only in operation until April 2004. From the pump well the water is pumped to two trickling filters (In the diagrams, the samples taken after these filters are referred to as “bf” = before large filter bed or “TF eff” = trickling filter effluent.) The trickling filters are made of rebuilt septic tanks of 4 m3 from Ifö EcoTrap, Ifö Trapper 4000, and contains 2,3 m3 of Filtralite 2 – 4 (small, ceramic spheres), and have a outer diameter of Ø 2.2 metres and an inner diameter of Ø 2.1 metres as an average. The wastewater is spread over the spheres with two nozzles in each of the two tanks, and a biofilm was growing in time on the surface of the spheres. At the bottom of the trickling filter, the outlet is collected by a horizontally placed drainage pipe (Ø 110 mm) sliced with notches of ≤ 2 mm.

After the trickling filters, another sample well (Ø 110 mm) is located. The wastewater is then led to a large filter bed with a horizontal flow. The filter mainly consists of Filtralite P, i.e. crushed spheres made from a ceramic material that also contains Calcium ions, Ca2+, that should be able to precipitate enough phosphate phosphorus for 15 years. Plastic white tarpaulins are placed below and above the filter bed in order to keep the wastewater in the bed and to avoid drainage water entering the filter bed. The horizontal inlet pipe and the outlet pipe were covered by Filtralite, 4 - 10 mm (about of 0.5 m3 per metre of pipe). In Talby, the lengths of the pipes were about 4 m each and in Fågelsta they were about 6.5 m long. All pipes had a diameter of 110 mm. These pipes are perforated and functioning as nozzles for influent and effluent wastewater, respectively. Each end of the pipes continues with a vertically placed inspection pipe.

A drawing over the filter bed is shown in Figure 4.

Figure 4. Drawing over the construction of the filter bed.

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12 The large filter beds were built by “Styrhytten AB” according to the following from the top and downward in the bed: • grass • soil approximately 0.3 m • tarpaulin, impermeable to water, white • geotechnical sheet, glass fibre reinforced sheet, 0.125 kg/m2, grey • Filtralite Ø 8 - 14 mm, 0.1 m • Filtralite P, approximately 1.0 m • geotechnical sheet, glass fibre reinforced sheet, 0.125 kg/m2, grey • membrane, rubber like, impermeable to water, black • geotechnical sheet, glass fibre reinforced sheet, 0.125 kg/m2, grey • sand for drainage Ø 0 - 8 mm, 0.1 - 0.2 m • Two pipes for drainage, Ø 110 mm, at each side but outside the filter bed parallel to the direction of the flow of the wastewater at a level just below the bottom of the filter bed, black. The drainage pipes were provided with inspection and sample wells in order to inspect that the tarpaulin really is impermeable to water.

In each plant 18 vertically situated pipes were placed in the filter bed, which makes it possible to take samples of wastewater and Filtralite P in the filter bed. Six pipes have their lowest point 0.1 metre over the bottom of the filter bed, six pipes go down to 0.5 metre over the bottom, and six pipes not filled with Filtralite P go down to the bottom of the filter bed.

Finally, in the Talby plant, a vertically placed pipe is collecting effluent wastewater with another automatic sampler receiving a signal from the flow meter before the water leaves the plant and flows to a ditch. The level of wastewater, that is the edge of the weir in the effluent pipe, is 0.19 metre below the highest point of the plastic tarpaulin. In both plants, grab samples were also taken in this effluent pipe.

The condition of the water in the well connected to the households that are feeding the treatment plants with wastewater can affect the function of the plants. Grab samples have been taken in the households (Table 3). In the Talby plant the alkalinity is relatively high.

Both plants have relatively high hardness of the water.

Table 3. Analyses of water from the wells connected to the households within the project.

Sample place Talby Well dug/ drilled dug Distance to the well, m 200 samle point: kitchen Sample day 2002-11-19 2003-01-16 2003-01-16 Samle taken after minutes 10 0 10 pH 7.93 7.73 7.68 Temperature, degees C 16.1 10.8 10.8 Turbidity, FNU 0.86 7.8 7.8 Conductivity, mS/m 35.5 33.9 33.9 Hardness, dH/Ca i mg/l 8.4 7.9/56.1 7.7/54.9 168 159.2 157.1 Alkalinity, mg HCO3/l Colour, mg Pt/l 5 20 21 TOC, mg/l 1.3 1.4 1.4 TS, mg/l 220 219 216 Iron, µg Fe/l 95 510 1400 Copper, µg Cu/l <20 44 22 Manganese, µg Mn/l <20 25 180 Calcium, mg Ca/l 43 42 42 Magnesium, mg Mg/l 11 8 8.8

Fågelsta dug 100 sample point: kitchen 2003-01-16 2002-11-19 2003-01-21 2003-01-21 warm w. 2 10 0 10 7.74 6.71 6.67 6.67 14.6 16.1 10.1 12.3 1.12 0.24 0.068 0.067 33.1 41.1 40.4 40.7 7.6/54.4 8.3 8.6/61.3 8.6/61.3 153.7 102 102 102 6 <5 <5 <5 1.3 1.6 1.8 211 266 257 258 100 78 80 130 86 67 54 31 <20 <20 <20 <20 42 41 43 43 9.4 11 10 11

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2003-01-21 warm w. 2 6.80 10.8 0.58 40.9 8.6/61.1 102 5 2.0 258 52 96 <20 44 11

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3 Building experience No greater difficulties arised during the time of building of the two plants. It was necessary to be thorough and follow the drawings with great accuracy. It was also urgent to be careful not to puncture the tarpaulins during the digging. It is important to have a drainage system below the large filter bed, otherwise displacement forces might lift the bed.

The extent of the work with excavation is totally dependent of the local conditions. At both Talby and FĂĽgelsta, the demand was relatively extensive regarding the excavation. In Talby, there was a rock where the septic tank was planned to be situated. The location of the septic tank was therefore moved a small distance, which resulted in a rather extensive work of digging and the moving of lots of excavated material. At FĂĽgelsta, the plant was placed at the same place as the old plant had been situated. When the old plant (consisting of a septic tank, pump well, and a filter bed of 40 m2) was disconnected, it was revealed that most of the wastewater bypassed the old filter bed by an overflow in the old pump well. This is not an uncommon experience and it shows that a thorough control of the function after start of a new plant is very important. At the work of digging, forgotten pipes, tanks, and cables belonging to the old plant were discovered. The experiences from other works show that this is not uncommon and results in a more extensive work. Installation of the trickling filter and the filter bed did not result in any other problems than that a great accuracy had to bee observed.

In summary, the excavation and transport of excavated material became rather extensive due to the local conditions. Everything functioned technically well but the demand for accuracy in the performance of all the work with excavation is great. All bottoms of hollows should be compacted with a vibrator. The filter material is delivered in large sacks, which was a simple and well functioning system to handle relatively large volumes of material.

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4 Operation experience / operation data The plants were taken into operation 2002-12-18 when the first influent entered the plants.

The Talby plant was filled with wastewater in March 2003, and the first samples were taken in the two plants 2003-05-07. After 9 - 10 moths, the biofilm on the small ceramic spherical granules in the trickling filters were fully developed and both the reduction of organic matter and total nitrogen functioned satisfactory (see chapter “6. Results”).

In the very beginning, problems were discovered with an uneven flow pattern from the nozzles in the trickling filters. Black plastic cuttings remaining from the period of building were found in the nozzles (this occurred a number of times during the first time of operation and later on it ceased to appear). When these were removed, a better distribution over the filter was achieved. Once or twice a year, the nozzles and the spraying pipes in the trickling filter should be rinsed from deposits.

In the middle of March 2004 in the Fågelsta plant, an inflow of drainage water into the storage tank situated after the pump was discovered. The leakage was so large that the water was flowing upstream to the sampling well and high flows were detected2. The storage tank was taken out of operation 2004-04-16 and the leakage stopped. During the time of the leakage, the concentration of suspended solids in the sample point between the trickling filter and filter bed was very high. This might be a result of biofilm having been flushed off the granules in the trickling filter or it could also be some of the material of the granules been flushed out. The last explanation is less probable.

In the autumn 2004, it was discovered that there was a low concentration of nitrate and nitrite nitrogen leaving the trickling filter in Fågelsta. However, there was a reduction of total nitrogen indicating a denitrification process in the trickling filter. An investigation 2004-1116 revealed that the lower part (0.2 m) of the trickling filter was submerged. The pipes between the trickling filter and the filter bed were inspected. They were full with water, sludge, and earth. There was still an inclination between the sample point and the filter bed but not between the trickling filters and the sample point, revealing that the trickling filters had settled. These pipes, including the pipes dividing the water over the filter bed, were rearranged and flushed 2005-01-26, and the trickling filters were lifted. All pipes before the septic tank were inspected, re-arranged, and flushed in the beginning of February 2005.

During the end of March 2005, the snow melted in the Stockholm area and the flow in Fågelsta increased from normally 3 m3 to 5 m3 per two weeks. In beginning of May 2005, after a period with rain, the flow was 6 m3 per two weeks. This shows that there was still a leakage somewhere but a much smaller leakage than before in the system.

In the Talby plant, a toilet was leaking in the house. This was discovered 2004-04-06 and immediately taken care of. A water heater was leaking from a safety valve probably from the end of January 2004 or from the beginning of the experiments. The valve of the water heater was repaired 2004-06-17. These two leakages increased the flow from around 400 l/d to nearly 1000 l/d.

2

The diagrams of concentrations showing the function of the Fågelsta plant can therefore be somewhat misleading.

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15 After the flow had been reduced it was observed in June 2004 that the water level did not reach the edge of the weir in the outlet. Even if no water could be observed in the drainage pipe, the conclusion is that water leaked out from the filter bed.

The sludge was removed from the septic tank in FĂĽgelsta 2003-12-05 and 2004-05-28, and in Talby 2004-04-14. The next collection of sludge is planned to take place in the end of June, 2005.

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5 Sampling and analyses The wastewater was taken for analyses in both plants by flow controlled automatic sampler placed after the septic tank, after the trickling filters, and also after the filter bed in the Talby plant (see Figure 3). In both plants, grab samples were taken after the filter bed.

The frequency of the automatic sampling was regulated by the inflow to the sampling well after the septic tank. When the water level reached the upper level meter, the water is pumped down to the lower level meter. At the same time the water was measured with a flow meter, Danfoss Magflo FLowmeter Type MAG 5000, and a signal was sent to the three automatic samplers in the plant, where samples then were taken. One sample was taken for approximately every 5.7 litres of water. The samples were collected in seven 5 litres plastic bottles, each bottle containing 2 days of water samples, placed in a refrigerator3. All but the last bottle to be filled contained 25 ml of 4 M sulphuric acid to conserve the sample. The composite samples of 14 days, of 12 days, of 2 days, and the grab samples were all analysed in Stockholm Water Co.`s accredited laboratory. For economic reasons, the frequency of some analyses was decreased in December of 2003. Different analyses were therefore made during different periods of time and at different sample points in the plants, see Appendix 5 and Appendix 6. The methods of analyses are presented in Table 4. The analyses were performed with method and the uncertainty (with 95 % accuracy of measurement) mentioned in Table 4. In Table 4 the larger uncertainty refers to the lowest part of the measuring range.

3

In Talby, the refrigerator containing influent samples failed to operate. This resulted in warm samples at several occasions. The total amount of nitrogen and phosphorus should not be affected by this, but there is a risk that organic compounds in bottles without sulphuric acid was degraded (e.g. BOD7 concentrations in the influent might be underestimated).

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Table 4. Method of analysis and uncertainty for different parameters.

Parameter

Method of analysis

SS, Suspended Solids VSS, Volatile suspended solids COD, Chemical oxygen demand BOD7, Biochemical oxygen demand during 7 days TOC, Total organic carbon Tot-P, Phosphorus

SS 028112 – 3 SS - EN ISO 872 – 1 SS 028142 - 2 mod

Tot-P, Phosphorus

SS 028143 - 2 and SS EN 25814 – 1 SS - EN 1484 – 1 SS 028127 – 2 if concentration < 1 mg/l ASN 5240 - SE * if concentration ≥ 1 mg/l SS 028126 – 2 AN 300/ASN 3503 *

Uncertainty, % k=2 50 – 22 50 – 22 26 – 12 24 – 10 15 – 9 34 – 11 22 – 12

PO4-P, Phosphate phosphorus Kj-N, Organic nitrogen and ammonium nitrogen NH4-N, ammonium nitrogen AN 300 * (NO3+NO2)-N, Nitrate nitrogen AN 5201 * and nitrite nitrogen

34 – 11 50 – 10

HCO3-, Alkalinity Ca, Calcium Mg, Magnesium Fe, Iron

18 – 13 10 8 33 – 11

SS - EN ISO 9963 - 2 SS - EN ISO 11885 - 1 SS - EN ISO 11885 - 1 SS 028150 - 2 and SS - EN ISO 11885 - 1 Al, Aluminium SS 028150 - 2 and SS - EN ISO 11885 - 1 pH pH meter WTW340 with the probe SenTix21 Conductivity SS - EN 27888 - 1 E. coli Colilert®-18/MPN method Fecal enterococci EnterolertTM * Application note according to Foss/Tecator, ** not applicable

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46 – 10 18 – 10

16 – 10

26 – 4 ** **

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6 Results and discussion 6.1

Summary – removal of N, P and organic matter

The reductions of total phosphorus, total nitrogen, TOC, COD, and BOD7 in the plants are presented in Figure 5 - Figure 8. In both plants, the biofilm was not fully developed until after 9 - 10 months of operation and the degradation of organic matter and the nitrification improved continuously during this period. Thus, the results are presented both as median and average values after 9 months of operation and for the whole period of evaluation (i.e. May 2003 – May 2005), see Table 5 and Table 6. For both plants, the reduction of phosphorus was above 99 % and the reduction of organic matter was above 90 % for almost all parameters after 9 months. In Fågelsta, the nitrogen removal was about 70 %. In Talby, the fluctuation in nitrogen load and concentrations might have affected the evaluation of nitrogen removal rates and there is a relatively large discrepancy between average and median values (see also “6.5 Nitrogen”). However, the average nitrogen removal in Talby was 50 %.

Table 5. Reduction of total phosphorus, total nitrogen, TOC, COD, and BOD7 in % as median and average values in the plant in Fågelsta. The first column presents values after that biological removal processes were developed and the second column presents values for the whole period of sampling.

Substance Total P Total N TOC COD BOD7

Fågelsta, After 9 months of operation median / average, % 99.7 / 99.1 75.0 / 70.8 93.6 / 93.4 93.7 / 93.7 95.8 / 95.1

Fågelsta, May 2003 – May 2005 median / average, % 99.8 / 99.2 72.3 / 66.2 93.4 / 91.1 92.8 / 89.1 90.4 / 82.1

Table 6. Reduction of total phosphorus, total nitrogen, TOC, COD, and BOD7 in % as median and average values in the plant in Talby. The first column presents values after that biological removal processes were developed and the second column presents values for the whole period of sampling.

Substance Total P Total N TOC COD BOD7

Talby, after 9 months of operation median / average, % 99.8 / 99.7 61.3 / 50.0 92.9 / 91.5 88.6 / 88.9 94.0 / 91.5

Talby, May 2003 – May 2005 median / average, % 99.7 / 99.6 55.4 / 43.3 91.3 / 86.9 86.7 / 72.7 83.3 / 37.1

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19 100

reduction, %

80

Nred Nred* Pred Pred*

60

40

20

0 May03

Jul03

Sep- Nov03 03

Jan04

Mar- May04 04

Jul04

Sep- Nov04 04

Jan- Mar- May05 05 05

Figure 5. Reduction of nitrogen and phosphorus in the plant in FĂĽgelsta (* = 12-days composite samples have been used in the calculations, otherwise 14 d composite samples).

100

reduction, %

80

Nred Nred* Pred Pred*

60

40

20

0 May03

Jul03

Sep03

Nov03

Jan04

Mar- May04 04

Jul04

Sep04

Nov04

Jan05

Mar- May05 05

Figure 6. Reduction of nitrogen and phosphorus in the plant in Talby (* = 12-days composite samples have been used in the calculations, otherwise 14 d composite samples).

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20 100

reduction, %

80 BOD7red CODred CODred* TOCred TOCred*

60

40

20

0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 7. Reduction of organic matter in the plant in FĂĽgelsta (* = 12-days composite samples have been used in the calculations, otherwise 14 d composite samples).

100

reduction, %

80 BOD7red CODred CODred* TOCred TOCred*

60

40

20

0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 8. Reduction of organic matter in the plant in Talby (* = 12-days composite samples have been used in the calculations, otherwise 14 d composite samples).

In Table 7 and Table 8, the concentrations after 9 months of operation are presented as median, average, 5 % percentile, and 95 % percentile values. Median, 5 % percentile, and 95 % percentile values are chosen to avoid obvious outliers to affect the results too much.

Similar tables for the whole period are presented in Appendix 1.

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21

Table 7. Concentrations of substances after 9 months of operation in the Fågelsta plant, as median, average, 5 % percentile, and 95 % percentile values.

Fågelsta plant Substance Flow, l/d Total P, mg/l PO4-P, mg/l Total N, mg/l (NO3+NO2)-N, mg/l NH4-N, mg/l TOC, mg/l COD, mg/l BOD7, mg/l

After septic tank Median/average, 5 % p. - 95 % p.

498 / 554 253 – 1135 9.3 / 9.3 5.3 – 13 8.1 / 7.8 4.1 – 12 66 / 63 35 – 83 0.1 / 0.1 0.1 - 0.1 56 / 53 29 – 72 155 / 146 84 – 190 510 / 512 400 – 612 250 / 244 181 - 283

After trickling filter Median/average, 5 % p. – 95 % p.

Effluent Median/average, 5 % p. - 95 % p.

8.0 / 7.8 2.5 – 12 7.0 / 6.3 2.2 - 9.2 43 / 42 26 – 62 18 / 19 0.9 – 52 13 / 16 4.3 – 35 41 / 50 19 – 91 100 / 126 78 – 218 37 / 36 11 – 71

0.02 / 0.06 0.01 - 0.20 0.01 / 0.03 0.01 - 0.11 17 / 16 8.5 - 20 3.0 / 3.5 1.4 - 6.4 12 / 12 5.5 - 16 8.5 / 9.0 5.5 - 13 32 / 32 22 - 39 11 / 11 5 - 21

Table 8. Concentrations of substances after 9 months of operation in the Talby plant, as median, average, 5 % percentile, and 95 % percentile values.

Talby plant Substance Flow, l/d Total P, mg/l PO4-P, mg/l Total N, mg/l (NO3+NO2)-N, mg/l NH4-N, mg/l TOC, mg/l COD, mg/l BOD7, mg/l

After septic tank Median/average, 5 % p. - 95 % p.

322 / 408 104 - 888 7.5 / 8.7 2.2 - 18 5.9 / 7.3 2.0 - 16 57 / 59 13 – 114 0.1 / 0.1 0.1 - 0.1 50 / 53 10 – 102 70 / 65 19 – 120 230 / 256 164 - 402 67 / 74 41 – 113

After trickling filter Median/average, 5 % p. - 95 % p.

Effluent Median/average, 5 % p. - 95 % p.

5.7 / 7.3 2.5 – 16 5.8 / 7.1 2.5 – 17 49 / 52 17 – 95 34 / 33 13 – 48 12 / 18 0.7 – 49 19 / 20 7.5 – 41 59 / 75 44 – 136 11 / 10 4 – 17

0.02 / 0.02 0.01 - 0.03 0.01 / 0.01 0.01 - 0.01 18 / 22 11 - 46 9.3 / 7.7 0.3 - 13 13 / 14 2.2 - 35 4.4 / 4.3 2.5 - 6.6 25 / 26 15 - 38 5/6 2 - 12

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22

6.2

Load – flow, N, P, and organic matter

The flow to the plants has varied greatly mainly as a result of the problems with leakage into the plants (Figure 9 and Figure 10). The median flow to the plant in Fågelsta was 468 l/d and 370 l/d to the plant in Talby. The flow to the Fågelsta and Talby plant were about 360 l/d and 140 l/d, respectively, when no melting snow or rain leaked into the plant as drainage water.

2500

weekly average flow, l/d

2000

1500

1000

500

0 May03

Jul03

Sep03

Nov03

Jan04

Mar04

May04

Jul04

Sep04

Nov04

Jan05

Mar05

May05

May04

Jul04

Sep04

Nov04

Jan05

Mar05

May05

Figure 9. Flow in l/d to the plant in Fågelsta.

1200

weekly average flow, l/d

1000 800 600 400 200 0 May03

Jul03

Sep03

Nov03

Jan04

Mar04

Figure 10. Flow in l/d to the plant in Talby.

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23

The accumulated flow to the plants was studied. From the start of the plants 2002-12-18 to 2005-06-14 when the last samples were taken 493 m3 of wastewater has passed the flow meter in Fågelsta and 333 m3 has passed the flow meter in Talby. When there was a leakage from the storage tank in Fågelsta, an unknown amount of leakage water flow directly to the trickling filter. The reparation of the safety valve 2004-06-17 in the house in Talby is obvious in Figure 11.

600

Accumulated flow, m3

500

400 Fågelsta Talby

300

200

100

0 Dec02

Mar03

Jun03

Sep03

Dec03

Mar04

Jun04

Sep04

Dec04

Mar05

Figure 11. Accumulated flow to the wastewater treatment plants.

The phosphorus load, as a median value, on the Fågelsta plant was 4.1 g P/d, and on Talby 2.5 g P/d. The median load of nitrogen on Fågelsta 31 g N/d and on Talby 16 g N/d. And, finally, the median load of organic matter on Fågelsta was 72 g TOC/d, 256 g COD/d, and 115 g BOD7/d, and on Talby 17 g TOC/d, 58 g COD/d, and 13 g BOD7/d4. The loads are presented in Figure 12 - Figure 15. As mentioned, a student lived in Talby between 2003-08-01 and 2004-02-27 and another student lived there between 2004-08-02 and 2005-02-07. They have greatly affected the loads to the Talby plant.

4

The low BOD/COD-ratio in Talby might be explained that BOD load was calculated from 2 day composite samples while COD load was calculated from fortnight composite samples. It is also possible that the problem with the refrigerator in Talby affected the BOD values.

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70 60

load, g/d

50 Tot-Nin Tot-Nin* Tot-Pin Tot-Pin*

40 30 20 10 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 12. Nitrogen and phosphorus load in g/d to the plant in FĂĽgelsta (* = 12-days composite samples have been used in the calculations, otherwise 14 d composite samples).

35 30

load, g/d

25 Tot-Nin Tot-Nin* Tot-Pin Tot-Pin*

20 15 10 5 0 May03

Jul03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 13. Nitrogen and phosphorus load in g/d to the plant in Talby (* = 12-days composite samples have been used in the calculations, otherwise 14 d composite samples).

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25

400 350 300 BOD7in, d CODin CODin, d TOCin TOCin, d

load, g/d

250 200 150 100 50 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 14. Organic load in g/d to the plant in Fågelsta.

120 100

load, g/d

80

BOD7in, d CODin CODin, d TOCin TOCin, d

60 40 20 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 15. Organic load in g/d to the plant in Talby.

The accumulated load of phosphorus to the plants was investigated (Figure 16). In Talby, a somewhat larger slope may be seen during the autumns when the students lived in Talby. In Fågelsta, there is an obvious change in the slope in March 2004. During that month, the storage tank leaking into the plant was taken out of operation, and the potential backflow that might have caused an overestimation of the actual flow was hindered. The accumulated phosphorus from the start of the plants in 2002-12-18 to 2005-05-24 has been calculated to 4.2 kg total P in Fågelsta and 2.1 kg total P in Talby. With a density of 450 kg/m3 for Filtralite P, the material in the large filter bed, and a volume of 70 m3 and 50 m3 in Fågelsta and Talby,

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26 respectively, the binding of phosphorus could be calculated to 130 mg P bound/kg bed material in Fågelsta and 90 mg P bound/kg bed material in Talby.

4.5

Accumulated load of total P, kg

4.0 3.5 3.0 2.5

Fågelsta Talby

2.0 1.5 1.0 0.5 0.0 Dec02

Mar03

Jun03

Sep03

Dec03

Mar04

Jun04

Sep04

Dec04

Mar05

Figure 16. Accumulated load of phosphorus in kg to the wastewater treatment plants.

6.3 Temperature The temperature was measured in the sample point after the septic tank. During the period from 2004-05-04 to 2004-07-13 the temperature was measured in the sample point in the effluent from the filter bed. This change in measuring point is only obvious in Fågelsta. The thermometer in Fågelsta brook down in the beginning of October 2004 and a new probe was bought. The temperature has varied between 5 °C and 19 °C in Fågelsta and between 9 °C and 22 °C in Talby.

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27 25

Degree of C

20

15 Fågelsta Talby 10

5

0 May-03

Aug-03

Nov-03

Feb-04

May-04

Aug-04

Nov-04

Feb-05

May-05

Figure 17. The water temperature in the plants.

6.4 Phosphorus The median concentrations of total phosphorus after the septic tank, after the trickling filter, and in the effluent were 9.3 mg P/l, 8.2 mg P/l, and 0.02 mg P/l in Fågelsta and 6.3 mg P/l, 5.0 mg P/l, and 0.02 mg P/l in Talby. In the same sample points the median concentrations of phosphate phosphorus were 8.0 mg PO4-P/l, 7.1 mg PO4-P/l, and 0.01 mg PO4-P/l in Fågelsta and 4.5 mg PO4-P/l, 4.8 mg PO4-P/l, and 0.01 mg PO4-P/l in Talby. The values are presented in Figure 18 - Figure 21, Appendix 1, and Appendix 2.

Increased concentrations of total P in the effluent in Fågelsta towards the end of the period indicate a potential saturation of the filter (see also “6.4.1 Phosphorus profiles in the filter beds”). However, it should also be noted that inlet pipes to the filter bed were flushed 200501-26 and the effluent concentration of phosphorus might have been influenced. Although, the concentration of total phosphorus has increased at the end of the period studied, it is the phosphate ions that are precipitated by the calcium ions, Ca2+. The concentrations of phosphate phosphorus from both plants have been laying at 0 - 0.01 mg PO4-P/l during nearly the whole period of investigation. The precipitation is almost complete.

As can be seen in Figure 20 and Figure 21, the removal of phosphorus in the trickling filter is almost insignificant5. The relative large variations in inflow concentrations are mainly explained by the leakage from the toilet and water heater (in Talby) and the inflow of drainage water/stormwater (in Fågelsta). In March and April of 2004 a storage tank in Fågelsta leaked drainage water directly into the pump well before the trickling filter which diluted the samples after the trickling filter and in the effluent more than the samples in the influent.

5

The decrease in concentration over the trickling filter in Fågelsta winter 2003/2004 might be explain by a dilution due to leakage into the aforementioned storage tank.

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28

0.40 0.35 0.30

mg/l

0.25 Tot-Pg,out PO4-Pg,out

0.20 0.15 0.10 0.05 0.00 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

mg/l

Figure 18. Effluent concentrations of phosphorus from the plant in Fågelsta.

0.28 0.26 0.24 0.22 0.20 0.18 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00 May- Jul03 03

Tot-Pw,out Tot-Pd,out Tot-Pg,out PO4-Pd,out PO4-Pg,out

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 19. Effluent concentrations of phosphorus from the plant in Talby.

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29

P inf

20

P TF eff

P eff

18 16 mg P/l

14 12 10 8 6 4 2 0 May03

Jul03

Sep03

Nov03

Jan04

Mar- May04 04

Jul04

Sep04

Nov04

Jan05

Mar- May05 05

Figure 20. Concentrations of phosphorus in the plant in Fågelsta. The low influent concentration 2004-1214 is explained by dilution of water from snow melting. (TF = Trickling filter).

P inf

P TF eff

P eff

20 18 16

mg P/l

14 12 10 8 6 4 2 0 May03

Jul03

Sep03

Nov03

Jan04

Mar- May04 04

Jul04

Sep04

Nov04

Jan05

Mar- May05 05

Figure 21. Concentrations of phosphorus in the plant in Talby. (TF = Trickling filter).

6.4.1 Phosphorus profiles in the filter beds An investigation of the filter beds was performed in the Fågelsta plant 2004-06-17 and 200505-17, and 2004-06-17 and 2005-04-19 in the Talby plant. Water samples were taken at six different places in the filter bed, at the left and the right side of the filter bed in the inlet, in the middle, towards the outlet, and at two different levels, 0.1 metre and 0.5 metre over the bottom of the filter bed (see Figure 4). It was only possible to take samples just below the

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30 water surface at the right side of the filter bed in the influent point of the filter bed in the Fågelsta plant. The samples were analysed for total phosphorus, PO4-P, TOC, Kj-N, NH4-N, and (NO3+NO2)-N. Total nitrogen was calculated. The result from the study is presented in Table 9, Table 10, and in Appendix 4.

In Talby, the concentrations of phosphorus are generally (not including the inlet) below 1 mg tot-P/l in the upper part of the filter and only slightly higher in the bottom (Table 10). The phosphate concentrations are below 0.05 mg P/l in all samples (with exception for the inlet).

In Fågelsta, both the total phosphorus and phosphate concentrations are considerable higher in the bottom part of the filter (1 dm) than in the upper/middle part of the filter (5 dm), see Table 9. Furthermore, the concentrations are higher in all samples points in May 2005 compared to June 2004 (the inlet excepted). It is also noteworthy that the phosphate concentration is relatively high (0.66 – 2.5 mg PO4-P /l) in both samples towards the outlet in May 2005.

Thus, there is an indication that the bottom of the filter already is saturated by phosphorus.

Table 9. Concentrations of total phosphorus and phosphate phosphorus from grab water samples taken in the filter bed in Fågelsta at two levels, 0.1 metre and 0.5 metre over the bottom of the filter bed.

Fågelsta June 2004 Left, 5 dm Left, 1 dm

Inlet side Total P 7.2 160

PO4-P 4.7 2.4

Right, 5 dm Right, 1 dm May 2005 Left, 5 dm Left, 1 dm Right, 5 dm Right, 1 dm

Middle of filter Total P PO4-P 0.72 0.24 3.3 0.13

Towards the outlet Total P PO4-P 1.5 0.80 7.7 1.7

1.0 13

0.57 0.49

0.60 1.1

0.09 0.15

Total P

PO4-P

Total P

PO4-P

Total P

PO4-P

5.0 6.9

3.7 2.7

1.0 16

0.83

1.2 7.4

1.2 2.5

0.80 17

0.49

0.66 2.6

0.50 0.66

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31

Table 10. Concentrations of total phosphorus and phosphate phosphorus from grab water samples taken in the filter bed in Talby at two levels, 0.1 metre and 0.5 metre over the bottom of the filter bed.

Talby June 2004 Left, 5 dm Left, 1 dm

Inlet side Total P 6.1 39

PO4-P 2.8 3.3

Middle of filter Total P PO4-P 0.43 0.02 1.1 < 0.01

Towards the outlet Total P PO4-P 0.40 0.02 0.50 < 0.01

2.1 1.3

0.68 1.1

< 0.01 0.03

1.0 5.8

0.01 0.02

Total P

PO4-P

Total P

PO4-P

Total P

PO4-P

19 29

18 18

0.19 0.21

0.03 0.02

0.10 0.29

< 0.01 0.02

18

0.15 0.40

0.02 0.02

0.16 0.62

0.01 0.03

Right, 5 dm 8.0 Right, 1 dm 51 April 2005 Left, 5 dm Left, 1 dm

Right, 5 dm 16 Right, 1 dm 23

6.5

Nitrogen

The median concentrations of total nitrogen after the septic tank, after the trickling filter, and in the effluent were 68 mg N/l, 43 mg N/l, and 17 mg N/l in Fågelsta and 53 mg N/l, 45 mg N/l, and 21 mg N/l in Talby. In the same sample points the median concentrations of ammonium nitrogen were 56 mg NH4-N/l, 13 mg NH4-N/l, and 12 mg NH4-N/l in Fågelsta and 48 mg NH4-N/l, 11 mg NH4-N/l, and 14 mg NH4-N/l in Talby. The median concentrations of nitrate and nitrite in trickling filter effluent were in Fågelsta 18 mg (NO3+NO2)-N/l, and in Talby 30 mg (NO3+NO2)-N/l. The effluent concentrations were 2.6 mg (NO3+NO2)-N/l in Fågelsta and 7.5 mg (NO3+NO2)-N/l in Talby. The values are presented in Figure 22 - Figure 25.

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60 50

mg/l

40 30

Tot-Ng,out (NO3+NO2)-Ng,out NH4-Ng,out

20 10 0 May- Jul- Sep- Nov- Jan- Mar- May- Jul- Sep- Nov- Jan- Mar- May03 03 03 03 04 04 04 04 04 04 05 05 05

Figure 22. Effluent concentrations of nitrogen from the plant in Fågelsta.

60 50

mg/l

40 30 20

Tot-Nw,out Tot-Nd,out Tot-Ng,out (NO3+NO2)-Nw,out (NO3+NO2)-Nd,out (NO3+NO2)-Ng,out NH4-Nw,out NH4-Nd,out NH4-Ng,out

10 0 May- Jul- Sep- Nov- Jan- Mar- May- Jul- Sep- Nov- Jan- Mar- May03 03 03 03 04 04 04 04 04 04 05 05 05

Figure 23. Effluent concentrations of nitrogen from the plant in Talby.

In Fågelsta, the trickling filter effluent had very low nitrate concentration during 2004 due to the problems with a partly submerged trickling filter (see Figure 24 and “6.5.1 Nitrification”).

After the blockage, causing the problem, was removed and the treatment plant was repaired in the beginning of 2005, the nitrate concentrations increased to about 50 mg (NO3+NO2)-N/l.

In March and April of 2004 the storage tank in Fågelsta leaked drainage water directly into the pump well before the trickling filter which diluted the samples after the trickling filter and in the effluent more then the samples in the influent.

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100

80

mg N/l

60

40

N inf N TF eff NO3-N TF eff N eff NO3-N eff

20

0 May-03 Aug-03 Nov-03 Feb-04 May-04 Aug-04 Nov-04 Feb-05 May-05 Figure 24. Concentrations of nitrogen in the plant in Fågelsta.

120

mg N/l

100 80 60 40

N inf N TF eff NO3-N TF eff N eff NO3-N eff

20 0 May-03 Aug-03 Nov-03 Feb-04 May-04 Aug-04 Nov-04 Feb-05 May-05 Figure 25. Concentrations of nitrogen in the plant in Talby.

Since the environmental effects are related to the amount emitted, the loads to the recipient were also investigated. It is interesting to note that emissions of total nitrogen are rather equal for the plants, even if the load are about twice as high on the Fågelsta plant compared to the Talby plant. The median emission of nitrogen from the Fågelsta plant was 8.9 g N/d and from Talby 8.4 g N/d.

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30

load to the recipient, g tot-N/d

25

20

15

10

5

0 May/03 Jul/03 Sep/03 Nov/03 Jan/04 Mar/04 May/04 Jul/04 Sep/04 Nov/04 Jan/05 Mar/05 May/05

Figure 26. Nitrogen emissions in g N/d from the plant in Fågelsta.

load to the recipient, g tot-N/d

25

20

15

10

5

0 May/03 Jul/03 Sep/03 Nov/03 Jan/04 Mar/04 May/04 Jul/04 Sep/04 Nov/04 Jan/05 Mar/05 May/05

Figure 27. Nitrogen emissions in g N/d from the plant in Talby.

6.5.1 Nitrification Generally, the nitrification took place in the trickling filter and the denitrification in the filter bed. An exception is the period in Fågelsta when there was a 0.2 m water level in the bottom of the trickling filters as a result of a clogging of the pipes with sludge and earth after these two parallel filters. Thus, a combination of high flow probably causing a wash of out of

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35 biofilm and settling causing poor inclination of the pipes caused a blockage resulting in a partly submerged trickling filter. During this period, the nitrification took place in the upper 0.45 m of the trickling filters not soaked with water and denitrification took place in the lower 0.2 m of the trickling filter. This could be seen as a period from June to December 2004 with very low concentrations of nitrate and nitrite nitrogen after the trickling filter according to Figure 33.

The reduction of NH4-N over the trickling filer in g/(m2*d) as a function of influent NH4-N in g/(m2*d) could be seen in Figure 28 and Figure 30. Values from early samples show a lower degree of nitrification, indicating that the biofilm was not yet fully developed. There is a weak tendency that the degree of nitrification is reduced at higher nitrogen loading. It was not possible to show that the temperature had any impact on the degree of nitrification (Figure 29).

The reduction of NH4-N over the trickling filter is presented in Figure 31 and Figure 32. The median values of reduction were 77 % in Fågelsta and 76 % in Talby after 9 months of operation. The corresponding average values were 70 % in Fågelsta and 75 % in Talby.

Despite warmer water in the summer of 2004, the reduction of ammonium nitrogen was lower than usual in Fågelsta during that time, 40 - 60 %, see Figure 31. The conclusion is that it was problems with smaller volumes available for nitrification in the trickling filter as a result of clogging and inlet leakage with cold water that caused lower ammonium reduction. Excluding the period of submerged trickling filter in Fågelsta, the average reduction was 81 %.

The concentrations of ammonium and nitrate before and after the trickling filter in the two plants are also shown in Figure 33 and Figure 34. During the spring of 2005, the influent concentration of nitrogen increased significantly in Talby but the effluent concentrations of nitrate was relative constant.

8 7

g NH4-N red/(m2*d)

6 5 4 3 2

Values from the first samples (May - June 2003)

1 0 0

1

2

3

4 5 g NH4-N in/(m2*d)

6

7

8

Figure 28. Reduction of ammonium nitrogen as g/(m2·d) in the trickling filter as a function of the load of ammonium nitrogen to the trickling filter in the plant in Fågelsta.

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100

Nitrification, %

80

60

40

y = 0.0714x + 75.533 2 R = 0.0004

20

0 0

5

10

15

20

25

Temperature, C Figure 29. Nitrification (% of influent nitrogen not emitted as ammonia) versus water temperature in Talby. Values from the first 9 months excluded.

4.0 3.5

g NH4-N red/(m2*d)

3.0 2.5 2.0 1.5 1.0 0.5

First sample, May 2003

0.0 0.0

0.5

1.0

1.5

2.0 2.5 g NH4-N in/(m2*d)

3.0

3.5

4.0

Figure 30. Reduction of ammonium nitrogen as g/(m2路d) in the trickling filter as a function of the load of ammonium nitrogen to the trickling filter in the plant in Talby.

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37 100

reduction, %

80

60 NH4-Nred,bio 40

20

0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 31. Reduction of ammonium nitrogen in the trickling filter in the plant in FĂĽgelsta.

100

reduction, %

80

60 NH4-Nred,bio 40

20

0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 32. Reduction of ammonium nitrogen in the trickling filter in the plant in Talby.

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38 80 70 60

NH4-Nw,in NH4-Nd,in (NO3+NO2)-Nw,in (NO3+NO2)-Nd,in NH4-Nw,bf NH4-Nd,bf (NO3+NO2)-Nw,bf (NO3+NO2)-Nd,bf

mg N/l

50 40 30 20 10 0 May-03 Aug-03 Nov-03 Feb-04 May-04 Aug-04 Nov-04 Feb-05 May-05

Figure 33. Concentrations of ammonium nitrogen and nitrate and nitrite nitrogen before and after the trickling filter in the plant in Fågelsta.

120

100 NH4-Nw,in NH4-Nd,in (NO3+NO2)-Nw,in (NO3+NO2)-Nd,in NH4-Nw,bf NH4-Nd,bf (NO3+NO2)-Nw,bf (NO3+NO2)-Nd,bf

mg N/l

80

60

40

20

0 May-03 Aug-03 Nov-03 Feb-04 May-04 Aug-04 Nov-04 Feb-05 May-05

Figure 34. Concentrations of ammonium nitrogen and nitrate and nitrite nitrogen before and after the trickling filter in the plant in Talby.

6.6

Organic matter

The median concentrations of TOC after the septic tank, after the trickling filter, and in the effluent were 160 mg TOC/l, 41 mg TOC/l, and 9.5 mg TOC/l in Fågelsta and 57 mg TOC/l, 18 mg TOC/l, and 4.7 mg TOC/l in Talby. In the same sample points the median

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39 concentrations of COD were 520 mg COD/l, 120 mg COD/l, and 38 mg COD/l in Fågelsta and 190 mg COD/l, 58 mg COD/l, and 30 mg COD/l in Talby. And, finally, the median concentrations of BOD7 in these sample points were 240 mg BOD7/l, 36 mg BOD7/l, and 26 mg BOD7/l in Fågelsta and 58 mg BOD7/l, 12 mg BOD7/l, and 13 mg BOD7/l in Talby. The values are presented in Figure 35 - Figure 38 and in Appendix 1. The building up period of the biofilm in the trickling filter during 9 months after the start of operation December 200212-18 is obvious in all these figures.

In Fågelsta, the increased inflow during spring 2004 probably caused a wash out of biofilm from the trickling filter (indicated by a considerable amount of suspended solids in trickling filter effluent). This in combination with the settling problems caused a blockage of the trickling filter effluent. Thus, trickling filter effluent concentrations increased during spring 2004 – summer 2004. In spring 2005, after the pipes were re-arranged and flushed and the leakage was reduced, were the trickling effluent concentrations below 30 mg TOC/l.

160 140 120

mg/l

100 BOD7g,out CODg,out TOCg,out

80 60 40 20 0 May03

Jul03

Sep- Nov- Jan- Mar- May03 03 04 04 04

Jul04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 35. Effluent concentrations of organic matter from the plant in Fågelsta.

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40 250

200 BOD7d,out BOD7g,out CODw,out CODd,out CODg,out TOCw,out TOCd,out TOCg,out

mg/l

150

100

50

0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 36. Effluent concentrations of organic matter from the plant in Talby.

Inf.

250

TF eff.

Eff.

mg TOC/l

200 150 100 50 0 May03

Jul03

Sep03

Nov03

Jan04

Mar- May04 04

Jul04

Sep04

Nov04

Jan05

Mar- May05 05

Figure 37. Concentrations of TOC in the plant in Fågelsta. The increased concentration in trickling filter effluent during 2004 is explained by the wash out of biofilm ant the blockage of the pipe between the trickling filter and the filter bed. The relatively low influent concentration 2004-12-14 is explained by dilution of water from snow melting.

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41

Inf.

TF eff.

Eff.

250

mg TOC/l

200 150 100 50 0 May03

Jul03

Sep03

Nov03

Jan04

Mar- May04 04

Jul04

Sep04

Nov04

Jan05

Mar- May05 05

Figure 38. Concentrations of TOC in the plant in Talby.

The amount of organic matter discharged to recipient from the two plants was also investigated. The median load of organic matter from Fågelsta was 4.7 g TOC/d, 20.9 g COD/d, and 8.5 g BOD7/d, and from Talby 1.9 g TOC/d, 11.3 g COD/d, and 3.2 g BOD7/d.

This could be seen in Figure 39 and Figure 40. The starting up period in the two plants is obvious in these two figures.

80

load to the recipient, g/d

70 60 50 BOD7out,d CODout TOCout

40 30 20 10 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 39. Emission of organic matter in g/d from the plant in Fågelsta.

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42

70

load to the recipient, g/d

60 50 BOD7out,d CODout CODout,d TOCout TOCout,d

40 30 20 10 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 40. Emission of organic matter in g/d from the plant in Talby.

6.6.1

Degradation of organic matter in the trickling filter

Reduction of BOD7, TOC, and COD as g/(m2·d) in the trickling filter as a function of the load of BOD7, TOC, and COD, respectively, to the trickling filter in the plants are presented in Figure 41 - Figure 46. The corresponding reductions of BOD7, TOC, and COD in % in the trickling filter are presented in Figure 47 and Figure 48.

The median values of reduction of BOD7, TOC, and COD over the trickling filter after 9 months of operation were 85.7 % BOD7, 73.3 % TOC, and 79.0 %COD in Fågelsta and 87.9 % BOD7, 67.3 % TOC, and 71.4 %COD in Talby. The corresponding average values were 84.6 % BOD7, 63.3 % TOC, and 74.8 %COD in Fågelsta and 85.5 % BOD7, 67.6 % TOC, and 70.5 %COD in Talby.

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43 30

g BOD7 red/(m2*d)

25 20 15 10 5 0 0

5

10

15 g BOD7 in/(m2*d)

20

25

30

Figure 41. Reduction of BOD7 as g/(m2路d) in the trickling filter as a function of the load of BOD7 to the trickling filter in the plant in F氓gelsta.

4.5 4.0

g BOD7 red/(m2*d)

3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0

1

2

3 g BOD7 in/(m2*d)

4

5

6

Figure 42. Reduction of BOD7 as g/(m2路d) in the trickling filter as a function of the load of BOD7 to the trickling filter in the plant in Talby.

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44 18 16

g TOC red/(m2*d)

14 12 10 8 6 4 2 0 0

5

10

15 g TOC in/(m2*d)

20

25

30

Figure 43. Reduction of TOC as g/(m2路d) in the trickling filter as a function of the load of TOC to the trickling filter in the plant in F氓gelsta. The outlier (value 26.4 % reduction) comes from March 2004 when the leakage into the plant was large and the sample was filled with suspended solids.

6

g TOC red/(m2*d)

5

4

3

2

1

0 0

1

2

3 g TOC in/(m2*d)

4

5

6

Figure 44. Reduction of TOC as g/(m2路d) in the trickling filter as a function of the load of TOC to the trickling filter in the plant in Talby.

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45 60

g COD red/(m2*d)

50 40 30 20 10 0 0

10

20

30 g COD in/(m2*d)

40

50

60

Figure 45. Reduction of COD as g/(m2·d) in the trickling filter as a function of the load of COD to the trickling filter in the plant in Fågelsta.

14 12

g COD red/(m2*d)

10 8 6 4 2 0 0

1

2

3

4

5

6

7

8 9 10 11 g COD in/(m2*d)

12

13

14

15

16

17

18

Figure 46. Reduction of COD as g/(m2·d) in the trickling filter as a function of the load of COD to the trickling filter in the plant in Talby.

In Fågelsta, the removal efficiency decreased during 2004 due to the problems with a partly submerged trickling filter. After the blockage causing the problem was removed and the treatment plant was repaired in the beginning of 2005, the removal efficiency increased and was as high as before the problem occurred.

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46 100

reduction, %

80

60

BOD7 TOC COD

40

20

0 May/03 Jul/03 Sep/03Nov/03 Jan/04 Mar/04May/04 Jul/04 Sep/04Nov/04 Jan/05Mar/05May/05

Figure 47. Reduction of BOD7, TOC and COD in the trickling filter in the plant in FĂĽgelsta.

100

reduction, %

80

60

BOD7 TOC COD

40

20

0 May/03 Jul/03 Sep/03Nov/03 Jan/04 Mar/04May/04 Jul/04 Sep/04Nov/04 Jan/05Mar/05May/05

Figure 48. Reduction of BOD7, TOC and COD in the trickling filter in the plant in Talby.

6.7 Bacteria The concentrations of E. coli and fecal enterococci in the effluents from both plants have been below the limit of detection during the entire period of investigation. The good reduction of bacteria is probably due to a relative long hydraulic retention time in combination with a high

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47 pH (around 12 - 13 in the effluent). After the trickling filters but before the large filter bed the concentrations of E. coli and fecal enterococci as numbers/100 ml have approximately been between 104 and 105 in Fågelsta and approximately between 103 and 104 in Talby according to the diagrams in Figure 49 and Figure 50.

10000000 1000000

Numbers/100 ml

100000 10000 1000

E.coli Fecal Enterococci

100 10 1 May-03 Aug-03 Nov-03 Feb-04 May-04 Aug-04 Nov-04 Feb-05 May-05

Figure 49. Concentration of bacteria after the trickling filter in the plant in Fågelsta.

1000000

Numbers/100 ml

100000

10000

1000

100

10

1 May-03 Aug-03 Nov-03 Feb-04 May-04 Aug-04 Nov-04 Feb-05 May-05

Figure 50. Concentration of bacteria after the trickling filter in the plant in Talby.

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E.coli Fecal Enterococci

48

6.8

Alkalinity, Ca, and pH

The alkalinity as concentration of HCO3-, the concentration of calcium and pH in the effluent from the plants are shown in Figure 51 and Figure 52. The alkalinity and the concentration of calcium in Fågelsta have decreased noticeably during the period of investigation, maybe as a result of the problems with leakage into the plant flushing out the calcium ions. The pH has not decreased to the same extent. In Talby, there is only a slight decrease in the concentration of calcium, a small decrease in the alkalinity, and no significant change in pH. Despite the high pH, no obvious effect on vegetation was observed at effluent point in the ditch situated after the filter bed in Talby6.

14

4000

p

3500

12

mg HCO3/l, mg Ca/l

3000

10

2500 8 2000 6 1500 4

1000

2

500 0 May-03 Aug-03

0 Nov-03

Feb-04

May-04 Aug-04

Nov-04

Feb-05 May-05

Figure 51. Effluent concentrations of alkalinity, calcium, and pH in the plant in Fågelsta.

6

In Fågelsta is the effluent discharged to a drainage pipe.

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HCO3out Ca,out pHout

49

3500

14

3000

12

2500

10

2000

8

1500

6

1000

4

500

2

mg HCO3/l, mg Ca/l

pH

0 May-03

HCO3out Ca,out pHout

0 Aug-03

Nov-03

Feb-04

May-04

Aug-04

Nov-04

Feb-05

May-05

Figure 52. Effluent concentrations of alkalinity, calcium, and pH in the plant in Talby.

6.9 Comparison of grab sample and composite sample In the Talby plant, both composite samples, proportional to the flow, and grab samples were taken from the outlet of the plant. In the very beginning of the period investigated there was a small difference between the samples. The biofilm in the trickling filter was not fully developed and the concentrations of nitrogen and organic matter decreased rapidly. When “steady state” occurred, there was no significant difference between the grab samples and the composite samples in the outlet. This is shown in Figure 53 and Figure 54 where TOC and total nitrogen are compared.

25

mg TOCg,out/l

20

15

10

5

0 0

5

10

15

20

mg TOCw,out/l

Figure 53. Comparison between grab sample and composite sample in the outlet in Talby.

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25

50

60

mg Tot-Ng,out/l

50 40 30 20 10 0 0

10

20

30 mg Tot-Nw,out/l

40

50

60

Figure 54. Comparison between grab sample and composite sample in the outlet in Talby.

7 Discussion The average phosphorus removal for both plants, during the first 30 months of operation, was larger than 99 % and the median effluent concentrations were below 0.03 mg tot-P/l.

However, the evaluated period includes less than 20 % of the expected lifetime for the filter beds. Since the filter material is gradually saturated, it can be expected that the phosphorus concentration will increase in the future. Thus, the evaluation of the filter has to continue to determine the long term removal efficiency.

The phosphorus load in Talby corresponds to about two persons7, producing 60 % of their wastewater at home, and in Fågelsta three persons. Thus, the actual phosphorus load on the filter beds have been about 30 % of the design capacity and only 5 % of the assumed phosphorus adsorption capacity have been utilised. None the less, there are already indications of saturation in the bottom of the filter bed in Fågelsta. The samples taken in the filter bed in Fågelsta also indicate that there is an uneven distribution of wastewater and that the upper part of the filter bed is poorly utilised compared to lower part. Furthermore, alkalinity and calcium concentration have decreased significantly during the last year of operation in Fågelsta.

Nitrogen removal exceeded the goal of 50 % in both plants and the average value in Fågelsta was as high as 71 %. Despite a relative long period with a partly submerged trickling filter, a higher nitrogen load, and a lower temperature the nitrogen removal was higher in Fågelsta.

The nitrification was incomplete in both plants and about 20 % of the influent nitrogen was emitted as ammonium. Excluding periods with submerged filter, the degree of nitrification 7

Assuming 2.2 g P/person, d

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51 was slightly higher in Fågelsta. During periods with partly submerged filter in Fågelsta, the overall nitrogen removal efficiency did not decrease since the denitrification improved to the same extent as the nitrification was reduced. The better performance of the Fågelsta plant might depend on factors such loading frequency, distribution of the trickling water, and ventilation of the trickling filter. These parameters should be roughly equal for the plants, but they have not been thoroughly investigated. Other explanations are the different wastewater composition and the large variations in influent nitrogen concentration in Talby. Septic tank effluent in Talby has considerably lower TOC/N ratio than the wastewater in Fågelsta.

Furthermore, the alkalinity in the trickling filter effluent in Talby was considerably lower than in Fågelsta (see Appendix 5 and Appendix 6). However, there was still enough alkalinity in Talby for nitrification and pH in trickling filter effluent was generally above 7.

Removal of organic matter was generally above 90 % after the initial 9 months of operation and about 70 % was removed in the trickling filter. However, the trickling filters do not only reduce the organic content but they also produce a biofilm that might be sloughed off from time to time, especially at rapid increases in hydraulic loading as was the case in Fågelsta.

Thus, a capture for suspended solids before the filter bed could probably improve the robustness of the treatment plant (but the design will be more complicated).

The major problems in Fågelsta were high inflow due to leakage causing washout of biofilm from the trickling filter and settling of the trickling filter. These problems caused a blockage of the influent to the filter bed. In Talby, the major problem was a leakage from the filter bed.

It is possible that these sorts of problems can be avoided by another design and plant lay-out, e.g. by using smaller filter bed volumes in closed tanks. Such design would probably also result in a better utilisation of the filter material.

The plant should be regularly controlled to assure that there is no clogging of the spraying nozzle or any other blockages in the system. Thus, inspection pipes should be available at all critical positions. Otherwise, the process requires a minimum of operational control and maintenance.

An important aspect that has been partly evaluated in the Finnish project is the utilisation of phosphorus saturated filter material in agriculture. However, the practical applicability still has to be proved.

Economically, the treatment plants are characterised by relative high investment costs but relatively low operation costs. The investment cost can be significantly reduced if the volume of the filter bed is reduced. This will require a more frequent exchange of filter media and result in higher operational costs. However, by reducing the volume of phosphorus sorbing filter media, it will probably improve the possibilities to have a better overall utilisation of the media and thus reducing the total cost.

Environmentally, it is also important to consider the impact by producing and distribute the special fabricated filter material. There is for example a significant use of energy and calcium to produce the filter material. Thus, a thorough LCA is recommended.

Finally, it can be interesting to combine the investigated treatment plant with other solutions.

For example, the emission of nitrogen and the lifetime of the filter bed can be improved by using urine separating toilets.

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52

8 Conclusion The biological processes developed gradually and after 9 months the nitrogen removal was 50 % - 80 % and the removal of organic matter exceeded 90 %. The nitrification was incomplete in both plants and about 20 % of the influent nitrogen was emitted as ammonium. The reduction of phosphorus has during the two first years of operation exceeded 99 % and the effluent concentrations have generally been below 0.05 mg P/l. The concentrations of phosphate phosphorus in the effluent have been below 0.01 mg PO4-P/l during nearly the whole period of study. However, there are indications that one of the filter beds is partially saturated and effluent concentrations might increase in the near future. No E. coli nor Fecal Enterococci have been found in the effluents from the plants.

Economically, the treatment plants are characterised by relative high investment costs but relatively low operation costs. The installation and construction of the plant is rather complicated and requires special competence.

Environmentally, it is also important to consider the impact by producing and distribute the special fabricated filter material. Thus, a thorough LCA is recommended.

The plant should be regularly controlled to assure that there is no clogging of the spraying nozzle or any other blockages in the system. Thus, inspection pipes should be available at all critical positions. Otherwise, the process requires a minimum of operational control and maintenance.

9 References Hellström D., Jonsson L., Sjöström M., 2003, Bra Små Avlopp – Slutrapport: Utvärdering av 15 enskilda avloppsanläggningar, Stockholm Vatten rapport R nr 13, juni 2003.

Swedish EPA, 1987, Små avloppsanläggningar – hushållsspillvatten från högst, Allmänna Råd 87:6 (in Swedish).

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53

Appendix 1: Concentrations of N, P, organic matter and flow Table 11. Concentrations of substances May 2003 – May 2005 in the Fågelsta plant, as median, average, minimum, and maximum values. Flow through the plants in l/d.

Fågelsta plant Substance Flow, l/d Total P, mg/l PO4-P, mg/l Total N, mg/l (NO3+NO2)-N, mg/l NH4-N, mg/l TOC, mg/l COD, mg/l BOD7, mg/l

After septic tank Median/average, Min. – max.

468 / 536 109 – 1922 9.3 / 9.4 2.6 – 15 8.0 / 7.9 1.9 – 16 68 / 65 21 – 88 0.1 / 0.1 0.1 - 0.2 56 / 54 14 - 74 160 / 149 65 - 200 520 / 523 400 - 680 240 / 235 130 - 420

After trickling filter Median/average, Min. – max.

8.2 / 7.9 2.2 – 18 7.1 / 6.4 1.8 - 9.3 43 / 45 16 – 78 18 / 19 0.1 – 53 13 / 19 1.9 – 70 41 / 49 13 – 180 120 / 138 77 – 260 36 / 33 8 – 87

Effluent Median/average, Min. – max.

0.02 / 0.05 0.01 - 0.36 0.01 / 0.02 0.01 - 0.20 17 / 20 8.0 - 51 2.6 / 3.0 0.1 - 6.8 12 / 16 5.1 - 47 9.5 / 13 4.8 - 65 38 / 58 17 - 150 26 / 37 5 – 130

Table 12. Concentrations of substances May 2003 – May 2005 in the Talby plant, as median, average, minimum, and maximum values. Flow through the plants in l/d.

Talby plant Substance Flow, l/d Total P, mg/l PO4-P, mg/l Total N, mg/l (NO3+NO2)-N, mg/l NH4-N, mg/l TOC, mg/l COD, mg/l BOD7, mg/l

After septic tank Median/average, Min. – max.

370 / 407 79 – 974 6.3 / 7.9 1.7 - 19 4.5 / 6.1 1.6 - 17 53 / 55 12 - 120 0.1 / 0.1 0.1 - 0.1 48 / 49 10 - 110 57 / 62 15 - 140 190 / 222 110 - 420 58 / 56 10 - 120

After trickling filter Median/average, Min. – max.

5.0 / 6.6 1.9 – 17 4.8 / 6.2 2.1 – 17 45 / 49 14 – 106 30 / 30 6.9 – 56 11 / 17 0.4 – 66 18 / 19 7.3 – 48 58 / 68 35 - 160 12 / 11 4 - 26

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Effluent Median/average, Min. – max.

0.02 / 0.02 0.001 - 0.08 0.01 / 0.01 0.01 - 0.01 21 / 23 11 - 50 7.5 / 6.5 0.1 - 14 14 / 16 2.1 - 41 4.7 / 6.0 2.2 - 21 30 / 47 14 - 200 13 / 21 2 - 55

54

Appendix 2: Fågelsta (N, P, organic matter) 20 18 16 14 mg/l

12

Tot-Pw,in Tot-Pd,in PO4-Pd,in

10 8 6 4 2 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 55. Influent concentrations of phosphorus to the plant in Fågelsta.

20 18 16 14

mg/l

12

Tot-Pw,bf Tot-Pd,bf PO4-Pd,bf

10 8 6 4 2 0 May03

Jul03

Sep- Nov- Jan- Mar- May03 03 04 04 04

Jul04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 56. Concentrations of phosphorus between trickling filter and filter bed in the plant in Fågelsta.

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55

0.40 0.35 0.30

mg/l

0.25 Tot-Pg,out PO4-Pg,out

0.20 0.15 0.10 0.05 0.00 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 57. Effluent concentrations of phosphorus from the plant in Fågelsta.

100 90 80 70 mg/l

60

Tot-Nw,in Tot-Nd,in NH4-Nw,in NH4-Nd,in

50 40 30 20 10 0 May03

Jul03

Sep- Nov- Jan- Mar- May03 03 04 04 04

Jul04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 58. Influent concentrations of nitrogen to the plant in Fågelsta.

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56 90 80 70

mg/l

60 50 40 30

Tot-Nw,bf Tot-Nd,bf (NO3+NO2)-Nw,bf (NO3+NO2)-Nd,bf NH4-Nw,bf NH4-Nd,bf

20 10 0 May- Jul- Sep- Nov- Jan- Mar- May- Jul- Sep- Nov- Jan- Mar- May03 03 03 03 04 04 04 04 04 04 05 05 05

Figure 59. Concentrations of nitrogen between trickling filter and filter bed in the plant in Fågelsta (bf = before filter bed).

60 50

mg/l

40 30 20 10 0 May- Jul- Sep- Nov- Jan- Mar- May- Jul- Sep- Nov- Jan- Mar- May03 03 03 03 04 04 04 04 04 04 05 05 05

Figure 60. Effluent concentrations of nitrogen from the plant in Fågelsta.

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Tot-Ng,out (NO3+NO2)-Ng,out NH4-Ng,out

57

800 700 600 BOD7d,in CODw,in CODd,in TOCw,in TOCd,in

mg/l

500 400 300 200 100 0 May03

Jul03

Sep- Nov03 03

Jan- Mar- May04 04 04

Jul04

Sep- Nov04 04

Jan- Mar- May05 05 05

Figure 61. Influent concentrations of organic matter to the plant in Fågelsta.

300 250

mg/l

200

BOD7d,bf CODw,bf CODd,bf TOCw,bf TOCd,bf

150 100 50 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 62. Concentrations of organic matter between trickling filter and filter bed in the plant in Fågelsta (bf = before filter bed).

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58

160 140 120

mg/l

100 BOD7g,out CODg,out TOCg,out

80 60 40 20 0 May03

Jul03

Sep- Nov- Jan- Mar- May03 03 04 04 04

Jul04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 63. Effluent concentrations of organic matter from the plant in Fågelsta.

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59

Appendix 3: Talby (N, P, organic matter) 20 18 16 14 12 mg/l

Tot-Pw,in Tot-Pd,in PO4-Pd,in

10 8 6 4 2 0 May03

Jul03

Sep- Nov03 03

Jan04

Mar- May04 04

Jul04

Sep- Nov04 04

Jan- Mar- May05 05 05

Figure 64. Influent concentrations of phosphorus to the plant in Talby.

18 16 14 12 Tot-Pw,bf Tot-Pd,bf PO4-Pd,bf

mg/l

10 8 6 4 2 0 May03

Jul03

Sep- Nov03 03

Jan04

Mar- May04 04

Jul04

Sep- Nov04 04

Jan- Mar- May05 05 05

Figure 65. Concentrations of phosphorus between trickling filter and filter bed in the plant in Talby (bf = before filter bed).

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mg/l

60

0.28 0.26 0.24 0.22 0.20 0.18 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0.02 0.00 May- Jul03 03

Tot-Pw,out Tot-Pd,out Tot-Pg,out PO4-Pd,out PO4-Pg,out

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 66. Effluent concentrations of phosphorus from the plant in Talby.

140 120

mg/l

100 Tot-Nw,in Tot-Nd,in NH4-Nw,in NH4-Nd,in

80 60 40 20 0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 67. Influent concentrations of nitrogen to the plant in Talby.

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

61 120 100

mg/l

80 60 40

Tot-Nw,bf Tot-Nd,bf (NO3+NO2)-Nw,bf (NO3+NO2)-Nd,bf NH4-Nw,bf NH4-Nd,bf

20 0 May- Jul- Sep- Nov- Jan- Mar- May- Jul- Sep- Nov- Jan- Mar- May03 03 03 03 04 04 04 04 04 04 05 05 05

Figure 68. Concentrations of nitrogen between trickling filter and filter bed in the plant in Talby (bf = before filter bed).

60 50

mg/l

40 30 20 10 0 May- Jul- Sep- Nov- Jan- Mar- May- Jul- Sep- Nov- Jan- Mar- May03 03 03 03 04 04 04 04 04 04 05 05 05

Figure 69. Effluent concentrations of nitrogen from the plant in Talby.

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

Tot-Nw,out Tot-Nd,out Tot-Ng,out (NO3+NO2)-Nw,out (NO3+NO2)-Nd,out (NO3+NO2)-Ng,out NH4-Nw,out NH4-Nd,out NH4-Ng,out

62

450 400 350

mg/l

300

BOD7d,in CODw,in CODd,in TOCw,in TOCd,in

250 200 150 100 50 0 May03

Jul03

Sep- Nov03 03

Jan04

Mar- May04 04

Jul04

Sep- Nov04 04

Jan- Mar- May05 05 05

Figure 70. Influent concentrations of organic matter to the plant in Talby.

180 160 140 120

BOD7d,bf CODw,bf CODd,bf TOCw,bf TOCd,bf

mg/l

100 80 60 40 20 0 May03

Jul03

Sep- Nov- Jan- Mar- May03 03 04 04 04

Jul04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 71. Concentrations of organic matter between trickling filter and filter bed in the plant in Talby (bf = before filter bed).

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

63 250

200 BOD7d,out BOD7g,out CODw,out CODd,out CODg,out TOCw,out TOCd,out TOCg,out

mg/l

150

100

50

0 May- Jul03 03

Sep- Nov- Jan- Mar- May- Jul03 03 04 04 04 04

Sep- Nov- Jan- Mar- May04 04 05 05 05

Figure 72. Effluent concentrations of organic matter from the plant in Talby.

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

64

Appendix 4: Analyses from sampling in filter beds Table 13. Results from sampling in Fågelsta filter bed, 17 June 2004.

TOC

PO4-P

Tot-P

Kj-N

NH4-N

NO3-N

Tot-N

Location

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

In, left, 0.1 m

170

2,4

160

57,9

17,4

0,1

58

In, left, 0.5 m

36

4,7

7,2

19,0

13,6

0,7

20

In, right, 0.9 m

32

3,8

6,2

16,5

11,9

0,1

17

Middle, left, 0.1 m

20

0,13

3,3

17,2

14,7

1,5

19

Middle, left, 0.5 m

14

0,24

0,72

16,0

14,6

2,9

19

Middle, right, 0.1 m

52

0,49

13

23,7

17,7

0,3

24

Middle, right, 0.5 m

18

0,57

1,0

18,2

16,3

1,1

19

Out, left, 0.1 m

27

1,7

7,7

7,3

3,4

13,3

21

Out, left, 0.5 m

11

0,80

1,5

4,2

3,0

14,3

19

Out, right, 0.1 m

8,6

0,15

1,1

3,9

3,0

5,7

10

Out, right, 0.5 m

8,1

0,09

0,60

2,9

2,1

7,1

10

Table 14. Results from sampling in Fågelsta filter bed, 17 May 2005.

TOC

PO4-P

Tot-P

Kj-N

NH4-N

NO3-N

Tot-N

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

In, left, 0.1 m

78

2.7

6.9

31.2

13.6

5.5

37

In, left, 0.5 m

36

3.7

5.0

21.6

13.5

4.7

26

In, right, 0.9 m

17

3.6

4.1

14.8

12.1

0.5

15

Middle, left, 0.1 m

37

16

18.1

12.6

3.5

22

Middle, left, 0.5 m

8.9

1.0

7.0

5.7

7.9

15

Middle, right, 0.1 m

54

17

25.8

18.5

1.7

28

Middle, right, 0.5 m

11

0.49

0.80

10.6

9.0

3.9

15

Out, left, 0.1 m

28

2.5

7.4

5.0

1.3

11

16

Out, left, 0.5 m

5.4

1.2

1.2

1.4

0.3

12

13

Out, right, 0.1 m

11

0.66

2.6

6.1

4.8

5.4

12

Out, right, 0.5 m

5.5

0.50

0.66

2.7

1.8

5.9

9

Location

0.83

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65

Table 15. Results from sampling in Talby filter bed, 17 June 2004.

TOC

PO4-P

Tot-P

Kj-N

NH4-N

NO3-N

Tot-N

Location

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

In, left, 0.1 m

120

3,3

39

22,4

5,0

4,7

27

In, left, 0.5 m

20

2,8

6,1

6,4

3,7

6,4

13

In, right, 0.1 m

79

1,3

51

12,8

4,0

6,3

19

In, right, 0.5 m

15

2,1

8,0

5,8

3,7

6,6

12

Middle, left, 0.1 m

9

<0,01

1,1

5,2

2,7

10

16

Middle, left, 0.5 m

5,4

0,02

0,43

2,8

2,4

10

13

Middle, right, 0.1 m

7,4

0,03

1,1

4,5

3,8

11

16

Middle, right, 0.5 m

6,1

<0,01

0,68

3,4

3,1

11

15

Out, left, 0.1 m

4,7

<0,01

0,50

1,8

0,8

11

13

Out, left, 0.5 m

4,1

0,02

0,40

1,0

0,7

11

12

Out, right, 0.1 m

9,9

0,02

5,8

1,7

0,7

13

15

Out, right, 0.5 m

4,7

0,01

1,0

1,1

0,6

13

14

Table 16. Results from sampling in Talby filter bed, 19 April 2005.

TOC

PO4-P

Tot-P

Kj-N

NH4-N

NO3-N

Tot-N

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

mg/l

In, left, 0.1 m

66

18

29

66

55

12

78

In, left, 0.5 m

42

18

19

60

54

13

73

In, right, 0.1 m

46

18

23

59

51

20

79

In, right, 0.5 m

33

16

49

51

20

69

Middle, left, 0.1 m

14

0,02

0,21

43

41

19

62

Middle, left, 0.5 m

12

0,03

0,19

41

39

19

60

Middle, right, 0.1 m

13

0,02

0,40

44

42

17

61

Middle, right, 0.5 m

12

0,02

0,15

42

40

18

60

Out, left, 0.1 m

8,2

0,02

0,29

15

12

26

41

Out, left, 0.5 m

5,5

<0,01

0,10

7,5

6

27

35

Out, right, 0.1 m

14

0,03

0,62

22

19

20

42

Out, right, 0.5 m

5,5

0,01

0,16

20

19

20

40

Location

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66

Appendix 5: Analyses data sheet - Fågelsta Date

Q outlet SS in SS TF l/s mg/l mg/l 19-05-03 363 72 45 20-05-03 462 20-05-03 02-06-03 577 84 30 03-06-03 470 03-06-03 16-06-03 1 17-06-03 394 17-06-03 30-06-03 500 130 22 01-07-03 363 01-07-03 28-07-03 434 100 29-07-03 406 29-07-03 11-08-03 571 97 16 12-08-03 342 12-08-03 25-08-03 361 180 22 26-08-03 741 26-08-03 08-09-03 586 170 17 09-09-03 449 09-09-03 22-09-03 664 150 27 23-09-03 489 23-09-03 06-10-03 302 28-09-03 624 07-10-03 20-10-03 706 110 10 21-10-03 665 21-10-03 03-11-03 735 94 11 04-11-03 698 04-11-03 12-11-03 17-11-03 741 18-11-03 679 18-11-03 01-12-03 650 90 32 02-12-03 607 02-12-03 03-12-03 15-12-03 781 16-12-03 675 16-12-03 26-01-04 610 84 27-01-04 609 27-01-04 28-01-04 09-02-04 807 10-02-04 1189 10-02-04 23-02-04 711 68 65 24-02-04 607 24-02-04 25-02-04 08-03-04 330 09-03-04 574 09-03-04 22-03-04 2150 38 230 23-03-04 1922 23-03-04 24-03-04 05-04-04 573 06-04-04 780 06-04-04 19-04-04 626 80 49 20-04-04 498 20-04-04 03-05-04 623 76 68 04-05-04 528

SS out Tot P in Tot P TF mg/l mg/l mg/l 9,9 9,4 9,3 8,5 7 9,8 8,5 9,3 9,0 9 11

Tot P out PO4 in PO4 TF mg/l mg/l mg/l 7,9 7,4 0,02 9,6 0,02

10

8

71

12 9,8

9,3 9,5

10 9,5

7,7 8,8

12 13

7,7 8,2

9,6 8,6

6,9 6,2

9,5 7,3

5,5 5,7

14 13

9,7 7,5

14

8,3

8,7

0,01

6

26

10

7,3

5,9

5,1

6,3

5,0

11

9,2

< 0,01

5

11 14

58 59

7,4 8,4

40 46

8,9 8,0

9,3 9,6

12 12

7,7 8,0

4

41 44

8,1 7,8

56 57

14 12

63

4

11

10

8,4

62 64

12 11

9,6

7,0

66 65

16 14

67

15

16

56

54

0,8 < 0,5

24

< 0,5 < 0,5

28 33

< 0,5 < 0,5

24 29

1,4

2,2

2,6

3,0

2,6

28 14

7,1

51

3,3

10

34

8,6 5,0

1,9

56

8,6

23

17

1,9

27 12

1,9

1,2

2,3 26

6,8

< 0,01

0,05

11

11 9,6

29

5,6

0,03

2,5

15 8,0

9,3

8,1 44

1,7 21 21

8,7

0,06 12 12

2,3

14

13

39

12

7,5 48

9,2 7,6

2,8

14 9,4

6,1 8,0

35 12

2,5

18

11 6,2

1,1

28

11

< 0,01

11 12

21 17

13

< 0,01

8,1

< 0,5 < 0,5

1,8

8,1

4

2,4 6,9

22 17

33

10

0,01

12

< 0,5 < 0,5

0,8

6,3

0,02

11 9,2

22 24

12

12

5

7,2

< 0,5 < 0,5

1,5

12

0,01 11 9,3

58 51

13

0,01

15

< 0,5 < 0,5

< 0,5

17

8,4 6,6 7,1

48 49

24

0,01 18 11

< 0,5 < 0,5

< 0,5

28

0,01

13

23 22

30

0,01

3

< 0,5 < 0,5

33

0,01 14 13

< 0,5

35

< 0,01

10

< 0,5

38

< 0,01

0,01

6

60 62

< 0,01

0,01

8

30 35

< 0,01

0,01

9

66 69

< 0,01

0,01

NO3 TF NO3 out mg/l mg/l < 0,5 < 0,5 < 0,5 < 0,5 < 0,5 < 0,5

43

0,01 7,6

NH4+ out NO3 in mg/l mg/l < 0,5 < 0,5 47 < 0,5 < 0,5 43

59

< 0,01

0,01

14

PO4 out NH4+ in NH4 TF mg/l mg/l mg/l 69 66 68 60 < 0,01 67 65 73 70 < 0,01

5,5 8,3

1,8

9,3

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56

22

9,6

67 Date 04-05-04 05-05-04 17-05-04 18-05-04 18-05-04 31-05-04 01-06-04 01-06-04 02-06-04 15-06-04 23-06-04 28-06-04 29-06-04 29-06-04 30-06-04 12-07-04 13-07-04 13-07-04 09-08-04 10-08-04 10-08-04 23-08-04 24-08-04 24-08-04 06-09-04 07-09-04 07-09-04 16-09-04 20-09-04 21-09-04 21-09-04 22-09-04 04-10-04 05-10-04 05-10-04 18-10-04 19-10-04 19-10-04 19-10-04 01-11-04 02-11-04 02-11-04 15-11-04 16-11-04 16-11-04 29-11-04 30-11-04 30-11-04 13-12-04 14-12-04 14-12-04 31-01-05 01-02-05 01-02-05 14-02-05 15-02-05 15-02-05 28-02-05 01-03-05 01-03-05 14-03-05 15-03-05 15-03-05 28-03-05 29-03-05 29-03-05 11-04-05 12-04-05 12-04-05 25-04-05 26-04-05 26-04-05 09-05-05 10-05-05 10-05-05 11-05-05 23-05-05 24-05-05 24-05-05 13-06-05 14-06-05 14-06-05

Q outlet SS in SS TF l/s mg/l mg/l

SS out Tot P in Tot P TF mg/l mg/l mg/l 27

392 483

8,8

Tot P out PO4 in PO4 TF mg/l mg/l mg/l 0,03

PO4 out NH4+ in NH4 TF mg/l mg/l mg/l < 0,01

9,9

48

22

0,02 0 320

9,4

453 426

67

36

7,8 7,0

265 400

63

1,7

0,01

7,9

3,4

7,5 44

19

< 0,01

8,8

7,5

54

32

109

90

8,1 7,5

7,0

43

8,0 6,9

10 296 286

18

4,8

120

61

11 8,9

46

15 231 260

57

96

39

9,5 9,8

365 383

61

34

67

92

20

8,2 12

339 386

80

130

69

74

36

31 447 1129

38

71

5,7

6,4

100

14

8,1 8,6

35

< 0,01

2,4

366 372

4,4

33

83

33

10 10

822 552

100

14

49

6,1

0,01

67 677 910

6,5

74

5,5

4,3

77

120

6,1 6,3

12

0,20

3,2

215 185

3,5

36

86

21

6,9 9,2 24

5,0 25

12 4,4

5,2

3,4 44

13

0,01

4,9

23 13

55

6,2 6,5

6,8 29

5,9

13

0,15 2018 671

53

12

0,08

7,9

6,0

10 30

3,3

22

52

4,6 72

4,1 3,9

5,7

12

0,11 275 436

53

9,5

< 0,01

0,25 201 400

3,9

5,6

0,36 4,1

45

13 10

4,8 6,3

3,9

16 57

0,14 5,6 9,6

18

1,8

3,5

38

5,4

15 5,7

6,4 5,4

6,7 12

7,2

0,09 292 351

1,6

15

0,03 9,4

6,4

10 14

4,6

14

1,3

4,8 71

2,2 2,2

5,1

8,5

0,09 391 109

0,6

35

< 0,01

0,19 532 697

5,0

8,8

0,10 2,6

1,3

11 6,6

7,8 9,2

3,8

10

0,08 8,3 10

1,9

7,2

10

29

3,8

12 7,2

9,3 12

1,5

33

0,03 352 413

2,8

11

0,04

12

1,0

7,5

12

10

2,4

13 8,2

8,9 8,9

1,4

30

0,01 443 315

2,4

13

0,02

11

1,2

18

< 0,01

8,1

9,4 9,1

3,0

5,5

0,02 207 302

1,3

13

0,01 8,4

3,1

12

0,02 298 374

0,5 9,8

0,02 419 381

2,6 6,5

0,02

8,4

28

2,2

0,02

7,1 18

9

4,6 5,5

9,3

23

NH4+ out NO3 in NO3 TF NO3 out mg/l mg/l mg/l mg/l 5,1 2,1

4,7

28 11

5,3

5,5

5,6 73

0,20

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

0,07

26

11 9,0

6,2

68 Date

TotN in TotN TF mg/l mg/l 19-05-03 82 74 20-05-03 80 68 20-05-03 02-06-03 84 72 03-06-03 82 78 03-06-03 16-06-03 17-06-03 84 67 17-06-03 30-06-03 84 56 01-07-03 82 64 01-07-03 28-07-03 77 63 29-07-03 73 67 29-07-03 11-08-03 72 68 12-08-03 69 63 12-08-03 25-08-03 58 34 26-08-03 49 37 26-08-03 08-09-03 56 34 09-09-03 54 30 09-09-03 22-09-03 70 39 23-09-03 66 33 23-09-03 06-10-03 28-09-03 74 40 07-10-03 20-10-03 75 43 21-10-03 71 48 21-10-03 03-11-03 78 43 04-11-03 76 46 04-11-03 12-11-03 17-11-03 18-11-03 78 54 18-11-03 01-12-03 02-12-03 65 42 02-12-03 03-12-03 15-12-03 16-12-03 65 44 16-12-03 26-01-04 27-01-04 62 50 27-01-04 28-01-04 09-02-04 10-02-04 44 16 10-02-04 23-02-04 24-02-04 59 36 24-02-04 25-02-04 08-03-04 09-03-04 69 56 09-03-04 22-03-04 23-03-04 35 36 23-03-04 24-03-04 05-04-04 06-04-04 35 42 06-04-04 19-04-04 20-04-04 56 36 20-04-04 03-05-04 04-05-04 68 42

TotN out COD in COD TF mg/l mg/l mg/l 680 250 680 250 51 550 170 600 180 47 610

COD out BOD7 in BOD7 TF BOD7 out TOC in TOC TF mg/l mg/l mg/l mg/l mg/l mg/l 420 52 210 73 200 61 150 56 310 50 180 53 200 63 140 92

200

46

130 400 520

100 160

340 480

100 120

330 410

80 88

440 450

87 120

440 570

82 130

450 600

85 99

41

150

36

130

8

160

19

190

21

210

16

270

25

110

38

630

30 34

130 130

25 28

140 140

32 33

140 160

25 35

150 190

29 32

67 77

450 510

72 78

17

48

12,42

12,43 7,76

7,97 12,71

7,67

7,59

7,67

7,67

7,70

7,84

7,68

7,76

12,43

20

12,63

16

12,62

16 190

35

160 170

23 25

140 160

24 25

12,78

13

37

16

7,89

65

21

38 500 540

7,53

12,59 7,93

7,91

7,85

7,82

11

32 23 140

12,97

9,5 8,7

12,95 7,84

7,53

7,88

7,63

38

16

8,6 510 480

57 93

17

270

9 160

28

13,00

29

11 77

8,8 8,5

12,93 7,81

490

110

19

pH out

26

26

100

pH TF

33

30

38

20

100 140

pH in

43

41

54

26

59 47

46

67

31

120 170

46

67

34

61

130

83

36

190 88

TOC out mg/l

160

7,69

35

31

8,4

13,08 7,70

160

34

15

7,2

13,12 7,72

110

13

17

8,6 240 400

18

39

84

130 28

7,34

25

12

8,2

140

13,08 8,01

7,86

7,38

6,99

82

15

7,3 97

13,24

82

13

7,8

85

12,74 7,95

7,37

7,83

7,83

8,02

7,75

130

11

6,2 160

12,92

42

8,5

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

13,08 7,95

5,4 160

77

13,03

69 Date 04-05-04 05-05-04 17-05-04 18-05-04 18-05-04 31-05-04 01-06-04 01-06-04 02-06-04 15-06-04 23-06-04 28-06-04 29-06-04 29-06-04 30-06-04 12-07-04 13-07-04 13-07-04 09-08-04 10-08-04 10-08-04 23-08-04 24-08-04 24-08-04 06-09-04 07-09-04 07-09-04 16-09-04 20-09-04 21-09-04 21-09-04 22-09-04 04-10-04 05-10-04 05-10-04 18-10-04 19-10-04 19-10-04 19-10-04 01-11-04 02-11-04 02-11-04 15-11-04 16-11-04 16-11-04 29-11-04 30-11-04 30-11-04 13-12-04 14-12-04 14-12-04 31-01-05 01-02-05 01-02-05 14-02-05 15-02-05 15-02-05 28-02-05 01-03-05 01-03-05 14-03-05 15-03-05 15-03-05 28-03-05 29-03-05 29-03-05 11-04-05 12-04-05 12-04-05 25-04-05 26-04-05 26-04-05 09-05-05 10-05-05 10-05-05 11-05-05 23-05-05 24-05-05 24-05-05 13-06-05 14-06-05 14-06-05

TotN in TotN TF mg/l mg/l

59

TotN out COD in COD TF mg/l mg/l mg/l 8,0

COD out BOD7 in BOD7 TF BOD7 out TOC in TOC TF mg/l mg/l mg/l mg/l mg/l mg/l

37

150

42

600

260

8,9

190 17

50

130

43

150

28

170

170

38

130

7,73

7,82

7,61

7,65

12,97

12,88

56 10

340 400

150 190

160

40

37

100 130

43 60

13

48

7,92

7,97

10

140

71

170 170

68 50

12,68 8,07

8,02

7,77

7,92

7,87

7,77

7,71

7,61

8,01

7,55

7,65

7,08

9,6 550 550

44

12,72

54

17 82

6,9

11

17

79

12,92

11

27

44

14

69

17

72

12,86

10

17 67

5,5

79

17 56

7,77

8,3

16 57

7,94

pH out 12,88

180

14

66

pH TF

84

10

13

54

pH in

69

8,1 78

TOC out mg/l 4,8

220 160

16

260

87

32

11

12,66

9,5 12,62

88

45

180

50

17 83

13

44

180

47

110 160

50 50

16 83

10 400 500

44

190 170

19 21

220

38

40

9

21

65

11

32

92

8,4

55

140

62

140

160

23

66 100

240

14

120 170

25 29

29

5

35

78

68

7,48

7,18

7,80

7,87

7,78

7,86

12,58

11,96

14

120

24

110 120

290 < 25

36

130 130

33 40

6

12,00

47

180

44

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

12,10 7,62

7,32

7,29

7,12

45 7,2

180 16

12,01

7,0

18 85

7,00

7,2 440 420

19

7,94

12,71

7,4

34

41

7,45

7,9

19 52

8,16

13,10

20

18 46

7,29

8,5 400 540

18 36

8,05 7,4

64

66

7,28

8,1

19 78

8,13 25

20 85

12,35

23

20 68

12,61

29

20 62

12,51

11

21 42

12,56

11,95

55 7,7

11,66

70 Cond. Cond. Cond.

In TF Out 19-05-03 150 152 20-05-03 20-05-03 990 02-06-03 143 146 03-06-03 03-06-03 1000 16-06-03 17-06-03 17-06-03 955 30-06-03 138 124 01-07-03 01-07-03 936 28-07-03 138 29-07-03 29-07-03 885 11-08-03 127 116 12-08-03 12-08-03 894 25-08-03 122 106 26-08-03 26-08-03 897 08-09-03 123 104 09-09-03 09-09-03 904 22-09-03 141 115 23-09-03 23-09-03 917 06-10-03 28-09-03 07-10-03 902 20-10-03 134 107 21-10-03 21-10-03 920 03-11-03 130 107 04-11-03 04-11-03 927 12-11-03 17-11-03 18-11-03 18-11-03 01-12-03 02-12-03 02-12-03 03-12-03 15-12-03 16-12-03 16-12-03 26-01-04 27-01-04 27-01-04 28-01-04 09-02-04 10-02-04 10-02-04 23-02-04 120 96,3 24-02-04 24-02-04 844 25-02-04 08-03-04 09-03-04 09-03-04 22-03-04 23-03-04 23-03-04 24-03-04 05-04-04 06-04-04 06-04-04 19-04-04 20-04-04 20-04-04 03-05-04 04-05-04

Date

Alk. in Alk. TF 580

690

520

580

620

Alk. out

Ca out mg/l

Mg out mg/l

Fe out mg/l

Al out mg/l

3400

860

<1

0,021

<1

3000

850

<1

0,020

<1

2900

810

<1

0,020

<1

2900

740

<1

0,020

<1

2700

750

2700

700

2800

600

2800

600

2600

570

2900

610

2600

650

2600

680

Enteroc.

TF

Enterococci out

out pre filter

E-coli

45000

< 10

81600

25600

< 10

41060

360

600

510

150

550

320

480

310

380

520

240

460

220

530

190 2700

800

<1

0,055

<1

380 2400

780 < 10

450

180 2500

730

<1

0,120

<1 18500

140

< 10

110 1800

440 < 10

440

260

580

420

2000

650

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

309000

E-coli Comments out 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample

71 Date 04-05-04 05-05-04 17-05-04 18-05-04 18-05-04 31-05-04 01-06-04 01-06-04 02-06-04 15-06-04 23-06-04 28-06-04 29-06-04 29-06-04 30-06-04 12-07-04 13-07-04 13-07-04 09-08-04 10-08-04 10-08-04 23-08-04 24-08-04 24-08-04 06-09-04 07-09-04 07-09-04 16-09-04 20-09-04 21-09-04 21-09-04 22-09-04 04-10-04 05-10-04 05-10-04 18-10-04 19-10-04 19-10-04 19-10-04 01-11-04 02-11-04 02-11-04 15-11-04 16-11-04 16-11-04 29-11-04 30-11-04 30-11-04 08-12-04 13-12-04 14-12-04 14-12-04 31-01-05 01-02-05 01-02-05 14-02-05 15-02-05 15-02-05 28-02-05 01-03-05 01-03-05 14-03-05 15-03-05 15-03-05 28-03-05 29-03-05 29-03-05 11-04-05 12-04-05 12-04-05 13-04-05 25-04-05 26-04-05 26-04-05 09-05-05 10-05-05 10-05-05 11-05-05 23-05-05 24-05-05 24-05-05 13-06-05

Cond. Cond. Cond.

In TF Out

Alk. in Alk. TF

Alk. out

Ca out mg/l

Mg out mg/l

Fe out mg/l

Al out mg/l

Enteroc.

TF

Enterococci out

2400 < 10

756

2200

680

<1

0,130

<1 48800

< 10 < 10

450

330 1800

470 < 10

450

390 2200

620

< 10 136

119

520

460

471

155

134

1300

620

123

1000

480

480

520

350

259

240

103

94,7

88,9

650

110

400

130

460

1,4 24194

< 10

220

630

120

660

130

<1

1,6

0,370

24192

< 10

0,340

30760

< 10

106

< 10

695

< 10

1,8

1,4

810

170

490

110

280

58

5,2

0,190

<1

250

176

480

330

0,370

78

112

116

<1

580

340

129

300

83

1,4

0,220

<1

300

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

E-coli

E-coli Comments out grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 14 day sample grab sample 2280000 < 100 grab sample grab sample < 100 grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 14 day sample grab sample < 100 grab sample 2 day sample 12 day sample grab sample 43520 < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 98040 < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 19863 < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 14 day sample grab sample < 100 grab sample 5900 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 1350 2 day sample 14 day sample grab sample 2 day sample

out pre filter

72

Appendix 6: Analyses data sheet - Talby Sampling point no: Date

Q outlet l/s 19-05-03 304 20-05-03 288 20-05-03 02-06-03 405 03-06-03 333 03-06-03 16-06-03 428 17-06-03 429 17-06-03 30-06-03 413 01-07-03 490 01-07-03 28-07-03 354 29-07-03 417 29-07-03 11-08-03 535 12-08-03 468 12-08-03 25-08-03 140 26-08-03 170 26-08-03 08-09-03 161 09-09-03 278 09-09-03 22-09-03 500 23-09-03 347 23-09-03 06-10-03 370 07-10-03 371 07-10-03 20-10-03 386 21-10-03 368 21-10-03 03-11-03 418 04-11-03 456 04-11-03 12-11-03 17-11-03 577 18-11-03 485 18-11-03 01-12-03 470 02-12-03 462 02-12-03 03-12-03 15-12-03 435 16-12-03 452 16-12-03 26-01-04 598 27-01-04 450 28-01-04 09-02-04 759 10-02-04 718 10-02-04 23-02-04 744 24-02-04 809 24-02-04 25-02-04 08-03-04 731 09-03-04 774 09-03-04 22-03-04 853 23-03-04 844 23-03-04 24-03-04 05-04-04 881 06-04-04 974 06-04-04 19-04-04 523 20-04-04 814 20-04-04 03-05-04 865

1

2

SS in SS TF mg/l mg/l 8

3 SS out mg/l 24

28

7

12 61

58

6

10 62

1

2

Tot P in Tot P TF mg/l mg/l 3,5 2,8 3,7 2,8 3,7

2,7 3,5

3,3 3,1

2,9 2,8

3,8 3,6

3,1 3,0

2,5 3,4

1,9

3,5 3,2

2,7

7,5 5,7

4,6 3,8

5,0

6,2 5,7

8,0 9,1

6,8 7,2

7,2 8,4

6,0 6,6

7,9 7,5

6,8 5,7

7,7 7,4

6,3 6,0

7,7

6,3

5,7 6,4

5,1 5,1

6,2

4,8

6,4 6,6

5,1 4,7

5,7

4,7

5,2 5,1

4,3 4,2

4,9

4,9

2,8 3,2

3,0 2,8

9 39 8 74 56 70

22

10 6 16 10

59

7

5 75

43

6

5 160

56

60

5

3 44 6

60

3 5

47

27

3

2

23

77 7

13

5

48 7

16

7

2

3

72 6 36

3,2

3,2

2,8 2,6

2,8 2,8

2,0

2,5

3 Tot P out mg/l 0,02 0,08 0,01 0,01 0,03 0,01 0,02 0,02 0,01 0,01 0,03 0,04 0,01 0,01 0,01 0,01 0,02 0,01 0,10 < 0,01 0,01 0,01 0,04 0,01 0,01 0,02 < 0,01 0,01 0,01 0,01 0,02 0,03 < 0,01

1

2

PO4 in PO4 TF mg/l mg/l 2,8

2,4

2,7

2,5

2,7

2,5

3,0

2,1

3,0

4,1

5,9

3

1

2

+

PO4 out NH4 in NH4 TF mg/l mg/l mg/l < 0,01 26 41 36 < 0,01 0,01 21 9,1 36 16 < 0,01 0,01 27 8,3 26 8,1 0,01 23 5,6 28 8,2 0,01 < 0,01 18 25 4,4 < 0,01 < 0,01 20 16 3,8 < 0,01 < 0,01 11 36 10 < 0,01 57 15 57 18 < 0,01 < 0,01 53 25 69 27

3 +

NH4 out mg/l 27 22 30 28 27 36 38 34 42 39 41 40 20 25 19 18 20 18 15 15 16 11 13 12 13 12 14 13 13 14 9,0 13 14

1

2

3

NO3 in NO3 TF NO3 out mg/l mg/l mg/l < 0,5 20 < 0,5 < 0,5 6,9 < 0,5 < 0,5 < 0,5 17 < 0,5 < 0,5 18 < 0,5 < 0,5 < 0,5 20 < 0,5 < 0,5 17 < 0,5 < 0,5 < 0,5 16 < 0,5 < 0,5 18 < 0,5 < 0,5 < 0,5 < 0,5 < 0,5 22 < 0,5 < 0,5 < 0,5 < 0,5 < 0,5 18 < 0,5 < 0,5 < 0,5 18 < 0,5 < 0,5 16 < 0,5 < 0,5 35 < 0,5 < 0,5 22 < 0,5 < 0,5 29 0,7 < 0,5 < 0,5 28 0,5 < 0,5 38 0,9 < 0,5 32 0,8 0,8 < 0,5 35 1,0 < 0,5 34 0,9 1,2 < 0,5 28 < 0,5 29 1,5 1,3

6,7

6,9

5,9

6,0

55 66

21 26

6,5

5,7

54 50

12 16

49 49

18 18

50

17

23 24

30

1,1 2,2

0,03 0,01

48

11

23 23

34

2,4 2,7

< 0,01 0,01 0,02 0,02

41

7,2

21 21

37

0,7 4,3

47

6,2

15

34

10

34

5,3

12 16

34

9,9 5,2

30

4,4

15 14

30

6,0 7,1

22

3,7

13 11

27

8,0 9,9

17

0,8

9,4 7,9

17

11 13

15

1,5

6,1 5,1

17

10

0,4

4,3 3,8

13 13 13 13 12

5,9 0,01 < 0,01

0,01 0,01 4,1

< 0,01 < 0,01 < 0,01 < 0,01 < 0,01

0,02 < 0,01 < 0,01 < 0,01 < 0,01

< 0,01 < 0,01 < 0,01 0,03 0,02 < 0,01

4,6

4,3

2,4

4,8

4,8

4,0

2,8

< 0,01 < 0,01

2,1

1,6

17 22

2,6

2,1

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

< 0,01

13 13

73

Date

Q outlet l/s 04-05-04 539 04-05-04 05-05-04 17-05-04 831 18-05-04 831 18-05-04 31-05-04 741 01-06-04 870 01-06-04 02-06-04 14-06-04 831 15-06-04 943 17-06-04 23-06-04 28-06-04 89 29-06-04 275 29-06-04 30-06-04 12-07-04 10 13-07-04 99 13-07-04 09-08-04 150 10-08-04 143 10-08-04 23-08-04 312 24-08-04 234 24-08-04 06-09-04 325 07-09-04 190 07-09-04 16-09-04 20-09-04 351 21-09-04 195 21-09-04 22-09-04 04-10-04 138 05-10-04 212 05-10-04 18-10-04 18 19-10-04 169 19-10-04 19-10-04 02-11-04 16-11-04 30-11-04 08-12-04 14-12-04 31-01-05 79 01-02-05 169 01-02-05 14-02-05 139 15-02-05 214 15-02-05 28-03-05 19 29-03-05 106 29-03-05 11-04-05 98 12-04-05 129 12-04-05 13-04-05 25-04-05 237 26-04-05 211 26-04-05 09-05-05 120 10-05-05 126 10-05-05 11-05-05 23-05-05 109 24-05-05 162 24-05-05 13-06-05 60 14-06-05 79 14-06-05

SS in SS TF mg/l mg/l

SS out mg/l

Tot P in Tot P TF mg/l mg/l 1,9 2,8

6

1,7

1,9

47

2,6

0,01 < 0,01

2,4

2,3

0,01 0,01

15

10

0,6

15

0,9

2,2 2,3

17

10 9,7

13

1,1

2,1 1,5

14

9,6 9,8

< 0,01

36

4,3

2,3 2,0

30

9,7 9,9

9,1

5,4

54

7,9

2,2 2,6

44

9,2 8,0

9,2 9,9

6,7 6,7

0,02 0,07 0,01 0,03 0,01

56

12

2,7 2,8

40

7,2 7,2

58

10

3,2 3,5

45

7,5 7,3

69

17

3,7 4,0

47

7,4 7,4

7,2

5,9

< 0,01 < 0,01

6,6

0,02 0,02

13 10

8,6 7,3

0,02 0,02 0,02

12

8,8

0,03 0,01

77

25

3,7 4,0

46

7,3 7,3

13

9,8

0,01 0,01

84

30

4,5 4,5

49

6

7,2 6,9

10 11

< 0,01 < 0,01 < 0,01

86

17

14

17 18

16 16

21

19 18 13 22

18 19

16 16 17 16

16

54

22

11

9,8

13

3

12 11

< 0,01 0,01

20

53

12

2,4

9,4

7,5

< 0,01

< 0,01

68

3,2 2,8

4,0

11

60

+

NH4 out NO3 in NO3 TF NO3 out mg/l mg/l mg/l mg/l 3,9 16 13 3,8 12

6,0

8

44

+

PO4 out NH4 in NH4 TF mg/l mg/l mg/l 10 0,7 < 0,01

0,03 0,01

2,7

25

2

PO4 in PO4 TF mg/l mg/l

< 0,01

9

48

Tot P out mg/l < 0,01 < 0,01

22

18

16

16 17

16 16

24

15

< 0,01 < 0,01 0,01 0,01 0,03 0,02 0,03 0,01 0,03 0,25

0,08 0,20 0,04 0,02 0,03

16

17

0,03 0,08

15

19

< 0,01 0,02

16

17

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

8,1

22

47

9,3 11

92

39

20 22 28

46

10 11

97

39

28 28

47

12 12

95

32

25 30

56

13 11

93

42

34 21

45

11 20

110

66

36 37

36

13 12

110

63

36 22

39

14 25

< 0,01 < 0,01 0,04

16

15 34

16

17

6,9 7,2 7,4

88

0,03

17

6,2 7,2 7,7

< 0,01 < 0,01

< 0,01

35

6,3 16

74

Date

TotN in TotN TF mg/l mg/l 19-05-03 48 20-05-03 46 44 20-05-03 02-06-03 27 29 03-06-03 40 36 03-06-03 16-06-03 30 30 17-06-03 29 27 17-06-03 30-06-03 30 24 01-07-03 32 28 01-07-03 28-07-03 20 29-07-03 28 28 29-07-03 11-08-03 24 12-08-03 20 23 12-08-03 25-08-03 54 32 26-08-03 41 39 26-08-03 08-09-03 68 52 09-09-03 63 44 09-09-03 22-09-03 62 57 23-09-03 73 57 23-09-03 06-10-03 56 61 07-10-03 72 60 07-10-03 20-10-03 61 53 21-10-03 55 52 21-10-03 03-11-03 56 48 04-11-03 56 49 04-11-03 12-11-03 17-11-03 18-11-03 57 49 18-11-03 01-12-03 02-12-03 53 46 02-12-03 03-12-03 15-12-03 16-12-03 47 46 16-12-03 26-01-04 27-01-04 53 41 28-01-04 09-02-04 10-02-04 38 40 10-02-04 23-02-04 24-02-04 35 36 24-02-04 25-02-04 08-03-04 09-03-04 27 33 09-03-04 22-03-04 23-03-04 20 19 23-03-04 24-03-04 05-04-04 06-04-04 18 20 06-04-04 19-04-04 20-04-04 13 14 20-04-04 03-05-04

TotN out COD in COD TF mg/l mg/l mg/l 29 130 67 23 180 75 31 30 120 63 28 180 71 38 40 93 40 34 120 40 43 40 130 50 42 160 55 42 21 59 26 130 48 20 19 76 20 110 35 19 16 190 67 15 190 58 17 12 200 65 15 290 71 13 15 180 58 13 270 83 16 14 150 47 15 240 59 16 11 170 98 14 180 53 17 180 53 19 190 57 24

COD out BOD7 in BOD7 TF mg/l mg/l mg/l 180 26 120 140 120 35 12 200 85 76 25 4 81 78 73 54 80 70 50 10 46 41 26 23 34 25 39 39 32 12 30 28 25 61 12 37 25 25 25 25 27 25 25

BOD7 out TOC in TOC TF mg/l mg/l mg/l 55 17 48 18 50 50 31 14 56 14 50 50 25 10 38 12 48 35 12 52 12 39 21 20 30 12 20 16 22 35 9,6 19 18 58 15 18 64 19 82 21 16 13 56 20 87 23 11 44 15 75 19

25 25

50 56

27 18

50 56

19 19 26

24 27 25 26

73 160 230

41 52

67

20

< 25 < 25

79

17

4

200

48

< 25 < 25

62

16

7,0 7,4 6,5 5,5 7,4 5,5 7,5 5,2 4,9 5,2 4,5 5,9 5,6 4,5

44

11

3,2 3,3

15 24

4 45

10

12,54

7,72

7,67

12,46 12,46

7,75

7,28

12,49 12,66 12,69

7,80

12,51

7,59

12,41 12,42 12,61

7,78

7,77

7,27

12,54 12,65

7,56

7,22

12,72 12,58

8,01

7,33

12,58 12,86 13,04

12,98 7,82

7,45

7,84

7,05

13,05

13,04 7,96

7,21

12,84

7,96

7,36

13,13 13,09

8,09

7,09

13,10

8,22

7,21

13,13 13,15

5,9 4,1

22 22 37

7,62

5,2 4,1 4,5

3,9

140

7,24

4,5 4,8

13

22 22

pH out

5,0 5,0 4,4

74

4

pH TF

7,69

26

33

pH in

7,74

4

40 23 26

TOC out mg/l 22 15 22 20 18 22 24 20 23 22 21 20 11 12 11 8,3 8,2 7,6

5,2

4

13,16 3,4

21 22

36

21 21

23

20 18

20

18 18

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

21

14

8,2

9,7

7,4

8,18

7,69

13,19

7,87

7,69

13,24 13,07

4,0 4,0 2,8 4,0

13,01 7,79

7,27

12,98

7,77

7,74

13,02 12,97

7,95

7,49

13,10 12,99

2,9 2,8 2,9 2,7

75 Date

TotN in TotN TF mg/l mg/l 04-05-04 12 18 04-05-04 05-05-04 17-05-04 18-05-04 13 14 18-05-04 31-05-04 01-06-04 01-06-04 02-06-04 14-06-04 15-06-04 19 19 17-06-04 23-06-04 28-06-04 29-06-04 18 18 29-06-04 30-06-04 12-07-04 13-07-04 41 36 13-07-04 09-08-04 10-08-04 60 54 10-08-04 23-08-04 24-08-04 62 55 24-08-04 06-09-04 07-09-04 65 57 07-09-04 16-09-04 20-09-04 21-09-04 75 66 21-09-04 22-09-04 04-10-04 05-10-04 84 74 05-10-04 18-10-04 94 85 19-10-04 91 80 19-10-04 19-10-04 02-11-04 16-11-04 30-11-04 08-12-04 14-12-04 31-01-05 01-02-05 98 83 01-02-05 14-02-05 15-02-05 100 87 15-02-05 28-03-05 29-03-05 110 88 29-03-05 11-04-05 12-04-05 100 89 12-04-05 13-04-05 25-04-05 26-04-05 100 87 26-04-05 09-05-05 10-05-05 120 110 10-05-05 11-05-05 23-05-05 24-05-05 120 110 24-05-05 13-06-05 14-06-05 14-06-05

TotN out COD in COD TF mg/l mg/l mg/l 17 16

COD out BOD7 in BOD7 TF mg/l mg/l mg/l

BOD7 out TOC in TOC TF mg/l mg/l mg/l 15 7,8

15 14

18

13

11

7,3

2

TOC out mg/l 2,6 6,9

13,10

2,2 4,1

14 12

20

8,2

2,5 3,2

12 12

36

12

2,4 2,5

12 12

53

11 11

74

22

3,1 8,4

11 11

68

20

3,5 3,0

72 75

30 26

5,5 4,1 4,1

97 72

20 14 16

95

15

10 6

12 12

78

12 12

72

14 15 15

15

24

25

24

80 120

29 31

120

9

5

81

9

5 2 3

45 41 49 49

62

18

12,99

7,96

2

120

40

87 110

36 48

5

100

< 25 < 25

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

12,80 12,88

8,07

7,56

8,13

6,79

12,73 12,87

4,7 6,4 4,4 4,4 6,2

8,42

7,89

13,32

8,16

7,66

13,61 12,95

7,81

6,98

13,11 12,83 12,90

7,80

7,36

12,85

8,00

7,35

12,68 12,74 12,86

7,90 50 47 41 51

7,48

12,98

28 38

< 25 < 25 < 25

13,10 12,93

11

94 140

110 160

6,96

11

4,7 6,7 8,5 6,4 5,9 4,1 4,4 4,4

220 370

8,01

3

33

38 41

12,97

13,05 13,11 13,11

99

88 100

7,11

4,2 2,3 4,5

32 39

280 390

8,60

13,00

4,0 3,3

40 40

12,61

3,0 2,1

30

32 32 < 25 < 25 < 25 < 25

7,69

5,0 3,1

100

91 120

7,89

4,6 6,5

31 31

310 420

12,99

2,7

7,5

230 220

pH out

13,04

24

12 12

pH TF

3,2 2,6

14 12

18

pH in

120 6

42

63

7,35

12,52

4,8 4,7

12,44

8,2 6,2

12,53

76

Date 19-05-03 20-05-03 20-05-03 02-06-03 03-06-03 03-06-03 16-06-03 17-06-03 17-06-03 30-06-03 01-07-03 01-07-03 28-07-03 29-07-03 29-07-03 11-08-03 12-08-03 12-08-03 25-08-03 26-08-03 26-08-03 08-09-03 09-09-03 09-09-03 22-09-03 23-09-03 23-09-03 06-10-03 07-10-03 07-10-03 20-10-03 21-10-03 21-10-03 03-11-03 04-11-03 04-11-03 12-11-03 17-11-03 18-11-03 18-11-03 01-12-03 02-12-03 02-12-03 03-12-03 15-12-03 16-12-03 16-12-03 26-01-04 27-01-04 28-01-04 09-02-04 10-02-04 10-02-04 23-02-04 24-02-04 24-02-04 25-02-04 08-03-04 09-03-04 09-03-04 22-03-04 23-03-04 23-03-04 24-03-04 05-04-04 06-04-04 06-04-04 19-04-04 20-04-04 20-04-04 03-05-04

1 2 3 Cond. Cond. Cond.

In TF out

1

2

3

3

3

2

3

2

Mg out mg/l <1

Fe out mg/l 0,024

Al out mg/l <1

Enteroc.

TF

Enterococci out

out pre filter

61000

< 10

241900

4106

< 10

7330

330

2800

240

180

3100 2600

880 850

<1 <1

0,020 0,020

<1 <1

1030 912

280

340

3000 2800

870 790

<1 <1

0,020 0,028

<1 <1

975 793

2900 280

160

850 740

<1 <1

0,020 0,020

<1 <1

931 778

800 730

0,060

<1

260

2900 2300

<1

59,3

59,9

800 765

250

2500 2300

790 680

3000 2100

730

2500

660

1200

69,9

75,1

1110 1080

72

70,1

67

64

840 75,4

140 834

88,7

Alk. out

3 Ca out mg/l 850

86,5

Alk. in Alk. TF

3

E-coli

150

102

94,7

831 780

640

140

2500 2300

640 580

100

94,7

863 742

390

95

2700 2100

650 570

101

84

861 472

380

65

2500 1200

640 700

2300

680

2500

730

879 94,6

330 894

310

51 2600

380

73

2400

860

<1

0,028

<1

790 < 10

68,1

56,8

809

300

51

880

2400

770

2700

770

<1

0,060

<1 11200

220

70

2900

800

3300

810

< 10

< 10

220

100

2100

730

99

2400 2400

790

220

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

5290

3 E-coli Comments out 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample

77 Date 04-05-04 04-05-04 05-05-04 17-05-04 18-05-04 18-05-04 31-05-04 01-06-04 01-06-04 02-06-04 14-06-04 15-06-04 17-06-04 23-06-04 28-06-04 29-06-04 29-06-04 30-06-04 12-07-04 13-07-04 13-07-04 09-08-04 10-08-04 10-08-04 23-08-04 24-08-04 24-08-04 06-09-04 07-09-04 07-09-04 16-09-04 20-09-04 21-09-04 21-09-04 22-09-04 04-10-04 05-10-04 05-10-04 18-10-04 19-10-04 19-10-04 19-10-04 02-11-04 16-11-04 30-11-04 08-12-04 14-12-04 31-01-05 01-02-05 01-02-05 14-02-05 15-02-05 15-02-05 28-03-05 29-03-05 29-03-05 11-04-05 12-04-05 12-04-05 13-04-05 25-04-05 26-04-05 26-04-05 09-05-05 10-05-05 10-05-05 11-05-05 23-05-05 24-05-05 24-05-05 13-06-05 14-06-05 14-06-05

Cond. Cond. Cond.

In TF Out

Alk. in Alk. TF

Alk. out

Ca out mg/l

Mg out mg/l

Fe out mg/l

Al out mg/l

Enteroc.

TF

Enterococci out

E-coli out pre filter

2400 < 10

806

2300

780

<1

0,110

<1 359

< 10

630

< 10

1700

540 < 10

370

30

2000

620

1700

420

2000

530

2100

560

< 10 126

104

688

480

130

745

730

2300

2100 2100

739

1200

144

124

788 581

550

150

64

718

164

146

692 719

682

600

80

1

0,024

1 30

< 10

960

719

< 10

860

19890

< 10

907

669

< 10

960

8400

< 10

7590

690

570 580

<1

0,020

<1

400 550

530

2400 1700

720 500

1

0,031

1

2100

630

1

0,068

1

2100

580

2100

610

1

0,140

1

2000

C:\MAGNHILD\NI\sluttrapportering\Stockholm Vatten\FinalReport from pilot plant in Sweden 18072005 mfø.doc

E-coli Comments out 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 14 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 14 day sample grab sample < 100 grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample grab sample grab sample grab sample < 100 grab sample grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample 2 day sample 12 day sample grab sample < 100 grab sample 2 day sample 14 day sample grab sample grab sample 2 day sample 12 day sample