Inside Mining March 2016 by 3S Media

www.miningne.ws

AFRIC AN UPDATES ON THE

GROUND AND UNDERGROUND

Aveng Water

Leading mine-impacted water treatment

BRAKFONTEIN EXTENSION Doubling down on production

SHONDONI COLLIERY

Mpumalanga mine’s great trek

ISSN 1999-8872 • R50.00 (incl. VAT) • Vol. 09 • No. 03 • March 2016

WATER MANAGEMENT Solutions for backveld miners

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CONTENTS

AFR IC AN UP DATES ON THE G ROUND A ND UNDERG ROUND

MANAGING WATER, MAKING PROFITS A surface-mount, vertical turbine pump from Xylem. Read more about pump optimisation on page 14

MARCH

32 EDITOR’S COMMENT

PIPES, PUMPS & VALVES

Sometimes, less is more

COVER STORY

Pre-engineered water-saving solutions

24 Pumping emulsions as

2016

ON THE COVER p4 www.miningne.ws ws

alternative explosives

4 Aveng Water – leading mine-impacted

A F R I C A N UP DATES ON THE

water treatment

AFRICA ROUND-UP 7

News from around the continent

ECONOMICS, FINANCE & RISK 8

Positive forecast for coal

COMMODITY: COAL 10

Brakfontein doubles down

Shondoni's big move

A comparison of mill liners

Energy efficiency in comminution

MATERIALS HANDLING 35

Avoiding failures

Aveng Water

Leading mine-impacted water treatment

COMPANY NEWS 37

Streamlining operational efficiencies

Going local improves competitiveness

EVENTS

WATER MANAGEMENT

Progress in the mining industry

African Mining Indaba round-up

Managing water, making profits

G ROUND A ND UNDERGROUND

COMMINUTION

BRAKFONTEIN EXTENSION

Doubling production figures

SHONDONI COLLIERY

Moving into the new mine

WATER SAVING

Pre-engineered solutions

ISSN 1999-8872 • R50.00 (incl. VAT) • Vol. 09 • No. 03 • March 2016

For more than a decade now, Aveng Water has assisted mining companies in establishing cost-effective solutions for treating mineimpacted water

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EDITOR'S COMMENT

Publisher Elizabeth Shorten Editor Mientjie Kleinhans Assistant editor Mpinane Senkhane Head of design Beren Bauermeister Designer Ramon Chinian Chief sub-editor Tristan Snijders

Sometimes, less is more

Sub-editor Morgan Carter Contributors Xavier Prost, Tony Stone Client services & production manager Antois-Leigh Botma Production coordinator Jacqueline Modise Marketing & digital manager Philip Rosenberg Financial manager Andrew Lobban Administration Tonya Hebenton Distribution manager Nomsa Masina Distribution coordinator Asha Pursotham Printers United Litho Johannesburg Tel: +27 (0)11 402 0571 ___________________________________ Advertising Sales

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This axiom was quite true for this year’s African Mining Indaba – wider rows between the exhibiting stalls, and fewer exhibitors and people. Although the attendance was toned down, some exhibitors felt very positive about the people they met.

to resolve certain issues. Highlights of this discussion are available on page 39. While a big focus was on the Mining Indaba, with great launches and discussions, part of South Africa was absorbed by the news of the collapse at the Lily Mine in Barberton, Mpumalanga. This is one of those disasters that will be remembered for some

time to come. As a direct result of this incident, the DMR wants to meet with

S EXPECTED, MANY conver-

CEOs of mining companies to discuss

sations took place at the

health and safety issues.

African Mining Indaba, both in conferences and in the

What was quite ironic about the Lily Mine disaster is that the incident

exhibitors’ hall. Sandra du Toit, head:

occurred a few days after Minister

Annual subscription:

Mining and Metal, Standard Bank, not-

Mosebenzi Zwane, DMR, announced

South Africa: R550.00

ed that she heard CEOs of companies

the mine safety statistics of 2015. The

(incl VAT & postage)

talking about 2016 being a harsh and

figure of 77 fatalities was the lowest

African countries: US$80

difficult year for the mining industry. Yet,

in South Africa since 1994, which

Foreign: US$100

some exhibitors spoke positively about

clearly indicates that mining compa-

Email: subs@3smedia.co.za

the people they met.

nies have been committed to high

ISSN 1999-8872 Inside Mining Copyright 2016. All rights reserved. ___________________________________ All material in Inside Mining is copyright protected and may not be reproduced either in whole or in part without the prior written permission of the publisher. The views of contributors do not necessarily reflect those of the publishers.

To our avid readers, be sure to sign up and get the latest updates and inside scoops from the mining industry. Check out what we are talking about on our website and Facebook page, or follow us on Twitter and have your say.

Does this mean that, although there were fewer delegates than the previous

safety standards. In the interim, Angola found its largest

year, those who attended the African

diamond so far – over 404 carats – at

Mining Indaba were there to do serious

Lucapa Diamond Company’s Lulo Di-

business? I guess time will tell. What I

amond Project. The white diamond is

do know is that various discussions took

a type 2a D-colour and is estimated to

place at the African Mining Indaba

be worth $20 million. Still in the southern

and, with a tough year ahead, industry

region of Africa, and still on the subject

relationships were formed and strength-

of diamonds, Botswana’s 1 111 carat

ened. One such organisation formed at

diamond was finally named, after a

the Indaba was the Africa Mining Vision

competition was held for Botswana’s

(AMV) compact between African gov-

citizens. The winner, Thembani Moitl-

ernments and mining companies.

hobogi, named the diamond “Lesedi

Read more about this coalition in the

La Rona”, which means “our light” in

African Mining Indaba section of this edi-

Setswana. The beginning of February

tion. We also heard the deputy minister

also saw Shondoni Mine’s big move.

of the Department of Mineral Resources

This Sasol mine project started in 2012

(DMR), Godfrey Oliphant, speaking at

and will be finalised in 2017. Read more

the Canadian Interactive Breakfast

about the move on page 12.

Forum. He explained that the DMR un@mining_news www.facebook.com/pages/ Mining-News

derstands the challenges facing mining companies and how the department is committing to working with stakeholders

Mientjie Kleinhans IN SID E M IN IN G 0 3 | 2016

COVER STORY

Mine-impacted water treatment South Africa is facing a daunting task in rectifying the legacy of long-standing mine water seepage into worked-out mining areas. The contact of this ingress water with the freshly exposed rock creates water with a high concentration of dissolved salts and, in some cases, heavy metals.

HE NOW POLLUTED water, or

converts more than 60 Mℓ/day of MIW to

small amounts remain in the wastewater.

mine-impacted water (MIW), is

water that exceeds both environmental

From a financial perspective, it is possible

a major issue, as discharge into

discharge and SANS Class 1 drinking

to establish a large, regional water recla-

the surrounding environment

water standards. South Africa’s mining

mation plant that services local mines on

results in pollution of our natural water

majors have demonstrated their com-

a toll water treatment basis. This would

sources. The management of this MIW

mitment to environmental sustainability

enable the junior miners to take advan-

requires sophisticated and diverse ac-

and the people of the Mpumalanga

tage of the economy of scale of large

tions ranging from reducing ingress to

coal mining region through investment in

plants to treat their MIW.

treating the water prior to discharge into

these large and capital-intensive water

the environment.

reclamation plants.

er, Aveng Water, says that mining

Such large investment in water recla-

companies need to be much more

treatment as part of the holistic mining

mation plants is not within the means of

proactive and creative in their ap-

approach rather than merely a compli-

the many junior miners in the industry,

proach to meeting environmental

ance issue is critical to the sustainability

although the need for water treatment

compliance obligations.

of mining in South Africa. Fortunately,

on these mines is just as dire. This is where

“Mines need to realise the opportuni-

integrated solutions are available from

Aveng Water and the Aveng group can

ties to exploit value within their immedi-

specialised water treatment companies.

assist with creative technical and finan-

ate environment, through the opportu-

cial solutions. There are technical ways

nity to recover valuable minerals from

technology and project delivery compa-

of offsetting some of the operating costs

wastewater, or to sell the treated water

ny in the Aveng Africa stable, a leading

of water treatment.

to an industrial partner such as a power

Changing mindsets to view water

Aveng Water is a water treatment

South African infrastructure develop-

For example, Aveng Water’s process

station, or to cooperate with neighbours

ment firm. Aveng Water has assisted min-

technology applications can assist min-

to gain economies of scale. Such strat-

ing companies in finding cost-effective

ing companies by treating water while

egies regarding treatment of their MIW

solutions for treating MIW for more than

simultaneously recovering some valua-

can impact positively on the investment

a decade. Aveng’s proven HiPRO tech-

ble components. This may be the water

profiles of the companies, and the at-

nology is implemented in three large-

itself, a reagent such as acid, or valu-

titude of local residents and regulators

scale water reclamation plants and

able minerals from the mine, of which

towards the mines.”

The Optimum water reclamation plant has Blue Drop status

Suzie Nkambule, general manag-

INS IDE MI NI NG 0 3 | 2 0 1 6

COVER STORY

The eMalahleni water reclamation plant provides water to eMalahleni Municipality produce treated water that meets and

MIW as a resource?

exceeds SANS potable water standards.

He recommends mines to consider

Linington explains that the Optimum water

drawing water from an internal source,

reclamation plant has Blue Drop status

targeting complete water re-

“We offer turnkey solutions for clients. We

and provides water to Hendrina Municipal-

use for off-grid sustainability

design, build, operate and maintain the

ity and the eMalahleni water reclamation

and finding opportunities

entire facility for the client. We provide

plant provides water to eMalahleni Mu-

to sell treated water

advice on a consultancy basis to clients

nicipality. The MIW of the Mpumalanga

or recover valuable

for a tailor-made solution that considers

coal fields is characterised by high levels

minerals or by-prod-

the client’s overall situation and not just

of sulfate, calcium, magnesium, sodium

ucts to offset some

capacity and quality of the MIW to be

and heavy metals. The HiPRO process is

of the cost of treating

treated,” says Nkambule.

a three-stage process based on calcium

MIW. “The water, often

“Our company has done over a dec-

chemistry and ultrafiltration (UF) and re-

for process reuse, doesn’t

ade’s worth of research in the acid mine

verse osmosis (RO) technology. The first

have to be treated to the same environ-

drainage space to understand the compli-

stage entails neutralisation or softening,

mental standards as discharge water.

The Optimum water reclamation plant provides water to Hendrina Municipality

Professional assistance

cations in terms of the chemistry for treating acid mine water,” says Andrew Linington, executive, Aveng Water. He adds that the company has more experience in treating mine water than any other, which places Aveng as the leader in the treatment of MIW. Nkambule says that it is essential for mines to get the right service provider to manage the environmental compliance standards for water treatment and water reuse and/or discharge. “This is where companies like ours are very important. There is no single, guaranteed pre-en-

“Our company has done over a decade’s worth of research in the acid mine drainage space to understand the complications in terms of the chemistry for treating acid mine water.” Andrew Linington,

One needs to do an assessment of what the environmental requirements are by asking questions and tailoring an appropriate solution,” says Linington. “From a financial perspective, mining companies need to look around at options to procure services. These companies need specialists to help them, ideally at an early stage – preferably at mine planning. Most mining companies in South Africa are yet to go ‘above and beyond’ to solve the MIW issue,” says Nkambule. Linington says

executive, Aveng Water

that MIW may require management and

ent on feedwater quality and presents

with calcium hydroxide, followed by clar-

until the exposed rock is weathered to a

unique process engineering requirements.

ification, UF and RO separation of salts

degree that does not result in the con-

We focus on early-stage engagement to

from water. The concentrated brine from

tamination of ingress water.

give mines the assistance they need,”

the first stage is treated in a gypsum desat-

says Nkambule.

uration reactor in the second stage. The

ment is going to require an active solu-

desaturated water passes through a clari-

tion. Ours is an active process in which

fication stage, UF and RO separation. The

we use chemicals and/or electricity to

The company has designed, built and

third stage is similar to the second. This pro-

treat water; in the longer term, a passive

now operates – under contract – three

cess results in best-in-class feedwater re-

solution such as biological treatment will

mine water treatment plants that treat in

covery of up to 99%, resulting in the need

be required to reduce treatment costs,”

excess of 60 000 m3/day of MIW. The plants

for only a small brine treatment plant to

concludes Linington. Aveng Water pro-

meet zero liquid discharge requirements.

vides technical solutions to treat and

gineered solution to mine water treatment, as plant process performance is depend-

Experience

The waste from the process is heavy

treatment for possibly the next 100 years,

“For the next 20 to 30 years, water treat-

manage MIW that, if not treated, would

metal sludge from the first stage, gypsum

negatively impact surrounding environ-

by-product and gypsum/magnesium

ments and mines’ permits to operate. Its

hydroxide sludge by-product from the sec-

solutions are based on the HiPRO pro-

ond stage and monovalent and gypsum

cess, which is customised for each mine’s

sludge from the third.

requirements, whether for small, mobile

The product water can be released into

units or large, permanent plants.

the environment or remineralised for potable water. “These flagship water reclamation plants have received several industry awards, including the coveted Blue Drop status and prove our company’s expertise in treating mine water for reuse at affordable cost,” says Linington.

www.aveng.co.za

IN SID E M IN IN G 0 3 1 | 2016

MINING NEWS

from around the continent

Ghana

to mineral beneficiation” in Zimba-

AngloGold not yet looking for JV partner in Ghana

bwe. “Capital constraints, electricity constraints, high cost of power, low

Africa’s top gold producer, AngloGold

feedstock and low commodity prices

Ashanti, said, at the Investing in African

are affecting mineral beneficiation,”

Mining Indaba that it would not look for

according to the report. It said that only about 25% of Zim-

a new joint venture partner for its Obuasi mine in Ghana until it had an investment agreement with the government.

Zambian government spokesperson Chishimba Kambwili

AngloGold Ashanti improved its 2014

babwean gold miners have plans to undertake exploration. The grade of underground gold being mined in the

production outlook partly due to the

approved the proposed tax measures,

transition of the Obuasi mine to limited

which are aimed at sustaining opera-

country has also declined, it said. Zimbabwe currently produces about

operating state by the year end. Anglo-

tions in the mining industry, securing jobs

20 tonnes of gold per year. About

Gold says a new Obuasi mine partner

for citizens as well as collecting more

54% of miners in the country are

will require an investment deal with the

tax revenue in times of relatively high

large-scale, while the remainder are

Ghana government. Randgold Resources,

copper prices,” government spokes-

artisanal and small-scale gold miners.

in December 2014, pulled out of a joint venture with AngloGold to redevelop Obuasi, a decision that could

man Chishimba Kambwili said in a

“Some 75% of the gold miners in Zim-

statement. The cabinet also

babwe are doing underground mining

approved the suspension

while 25% are undertaking surface min-

of the 10% export duty on

ing. Mining companies are undertaking

spell closure for one

ores and concentrates, for

labour rationalisation and mine-to-mill

of Ghana’s most im-

which there are no pro-

optimisation to manage rising costs,”

portant mines. “With

cessing facilities in Zambia,

said the report. A confidence index

regards to Obuasi,

and the removal of the

of the mining business in the country

we are firmly of the view that we must now progress our discussion with the Ghanian government to

variable profit tax on income from mining operations. The government will maintain the corporate income tax for mining

found mining investors in the country are also concerned about political and regulatory issues.

obtain all the regulatory approvals neces-

companies at 30% while a flat mineral

Unfruitful wage talks

sary to conclude a satisfactory investment

royalty rate of 6% would be introduced

The Zimbabwean Chamber of Mines

agreement,” AngloGold chief executive

for precious metals and gems, Kambwili

is engaging with worker unions in the

Srinivasan Venkatakrishnan said at the

said. For minerals and base metals other

country over wage negotiations. Tina-

mining conference.

than copper, royalties will be fixed at 5%.

go Ruzive, president of the Associated

“Only then will we restart the search for a joint venture partner,” he added.

ZIMBABWE

at the mine in the central Ashanti region

Zim miners commit US$362 million to beneficiation

in 2014 and depressed bullion prices have

Zimbabwean mining companies have

left questions about the mine’s viability.

invested up to $362 million in mineral

AngloGold laid off thousands of workers

ZAMBIA

Price-based royalties for copper mines Zambia’s cabinet has approved a new royalty system that varies depending on

country’s main mining union – said that the chamber and the union have since held two meetings, which have yielded no progress. He said workers need to be more mo-

beneficiation projects expected to be

tivated and incentivised to be truly pro-

completed in the next five years, as the

ductive. But, with most mines rationalis-

government intensifies a value-addition

ing costs, it is unlikely that Zimbabwean

drive to create more employment and

mine workers will be awarded significant

keep money in the country.

wage increases.

Zimplats, owned by Impala Platinum,

the copper price, as Africa’s second big-

as well as Unki mine, controlled by

gest producer seeks to keep struggling

Anglo American Platinum, are some

mines open and limit job losses, govern-

of the companies that have already

ment said in February.

made provision for smelter projects in

Mining companies operating in Zambia,

Mine Workers’ Union of Zimbabwe – the

Mining in Zimbabwe remains a thorny issue

the country. A state of mining report by

including Vedanta Resources and Glen-

the Zimbabwean Chamber of Mines

core, have cut thousands of jobs and

has now said that about 60% of the

closed copper shafts in recent months

country’s mining companies have in-

with prices near six-year lows. Mining lob-

vested in value-addition projects across

bies had asked for a price-based royalty

mineral categories such as diamonds,

structure to ease the tax burden during

gold, platinum and nickel. However, the

a period of depressed prices. “Cabinet

survey found that “there are challenges

IN SID E M IN IN G 0 3 | 2016

ECONOMICS, FINANCE & RISK

Positive forecast for coal Reviewing an article I wrote on coal some months ago, in light of the events of the past year in South Africa and abroad, it is clear that the woes experienced by the industry in the last four years have increased. By Xavier Prost

HAT ARE WE to expect

opposite – less production and fewer

once all-powerful, ever-present coal

for 2016? Probably a

exports – to be able to balance supply

mayors, with some small exceptions,

leaner, tougher industry,

and demand. Colombia has devel-

have almost entirely disappeared from

designed to accept the

oped as a formidable foe to South Af-

the limelight. Juniors or BEEs, which

challenges imposed by smaller profit

rican coal, as it first took our European

once were present at such events in

margins, lower seaborne prices and

market, and now it threatens to snap

great numbers, have now dwindled to

legislation that, if implemented, will im-

up the Indian market – presently our

a very small number. Mainly traders,

pact negatively on current and future

biggest client in the Far East. Colombi-

buyers and shippers attended. Some of

coal mines.

an coal is priced very competitively in

the Far East and the Middle East coun-

that market, while South African supply

tries still need steam coal. Also, South

is hampered by abnormal price in-

Africa is developing an African market,

Last year, I highlighted the role of China in the disastrous market situation.

creases caused by market responses to

once very small, which grows by the

South African coal has not been ex-

what some analysts call manipulations

year. We could, and will likely, increase

ported to China for almost two years.

from a buyer seeking to decrease our

tonnages to these areas in the future.

Presently, the greater enemies of coal

market availability.

This year, China is just a memory, as

are the Paris COP conference and the

After attending the famous McClos-

Since our exports need to decrease, given that markets are oversupplied

oversupply created by exporters eager

key Coal Export Conference in Cape

and we have less exportable coal, at

to grow, like Colombia and Austral-

Town, in early February, I perceive

the current prices, South Africa does

ia, in conditions that require just the

great changes in the industry. The

not need more port and rail capacity.

INS I DE MI N I N G 0 3 | 2 0 1 6

ECONOMICS, FINANCE & RISK Most lower-quality coals can be sold in the local market, maybe at better prices than exports

of China’s domestic industry and rising Indian supply diminishes any chance of a price recovery.”Most of our exports – around 47% – are set to go to India in 2017, but for how long?

South African inland market Since our export markets are dwindling

To build it now could be a waste of

and prices, according to forecast,

resources. If there is some capital to

are continuously decreasing, what

be invested, it would be best used for

can the industry in South Africa do to

rail, to more efficiently move coal from

survive? I believe the most important

mines to local users (Eskom and others)

thing is to decrease exports in order to

and to build inland coal handling facil-

increase, even slightly, demand, which

ities. An inland port could facilitate the

will result in a rise in prices. Most of the

logistics of the producers and users.

lower-quality coals can be sold in the

A question that has been asked

local market, maybe at better prices

about this idea of developing a strong-

than exports. Also, the better-quality,

er, more viable, local coal market is:

6 000 kcal/kg coals could find users in

why promote the local market and

the local market, if only they could be

why now? The answer is that the indus-

screened and sized.

try – i.e. producing mines – needs to sell to survive. For the most part, exporting it is not

One thing is for sure: with the ongoing energy crisis in South Africa, coal prices in the inland market cannot

producing enough revenue to justify

decrease – in fact, they will probably

expenditure; on the other hand, with

increase soon.

the developments in energy supply, I believe the current inland market

What's next for coal?

coal sources need to be increased,

While competition heightens and vari-

in grades and tonnages. With the ad-

ous constraints hinder coal prices and

vent of the IPPs (independent power

coal power expansions, it is widely

producers), there is going to be an

agreed that coal is set to stay in the

increased need of thermal coal usage

energy mix for a long time to come

– even if Eskom decreases coal burn.

because there is no alternative solution

Coal demand Quoting a recent press release from Platts, “The failure by Indonesian ther-

that can provide reasonably priced electricity and no solid replacement for steel making. The future for coal seems to lie mainly

mal coal producers to indicate any

in Asia. The outlook indicates that Pa-

significant cut in production for 2016

cific demand will continue to increase

makes it unlikely that prices will recov-

and Atlantic demand is set to continu-

er in the near term, as demand in the

ally decline as result of weak demand

main coal consuming countries contin-

– not a shortage in supply. The condi-

ues to be low. The thermal coal market

tions that determine coal’s market po-

remains victim to weaker demand from

sition are continuing to be increasingly

key importers. The continued support

tougher. Coal’s light is still burning.

FIGURE 1 globalCOAL weekly indices

IN SID E M IN IN G 0 3 | 2016

COMMODITY: COAL

Doubling down on production

Doubled production figures and an extended life of mine were two of the reasons to extend the Brakfontein Colliery. The new extension and the new crushing and screening plant investment of R10 million will result in the production of about 300 000 tonnes a month. By Mientjie Kleinhans

RAKFONTEIN EXTENSION is

to 180 000 tonnes a month are expect-

Operations

located across the road from

ed to double once the new extension is

Each mine operates a fleet of three

Brakfontein coal project,

fully operational. Jacques Roux, general

excavators, 13 articulated dump

about 20 km from Delmas,

manager, Brakfontein, says that they

trucks of between 40 and 45 tonnes, a

Mpumalanga. The new extension has

will apply the lessons they have learned

grader and a dozer, in typical box-cut

opened up the box cut and is currently

from Brakfontein over the period of op-

mining methods.

finalising its infrastructure of offices and

eration at the new extension. “The new

workshops. The new extension will add

extension is almost a duplicate of the

seam and mainly supplies thermal coal

between seven and ten years’ worth

original mine, in terms of the size of the

to Majuba Power Station. Extension will

of life to the mine’s current remaining

operation, fleet and staff. It is almost a

hopefully also supply Eskom with coal,

expected lifespan of between five and

copy-and-paste scenario and, there-

once all the necessary procedures

seven years. Furthermore, the current

fore, we will apply all our experience

are in place and a contract has been

production figures of between 150 000

and skills where possible.”

awarded accordingly.

Brakfontein mines the lower fourth

The new crushing and screening plant at Brakfontein

INS I DE MI N I N G 0 3 1 | 2016

COMMODITY: COAL Crushing and screening plant

candidates to a training facility to be

The operations initially started with two

trained on big yellow machines. We will

small, mobile crushers, which were able

employ those people at the first avail-

to deal with 100 to 150 tonnes an hour.

able opportunity as trainee operators,”

Last year, the mine invested in a crush-

he states.

ing and screening plant, to the value

Roux explains that there is a huge

of R10 million, and can now handle

supply of general workers from the Del-

about 500 tonnes an hour. “The plant

mas community, but a small supply of

has been running for 24 hours a day,

skilled workers. “We need people with

seven days a week. So far, so good,”

certain basic qualifications just to start

says Roux. The plant consists of a jaw

on the mine’s operations, and that is

and drum crusher. “The jaw crusher has

why we invest in knowledge training.”

a built-in screen that removes the -50 material from the circuit and includes it

Rehabilitation

again just before the slewing conveyor,

The mine will be backfilled as opera-

as it is then the ideal size for the stock-

tions continue, until it has reached its

piles,” explains Roux.

end of life. “Once we are done mining

Lessons learned

at Brakfontein, management will decide whether the land will be sold, or

“The main lesson that we learned is

reapplied in a different manner. As this

to screen more than we crush. If frag-

is mostly agricultural area, it will make

mentation is done correctly, half of

sense to use the land accordingly, but

the material will be the ideal size. This

we are not in the agricultural business,

results in a huge energy saving and less

yet,” laughs Roux. Extension will be re-

dust – something we learned from this

habilitated in the same manner.

plant,” says Roux.

Uniqueness

“The main lesson that we learned is to screen more than we crush. Correct and accurate fragmentation results in a huge energy saving and less dust.”

Future The future of Brakfontein’s operations

There are three aspects that make

relies mostly on Extension, which has

Brakfontein coal mine unique, ac-

about 7 to 10 years left. Management

cording to Roux. About 80% of the

will apply its experience and the les-

workforce at Brakfontein resides in the

sons learned from Brakfontein to Ex-

local community, Delmas. “This can be

tension to ensure ultimate results. The

both beneficial and detrimental to the

management team believes in visible

mine. The moment that the people are

veld leadership and, therefore, Roux

unable to leave the area for whatever

spends most of his time in the mine,

reason, to get to the mine, the mine’s

together with Satish Mudalliar, general

plant, similar to the new installation at

operations are in trouble, as most work-

manager: Operations.

Brakfontein, is planned for Extension in

ers are unable to attend work. The rel-

According to them, being visible at

The lower fourth seam mined at Brakfontein

the near future. “Other than that, we

atively young workforce is also unique

operations level is part of the mine’s

will continue to backfill as we mine the

to Brakfontein.

success story. In addition, a processing

pits,” concludes Roux.

“Initially, there was no minimum requirement in terms of years’ experience. We had the scenario where a big portion of the local community was qualified with no experience – a real catch-22 situation. We wanted to be an active supporter of the local community,” explains Roux. He reckons that the third claim to uniqueness is the number of female employees that work in the mine. “About 30% of the operators are females and we will duplicate that at Extension as well,” says Roux. “Furthermore, we continually identify novices from the community to train, so that they too can be employable. We are about to send the first six

Preparing the next area for blasting

IN SID E M IN IN G 0 3 | 2016

COMMODITY: COAL

Shondoni’s big move At the beginning of February, the newly constructed Shondoni Colliery replacement mine was ready for the big move of people and equipment from Middelbult mine. Mientjie Kleinhans visited the site just before the move took place.

project is complete. The outstanding

drives. Four of the drives are situated at

work includes the overland materials

the head end and one at the tail end.

handling system, the underground in-

The three-and-a-half-year contract

cline shaft sinking, and the underground

should be finalised in August 2016.

bunker and substation,” says Marius

“Special design work had to go into

Kruger, programme manager: Shondoni

the planning of the conveyor system,

Project, Sasol Mining.

as it had to pass several slimes dams,

Shondoni mine is a replacement mine

roads and informal settlements. It also

for Middelbult Colliery, and has been

had to cross a stream, road and flood

established to deliver 9.2 Mtpa, that can

plain with an 800 m fully enclosed gan-

be expanded to 10.5 Mtpa, with the as-

try structure, which has to be fully en-

sociated infrastructure for six production

closed for environmental requirements,”

and two stonework sections. The new

explains Kruger.

facility will include maintenance facilities

for a total of ten production and four

Three new shafts

stonework sections.

Three shafts were also included in the

LTHOUGH THE final construc-

project: a ventilation shaft, a man and

tion of the new mine will only

Overland conveyor

be complete in July 2017, the

The new facility will also include a ma-

man and material shaft is 150 m deep

surface infrastructure were

material shaft, and a decline shaft. The

terials handling system from the mine to

and has a 65 tonne payload capacity.

ready at the beginning of February 2016

Sasol Coal Supply by means of a 21 km

“This shaft is specifically sized for the

for three production sections . The pro-

single-flight, overland conveyor without

ject manager expect that the first coal

an intermediate booster drive – the long-

supplied via the overland system from

est in Africa. The conveyor belt consists

Shondoni to Sasol Coal Supply will take

of five horizontal curves in a C shape, is

place in August 2016.

designed for 2 400 t/h, and has an op-

In the meanwhile, people and equip-

erating capacity of 2 000 t/h. The belt

ment will be moved into the offices,

is 1 200 mm wide and travels at 6.5 m/s.

workshops and warehouses on the mine.

It has the capability to work at 80% to

“The mine is operational and 84% of the

100% variable speed with five 1 000 kW

1 2

INS I DE MI N I N G 0 3 | 2 0 1 6

COMMODITY: COAL

SHONDONI FACTS:

• S hondoni is a Venda name that means “place of wealth” • Shondoni has the longest singleflight, overland conveyor in Africa at 21 km • At most, there were 2 400 people simultaneously on-site • More than 2.9 million cubic metres of earth was moved • Over 70 km of electrical cabling has been purchased • Over 44 km of electrical sleeves were installed

• water supply and handling

T he conveyor belt ascending to the bunker from the underground operations

ne of the constructed dams at O Shondoni, with Sasol Synfuels clearly visible in the background

warehouse at Shondoni that is A ready for occupation

T he bunker in its final phase of construction

The new ventilation fans

Inside the boiler room

• shaft roads • diesel and fuel systems.

Project costs “The original budget, which included feasibility and construction costs, was R5.46 billion. So far, R4.52 billion has been committed and R3.77 billion expended. The estimated completion cost is about R5.06 billion – a projected saving of more than R400 million. At Sasol, we drive hard to save where we can in

order to fund other areas that are under-budgeted – that is our strategy for biggest equipment that will go down the shaft, hence the high capacity,”

the project,” says Kruger.

says Kruger. The ventilation shaft is 120 m

Energy efficiency and innovation

deep, and extracts 1 050 m3/s of air with

Careful consideration was given to min-

three 750 kW fans. The incline shaft is

imise the impact on the environment,

6 m x 3 m in size at 12 degrees. It will host

one of the main drives was to focus

one 1 800 mm incline conveyor that will

on green buildings, where practically

operate at 3 200 t/h, even though it was

possible. To start off with, heat pumps

designed at a 3 600 t/h capacity. This

feed water to boilers that have no heat

shaft will be ready in July 2016.

elements. These pumps are “electrici-

Water reticulation systems, which

ty-friendly” as they don’t consume as

include potable water, service water,

much electricity. As the pumps cause

stormwater and fire water, were part of

continuous flow of hot water, there is

the project scope as well as sewer and

water saving as well.

waste management systems. HT and LT

Some solar geysers were installed

electrical power supply and distribution

where heat pumps could not be used,

systems, with an 11 kV substation, were

and movement sensors were installed

constructed to feed power to Shondoni.

in the buildings to switch lights off auto-

As part of the surface infrastructure,

matically when there is no movement.

electronic and data systems were also

“Other initiatives to reduce electricity

constructed. These systems include con-

consumption include the use of ceiling

trol, communication, instrumentation

insulation to keep the temperature con-

and information management systems

stant in the buildings, and the installation

– all in line with the latest technology,

of skylights for maximum use of natural

where possible. These will be implement-

light,” says Kruger.

ed underground and above ground in

Another area where innovative think-

the new buildings, which include ware-

ing was necessary was the winder house.

houses, workshops, offices and change

Due to its huge size, the winder house

houses. The underground infrastructure

was constructed on the surface and

that had to be constructed for 1 km

then lifted with one lift into position. Not

around the service shaft include:

only was this more cost-effective, but it

• two trunk conveyors • workshop facilities

proved to be safer as well. After construction, the 291 tonne wind-

• substations

er house was moved horizontally over

• power distribution

a distance of 58 m and was lifted 30 m high in one day. The same thinking went

“Special design work had to go into the planning of the conveyor system, as it had to pass several slimes dams, roads and informal settlements.”

into the construction of the 15 000 tonne bunker. Precast panels were constructed on the surface and lifted into place with cranes to reduce the exposure of many

Shondoni, and how to redeploy the

people working at heights.

iThemba Lethu shaft,” concludes Kru-

Future plans

ger. He explains that they would also like to have another facility operational

“We are currently busy with a prefea-

by 2022, for four production sections,

sibility study to see how we can mine

apart from the current six production

the extended reserves adjacent to

sections at Shondoni.

IN SID E M IN IN G 0 3 | 2016

WATER MANAGEMENT

Managing water, making profits N Profits can be maximised by applying rigour to pumping system optimisation and water management on mining operations. However, not all mines have adopted this method, yet. By Mpinane Senkhane

ATE MAGUIRE director: Amer-

industry to identify and address every

icas Business Unit, Applied

possible challenge preventing optimal

Water Systems, Xylem, wrote

production. In a journal article, titled ‘A

a white paper, titled ‘Shoring

critical evaluation of the water reticula-

up mine water management’. In the

tion system at Vlaklaagte Shaft, Goede-

paper, Maguire states “a period of soft

hoop Colliery’, by R Lombard, the author

commodity prices may not be the time

looks at challenges at the titular shaft.

to make huge investments in new mine

Increases in water-related downtime had

properties or to expand existing oper-

been identified as one of the bottlenecks

ations, but it can be an excellent time

at the shaft – with the downtime as high

for smaller, quick-return investments that

as 501 hours in 2013, which led to a po-

boost efficiency, reduce costs, enhance

tential profit loss of approximately R12.9

profit margins and prepare an operation

million. Following an investigation, it was

to thrive in better times”. Difficult eco-

discovered that the main causes of the

nomic conditions have forced the mining

water-related downtime were low water

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WATER MANAGEMENT To avoid pump complications in operations, the aim should be to enable pumps to operate more closely to their best-efficiency point across a range of operating conditions

tions is pumps operating outside their op-

assets, ” he continues. At Vlaklaagte, the

timum range, which wastes energy and

main causes of water-related downtime

subjects them to faster wear and shorter

included pipe leakages and bursts; age-

service life. “Pumps in mines are often

ing infrastructure and increased pump

misapplied and, with each pump sold,

pressures also played significant contribu-

manufacturers provide a pump perfor-

tory factors. To remediate this, the water

mance curve that plots the head (in feet

reticulation system was reviewed and an

or meters) against the flow (litres per min-

underground pipe layout was drawn up

ute). Each pump’s curve has a best efficiency point (BEP),” Maguire explains. Essentially, to avoid pump complications in operations, the aim should be to enable pumps to oper-

pressure and low water flow caused by

ate more closely to their BEP

pipe leakages and bursts. “The main root

across a broad range of op-

cause for the low water flow and pressure

erating conditions. Prime can-

was identified as being the low pressure

didates are pumps that move

resistance (1 600 kPa) of the thin-walled

large volumes of water over

galvanised steel pipes used in the under-

long distances or to much

ground inbye water reticulation system,”

higher elevations, notably

Lombard writes.

dewatering and tailings pond

Xylem pump plan on mining operations

decanting pumps. “Where

Pumping system audits

pumps are not operating at or near their

for the shaft after on-site investigations.

Maguire writes that a critical step towards

BEP, replacement may be warranted,”

At Vlaklaagte, water was pumped over

improved water management is to per-

Maguire writes.

very large distances, which meant that

form a pumping system audit. “Such an

major pipe friction losses needed to be

audit will identify waste and operating

Changing compatibility

risks, and can form the basis for a pro-

Maguire identifies that, over time, some

gramme that optimises pumping efficien-

pumps are no longer compatible with the

cy at a high rate of return on investment,”

water’s physical or chemical properties,

pressure had changed. “The pressure

he says. In mines, it’s common to find

which poses the risk of premature failure,

that is required at the CM has changed

ageing machinery in need of repair or

causing costly, unplanned downtime.

over the past years. Previously, the CM

replacement, equipment no longer sized

“Without a strategic plan and mainte-

required only 1 000 kPa of pressure to

properly for required demand – as at the

nance programme for pumping systems,

operate. Pipes were selected accord-

Vlaklaagte shaft – and systems not per-

a mine can find itself with a patchwork

ing to this pressure requirement, and

forming optimally because the operation

of equipment that has not kept pace

thin-wall, galvanised pipes, which can

has changed or evolved.

with project growth and evolution, which,

withstand only 1 600 kPa, were chosen,”

therefore, increases the risk of downtime,”

Lombard writes.

Investing in adequate pumping and

overcome. Water and the pumping of it played a large role in the operations. It was found that the required pump

water management systems is a neces-

notes Maguire. Critical to avoiding a

sary method mines should look at in a bid

scenario of this nature is to “maximise

the first line of defence is the effective

to lower operating costs, enhance perfor-

profits by applying the same rigour to

monitoring and maintenance of equip-

mance and reduce unnecessary, expen-

pumping system optimisation as to mining

ment from installation onwards. However,

sive downtime. The common problem

machinery, mine haul trucks, processing

where this is not possible, or has not

associated with pumps in mining opera-

equipment and other mission-critical

been done previously, the equipment

Similar to any other type of equipment,

requires contingency planning and emergency backup.

FIGURE 1 Pump performance curve

Total Head in Feet

BEP

“An optimised system includes built-in

Maximum Efficiency at this point

protection against downtime caused by equipment failure,” Maguire concludes. A rigorous approach and optimisation could have saved the Vlaklaagte operations a significant amount of time, down-

Efficiency

time and money. Source: South African Institue of Mining and Metallurgy & Xylem

FOR THE FULL PAPER, VISIT: http://bit.ly/1Ry78Lv OR http://bit.ly/1SwKhoD

IN SID E M IN IN G 0 3 | 2016

WATER MANAGEMENT

Striving for

zero liquid discharge

Water scarcity is probably the biggest driver for mining companies to strive towards zero liquid discharge (ZLD) during water and wastewater treatment. Therefore, new technologies and innovative solutions are at the fore of current and future practice.

O 16

NE EXAMPLE of new tech-

valuable chemical by-products and

that the system works via continuous,

nology is the continuous

metals. Carien van der Walt, process

counter-current movement of resin and

ionic filtration (CIF) system

engineer – environment SSM Division,

solution. “This means that resin moves

by CleanTeQ, which is avail-

Multotec Process Equipment, describes

in one direction, while solution moves in

able to Africa and South Africa through

the CIF technology as a unique, novel

another direction. Fresh resin contacts

Multotec. This ZLD treatment system can

form of ion exchange, working as a

the most concentrated solution and vice

typically be used in mines with acidic

dual-stage system when treating mine

versa. The concentration gradient drives

sulfate-dominant mine water, and has a

water. There are a set of columns for

the reaction,” says Van der Walt. This

range of applications to produce fit-for-

cation removal and another set for the

dual-stage system takes out the cations

purpose recycled water and potentially

anion removal process. She explains

(for example, calcium and magnesium)

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WATER MANAGEMENT

and nitrates) to produce the brine, or

FIGURE 1 The pilot plant clearly demonstrates what the system does Ca(OH)2

of the system to be neutralised. With this dual-stage system, one regenerates the cation system with sulfuric acid and the anion system with lime, both relatively

H2SO4 and Ca(OH)2

slurry, which goes back to the front end

Feed Water

Neutralisation

Clarification

DeSALx

Product Water

low-cost chemicals.

and the anions (for example, sulfates

“The calcium loaded onto the cation u

resin will produce calcium sulfate (also known as gypsum) during regeneration

Spent regenerant recycle solution for precipitation

Solid-Liquid Separation

with sulfuric acid, while the sulfates loaded onto the anion resin will also produce gypsum during regeneration with lime, thereby producing a calcium sulfate

u Solid Waste

slurry. This slurry will go back to the front end of the neutralisation step to precipitate out whatever calcium and magnesium is still remaining in the closed loop,”

including lower energy consumption • a reduced environmental footprint as a result of higher water recoveries

Many mines have valuables in their water, which are currently discarded, in a sense,” says Van der Walt.

explains Van der Walt. The total process

• less resin is required with this system

results in fit-for-purpose water, whether it

• suspended solids handling capabilities

technology that can recover the valua-

is process or potable water.

• ability to operate in high-scaling

bles in the water effectively, and which

and fouling conditions without

produces value from that, it is the type

pre-treatment

of innovation that the mining industry

Van der Walt adds that the size of the system can be designed according to the amount of dissolved solids that need to exit the system. For process-quality water, the system will be smaller than for

• ability to produce potentially valuable by-products at higher recoveries.

She concludes, “If a company has a

needs. This is where the CleanTeQ technology started. It didn’t start as a water treatment technology, but rather as

potable water, in which case the sys-

Features

tem will be designed for a greater res-

In most cases, there is no need to pre-

that water shouldn’t always be seen as

treat or pre-filter the water that enters

a problem but rather as an opportuni-

the CIF process. “Water is fed directly

ty. Also, water circuits on mines and in

into the adsorption column, where

industry should be looked at holistically,

dissolved salts are removed via ion ex-

rather than focusing on, or trying to

change. Suspended particles that enter

address, single aspects. She says this will

the system are filtered out within the pro-

result in water savings.

“We are moving to the point where companies invest in innovative solutions to do something that produces value at a lower cost.” Carien van der Walt

cess and, therefore, do not interfere with the desalination operation,” says Van der Walt. The system is also self-cleaning, as the continuous movement of resins

Carien van der Walt, process engineer, Multotec Process Equipment

means that the process is not subject to the normal scaling and fouling fail-

in capacity. The dual-stage system also

ure modes associated with membrane

acts as a filter, as the process removes

technology. The ion exchange resins are

suspended solids from the feed stream

continually cleaned and chemically re-

as well as dissolved solids. It is the contin-

generated before being reused, to en-

uous movement of the resin through the

sure that the primary treatment process

system, coupled with an external resin

continues to operate.

- washing step that allows for the high

metals recovery technology.” She adds

suspended-solids handling capabilities of

Future trends

the process. The system can also oper-

Van der Walt says that innovation is the

ate in series to remove multiple species,

key for the future of water and waste-

to recover valuable products from the

water management. “We are moving

water. Furthermore, the system also puri-

to the point where companies invest in

fies the water with its ability to operate in

innovative solutions to do something that

high-scaling or high-solids environments.

produces value at a lower cost.

Benefits

companies are seeing water as a val-

Besides the fact that this system is

ue stream, rather than just something

unique, it also offers benefits to the end

to treat and get rid of. I foresee that

users that include:

mines will look at how to use recycled

• lower capital and operating costs,

or effluent water to produce revenue.

“I also notice that more and more

IN SID E M IN IN G 0 3 | 2016

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WATER MANAGEMENT

Water-saving solutions for remote mines

Saving water has become an increasingly important aspect of operations, but is particularly difficult to do when managing mine water and wastewater in remote areas. Mientjie Kleinhans finds out what preengineered solutions to zero liquid discharge entail.

INS I DE MI N I N G 0 3 | 2 0 1 6

HESE DAYS IT is impossible to not

details water requirements and sources,

be fully aware of all the water

and a water management plan that

saving drives currently happening

mitigates the risks of too much or too

in the world. This holds true for the

little water at any one time. With the

mining industry too, which has been im-

current drought ravaging many areas

plementing water management systems

of Africa, ZLD becomes an extremely

as part of its environmental protection

important aspect of water manage-

programmes. Successful water man-

ment. Shepherd agrees and says that

agement has been quite a challenge

all containment facilities need to be

in remote and dry areas, and one of

appropriately designed to be able to

the possible solutions to this challenge is

collect dirty water from the mine so that

pre-engineered solutions to achieve zero

it can be reused in the plant or treated,

liquid discharge (ZLD).

where necessary and affordable.

Peter Shepherd, partner and principal

“What is particularly important is to

hydrologist, SRK Consulting, says that,

establish a hierarchy of water use that

if a mine is in a dry area and is remote

optimises the various qualities of wa-

from a water supply, recycling and

ter on the property. This requires that

reuse become critical in managing

potable water, for instance, be limit-

the water supply to ensure sustainable

ed to human consumption, and that

operations. The solution starts with a

lower-quality water be channelled to

proper water model for the mine that

purposes that suit those quality levels

WATER MANAGEMENT – such as dust suppression and process

Andrew Linington, executive: Water,

hydrological and hydro-

plant operations,” says Shepherd. John

Aveng Water, believes that prefabricat-

geological conditions.

Holmes, CEO, NuWater, says that the

ed and modular equipment is the solution

Holmes says that his

management of waste streams from

for mines in remote areas. “This equip-

company special-

water treatment and desalination

ment is built and commissioned off-site.”

ises in high-recov-

applications is a major challenge for

ery, completely

mines. On-site storage is increasingly

Benefits

difficult for practical reasons, such as

“The most important factor in pursuing

water treatment and

space and cost of storage ponds, as

a policy of minimising discharge from a

desalination systems. “In

well as for regulatory reasons, as the

mine site is the sizing of the dirty water

mining applications, our

necessary permits are increasingly diffi-

collection facilities – they must be capa-

system can recover up

cult to obtain.

ble of holding enough for the mine’s use

to 98%, leaving a largely

while also accommodating heavy rain-

dewatered waste stream

fall in the wet season,” says Shepherd.

for disposal. ZLD systems,

“Off-site disposal is costly but still, in most cases, the preferred approach. Therefore, minimisation of waste streams

modular and mobile

He adds that there is a fine balance to

Peter Shepherd, partner and principal hydrologist, SRK Consulting

where there is complete

is a priority. In the first instance, the

be struck between maximising the reuse

separation of dry salts, are generally not

elimination of liquid waste, or brine, is

of water on the mine and ensuring that

available in a modular and mobile solu-

the priority. This is far more cost-effec-

there is no spillage from these dams,

tion, but can still be pre-engineered for

tive than ZLD. In certain cases, ZLD is

which could have negative environmen-

rapid assembly on-site.

required and justifiable. Although, in

tal consequences.

theory, valuable commodities can be

High-recovery systems address many

These dams, therefore, need to be

of the applications seen in the mining

extracted from these waste streams,

carefully designed on the basis of sci-

sector and are more commercially via-

there are few instances where this fully

entific studies that show all the relevant

ble than ZLD solutions,” says Holmes. He

recoups the treatment cost. Rather, this

parameters, including the level in the

adds that NuWater’s focus is on solutions

is a possible way of offsetting a part of

dam due to rainfall and mine water

that are rapidly deployable and, where

the treatment cost,” says Holmes.

requirements, as well as geotechnical,

necessary, redeployable. In addition,

IN SID E M IN IN G 0 3 | 2016

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Distribution and Product Support by:

WATER MANAGEMENT the company owns and

Suzie Nkambule, gen-

operates the systems,

eral manager, Aveng

allowing customers to

Water, says that mining

avoid the cost and risk of

companies should look

acquiring and operating

around for different op-

plants themselves.

tions and involve industry

Linington explains that

specialists to find the

Aveng’s HiPRO-x system

optimum solution for the

is unique, as it is expand-

mine’s requirements.

able and adoptable

Adding value

to allow for change in wastewater quantity and/

Shepherd explains that SRK

or composition over the life of the plant.

rain- or groundwater from workings

Consulting adds value through its applica-

“Our systems are comprised of reverse

allows the mine to reduce the amount

tion of a risk-based approach to the issue

osmosis, desaturation reactors and brine

of outside water required – whether it

of water in the mining sector – measuring

treatment evaporators or crystallisers.” He

is pumped from nearby rivers or pur-

and understanding the mine’s risk of con-

adds that Aveng Water has the largest

chased from local municipalities. Reduc-

taminating the water resources in the sur-

mine water treatment production base in

ing discharge or run-off will also reduce

rounding areas. Detailed scientific studies

Africa and the company’s process design

the risk of contamination, which carries

create the foundation for designing miti-

and plant operation are proven on an

the potentially high costs of remediation

gation measures to minimise the risk.

industrial scale unmatched in Africa.

and legal proceedings,” says Shepherd.

Holmes concludes that water recovery

He add that well-designed tailings dams

and reuse is critical to the sustainability

are vitally important in any mine’s water

of the mining sector, both in South Africa

Shepherd says that the right design for

management plan, as this is where a

and globally. However, water treatment

a mine’s particular conditions can save

substantial portion of the mine’s water

and desalination need to be affordable to

costs in a number of ways. “Capturing

is stored.

ensure mining remains viable.

Cost savings

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IN SID E M IN IN G 0 3 | 2016

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PIPES, PUMPS & VALVES

Pumping emulsions as alternative explosives In a technical paper, titled ‘The Application of Pumpable Emulsions in Narrow-reef Stoping’, the author, SP Pearton, evaluates the viability of pumpable emulsion explosives for use in South African narrow-reef mining operations. A theoretical framework and suite of suitable equipment are proposed.

the quality of explosives manufactured

a gap in knowledge and technology.

at a central production facility, the

Consequently, the pumpable emulsion

ability to identify ‘out of spec’ sensitised

system hasn’t been introduced to the

emulsion in underground operations

narrow-reef environment. “The purpose

depends on the ability and training of

of the investigation was to evaluate the

the pump operator. Traditional emulsion

viability of pumpable emulsion explo-

charging units previously used for the

sives in narrow-reef mining operations,”

implementation of pumpable emulsions

writes Pearton. He explains that a study

on mechanised underground operations

was undertaken in order to gain an un-

are complex machines and, as such,

derstanding of the factors essential to

necessitate the allocation and training

the successful implementation of pump-

of a skilled technician for each unit in

able emulsions in narrow-reef operations.

order to ensure the correct performance

Pearton then discusses in detail the avail-

of the charging unit,” writes Pearton.

able explosives for comparative pur-

Pearton also writes that, given the

poses. He looks at ANFO, cartridge ex-

inflexibility of narrow-reef operations, a

plosives, pumpable emulsion explosives,

large number of pumps are necessary

and discusses the impact of poor explo-

for the implementation of pumpable

sive selections on the mine’s profitability.

emulsions on such operations. As a result,

New pump technology

it is no longer possible for every portable charging unit (PCU) to be accompanied

Pearton writes that possibly the greatest

by a trained technician to ensure the

challenge faced in the introduction of

quality of explosives manufactured at

UMPABLE EMULSION explosives

pumpable emulsion systems to nar-

the blast-face. With this in mind, the reli-

offer significant advantages to

row-reef operations is the manage-

ability of the PCU and its ability to deliver

mines regarding safety, relia-

ment of pump technology required for

consistent, sensitised emulsion without

bility and performance. They

their implementation.

continual calibration were deemed es-

have also been available to surface and

research in this regard has resulted in

“As pumpable emulsions are transport-

sential to the success of the project.

underground mining operations for dec-

ed underground as a Class 5.1 oxidiser,

ades, according to Pearton. He explains

the ability to manufacture explosives

within the workforce, safe operation of

that the benefits of pumpable emulsions

in the underground environment is de-

the pump technology was paramount

have been unavailable to narrow-reef

termined almost entirely by the reliabil-

throughout all operating conditions

mining operations due to the lack of

ity and consistency of the equipment

and all possible failure modes. All pos-

technology necessary for successful im-

used in charging operations. “While it

sible risks were to be identified, and

plementation in this environment. Limited

is comparatively simple to guarantee

multiple fail-safe modes incorporated

INS I DE MI N I N G 0 3 | 2 0 1 6

“Given the level of skills and training

PIPES, PUMPS & VALVES Portable charging units use sealed emulsion bags that do not require continuous refilling by a charging assistant. As a result, only a single operator is needed at a blast-hole into the charging equipment design so as to eliminate the possibility

ability of individuals to adjust the manu-

weight of only 14 kg, allowing the pump

facturing parameters of sensitised emul-

to be carried by a single operator, and is

sion in the underground environment. In

able to deliver a fixed mass of explosive

order to allow this to take place, it was

per blast-hole through the activation gun

essential that the charging equipment

on the charging lance. As the PCU uses

deliver consistent and repeatable results,

sealed emulsion bags that do not require

such that uniform settings applied to all

continuous refilling by a charging

charging equipment would produce con-

assistant (as is the case for

sistent sensitised emulsion on all pumps in

open tanks), only a single

use through the operation. This outcome

operator is required for the

needed to be achieved despite varia-

operation of the PCU,”

ble operation conditions that included

writes Pearton.

temperate fluctuations and changing air or hydropower pressure throughout the

Conclusion

operation based on both workplace and

In the conclusion, Pearton

time of day,” writes Pearton.

writes that, through the comparison of commercial

of dangerous pumping conditions,”

Operation

comments Pearton.

According to Pearton, the narrow-reef

narrow-reef mining operations, a number

emulsion system has been specifically

of improvements in safety and opera-

no longer available during daily charging

designed for use in confined stoping op-

tional efficiency have been proposed

operations, it would no longer be possible

erations. The system uses reuseable bags

through the implementation of pump-

for skilled personnel to check the quality

to supply emulsion and sensitiser to the

able emulsions. “Arguably the greatest

of explosives delivered to each blast-hole

pump, allowing the emulsion system to

advantage of pumpable emulsions lies in

during charging operations. “For this rea-

be used in previously inaccessible areas

their UN Class 5.1 classification. This clas-

son, a decision was made to remove the

within mining operations. “The PCU has a

sification has less stringent requirements

Pearton adds that, as technicians were

explosives available for use in

IN SID E M IN IN G 0 3 | 2016

www.polypipe.com/mining

PIPES, PUMPS & VALVES for legislation and control than those

of commercial explosives in criminal ac-

of bulk explosives is the full coupling of the

applicable to Class 1 explosives, allowing

tivities. Class 5.1 blasting intermediates

explosive within the blast-hole. Through full

for considerable advantages throughout

can be transported with other materials,

coupling, pumpable emulsions are able to

the transportation and storage of blasting

saving tramming and shaft time as well as

increase the energy available at the toe

intermediates,” writes Pearton. Pearton

allowing for longer storage periods under-

of the blast-hole, as well as the efficiency

adds that additional advantages of the

ground. “The bulk nature of pumpable

with which shock energy is transmitted

non-explosive classification of the system

emulsions gives them a number of advan-

from the explosive into the surrounding

are evident in the prevention of the theft

tages over prepackaged explosives sys-

rock mass,” writes Pearton.

of explosives and the downstream use

tems. Of greatest significance in the use

Pearton concludes that, from this study, it is evident that pumpable emulsions are

TABLE 1 Comparison of revenue and the direct cost of explosives for a panel (gold mining)

able to provide narrow-reef operations with increased levels of flexibility, efficien-

Panel length (m)

Burden (m)

0.5

Panel height (m)

1.2

Lines

Advance (m)

1.0 (83%)

Blast-holes per face

120

mercially available explosives. This increase

Rock density (kg/m3)

2.7

Mass per hole (kg)

0.8

in performance and efficiency through

Tons per blast (t)

Mass per face (kg)

96.0

Average grade (g/t)

6.0

Powder factor (kg/m3)

2.1

Gold produced per blast (kg)

0.6

Cost per kg explosive

R10.00

Gold price ($ per oz)

$1 260

Cost per fuse

R10.00

Exchange rate (R/$)

R10.20

Cost of explosives

R960

Rand gold price

R413 248

Cost of accessories

R1 200

Revenue per blast

R241 006

Total cost of explosives

R2 160

Explosives cost as % of revenue

0.9%

Cost per tonne broken

R22.22

cy, and control that are unavailable or limited through the use of alternative com-

the mining operation renders pumpable emulsions a financially desirable alternative to existing explosives systems within the narrow-reef environment.

FOLLOW THE LINK

Follow the link to the unedited white paper http://bit.ly/1OSpBk8

IN SID E M IN IN G 0 3 | 2016

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COMMINUTION

Not all mill liners are made equal The ultimate gain, when talking about productivity, is getting more for the same. Usually, when we talk about productivity losses, we talk about people problems; however, machines cause problems as well. By Tony Stone

ILL LINERS HAVE to be

principal types and materials used in the

tough. In a more dramatic,

construction of mill liners. There is just one

Hollywoodised sense, mill

qualifier – because of the factors men-

liners could be called “The

tioned by Jenkins, a direct comparison

problem of liner waste, as with solid lin-

Protectors”, which is what these compo-

of different liners is not really possible, as

ers. With two pieces involved, installation

nents really are. Battered all day, every

we would essentially be comparing ap-

and removal are a little more involved

day, by rough and tough elements, it’s

ples with oranges. Prof Malcolm Powell,

and time-consuming. During relining, if

what material liners are made of that will

of the University of Queensland and

determine their resilience, lifespan and

a director at Linear Design Servic-

cost. However, from the offset, it needs

es, said, at the 8th Internation-

to be said that it’s not just the material

al Comminution Symposium,

used but also the design of the liner, as

“The rule is simple.

well as other factors that, combined,

not well secured against the backing liner, the lifter can shift and work loose. This is particularly problematic when bolts begin to stretch.

The liner design and the

extend the life of a liner to ensure maxi-

material used in the liner’s

mum uptime.

construction are integral and

This point is driven home by Dean Jen-

cannot be chosen in isolation.”

• GRID LINERS: This liner system is unique to Southern Africa. It has pocketed grid

kins, managing director, Weir Minerals,

Clearly, Powel and Jenkins are in

who said, “Before an optimal design

total agreement. Against this backdrop,

packs into the grid structure and forms

and material can be recommended,

we look at the various types of liners

an integral part of the liner. These liners

a complete analysis is conducted

available and the materials used for

have a flat profile, which is suited to

for each milling duty. Factors such as mill dimensions, mill

their construction, and consider some of the merits of each.

speed, mill power, ore

liners where the grinding media

high speeds (85% to 90% of critical), and have been demonstrated to be economically unbeatable for highly abra-

type, feed top size, feed

• SOLID LINERS: As a solid,

sive ores in small-to-medium-size mills.

size distribution, through-

one-piece lifter and liner,

Light in weight, the liners make use of

put, charge volume and

installation and removal are

grinding media hardness to provide an

make-up, density and product size are considered.” With this in mind, we look at the

ABOVE Dean Jenkins, managing director, Weir Minerals ABOVE RIGHT Prof Malcolm Powell, University of Queensland, director at Linear Design Services

ABOVE Metso’s poly-met mill linings

INS I DE MI N I N G 0 3 | 2 0 1 6

easier. Once the lifter portion has worn down, and liner performance drops, a change-out is

effective wear material. Grid liners need to be manufactured using manganese steel to wedge the

necessary. Downtime is the obvious neg-

steel balls. However, it should be remem-

ative but, on the positive side, solid liners

bered that manganese steel spreads on

tend to have a higher scrap weight

impact and can make removal difficult.

once removed.

There is also the safety aspect to consider. The steel balls could dislodge and fall

• REMOVABLE LIFTER: Having a liner with

while workers are inside the mill doing

a separate, removable lifter solves the

inspections or relining.

COMMINUTION A thorough hosing down from a position of

• HIGH-LOW DOUBLE-WAVE BALL

safety will prevent this from happening.

MILL LINERS: This liner is a refinement of the integral wave liner. It provides a

• WEDGED LINERS: After the Second World

more consistent wear profile throughout

War, through to the turn of the new millen-

the liner’s working life. However, the

nium, the old-type wedge liners were quite

correct wave face angle needs to be

common. However, this type of liner was

calculated and applied.

dangerous to install and is no longer in use.

If an incorrect angle is calculated, it

A new type of wedge liner is currently in use

will lead to ball segregation and loss

where the liner blocks are wedged in by

of grind. As with the different types of

bolted lifter bars.

liners, the selection of material from which a liner is constructed is also

• INTEGRAL WAVE BLOCKS: Commonly used

quite complicated.

A Metso 32' x 32' SAG mill

in ball mills today, because technology has

The choice is a function of the applica-

advanced and become sufficiently sophis-

tion, the abrasiveness of the ore, the size

ticated, this integral wave block liner main-

of the mill, the corrosiveness of the en-

and can withstand extreme impacting

tains its profile even as it wears – retaining its

vironment, the ball size and mill speed,

without fracture. Its disadvantage is

effective ness for longer.

among others. The primary mill liner con-

that it spreads with impact, so solid

struction materials, their particular uses

liners begin to squeeze together and

and the strengths of each are:

become extremely difficult to remove,

• UNIDIRECTIONAL PROFILED LINERS:

and can damage a mill shell if the

The lifter of this liner has different leading and trailing profiles. It allows for better cus-

• Austenitic manganese steel (AMS):

stress is allowed to build up over time to an extreme level.

tomisation, to suit mill speed, and filling –

This material is used for grid liners and

optimising performance. It also allows more

smaller mills, generally. The advantage

material in the lifter for a given base width,

of this material is that it hardens under

but the mill must run in one direction only.

stress while the substrate remains tough

• L ow-carbon chrome moly steel (300 to 370 BHN): This material was

IN SID E M IN IN G 0 3 | 2016

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COMMINUTION generally used for mill liners (AG, SAG

Duane Mathers, regional product support manager, Metso

and ball) prior to the change to higher-carbon-content steels. It has excellent wear characteristics with some impact resistance and is now generally used for discharge grates where slightly better impact resistance is required, particularly for thinner section liners. • High-carbon chrome moly steel (325 to 380 BHN): This steel is now considered the main material used for SAG mill liners. There are a number of variations with either different carbon or chrome contents. The variations tend to have a bearing on the size of the liner and its section thickness. There is ongoing development within this area, as the size of the liners is outstripping the properties provided by the standard, high-chrome moly steels. • Nihard iron (550 BHN): Given the use of high-chrome irons and chrome moly white iron, the use of this material is now considered obsolete. • High-chrome irons (+600 BHN); CR iron: This material is considered to have superior wear abrasion characteristics, and is generally used in rod and ball mills. It is more cost competitive but is more brittle than chrome moly white irons. • Chrome moly white irons (600 to 700 BHN); WI: This material is considered to be the ultimate material developed and is used specifically for abrasion resistance in milling. It is commonly used in cement mills and some of the largest ball mills in the world, and where performance has not been bettered to date. • RUBBER LINERS: Linatex, a Weir trademark product, is a 95% natural, cured rubber that exhibits outstanding resilience, strength and resistance to cutting, tearing and abrasion. It also offers ease of installation and a reduction of costly maintenance and downtime.

Nothing is as simple as it seems The best solution, when looking to buy a grinding mill, is to consult the experts. And, as usual, it’s not just the original purchase that is important – the time and cost components of ongoing maintenance need to be seriously considered as well. A total “needs” package approach is recommended. “When it comes to mill liners, there are quite a lot of factors that can influence the performance of a mill. At the end of the day, one needs to find a balance between liner life, throughput, grind, safety and other factors, with safety being the first consideration. It is vital to understand what the customer needs, what is important and what the processes are. This should be the starting point for any liner design,” stated Duane Mathers, regional product support manager, Metso. In the final analysis, this is the crux of the matter. If not, it will break the bottom line.

IN SID E M IN IN G 0 3 | 2 0 1 6

COMMINUTION

Eyeing energy efficiency

The first step to reduce energy consumption in mineral processing is to optimise plant lighting

Investing in a mine can run into the millions, even billions. A large portion of these investments go into mineral processing, which generally has high operating costs – mainly due to high levels of energy consumption. Can this expense be cut? By Tony Stone

NERGY USAGE in mineral pro-

of the circuit itself that will make the

collected on the nature of ore

cessing operations is anything

comminution circuit energy efficient.

bodies and rock feed to

between 33% and 40% of the

Moon’s comment about design is ech-

inform technological op-

total. And, of all the mineral

oed by the Australian government’s

tions for downstream

processes, comminution circuits are the

Energy Efficiency Exchange, an initiative

crushing and grinding

most energy intensive. Given Eskom’s

established to assist miners in becoming

processes. These tar-

past tariff increases and its demand

more energy efficient. The government’s

get the highest ore

for a 16.6% increase in 2016, cutting

research concludes that, to get an ef-

grade concentration

electricity consumption becomes even

fective comminution strategy up and

when blasting, which can

more critical, even survivalist. Looking at

running, it requires strong management

Table 1 (pg 33), one can appreciate the

support and a focused energy man-

impact of Eskom’s tariff increases on the

agement team to identify “mine to mill”

mining sector. The key question is, given

cost inefficiencies and come up with

that mines have been active in energy

workable solutions.

optimisation, is it possible to cut electricity consumption even more? “To be energy efficient, a mineral processing circuit needs to have the right equipment, and that equipment must be optimised. Even the most efficient equipment

Dr David Danielson, who leads the

reduce energy use by 10% Dr David Danielson, to 50% of metal per tonne. Office of Energy • Discrete element method Efficiency and Renewable Energy modelling provides a dein Australia tailed exploration of particle flows and breakage

Office of Energy Efficiency and Renew-

processes. This can be used for the

able Energy in Australia, recently said,

design and rapid manufacture of new

“Mines need the capacity to measure

comminution equipment as well as

and collect data to understand what impact different operations have on each other and what the

improving existing equipment.

Mobile circuits

installed in an improperly

overall energy use is across the

Mobile crushing and screening plants

matched process will not

mine’s operations.” Advances

are energy efficient because they are

be energy efficient. A key

in modelling and data collec-

purpose built using integrated designs,

tion increasingly offer better

which incorporate advanced engines,

dependency is an energy-efficient process design,” says Dave Moon, vice-president: Southern Africa, Metso. In a nutshell, it’s not just the comminution

and more informative insights to managers to improve their com-

electric motors and hydraulics, and power transmissions. Material is typically

minution processes. These include:

fed via a lifting conveyor to stacked,

• Energy-mass balance models use

vibrating screens. Oversize material is

components, crushers and screens, and

baseline data to identify energy and

conveyed to a cone crusher and the

electric motors, but more the design

mass flows, and any external factors

screened material is divided and passed

likely to impact on the efficiency of

to the sized product conveyors. After

processes and equipment.

the material is crushed, a revolutionary

ABOVE Dave Moon, vice-president: Southern Africa, Metso

• Geometallurgy data should be

centrifugal lifting conveyor returns the

IN SID E M IN IN G 0 3 | 2016

COMMINUTION A comminution circuit showing a jaw crusher

material back to the screen in a closed circuit. Power is supplied either by using an external source, or from an on-board 500 kVA diesel generator.

Energy reduction case study Some years ago, Cristian Tezza, a WEG engineer based in Brazil, initiated a rather innovative project with a customer who operated a chip stone quarry for the civil construction industry. Tezza’s idea was to test frequency inverters, or variable-speed drives (VSDs), on several of the electric motors. The results were quite amazing. The quarry’s jaw crushers had been supplied by, among others, Metso, Remco and Sandvik. The jaw crushers, with their two motors, which needed to be synchronised for optimal efficiency, were not fitted with VSDs at the time. Once the changes had been made and WEG inverters fitted, tests were carried out

INS I DE MI N I N G 0 3 | 2 0 1 6

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COMMINUTION

Schematic of a mobile cone crusher

loads, especially in the case of conveyor belts, was also reduced. The classification of the material by screening is a

using various motor speeds during crush-

dynamic process. Regulations require

ing operation. It was found that the jaw

changes of the vibratory counterpoises

crushers operated best, and produced

of the screens to obtain an ideal classifi-

high-quality product, at a lower speed

cation. With the use of VSDs in this stage

than the motor’s rated speed. At the

of the process, the operator can set the

same time, a near-double

speed and visually identify

increase in productivity

the ideal point for each type

was achieved.

of stone and load. Beyond

The quarry owner also

these benefits, the quarry also

reported a better shape

reported a reduction in me-

of stone (cubic/rectangu-

chanical breakdowns, due to

lar) after crushing, which

the frequency inverter’s ability

improved his customers’

to soft-start and soft-stop vi-

quality of concrete. While this alone justified the investment in the VSDs, the cherry on the top came a month later when the electricity bill arrived. Energy

Milton Castella, engineering director, WEG, with Demétrio Amono, director of Rio de Janeiro-based newspaper O Globo

savings of about 20% had been achieved.

brating screens – which avoids breaking the screens’ supporting springs. For its ongoing efforts in innovation, WEG was one of the winning companies of the AT Kearney Best Innovation Awards in Brazil. “We

continuously create mechanisms to

Besides the crushing processes, the

allow new ideas to flow in a natural way,

quarry started to use inverters on con-

suggested by internal workers, discussion

veyor belts, screens and peripheral sys-

groups and committee meetings,” Mil-

tems. The overall energy reduction was

ton Castella, engineering director, WEG,

amazing. Energy consumption, in the

says. “Innovation initiatives are part of

case of constant or quadratic torque

our company culture.” he adds.

TABLE 1: Approved Eskom tariff increases vs inflation

Wrapping up

Year

Avg % increase Avg % inflation

2008

27.50%

11.50%

older quarries and

2009

31.30%

7.10%

mines still in operation,

2010

24.80%

4.30%

2011

25.80%

5.00%

2012

16.00%

5.70%

2013

8.00%

5.70%

motors and save a lot

2014

8.00%

6.10%

of money. With Eskom

2015

8.00%

4.50%

so voraciously chasing

2016 Nersa-approved 12.70%

5.20%

Total

55.10%

162.10%

With the number of

and even more modern mines, it is clear that they could install VSDs on their electric

unreasonable tariff increases, VSDs must be a serious consideration.

I N S I D E M IN IN G 0 3 | 2 0 1 6

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MATERIALS HANDLING

Risk-based approach to design Rail-mounted BMH equipment, like stackers and reclaimers, needs to be custom-designed to avoid structural failures. Several case studies have provided insight into design considirations. By Mpinane Senkhane

N THE JOURNAL article ‘Avoiding

problem here lay in the underestimation

structural failures on mobile bulk ma-

of the loading conditions; an incorrect

terials handling', MJ Schmidt and BWJ

material bulk density was used in the ini-

van Rensburg recommend a number

tial design. “The incorrect commissioning

of remedies for improving the overall

of the speed switch settings associated

safety of mobile bulk materials handling

with the boom belt contributed to the

equipment. They do this by focusing on

structural overloading of critical tie-beam

aspects specifically related to the design

connections when slippage of the boom

integration and commissioning of protec-

belt occurred.”

tion systems and controls.

Collapse of a reclaimer

Structural damage to drum reclaimer

A reclaimer had been in use for a few

In the third case study, although no failure

months without the use of a collision pro-

actually occurred, there was a significant

tection system. At the time of collapse,

amount of damage to the drum reclaim-

the designed reclamation rate had been

er legs when a malfunction occurred.

exceeded by approximately 30%, and

“The overall machine control system

the stockpile proximity probes appeared

was originally configured without in-

to not be working, resulting in unexpect-

terlocks between the independent

edly high digging forces that led to the

long-travel drive systems located on ad-

failure of major structural connections.

jacent bogie wheel sets.” It was revealed

Schmidt and Van Rensburg write, “The

that insufficient design integration existed

lateral resistance of the machine was

in the engineering process and, although

insufficient to withstand the forces gen-

the machine had been used for years

erated within the structure when exces-

before the malfunction, the damage that

sive digging was experienced.” It was

eventually occurred “could have been

revealed, in the investigation following

avoided by the incorporation of addition-

the incident, that there was a “lack of

al protection instrumentation for negligi-

proper design and integration between

ble additional capital cost.”

the mechanical, structural, electrical and

Schmidt and Van Rensberg make a

control and instrumentation engineer-

number of recommendations, some of

ing disciplines.”

which include that the structural designer

The authors emphasise how imperative

in any BMH process be closely involved

it is that there is adequate interaction

with the verification of alarms and set

between the control and instrumentation

points associated with machine protec-

teams and the structural and mechanical

tion systems.

designers in a bid to avoid miscommuni-

In addition, “A high level of interdiscipli-

cation and misinterpretation. As seen in

nary design integration must be pursued

this case, a lack thereof can be disastrous.

with specific reference to machine pro-

Collapse of a slewing stacker The stacker used in this instance had

tection systems and controls. A risk-based design approach should be mandatory,” the authors conclude.

been in use for in excess of a year before the systems failure collapse occurred. “An incident in which the boom and conveyor belt were overloaded preceded the failure event,” the authors write. The

FOR THE FULL PAPER, VISIT: http://www.saimm.co.za/ Journal/v115n03p179.pdf

I N S I D E M IN IN G 0 3 | 2 0 1 6

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COMPANY NEWS

Streamlining operational efficiencies The Operations Division is at the heart of SEW-Eurodrive, and the division’s newly appointed general manager, Greg Perry, is eager to consolidate on current successes to improve service delivery.

engineering. Despite the fact that the

ment. As a result, customer service is

company is well-recognised as a market

more important than ever, and we are

leader in innovation and quality, Perry

adopting a continuous improvement

admits that more needs to be done to

approach in that regard,” he states.

maintain current clients and win over

Bearing this in mind, Perry believes that

new ones in tough economic conditions.

SEW-Eurodrive will maintain its compet-

“Our products are good, and we have

itive edge in industries such as mining,

every confidence in them in terms of de-

automotive, food and beverage, and

sign and functionality. Due to a gradual

water treatment. “Our business model

slowdown in new investments, a general

is sound and we have a strong team of

HE SCOPE OF the company’s

industry trend is that operations are

Operations Division encompasses

reducing overhead costs by diverting

numerous functions, including:

budgets towards maintenance to

production, logistics, services and

extend the total life cycle of equip-

Greg Perry, general manager, SEW-Eurodrive people behind our products; however, it is important to work smarter in challenging times, and we are doing this by taking a proactive approach towards streamlining efficiencies across the board.”

www.sew-eurodrive.com

IN SID E M IN IN G 0 3 | 2016

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COMPANY NEWS

Going local improves

competitiveness M Screening and vibration equipment specialist Aury Africa has gained the edge over its competitors, particularly in the coal mining sector, by continuing to offer the market its own brand of products – of the same high quality as the most well-known brands – at a more competitive price.

Mark Houchin, managing director, Aury Africa

ARK HOUCHIN, managing

design of the system.” The Aury Africa

director, Aury Africa, says

PU products that are due to be manu-

that cost-cutting is a major

factured locally with the new injection

trend in coal, and all com-

moulding machine include:

modity sectors. “Even though the mines

• modular wedge wire panels

are running leaner, we are actually being

• PU cross-tensioned screen cloths

exposed to larger players who are mov-

• PU long slots

ing away from their regular suppliers that

• punch plate screen panels with

have traditionally dictated prices. This

PU borders in 305 mm x 305 mm and

is where our company adds real value,

305 mm x 610 mm and

as we offer the exact same quality of product at a better price, which is exact-

610 mm x 610 mm • edge wire screen panels with PU bor-

ly what the market currently requires,”

ders in 305 mm x 305 mm and

he explains. Houchin is optimistic that the

305 mm x 610 mm and

company will gain even further traction in the coal mining sector in 2016, following the February arrival of the company’s new gravity-pour polyurethane (PU) mould-ing machine. “We previously imported our PU panels

610 mm x 610 mm • PU panels in 305 mm x 305 mm and 305 mm x 610 mm, including pin and sleeve. Houchin adds that local manufacture of PU products will also assist the company

from our sister company in China. How-

in reducing its high stockholding. “Ac-

ever, given the ongoing volatility of the

curately anticipating client demand is a

rand, local manufacture is the logical

challenge that often results in very high

option. “Although our prices have always

stockholding. It is counter-productive to

been attractive, the poor exchange rate

have thousands of products valued at

has resulted in our margins being erod-

millions of rands just lying in a warehouse.

ed. Local manufacture will enable us to

Local manufacture will enable us to

remain competitive with regard to both

significantly reduce this number, there-

pricing and profit margins. What is more,

by improving efficiency and cash flow

we can upskill our staff and provide the

in challenging economic conditions,”

market with high-quality products in short

he concludes.

turnaround times,” he continues. Houchin explains that the hand-cast

What is more, Aury Africa offers a hybrid fixing system that allows its PU panels to

gravity-pour PU moulding machine is

be installed alongside existing panels. This

modular, thereby enabling the company

hybrid fixing system has allowed custom-

to expand capacity as and when it is

ers to freely choose which supplier they

needed. “We have already prepared a

use, as they are no longer bound by a

sealed room for the machine to be in-

patent or a specific structure.

stalled in, and we anticipate production to begin soon. Although production will be small-scale to begin with, we have the advantage of being able to keep up with rises in demand, and even eventually automate, thanks to the modular

INS I DE MI N I N G 0 3 | 2 0 1 6

www.auryafrica.co.za

EVENTS The overall consensus from discussions at the Canadian Interactive Breakfast Forum, held at the Mining Indaba, was that government and various mining industry stakeholders have been working together, but there is still a long road ahead. By Mientjie Kleinhans

Progress in the mining industry year. But, there are a lot of factors that

for about a year. The minister said, at

impact on the mining industry that are

the opening of the Mining Indaba, that

within our control, and that we do have

there will be fast tracks. I am still not sure

the ability to do something about. What

what happened to this bill or why it was

do you think are the most important

left lingering in parliament for a year.” He

factors that are within our control and

explained that the bill is not always clear

what is our roadmap for addressing

about when and under what circum-

those challenges?” Oliphant responded

stances licences will be granted, or the

that the mining industry in South Africa

time limits that may apply.

is complex, huge and

industry that the president announced

munity is very strong.

two years ago should be written into the

He also commented

law. Mining companies should apply for

that the DMR is aware

mining rights and, if the application is

of the factors that

compliant, they should be able to get

influence the mining

the rights within 300 days. ” said Leon.

sector and that the

The panel at the Canadian Breakfast Forum 2016

“The one-stop shop for the mining

rich, and that the com-

industry should learn

Is there hope?

where possible. “We

Du Toit asked if there is hope and Baxter

should also learn from

responded that he thinks South Africa

China – we should not

is going through continued transition. “I

have a single market

think there is a lot of focus on a number

that consumes all our

of different players who can make a

focus, while we ignore

difference and I think it all comes down

HE THEME FOR this year’s breakfast

other promising markets. What can we

forum was ‘Building Momentum

do better? “We have the Mining Opera-

to collaborative leadership. “It is not ongoing political changes

for the South African Mining Sec-

tion Phakisa. We had a whole six weeks

that have created some challenges for

tor’, and industry leaders had

of focus on the mining industry to check

the economy as a whole in the last cou-

an opportunity to discuss a few issues

what we can do better and how we

ple of months. It is not just about infra-

currently pertaining to the mining in-

can get faster results.

structure, the cost, nor the challenges

dustry. Sandra Du Toit started the forum

Our geology is so different that we

around policy uncertainty. As much as

by commenting that the population at

have been mining in this country for

we do have a good foundation policy

the Mining Indaba of 2016 was skinny

over 100 years. We are so confident

in place,

and that the conversations, in general,

with the resources that we are sure we

there is uncertainty about the interpre-

were particularly harsh. “We had CEOs

have another 100 years of mining left.

tation of the Charter. There is uncertainty

of major mining companies airing their

The difference is that we have to do it

on development pricing issues, and we

thoughts that 2016 is going to be one of

better,” replied Oliphant. Oliphant men-

are still waiting for the final bill to come

the toughest years that we have seen in

tioned three points that he felt need to

out. But, again, government indicated

the mining industry.”

be addressed in the mining industry.

that it might finalise the bill by the

Influencing factors

Policy framework

middle of the year.” “We do have a plan; it touches on

Her first question was directed to the

The next question went to Peter Leon.

a whole ray of issues. When it comes

deputy minister of the Department of

“Will it be enough to lead with the pol-

to consultation, dialogue and so on,

Mineral Resources (DMR), Godfrey Ol-

icy framework? Are we going to do

let’s use the strength of our South Af-

iphant. “There are a number of factors

enough in the next round of changes to

rican transition. Transformation and

negatively impacting on the mining

establish the certainty that the industry is

transition are about negotiation. That is

industry that are beyond our control,

looking for?”

why systems and strategies have been

such as the growth of China, lower

Leon, partner and co-chair: Africa,

introduced since 1994. We are in talks

commodity prices, a number of mac-

Herbert Smith Freehills, responded to the

with people to discuss issues such as

ro-economic factors and challenges

question: “We have to acknowledge

employment. Let us handle it with care,”

that contribute to 2016 being a tough

that there were delays in parliament

concluded Oliphant.

IN SID E M IN IN G 0 3 | 2016

EVENTS

Mining Indaba round-up

NE OF THE INTERESTING

firm baseline, which brings out an un-

launches at the Mining Ind-

derstanding of alternative restrictive

aba was the Africa Mining

socio-economic practices, stronger

Vision (AMV) compact be-

accountability and transparency of

tween African governments and mining companies. Frank Dixon Mugyenyi, sen-

certain groups of society in participating in inclusive practices.

ior trade advisor, Department of Trade

“For Africa to achieve these policy shifts,

and Industry (dti), in the Africa Union

there is now an urgent need to build and

Commission (AUC), explained that the

strengthen mechanisms and partnerships

compact is a concrete step forward in

at all levels – in particular, with the pri-

aligning key interests around the imple-

vate sector leaders,” said Mugyenyi.

mentation of the AMV with those of the business community. “The goal of the compact is to

Supporting resilient communities One of the themed panel discussions at

The African Mining Indaba has always been an opportunity for mining industry stakeholders to partake in discussions, attend forums, meet with exhibitors, and make announcements. Inside Mining takes a look at some of the highlights of this year’s event.

strengthen trust and mutual understand-

the African Mining Indaba was: ‘Support-

ing of challenges as well as opportu-

ing Resilient Communities’. The modera-

nities for implementing the AMV,” said

tor of the session was Sheila Khama, di-

Mugyenyi at its launch. The compact

rector, African Natural Resources Centre

outlines standards, commitments and

(AfDB), and King Kgosi Leruo Molotlegi,

in long-term planning. We need long-

undertakings by the committed gov-

of the Royal Bafokeng Nation, delivered

term strategic vision in order to be able

ernments and mining companies to

the keynote speech.

to harness resources for the benefit of

Khama asked about the impotency

the community.” He added: “We must

said that, in order to optimise the contri-

of transparency in creating resilience

align our priorities in order to come up

bution of the mining sector to the nation-

among communities, particularly during

with strategies and policy recommen-

al economy, the AMV compact calls on

the economic downturn currently ex-

dations that allow all stakeholders to

African governments and private sectors

perienced by the minerals sector. In her

harness the benefits from this sector in

to embark on the following general

long term.” question, she specifically referred to theDoosanthe Business Card ad.pdf

achieve the goals set out in the AMV. He

AMV. Panellist Kojo Bu-

policy shifts: • commitment towards the creation

2016/02/26

2:19 PM

sia, coordinator, African

of effective public-private partner-

Minerals Development

ships, the building of knowledge,

Centre (AMDC), an-

networking and niches involving

swered: “The consensusM

academia, civil society industry and

around sustainability,

government actors

both in and outside

• the establishment of systems-approach

of the industry, is that

framework, which should support

we have moved to a

efforts towards identifying binding

broader understanding

constraints on the industry and build

of the role mining plays

capacity, and practical steps required

in the national economy

in strengthening local content and

and in the communi-

value addition

ties, and all of them

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