annual report - 2008-9

20082009
annual report
COALTECHresearch association

COALTECH
RESEARCH
ASSOCIATION
http://www.coaltech.co.za

Coaltech Research Association 3
contents
chairman’s review .................................................................................... 4
coaltech structure.................................................................................... 5
steering committees ................................................................................ 6
a celebration of 10 years ......................................................................... 8
research highlights................................................................................. 12
ﬁnancial statements............................................................................... 57
coaltech annual report
2008/2009

4 Coaltech Research Association
T
he years 2008 and 2009 was characterised by economic turmoil.
While the beginning of the year was marred by the electricity crisis in
South Africa, the commodity boom was still in full swing during April
2008. The price of export coal had risen to record levels and in South Africa
the demand for coal was also at unprecedented levels as Eskom was acquir-
ing additional coal to rebuild stockpiles.
From October 2008 the situation changed dramatically. Due to the global
economic downturn, the demand for electricity – and consequently Eskom’s
coal consumption – decreased significantly. At the same time the price of
export coal decreased to pre-2008 levels.
Despite the downturn, the support for the Coaltech Research Association
remained strong and three additional Associate Members joined Coaltech
during this period.
At the beginning of the year it became clear that the South African coal
mining industry needed to confront a number of challenges if it was to remain economically sustainable and retain
its social licence to operate. These challenges included increased resistance to coal mining from environmental
civil society, an escalating water scarcity, global climate change, constrained coal transport capacity, a diminish-
ing resource in Mpumalanga and the need to open up a new coal field in the Waterberg.
Consequently Coaltech developed a strategy to address these challenges during the next five years. The strat-
egy includes a focus on the waterless beneficiation of coal, improving the utilisation of coal resources, environ-
mental conservation and rehabilitation, infrastructure development, the development of the Waterberg coalfield
and clean coal technology. In addition, energy efficiency was to be an aspect of all projects.
In accordance with the strategy, Coaltech – while continuing with projects in progress – also embarked upon a
number of new projects concerning dry dense medium separation and dry screening of coal, more efficient water
treatment technologies, the mitigation of spontaneous combustion, the improved utilisation of rehabilitated mine
land and coal transport.
The year under review is also significant in that Coaltech completed its first ten years of operation on
31 March 2009. During the ten years the Coaltech model – in which personnel from all levels in the coal mining in-
dustry are involved in the selection and guidance of projects – proved its efficacy and resilience. This model also
mitigates the issue of technology transfer, which remains a challenge for some other research undertakings.
In conclusion I wish to thank the members of the Coaltech Board for their support and guidance during a chal-
lenging period. In addition I wish to express appreciation to the representatives from the universities of Pretoria
and the Witwatersrand, the National Union of Mineworkers and the Department of Minerals and Energy, all of
whom contributed their expertise and time to assist the Board.
I also wish to pay tribute to the members of the Steering Committees for their unstinting support and contribu-
tions in guiding the work of Coaltech.
Finally I wish to convey the gratitude of the Board to the manager of Coaltech, Johann Beukes, and his ad-
ministrator, Carmen Bergman-Ally. Their dedication and perseverance played an immense role in the successes
achieved by Coaltech during the year.
Dick Kruger, Chairman: Coaltech Research Association
chairman’s review

coaltech structure
directors
Dick Kruger, Chamber of Mines – Chairman
Gerhard Jonck, Exxaro – Vice-chairman
Johann Beukes – Company Secretary
William Osae, ARM Coal
Stan Pillay, Anglo Coal
Stefan Venter, Xstrata
Vic Cogho, Optimum
Gerhard Smith, CSIR
Noddy McGeorge, BHP Billiton
Schalk van Wyk, Sasol
by invitation
Frans Knox – BHP Billiton
Thabo Dube – Department of Minerals & Energy
Huw Philips, University pf the Witwatersrand
Brian Roberts, Total Coal
Johan Dempers, Eskom
Ronnie Webber-Youngman, University of Pretoria
Ephraim Malahlela, National Union of Mineworkers
David Nkuna, National Union of Mineworkers
geology &
geophysics
coal
processing
surface
environment
human &
social
aspects
engineering
underground
mining
surface
mining
steering committees
coaltech board
coaltech board

steering committees
geology & geophysics
Marius Smith, Xstrata Coal – Chairman
Johan Dempers, Eskom
Claris Dreyer, Exxaro
Michael van Schoor, CSIR
Pat Eriksson, University of Pretoria
Leon Pienaar, BHP Billiton
George Henry, CSIR
John Ndwamise, Anglo Coal
Iwan de Jongh, Xstrata
Bruce Cairncross, University of Johannesburg
Lesley Jeffrey, CIC Energy
Riaan Joubert, Total Coal
Stoffel Fourie, CSIR
Viren Deonarain, Sasol
Simon Mokitimi, BHP Billiton
Jannie Marais, BHP Billiton
Frans Schutte, Exxaro
Chris van Alpen, Eskom
Gustav Trichardt, Elementary Energy
underground mining
Neels Joubert – BHP Billiton – Chairman
Brian Roberts, Total Coal
Neels Joubert, Sasol
Dave Roberts, CSIR
Nielen van der Merwe, CIC Energy
Jasper Coetzee, Sasol
Christian Teffo, Chamber of Mines
Wellington Chirigo, Kangra Coal
Stan Pillay, Anglo American
John Flannigan, BHP Billiton
Steve Roos, Exxaro
Andre Dougall, SRK
Ronnie van Eeden, Eskom
Ronnie Webber-Youngman, Pretoria University
Kalello Chabedi, Wits University
surface mining
Henk Lodewijks, Anglo Coal – Chairman
Stefan Adamski, Exxaro
Conri Moolman, BHP Billiton
Nielen van der Merwe, Bon Terra
Huw Philips, University of the Witwatersrand
Fatima Ferraz, Anglo American
Dean Hoare, BHP Billiton
Cezar Uludag, Anglo American
Kalello Chabedi, Wits
Barry Bezuidenhout, BHP Billiton
Andy Johnson, Sekoko
Derek Anthony, AEL
Andre Pienaar, AEL
William van der Walt, BME
engineering
Ertjies Ernst, BHP Billiton – Chairman
Mark Acutt, Anglo Coal
Ronnie Anderson, Eskom
Eric Croeser, Exxaro
Pieter van der Walt, Sasol
Jasper Coetzee, Sasol
Fritz van Eeden, Kangra Coal
Anthony Coutinho, Department of Minerals &
Energy
Martin Gibson, Sasol
Buks Loock, Xstrata
Jeroen Maaren, Mechaneer
Nelson Pillay, Exxaro
Ferdie Smith, Exxaro
John Page, BHP Billiton

coal processing
David Power, Anglo American – Chairman
Kobie Badenhorst, Total Coal
Johan de Korte, CSIR
Jakes Jacobs, Xstrata
Setobane Mangena, Sasol
Thulani Ndlovo, Sasol
Thabo Rabotho, Eskom
Pieter van Heerden, BHP Billiton
Mark Whitter, Eyesizwe
Mientjie van der Vyver, Exxaro
Dave Tudor, Anglo American
Johannes van Heerden, Sasol
Nielen van der Merwe, CIS Energy
Michael Moys, Wits University
Lydia van der Merwe, Total Coal
Rosemary Falcon, Fossil Fuel
Gustav Trichard, Elementary Enery
human & social aspects
Dick Kruger, Chamber of Mines – Chairman
Ephraim Malahlela, National Union of Mine-
workers
Maphefo Makgamatha, Mpumalanga Local
Government
Sarel Lessing, Xstrata
Riaan de Villiers, Exxaro
Sarel Booyens, Sasol
Clarens Esau, Eskom
David Nkuna, National Union of Mine Workers
Lester Peter, Eskom
Mavis Ann Hermanus, Wits
Thandi Mokotedi, Mpumalanga Provincial
Government
Themba Mataka, Mpumalanga Provincial
Government
Elize Strydom, Chamber of Mines
Nikisi Lesuﬁ, Chamber of Mines
Julie Stacey, Wits
Annelie Naude, Wits University
Tsheko Ratsheko, Exxaro
surface environment
Dirk Hanekom, Eskom
Leslie Petrik, University of the Western Cape
Peter Gunther, Anglo Coal
Sharon Clark, BHP Billiton
Nico Dooge, Xstrata
Nielen van der Merwe, CIC Energy
Bertie Botha, Sasol
Kevin Kirkman, KwaZulu-Natal University
Norman Rethman, Pretoria University
Solly Motaung, CSIR
Lucas Nengovhela, Optimum
Piet Wessels, Xstrata
Wayne Truter, Pretoria University
Charles Linstrom, Exxaro
Hallam Payne, UKZN
William Pulles, Golder Associates
Jo Burgess, WRC
Melanie Naidoo-Vermaak, Eskom
Ralph Heath, Golder Associates
Nikisi Lesuﬁ, Chamber of Mines
Gustav le Roux, Anglo Coal

T
he Coaltech Research Association was established in 1999 as the Coaltech 2020 Research Pro-
gramme, a collaborative initiative with the vision to develop technology and apply research findings
to enable the South African coal industry to remain competitive, sustainable and safe well into the
21st
century.
Initially its focus was on extending the useful life of coal mining in the Witbank/Highveld coalfield, while
sustaining employment opportunities and utilising the available infrastructure to the year 2020 and be-
yond.
Since then the programme has, over a period of 10 years, made the switch from association to a Section
21 company, re-located its premises and extended its research beyond the Highveld to include more than
100 successful research projects (either completed or still ongoing).
in the beginning
It all started in 1997 when the mining technology division (Miningtek) of the Council of Scientific and In-
dustrial Research (CSIR), the University of the Witwatersrand (Wits) and the University of Pretoria (UP) set
up a cooperative research programme for four gold mines. Known as Deepmine, the programme’s goal was
to do research on mining conducted between 3 000m and 5 000 m underground.
a celebration of 10 years

The model was so successful that the three partners decided to investigate the possibility of setting up
such a model for the coal industry.
The original objective was to establish a sustainable forefront technology and human resource base to im-
prove the overall productivity and reduce the costs incurred by South African coal mines, in order for them
to be and stay internationally competitive. To achieve this, Coaltech 2020 had five goals:
- to develop a new coal mining research programme,
- to increase the human resource capacity for research and development,
- to establish a culture of innovation,
- to encourage rapid technology transfer and implementation, and
- to extend the useful life of existing mining operations and other infrastructure.
Getting started
Experts from industry, the state
(through the Department of Minerals
and Energy – DME) and labour (the Na-
tional Union of Mineworkers - NUM)
– and across a broad spectrum of tech-
nical disciplines – invested considera-
ble time and energy to develop the final
programme.
In April 1998 a Coaltech 2020 Steer-
ing Committee was formed under the
chairmanship of a senior industry exec-
utive to guide the planning process. In
that year alone, 10 Steering Committee
meetings were held.
A one day workshop was also held at
Eskom with nearly 50 participants. The
workshop focuses on a wide spectrum of problems facing the coal industry in this country. The organisa-
tions involved were Amcoal, Chamber of Mines, CSIR, DME, Duiker, Eskom, NRF/THRIP, Ingwe, Iscor, NUM,
Wits and Pretoria University.
The workshop also grouped the research needs into seven technology projects and 95 new research top-
ics or needs were identified. It developed the Coaltech 2020 Programme Framework which was then refined
at various subsequent meetings and workshops.
Seven separate technology projects were initially identified. The technology project on Saleable Product
was subsequently combined into Coal Processing and this project was renamed Coal Processing and Dis-
tribution.
The six final technology projects included:
- Geology and geophysics
- Underground mining
- Surface mining
- Coal processing
- Coal distribution
- Surface environment mining
- Human and social aspects
However, it was recognised by the steering committee that further workshops were needed to determine
the objectives, outputs, milestones, cost and duration of each research task identified.
The second series of technology project workshops were then carried out at the CSIR Miningtek between
27 August and 3 September 1998. A total of 87 coal industry experts from mines, mining groups, labour

unions, the DME, universities and research agencies participated and nearly 850 man hours were spent at
the workshops in generating the outputs detailed in this document.
The result was the formulation of a comprehensive research programme, consisting of 90 research tasks.
At the beginning of November 1998 the Coaltech 2020 business plan was prepared. It was presented to the
various coal mining houses and stakeholders at the end of November 1998 with the ﬁnal decision to estab-
lish the research programme made in December of that year.
On 1 April 1999 the programme ofﬁcially came into being. It represented the culmination of 12 months of
planning and work by the steering committees, industry representatives and other interested parties. Impor-
tant to note is that its establishment was a milestone in coal mining research in this country.
human resources and students
There are two requirements for the Coaltech 2020 programme to be a success: the technical problems
must be solved by research and the coal mines must become more receptive to the results of research.
To achieve both these objectives implies much more postgraduate research that focus on those areas that
make up the Coaltech programme.
From 1999 to 2008, 59 degrees were completed. This included 12 PhDs and 27 Masters degrees, of which
11 were awarded to previously disadvantaged individuals and 19 to women
a change
In 2007 Coaltech 2020 underwent some changes. It became a research association incorporated under
Section 21 of the Companies Act, 1973. It also relocated to the Chamber of Mines building. Its programme
manager, Johan Beukes, moved with the programme.
Today the Coaltech Shareholders are: Anglo Coal, Xstrata Coal, Eskom, Exxaro Coal, Sasol Mining, BHP
Billiton Energy Coal South Africa, Total Coal, the CSIR, the Chamber of Mines, Bon Terra Mining, Kuyasa
Mining, Kangra Mining, Leeuw Mining with Wits, UP, NRF, labour (NUM) and the DME.
The programme has gone from strength to strength since this change, with big established coal compa-

nies renewing their membership or coming on board. The programme also created a class of associates
for smaller companies interested in particular aspects of Coaltech 2020’s research, but not in all areas. The
companies are able to join the research areas relevant to them within Coaltech 2020. In this way the pro-
gramme has seen a plethora of companies joining.
celebrating 10 years
During the past 10 years, the programme has completed more that 100 research projects.
The Coaltech stakeholders have benefited from the leverage generated by pooling resources and from the
experiences that collaborative research can harness. The value of Coaltech is that competing companies
are able to sit around a table and share information.
There are five factors which make this research programme unique to the coal mining industry:
It is truly collaborative: collaborative between mining houses and Eskom, labour, and the state, as well
as collaborative between the universities and the various research and funding organisations;
It is driven by industry needs;
It provides for a formal involvement of students and partnerships with centres of tertiary education;
The proposed funding arrangement requires industry to contribute a third of the funds needed, while the
balance is funded by various state organisations.
It involves a voluntary tripartite partnership between business, the state and labour.
The Coal mining industry has shown that companies competing with each other can work together in
knowledge development. Coaltech 2020 has evolved over the past 10 years and shown that it is adaptable.
Its chairperson, Dick Kruger, is confident it will continue for another decade.
‘The strength of Coaltech 2020 is that the people using the knowledge are the people who oversee its de-
velopment. The thrusts are drawn from mine personnel. They define the problem and work closely with the
researcher and supervise them. As a result, knowledge transfer has never been a problem. It has resulted in
a sense of ownership by the coal companies from the top to the bottom levels.’
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research highlights
introduction
T
he Waterberg Coalfield (Figure 1) in the Limpopo Province contains vast resources of coal and is the
next area that will supply South Africa with energy well into the future. The coalfield is in the Karoo-
age Ellisras Basin. Coaltech Research Association commissioned an airborne geophysical survey
of the area (Figure 2), to better understand the structure of the basin. Methods applied were the magnetic
method and the radiometric method. The datasets collected were:
• Magnetics (Figure 3)
• Total count radiometrics (Figure 4)
• Uranium count radiometrics (Figure 5)
• Thorium count radiometric (Figure 6)
• Potassium count radiometrics (Figure 7), and
• Digital Elevation Model (DTM) (Figure 8)
The magnetic susceptibility in the Ellisras
Basin is low; however, the application of a
phase operator on this data (Figure 9) re-
veals a large amount of weakly magnetised
anomalies that could be due to pre-Karoo
features in the basin floor. The radiometric
data complemented the magnetic data by
delineating the basin boundaries and indi-
cated large block faulting.
importance of the study
There is currently only one mine in the
Waterberg Coalfield (GrooteGeluk) and is
the sole supplier to Matimba Power Station.
Medupi Power Station – which is of similar
size – is currently under construction in the
same area and will also source its coal from
Grootegeluk, which may cause delivery ca-
pacity problems.
The Waterberg Coalfield is highly faulted
and all the structures and their effects have
not been identified and studied to date. Pre-
cise locations of the faults and structures
geology & geophysics
waterberg coalfield airborne geophysics

will greatly impact on the estimation of both the shallow and deep coal resources, by removing some of the
uncertainty regarding the coal resources.
geological setting
The coal-bearing rocks belong to the Karoo Supergroup and was deposited between 260 and 190Ma ago.
It formed as a large graben structure bounded by basin edge faults:
In the north, on older basin rocks (Melinda Fault zone) that belong to the Limpopo Mobile belt.
In the south, with the Waterberg Group (Eenzaamheid and Ellisras Faults).
Post Karoo faults (Daarby Fault) that disrupt coal seams.
The formation of the basin was controlled by structures that were formed and reactivated over time (Daar-
by Fault) and is the basis for the block faulting that occur throughout the basin.
stratigraphy
The area covered by the geophysical investigation consists mainly of three types of geological terrains:
The Limpopo Mobile Belt – highly metamorphosed gneiss which is 2700Ma (Kramer et.al, 2006).
The Ellisras Basin – consisting of the Waterberg Group (Barker et. al, 2006) and the Karoo Supergroup
(Johnson et. al, 2006b) – contains the coal, of which most is in the Grootegeluk Formation (110m thick in
the south).
Recent cover is from the weathering of gneiss of the Limpopo Mobile Belt, the Karoo rock in the north and
from Waterberg sandstone in the south.
Intrusive rocks – the most important of these rocks are those that cut through the coal-bearing rocks and
disrupt the seams. They occur less frequently in the Ellisras Basin.
geophysical survey
The survey was conducted in 2007 and covered eight 1:50 000 sheets. The survey was ﬂown in a N-S
direction at a 200m line spacing. The ﬂying height was 80m at a speed of 230km/h. The sampling frequency
was 10Hz, which implies a measurement every 6.5m. The magnetic data was collected with a caesium va-
pour magnetometer (resolution 100pT). The radiometric data was collected with 80 litre NaI crystal and the
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elevation was measured using a laser altimeter.
The contact between the Limpopo Mobile belt and the Ellisras Basin can easily be seen on the magnetic
data (Figure 3). It also shows the absence of strongly magnetised structures in the basin.
The total count radiometric data (Figure 4) shows the northern contact of the Ellisras Basin clearly and the
large block faulting. It also shows radioactive material eroding from the source (Waterberg sandstones) in
the south into the sediment load of the north-flowing Mokolo River. These sandstones are mainly the Feld-
spar-enriched Kranskop Sandstones, which indicate that the original source was granitic in composition.
The source in the north is the gneiss of the Limpopo Mobile Belt.
The uranium count (Figure 5) and the thorium count (Figure 6) show a similar pattern. The higher thorium
count suggests that the source of the radioactivity is much older; i.e. the current source is a second genera-
tion source.
The potassium count (Figure 7) is the highest and maps the distribution of the radioactive isotope of feld-
spar.
geophysical interpretation
figure 7: waterberg potassium data figure 8: waterberg dtm data
figure 4: waterberg total count data
figure 5: waterberg uranium data figure 6: waterberg thorium data
figure 3: waterberg magnetic data

The enhanced phasemag data (Figure 9) show all the smaller anomalies in the magnetic data. This con-
firms the idea that the structure in the Ellisras Basin is either weakly magnetic, or all structure is below the
Karoo cover in the basement material (Waterberg).
Fieldwork indicated that dyke outcrops are scarce and highly weathered. The complete dataset was used
to do a lineament interpretation (Figure 10). All interpreted dykes and faults were indicated.
A surface geology interpretation was done by using a ternary radiometric image (Figure 11). It was calcu-
lated by using potassium count in the ‘red channel’, total count in the ‘green channel’ and uranium count
in the ‘blue channel’. The interpreted surface geology is shown in Figure 12. The major interpreted block
faulting is shown in figure 13.
figure 9: phasemag data figure 10: lineament interpretation
figure 11: ternary image of the waterberg coalfield figure 12: surface geology interpretation
figure 13: interpreted block entities

physical properties
To do a credible geophysical interpretation and modelling, it is always necessary to sample the geology and
measure the physical properties of the different lithologies. Samples were taken of the Karoo Lavas (Letaba Ba-
salt), Karoo sandstones (Molteno Formation) and Waterberg sandstones (Kranskop, Holkrans and Mogolakwena
formations) (Figure 14).
A specimen was taken from what we first believed was a hyrdrothermal or felsitic dyke (Figure 15). Microscope
studies showed that it is an iron rich pisolite with growth rings around a quartz nucleus. This means that origin
was not hydrothermal, but hygroscopic.
The physical properties show that the basalts and shales are magnetic and conductive. The sandstones are
mostly non-magnetic. Densities of the shales and sandstones vary.
Using this data, profiles were modelled that indicated that the Waterberg is a half-graben structure (Figure 16).
conclusions
The airborne geophysical survey was a major contribution towards the knowledge of the Ellisras Basin. The
data and the first interpretation have shown that the basin has undergone much more structural disturbance than
what was previously suspected. The survey also showed a large amount of previously unknown structure in the
basin.
This poses the question; how many of these structures remain undetected because they are non-magnetic in
nature? The question can most likely be satisfactorily answered by an airborne electromagnetic survey. It will
produce much more additional data that will help us understand the structure of the Ellisras Basin better. This will
ensure better coal delineation and ultimately better mining practises with a better coal recovery.
figure 14: geology formations of the waterberg coalfield figure 15: pisolite structure discovered in the waterberg coalfield
figure 16: model of the waterberg basin

compilation of a textbook: a guide for using
geophysics on the south african coal fields
This project aims to produce a comprehensive guide for coal geologists on the principles, application,
strengths, weaknesses and pitfalls of all geophysical techniques that have been used, or might be applicable
on the South African coal fields.
The book will cover the following topics:
Introduction to South African coal mining and exploration;
The physical properties of coal: a discussion of the petrographic composition of coal and surrounding rock
types and how this relates to physical properties;
Introduction to the geophysical techniques applicable to coal, including magnetics, gravity, electromag-
netics, electrical methods, borehole methods, airborne geophysics, seismics, wireline logging and satellite
imagery;
Description of different techniques and the underlying principles;
Overview of the application of geophysics to coal internationally: a historic overview and recent develop-
ments;
Summary of coal problems and possible geophysics solutions – problem scenarios to be discussed in-
clude cavity/old workings detection, depth of weathering detection, dyke and sill detection, pollution plume
mapping, dolomitic pinnacle mapping, coal thickness left in floor/roof of mines, mapping coal underneath
pans, coal quality, geotechnical analysis of boreholes, SPONCOM and underground fires;
Potential future technologies, including in-seam radar, roof profiler, ERT streamer for wetlands coal map-
ping, chirp for wetlands coal mapping and acoustics for seam thickness mapping.
The book will also include a collation of existing physical properties and information on useful resources;
for example, a listing of geophysical service providers and internet resources.
The publication of this book is expected to have a number of key impacts in the areas of safety, health,
environment and economy; for example: It will increase the awareness of the role that geophysics could
play in characterising hazardous geological anomalies and other subsurface hazards, including near-surface
cavities, underground fires, hazardous roof conditions, pollution plumes etc. The successful (and more ef-
fective) application of geophysics could contribute to more cost effective mining.
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T
he recent increase in the demand for thermal coal required by Eskom for electricity generation, has
prompted the coal industry to review the technologies and techniques available for processing low
grade coals in order to produce thermal coal. In the past, power stations were mostly supplied with
a relatively high-grade of raw coal from a small number of captive mines. Presently, coal is supplied from
many different sources by a variety of large and small companies. Some of the coal potentially available for
combustion by Eskom is of a low grade and has to be
beneficiated to remove stone, shale and pyrite prior
to use.
It is necessary to find new technologies that can be
used to remove the contaminants from the raw coal – a
process referred to as ‘de-stoning’. A suitable process
should be able to handle large tonnages, be inexpen-
sive to install and operate and must still be able to de-
liver the required quality of coal. In South Africa, water
is a scarce resource and the optimal use of water dur-
ing coal processing is a further concern that has to be
taken into consideration.
Coaltech has embarked on a process to review and
evaluate available technologies for the beneficiation of
low-grade raw coals and discards. Current dense-me-
dium processes, wet jigging, dry jigging or dry shaking
tables as well as optical sorting technologies are be-
ing evaluated as part of the process.
Although dry processing is generally less efficient
than the conventional wet processing technologies,
it does offer several advantages. Firstly, no water is
consumed, which is a very important consideration for
mining operations in South Africa and in particular for
the Waterberg coalfield. Secondly, pollution of streams
is eliminated since no slurry is produced. A third important consideration is the fact that the moisture content
of the product coal remains low, which ensures that the heat value of the coal is maximized.
Coaltech is therefore looking specifically at the potential of dry beneficiation techniques in the South Af-
coal processing
dry processing of coal
figure 1: sorter at mintek
figure 2: FGX in operation at NBC

rican context. Three potential dry-processing technolo-
gies are available, namely optical sorting, dry jigging
and dry dense-medium beneficiation. Optical sorting
tests are being conducted in co-operation with Mintek,
whilst dry air jigging is being evaluated in cooperation
with both Exxaro and Xantium. At present, tests are be-
ing conducted on pilot-scale FGX air-table units capa-
ble of processing 10 tons of raw coal per hour. Xantium
is busy with the construction of a full-scale FGX plant
and testing will also be done on this plant in the near fu-
ture. The optical sorting machine at Mintek is shown in
Figure 1. Figure 2 shows the Exxaro pilot FGX air table is
in operation at NBC Mine near Belfast. The Xantium test
unit, in operation at Palesa Mine, is shown in Figure 3.
dry screening of coal
During the dry beneficiation of coal, it is usually required to pre-screen the raw coal at a relatively small
screen aperture, typically 6 mm, in order to remove the finer coal prior to beneficiation of the coarse coal. It
is also viable in many cases to remove the -6 mm coal
from the feed coal to a dense-medium or wet-jigging
plant. Keeping the fine coal dry, maximizes the heat
value of the coal and improves the efficiency of the op-
eration.
It is thus required to dry-screen raw coal that is not
always completely dry. Dry screening of coal at small
screen aperture sizes is very problematic when the coal
contains more than about 5% moisture. This is often
the case in practice, since water is routinely used dur-
ing mining operations to control dust emissions. During
rainy weather, the problem becomes worse.
Tests conducted with a pilot-scale Bivi-TEC screen,
as well as on a full-scale screen in production at New
Clydesdale Colliery, have thus far given encouraging results, but further research is still required. The Bivi-
TEC screen in operation at New Clydesdale is shown in Figure 4.
dry dense medium separation
A technology that is new to South Africa (but report-
edly already in limited commercial use in China), is dry
fluidised-bed dense-medium separation. This process
offers all the advantages of dry processing plus good
separation efficiencies.
A preliminary Coaltech sponsored study into dry
dense-medium separation at the University of Kwa-Zulu
Natal (UKZN), yielded encouraging results and the study
has now been expanded to include the University of the
Witwatersrand. The laboratory-scale dry dense medium
separator constructed at UKZN is shown in Figure 5.
figure 4: Bivi-TEC screen at New Clydesdale Colliery
figure 3: FGX in operation at Palesa Mine
figure 5: Laboratory scale dry dense medium drum

This task has been at the very forefront of Coaltech’s Engineering steering committee’s activities since 2004.
Very little has – deliberately – been published in the public domain. The time has come to change this. A little
background information on the considerations leading up to the establishment of this project is probably in
order first.
S
outh African coal demand is soaring, with an increasing need to extract coal under worsening min-
ing conditions from dwindling fossil fuel reserves. Although national estimates vary significantly, the
minimum percentage of unminable coal reserves is estimated at more than 20%. There are many
reasons why perfectly combustible coal is not mined, chief of which are stone boulders buried within the
seam (called ‘floating stone’), layers of various thickness stone sheet (called ‘lenses’) or because the floor
or roof – or both – pinch off access to coal behind them over such a distance as to make it uneconomical
to mine through. These stone formations easily damage highly productive mechanised mining machinery
that is specifically designed to deal with coal. Even at a very conservative national reserve estimate of only
30 billion tons of minable coal, there is a significant amount of coal (i.e. 6 billion tons or more) that can be
liberated if the associated stone can be effectively mined through.
Coaltech’s engineering steering committee’s chief goal is to develop effective measures to reduce the
overall capital cost of mining per ton of coal removed. One way would be to directly influence the cost of
equipment ownership and another is to increase the yield from existing infrastructure and resources by liber-
ating more useable coal for the same cost expenditure. The current Vibrant Roadheader project is squarely
aimed at both these approaches.
There is also an opportunity around national priorities – such as new job creation and poverty alleviation
– by helping smaller mining groups (of which many are BEE partners) in their choice of potential low cost,
high value mining equipment suitable for replacing drill and blast coal mining operations, and by stimulating
entrepreneurial activities such as local after sales support system creation.
In South African coal mining the unfortunate situation has developed where very expensive mining equip-
ment has to be used in applications they were not designed for. Currently there is no rock cutting technology
that can compete in terms of reliability with drill and blast stone work mining. Drill and blast mining often
damage the stability of the rock strata, which increases the cost of support and safe mining.
The advent of a vibration technology cutting head could just change this situation. The vibration technol-
ogy superimposes a high frequency impact motion on top of the normal rotational motion of a cutting pick,
much in the same way as impact is used when drilling with a masonry drill bit into concrete. And because
the Chinese machinery is so competitively priced, it makes them extremely attractive and deserving of seri-
ous consideration.
In 2005/6, Coaltech tested the first vibration technology roadheader (ELMB-75C) in a South African coal
mine, with limited success. The primary objective of the test was to determine the ability of the vibration
technology to improve the cutting ability of the cutting head in various stone formations. The primary limita-
tion identified was that the vibration technology cutting forces could not be made to bear upon the targeted
engineering
the search for a more cost-effective stone cutting
machine

rock types due to insufficient stiffness provided by the roadheader embodiment. As a result, it could not be
determined if the fundamentals of the vibration technology were sound. After much deliberation and lobby-
ing for funding, Coaltech members decided to order a much heavier and stiffer embodiment to re-test the
vibration technology cutting head.
After
significant
flame proof
modification and the
adaptation to accept both the
75 kW and 120 kW cutting booms
at a leading coal mine workshop,
the new Vibrant Roadheader machine
was delivered to a South African coal mine for
follow-on testing in March 2009. The original objective – evaluation of the vibration technology – has been
expanded to include the testing of a more powerful non-vibrating cutting head in the same stone work
conditions, to get some idea as to what the base potential might be should a much more powerful cutting
head also be activated or vibrated (the latest news from China is that a 132 kW vibrating head has just been
unveiled). Apart from these considerations, the tests now also include operational cost and production data,
where possible.
The new machine is based on a standard 120 kW roadheader from China, which doubles the mass of the
frame attached to the vibration technology cutting head and boom. Significant changes were also made to
the hydraulic circuit, which, combined with the larger, heavier embodiment, also helps with the stiffness.
The second vibrating head cutting test has just ended and the detailed data analysis has only just begun.
Although it is too early to publish any conclusive results yet, a great deal was learned.
The new machine was first tested on a remnant full coal face section, where the operators could learn to
master the machine with little risk of damaging it. Further, since the machine had to be reassembled with
very little assembly documentation, any start-up problems could be addressed too.
After cutting in coal for three weeks, the machined moved to a new face where 30% of the face consisted
of a 70 to 80 MPa siltstone formation at the floor parting.
After a short period of operation it became evident that the fitment of a vibrating cutting head to a body not
originally designed for vibration, caused all kinds of problems, like bolts and other fittings vibrating loose,
causing significant delays. Through dogged determination and perpetual vigilance over an extended period
of time, these vibration related failures were systematically rectified, until the machine’s reliability improved
to such an extent that meaningful testing could commence.
Testing procedures and methodology had to be changed and tweaked continuously, but in the end enough
data was collected to be able to compare the vibrating versus non-vibrating mode performance of the 75
kW cutting head with respect to advance rates. Long term phenomenon, such as the effect of vibration on
a possible increase in tonnes mined per pick, could not be determined, though results obtained seem to
figure 1: The new EBZ-120MN Roadheader fitted with the ELMB-75C cutting boom

point in this direction.
During the trial it became apparent that, although the mass of the machine was increased by almost 100%,
it was still not enough and that the bearable cutting force was also insufficient. Both these factors made it
impossible to fully engage the cutting head into the stone, and the maximum cutting loading achieved was
less than 50% of the available power (for both the 75 kW and 120 kW heads). By changing the testing meth-
od and by increasing the hydraulic pressure by 40% during the latter part of the 120 kW cutting head trial
phase, results were obtained that confirmed the potential of the machine. The 120 kW non-vibrating cutting
head consequently yielded surprisingly good increases in advance rates, which surpassed the performance
observed from the 75 kW cutting head. Time constraints prevented further testing of the 75 kW cutting head
with this increase in supply pressure, though comparable increases in performance can be expected.
During the trial the opportunity presented itself to thermally analyse the cutting operations and gather a
figure 2: the coal test-face figure 3: the first stone face, 30 % stone (near floor)
figure 4: a large floating stone on the first panel, with another view for scale
figure 5: the second stone face, dissected by two very hard sand stone lenses (one shown right)

whole new set of data. Of primary interest were the thermal images identifying maximum spark temperatures
while cutting sandstone in the roof. Perhaps surprisingly, a preliminary review of the captured data suggests
that thermal temperatures are not nearly as high as the brightness of some sparks might seem to suggest.
For the last two weeks of the trial, a third 70/30 stone face (the majority siltstone – again dissected by two
very hard sandstone lenses) was used for testing the 120 kW cutting head. During this period there wasn’t
a single stoppage due to the unreliability of the machine. This is a testament to the dedication, commitment
and resourcefulness of the support personnel in bringing the machine to this point of reliability and to the
base potential of this specific embodiment.
The detailed draft trial report should be ready for comment by the engineering steering committee by early
September 2009. After the trial report has been finalised, the engineering steering committee will make a
recommendation to the Coaltech board on the way forward.
figure 6: minor body modification and repair work (spinner drive motor came loose 3 times)
figure 7: a view of the 75 kW cutting head in action Figure 8: a thermal image of the picks directly after cutting
sandstone in the roof
figure 9: the largest piece of slab-stone conveyed through the machine – 5 x 0.45 x 0.12 m

surface environment
brine treatment and disposal
introduction
T
he aim of this Coaltech funded research is to develop a methodology/technology in which coal mine
waters and brines can be pre-treated, beneficiated or concentrated.
There are three components to this project. Firstly, the screening of coal mine waters and brines
for their concentration profile, pH, speciation, cation and anion balance, absorption capacity and equilibrium
analysis. Secondly, an investigation of the removal of the minor and trace elements such that the waste water
stream is simplified to ensure more effective downstream progressing (UWC). The third part of the project
looks at further downstream processing where the removal of the major elements from the processed waste
stream is considered. This part is further divided into two sections – the Eutectic Freeze Crystallization (UCT)
technologies and the use of counter current ion exchange (CPUT). The approaches to achieve these objec-
tives have been as follows:
1. Screening of coal mine waters and brines (UWC)
Screening of brines for their concentration profile, pH, speciation, cation and anion balance, absorp-
tion capacity and equilibrium analysis
2. Problem element removal from brines (UWC)
Optimisation of the synthesis condition of zeolite Na-P1 from Arnot fly
Determination of Cation Exchange Capacity (CEC) and % toxic element removal from brine with
zeolite Na-P1
Removal of sulphate from circumneutral mine water
Adsorption of toxic elements from brine with natural clays and zeolites
The synthesis of immobilised crown ether ligands for selective removal of Cr and other toxic species
from brine effluents
The synthesis of highly selective mesoporous sorbents for mercury removal
Functionalized Polyacrylonitrile (PAN) fibres containing amidoxime groups for metal ion adsorption
from brine
Electrodeionization for removal of major and trace elements from brine
3. Removal of the major elements
Eutectic Freeze Crystallization (UCT)
Sequential removal of pure salts operating under eutectic freeze crystallization conditions and within
the metastable zone width
Ion Exchange Treatment (CPUT)
B.Tech mini projects
Counter current ion exchange (CCIX) and membrane processes for recovery of major elements from
brine
•
•
•
•
•
•
•
•
•
•
•
•
•
•

1. screening of coal mine waters and brines
The evolution of brine water streams during industrial processing, at Tutuka Power Station and Secunda
industrial complex for instance, was investigated as an example in order to understand the variability in
process brines, as well as what effect each stage in the industrial process might have upon the brine water
quality. The sequence of the brine evolution during water treatment stages at Tutuka Power Station is shown
in Figure 1. Figure 2 shows the composition of brine at each stage in the process in comparison to the intake
water feed where cooling and mine waters are mixed.
figure 1: sequence of the water treatment stages at Tutuka Power Station.
legend for figure 1
TP108 cooling water: mine water mixture at clarifier outlet (ca. 1:9)
TP208 mine water (New Denmark)
TP308 cooling water/mine water mixture (after microfiltration, acidifying and chlorine addition)
TP408 RO Brine
TP508 RO Permeate
TP608 brine after contact with ash
TP708 cooling water
TP808 feed for vapour compressor (combined RO brine)
TP908 vapour compressor reject (VC brine)
TP1008 vapour compressor product
figure 2: composition (% difference) of brine at each stage in the process in
comparison to the intake water feed where cooling and mine waters are mixed.

The samples taken from the different water treatment stages at Tutuka Power Station have similar chemi-
cal compositions because the water is evolving from one source (mixed mine water and process cooling
water). The difference in quality is in the concentration, namely the amount of ions, as they are added into
a stream (or removed) by the desalination processes. Mine water and the vapour compressor condensate
showed differences in composition from the general trends. Desalination by reverse osmosis and vapour
compression removes cations and anions to a large extent, except Si, Cr, Mn, Fe and Pb. The Na content in
the vapour compression reject brine increased by 2237.1%, Mg by 1894.4% and Ca by 1930% in relation
to the starting water (TP108 - mine water mixture at the clarifier outlet).
Samples from Sasol Synfuels Complex in Secunda generally had similar compositions The RO brine from
Sasol-Secunda is more concentrated than that from Tutuka Power Station, but brines from both sites can be
classified as a Na-SO4
water type. Analysis of Piper diagrams showed all the data points lay in a single line,
meaning that the samples are mixtures of one another. This follows from the fact that effluents are recycled
at these sites.
PHREEQC, Aq.QA and Visual MINTEQ speciation models were used to calculate the saturation indices of
discharge streams from desalination activities at Tutuka Power Station and Sasol Synfuels Complex in Se-
cunda. The saturation indices of all the minerals predicted were found to be between -10 and 25, except for
results obtained from non-converging calculations of four samples from Sasol Synfuels Complex (modelled
using PHREEQC). The calcium concentration was much higher in some brine samples which had been in
contact with fly ash at Secunda. These samples had convergence problems during modelling with PHREE-
QC. The program fails when non-carbonate alkalinity is greater than the specified total alkalinity as the
program tries to calculate total carbonate species such that carbonate alkalinity + non-carbonate alkalinity
= total alkalinity. The study findings show that saturation indices for calcite and aragonite (from converging
calculations) done using Aq.QA and PHREEQC models were comparable.
Middelburg mine waters – as well as many other mine waters – are rich in calcium and magnesium concen-
trations and the pH of these waters is near to neutral. Fluid properties obtained using the Rockware Aq.QA
software shows that Middleburg and Navigation mine waters are of Mg-SO4
2
- and Fe-SO4
2
- types respec-
tively. The sulphate concentration in these waters varies between 4500 ppm to 5000 ppm.
Modelling showed that most brine streams, including mine water, were likely to precipitate minerals such
as calcite and aragonite because of the brines being supersaturated with respect to these mineral phases.
This leads to scale build up in facility piping and equipment used to handle these water streams.
2. problem element removal from brines
The synthesis of pure phase zeolite Na-P1 product from flyash was optimised by using a factorial designed
study of the many synthesis variables. Zeolite NaP1 was successfully prepared from Hendrina and Duvha
fly ash after the ideal conditions for synthesis – when using Arnot fly ash – were identified and applied. The
purest phase zeolite Na-P1was obtained from Arnot fly ash when ageing was performed at 47 °C for 48
hours and the optimum water content was at a molar ratio of 1 SiO2
; 0.42 Al2
O3
; 0.06 NaOH ; 0.49 H2
O in
the hydrothermal step, while optimum crystallisation occurred at 140 °C after 48 hours. A small pore zeolite,
hydroxysodalite was produced when using brine – instead of pure water – as a solvent in the hydrothermal
synthesis process together with Arnot, Hendrina and Duhva ash.
The Cation Exchange Capacity (CEC) of the zeolite product improved to more than 4 meq/g by optimisa-
tion during synthesis, when changes were made to the the ageing conditions and the water content used
(Figure 3).
Larger quantities of toxic elements could be removed from Emahlahleni brines when a zeolite NaP1 prod-
uct was prepared using fly ash (FA) (Figure 4). Removing toxic elements from Emalahleni brine was most
effective when the optimized zeolite Na-P1 prepared from Arnot fly ash was used, and most of the toxic ele-
ments present in brine (Pb, Cd, Ni, Mn,V, As, B, Fe, Se, Mo, Sr, Ba) were significantly reduced. Moreover, the

zeolites showed a significant reuse capacity and could selectively remove the toxic elements from a highly
complex, high salt brine matrix.
Eskom have committed themselves to fund both the scale-up of the synthesis of zeolite Na-P1
from fly ash
to small (400 ml) pilot scale stirred reactors, and the technoeconomic study of preparing zeolites from ash
at a larger pilot scale.
Experiments were conducted to reduce sulphate levels in circumneutral mine waters – such as mine water
found at Navigation and Middleberg mines – by treating these effluents with fly ash (FA). These waters are
sulphate rich, containing sulphate levels of above 4000 ppm, but are not acidic and is therefore a dilute form
of brine. For instance, Hendrina mine water has very low levels of Mn, Na and K ~30 ppm, Ca ~500 ppm and
850 ppm of Mg but contains high sulphate levels. In our study we successfully treated circumneutral mine
water with FA and removed sulphates to the saturation point of gypsum. Removal was pH dependant and
the maximum pHs attained were 10.13, 11.77, 12.12 and 12.31 for minewater to FA ratios 5:1, 4:1, 3:1 and
2:1 respectively. For a 5:1 ratio of minewater to FA, 54.92% sulphate removal was observed while for 2:1 ra-
tio 71.06% sulphate removal was achieved. At pH > 9, Mn(OH)2
starts to precipitate from the circumneutral
water and was completely removed from the mine water.
Thus, treating mine water with FA to pH 12 results in 70% sulphate removal. Treating mine water with FA
and adding Al(OH)3
resulted in 95% removal of sulphates, while the final concentration of sulphates was 213
ppm, below the DWAF effluent limit of 500 ppm. The optimum amount of Al(OH)3
to be added was 0.0844 g
per 100 ml of mine water. This is a significant finding.
The best sulphate removal was achieved when seeding with gypsum crystals followed by the addition
of Al(OH)3
at high pH, further precipitating out sulphates. Initial results on optimisation show that the proc-
figure 3: cation exchange capacity as a function of water content during preparation of zeolite
Na-P1
figure 4: toxic element removal from Emalahleni brine with optimized zeolite Na-P1 prepared from
Arnot fly ash

ess can be improved by enhancing the degree of ettringite precipitation as a way to remove the maximum
amount of sulphates.
Circumneutral mine water (CMW), mixed with highly contaminated acid mine drainage (AMD) in different
ratios, could also be treated with fly ash (Table 1) and removal of sulphate to above 90% was achieved after
short contact times, without further addition of any chemicals or seeds or Al(OH)3
.
INITIAL concentration FINAL concentration
pH SO4
2-
(ppm) pH SO4
2-
(ppm) % removal
AMD 2.4 42862 – – –
CMW 6.5 4623 12.35 1191 74.24
*mixture 1:1 2.56 20870 10.16 1842 91.17
*mixture 2:1 2.65 17142 12.69 1228 92.84
*mixture 3:1 2.63 15797 12.66 1236 92.76
table 1: FA treatment for sulphate removal from CMW blended with AMD
(*CMW to AMD ratio (and the ratio of the mixtures to FA is 2:1)
Trace levels of B, Cr and Mo seeps into the water from the ash treatment to above the required effluent
limit, but B and Mo levels can be reduced in the process water by using zeolites synthesized from FA.
Cr removal is also being investigated. Low cost material – such as fly ash –, natural clays – such as cal-
cium and sodium bentonite clay –, attapulgite clay and natural zeolites – such as clinoptilolite – are being
studied. Clay particles can adsorb anions, cations, non-ionic and polar contaminants from natural water or
contaminated water. Clinoptilolite have CEC values between 100 and 400 meq 100 g−1). Adsorption studies
are in progress.
The selective extraction of Cr6+
, As5+
, Sr2+
, Cd2+
, and Hg2+
and U is possible using highly selective crown-
based ligands immobilised on porous SiO2 support surfaces. We have successfully immobilised the 18-
crown-6 on silica-gel (60Å) and the results were confirmed by solid state NMR as well as FT-IR. After the
initial trials of the immobilization, a whole series of immobilized 18-crown-6 were prepared for the extraction
of various toxic elements from water. We are still awaiting results of the % toxic element removal obtained
with these materials.
The mercury (Hg2+
) levels in the sampled mine waters have been found to be higher than the DWAF re-
quirement. Therefore, we are investigating the use of high surface area mesoporous silica and their carbon
analogues for highly selective mercury removal. A high surface area carbonaceous material possessing sur-
face oxide groups has been successfully synthesized via a CVD process using a silica template. The surface
properties of these new materials are currently under investigation with model dye molecules and will then
be applied for Hg removal.
The research on Ion Exchange Fibres is ongoing. Advantages of fibres as adsorbents include a relatively
high osmotic stability allowing for multiple drying and moistening of the filaments, as well as an overall in-
crease in surface area which promotes faster particle diffusion. We are confirming the repeatability of the
amoxidime functionalised polyacrylonitrile fibres and also assessing their ability to remove some trace ele-
ments from mine waters in addition to the Ca2+
and Mg2+
already successfully evaluated. Uptake of the alkali
/alkaline earth metals was good and also independent of pH, thus amidoxime functionalised fibres did not
exhibit any preferential affinity for Ca, Mg, Na. The adsorption kinetics were found to be sufficiently rapid
reaching equilibrium in 15 minutes. The advantage of the fibrous configuration of the polymer backbone is

the faster rate of equilibrium compared to resin beads.
Research on electrodeionisation is actively being persued after a research visit by Dr L Petrik to 3 laborato-
ries in Turkey during June 2009 – sponsored by the NRF – which included a visit to Prof Nalan Kabay at Ege
University in Izmir where collaborations in electrodeionisation were finalised. Dr Kabay has vast experience
in functionalised ion exchange fibres. Dr Nuran Boke, a post doctoral fellow from Ege University, has arrived
at UWC and started her year of post doctoral studies with ENS and is recommissioning the electrodeioniza-
tion system at present.
B. eutectic freeze crystallisation
During 2009, the Crystallisation and Precipitation Unit, Department of Chemical Engineering at the Uni-
versity of Cape Town, continued to make significant advances in the novel research area of Eutectic Freeze
Crystallization (EFC) for the treatment of hyper-saline brines. This research, under the guidance of Prof Ali-
son Lewis and Dr Jeetan Nathoo, is at the stage of scale-up from laboratory glass reactors to a 2L stainless
steel reactor – a scraped cool-wall reactor that has been designed to conduct both batch and continuous
experiments. This reactor has been constructed and the commissioning phase is due for completion in June
2009. The coolant Kryo 45 – used as the heat transfer liquid with a temperature range of -45ºC to 30ºC in
place of methanol – has proved successful and will continued to be used. The Ph.D proposal of Mr Dyllon
Randall – ‘Sequential Removal Of Pure Salts Operating Under Eutectic Freeze Crystallization Conditions
And Within The Metastable Zone Width’ – was accepted by the selection committee for an upgrade from an
M.Sc. Mr Randall will be travelling to the Netherlands from June to work on the EFC with experts at the TU
Delft as part of human capacity development.
Various aspects of the Coaltech funded research project – which included investigating the effect of an-
tiscalants on key EFC operating and performance parameters and sequential salt removal – have contrib-
uted to the broader research thrust aimed at demonstrating proof of concept for EFC as a feasible treatment
for multi-component hypersaline brines. Some of the key findings included:
figure 5: eutectic freeze crystalisation
figure 6: eutectic freeze crystalisation

The sequential removal of individual salts from a multi-component brine stream can be achieved through
strategic seeding. The seeded experiments also showed good reproducibility, demonstrating better con-
trol of the crystallizing system.
For a ternary Na2
SO4
MgSO4
H2
O system, a salt purity of 95% was obtained after only two washes.
Based on the preliminary results of the single antiscalant tested at the typical concentrations used in
industry, no significant negative effects on the key EFC operating and performance were observed.
Also in 2009, a prototype scraped stainless steel 2.5L eutectic freeze crystalliser with automated tempera-
ture and torque control with online data capturing capability was commissioned.
The construction of a state of the art low temperature laboratory – the Industrial Crystallization Eutectic
Laboratory (ICELab) – was completed and commissioned at UCT. The ability to carry out experiments in a
climate-controlled environment at temperatures down to -20˚C, significantly enhances the research capabil-
ity of the unit.
Coaltech continues to play a key role as a benefactor in developing the fundamental and applied knowl-
edge base for ultimately implementing this novel EFC technology for the treatment of hypersaline brines in
the broader context of South African mining and processing industries, and industry partners are looking at
specific solutions using this technology.
Aspects of the various research findings have already been or are in the process of being communicated
to both industry and the scientific community through media such as research reports to Coaltech, journal
publications and oral presentations at local and international conferences such as the SAIMM 2009 and
the International Mine Water Conference. From a capacity building perspective, 4 postgraduate students
continue to be actively involved in this project with one of the students successfully upgrading his MSc to
a PhD.
c. ion exchange treatment
Over the past year several BTECH Chemical Engineering miniprojects were completed at CPUT, focussing
on removing major elements from brine solutions.
Carbonation of a fixed bed of Amberlite IRA-67 resin for sodium carbonate production from sodium chlo-
ride brines was investigated. CO2
reacts with the resin, followed by the loading or ion exchange step when
the concentrated brine solution is passed through the bed, resulting in the precipitation of sodium bicarbo-
nate. The solubility of NaHCO3
in water is 9.6 g/100 g of water and the solubility of NaCl in water is 36g/100g
of water at 20 °C. The concentration of the brine solution must be high in order for the sodium bicarbonate
to precipitate. The resin is regenerated back to its free base form by using a strong base NaOH solution.
In practice, calcium hydroxide will be used as regenerant. Sodium carbonate would be recovered from the
ion exchange effluent by subsequent heating and evaporation of the solution. An exothermic reaction takes
place when the free-base resin is reacted with CO2
causing a temperature rise in the bed. If there is too high
a temperature rise in the column, it will lead to the deterioration of the resin which decreases the capacity
of the plant and will lead to down time because of the regeneration step. The temperature profile in the ion
exchange column was determined axially and radially. The highest temperature increases were obtained for
the radial configuration compared to the axial configuration. Further work is in progress to convert the NaCl
to NaHCO3
.
A comparative study was done using a commercial zeolite, Faujasite, and a natural zeolite, clinoptilolite, to
determine which adsorbent was effective at removing both Mg2+
and Ba2+
from a simulated brine solution.
•
•
•

The percentage removal for Mg2+
and Ba2+
were determined to be 13% and 18% respectively when com-
mercial Faujasite was used, and when natural clinoptilolite was used the % removal increased to 21% and
30% for Mg2+
and Ba2+
respectively. These results showed that the low cost natural zeolite, clinoptilolite, per-
formed better in terms of removing Mg2+
and Ba2+
from the simulated brine than an expensive commercial
zeolite. These low cost adsorbents could be utilised to remove toxic metals from mining effluents – currently
being evaluated at UWC.
Electrodialysis (ED) is well known in water treatment and has the following advantages which make it feasi-
ble for industrial use: no chemical additives required, no extensive pretreatment, the ability to simultaneously
separate a wide variety of ionic constituents and high recovery of demineralised water. A three compartment
electrodialysis cell was built. Synthetic brine (5% NaCl) was used as the central compartment solution; this
was the solution that was to be desalted. A 17 g/L Na2
SO4
solution was used as the electrode rinse. Both the
centre compartment and electrode rinse solutions were recirculated back to their respective tanks. After 17
hours the electrical conductivity of the 5g/L brine had been reduced from 9.11 to 0.33 ms/cm. The electrical
conductivity had been reduced by 96 % indicating a good NaCl removal. It was thus possible to remove 96
% of the NaCl from the brine. The electrode rinse solution concentration also decreased from 17 to 2 g/L
Na2
SO4
. Commercial ED cells would be efficient in desalinating the brine but the cost factor and the water
recovery should not be ignored.
Ion exchangers are available as the familiar beads (“resins”) and also as very fine fibres. Advantages of fi-
bres include a relatively high osmotic stability allowing for multiple drying and moistening of the filaments as
well as an overall increase in surface area which promotes faster particle diffusion. Fibres have applications
in ion exchange operations where they will be used to desalinate or purify brines resulting from the mining
of coal and other processes. The pressure drop-flow rate relationship for fluid flow through porous fibrous
media using Darcy’s equation was established at CPUT. Non-woven and woven fibrous material (a semi-
commercial product: FIBAN and an experimental polyacrylonitrile functionalized fibre) were evaluated. The
FIBAN AK-22-1 offered more fluid resistance, implying a greater pressure drop across the material exposed
to the flow of water. This can be attributed to a smaller void volume when compared to the polyacrylonitrile
woven type of material. The non-woven fabric also had a thicker cross section when compared to the woven
type which would result in greater viscous losses due to the thickness of the material being larger and the
fluid having to travel a greater distance across the bed. This results in a greater resistance to fluid flow. The
polyacrylonitrile material appeared to have a greater porosity than the woven type due a larger superficial
velocity existing during compaction of the material when the fluid passed over it. The linear relationship was
clearly illustrated when pressure drop was plotted against flow rates. The polyacrylonitrile material had the
larger permeability of the two materials investigated. The greater pressure drop results in increased cost
expectations due to an increase in energy required to create the required fluid flow across the material. If
the method would be applied commercially, it would be necessary to take costs into consideration and in
that instance the material with the least fluid resistance (lowest pressure drop) would be recommended.
However, tests need to be performed, evaluating the flow of saline solutions across either bed in order to
simulate the treatment of brines.
The work on the Counter Current ion Exchange CCIX, by Mr Bruce Hendry and students at CPUT, has
been dormant since his presentation to Coaltech in March 2009 as the students are completing their theo-
retical course work prior to starting their projects later this year. They are available for research projects
from July 2009 again. The ideal would be to move the current CCIX rig at CPUT to an industrial site and this
will be pursued for possible installation at the Koeberg Power Station. Condensate polishing plant or the
demineralisation plant, where plant chemists could conduct routine monitoring, maintenance and sampling.
However, an additional budget allocation would be required to effect the installation.

T
his study, carried out between July 2008 and March 2009, was a collaborative research project be-
tween the CSIR and Tshwane University of Technology, focusing on the removal of SO4
2-
from acid
mine drainage using the CSIR patented alkali barium and calcium (ABC) process. One of the envis-
aged benefits of using this technology is that the resultant sludges can be recycled to be reused as raw
materials in the process (e.g. BaCO3
). In addition, the final effluent can be used as grey water or treated to
drinking water standards without generating brines.
This study focused mainly on the SO4
2-
removal stage of the ABC process. The SO4
2-
removal process
involves precipitation of SO4
2-
present in water as CaSO4
to generate BaSO4
/CaCO3
sludge as shown in
equation 1.
Ca2+
(aq) + SO4
2-
(aq) + BaCO3
(s) -> BaSO4
(s) + CaCO3
(s) (1)
From Figure 1 it can be seen that the kinetics of SO4
2-
removal is faster when using excess synthetic
BaCO3
. In this regard, SO4
2-
removal to levels lower than 200 mg/l is achieved in less than 1 hr using molar
ratios of [Ba2+
]:[SO4
2-
] higher than 1.
From Figure 2, the use of commercial (China) BaCO3
for SO4
2-
removal exhibits much slower kinetics com-
pared to using synthetic BaCO3
(Figure 3). In this case SO4
2-
was removed to below 200 mg/l in about 2 hours
when a high dosage of commercial BaCO3
was added to 1000 mg/l SO4
2-
feed water in the [Ba2+
]:[SO4
2-
]
molar ratio of 1.8. This indicates that a longer retention at higher dosage of commercial BaCO3
would be
evaluation of the BaCo3
process for sulphate
removal on the coal mines acid mine drainage (AMD)
figure 1: effect of synthetic BaCO3-
concentration on the level of SO4
2-
removal in synthetic feed water

required for SO4
2-
removal rate comparable to the under dosed laboratory synthesized BaCO3
.
Figure 3 clearly illustrates the significant difference between synthetic and commercial BaCO3
on SO4
2-
removal from synthetic feed water. This difference in the rate of SO4
2-
removal between the two products
may be attributed to the different physico-chemical properties of the two products which still need to be
confirmed by further studies.
Figure 4 shows that the rate of SO4
2-
removal from synthetic feed water increased significantly at low pH
with SO4
2-
removed to levels below 500 mg/l after 1 hr. BaCO3
is sparingly soluble in water with a ksp value
of 5.1 10-9. The precipitation of SO4
2-
as BaSO4
requires that Ba2+
should dissociate from BaCO3
to be able
to react with SO4
2-
. The dissociation of BaCO3
in an aqueous solution is pH dependent. In this regard under
equilibrium conditions the laws of mass action indicates that more BaCO3
would dissociate at low pH and
figure 2: effect of commercial (China) BaCO3
concentration on the level of SO4
2-
removal in synthetic feed water
figure 3: comparison of SO4
2-
removal from synthetic feed water using a 1:1 molar ratio [Ba2+
]:[SO4
2-
] syn-
thetic and commercial BaCO3

become available for SO4
2-
removal. Thus as given in Figure 4 better SO4
2-
removal occurs at pH 7.89 com-
pared to pH 12.30.
An important step in the BaCO3
process for SO4
2-
removal is the recovery and recycling of BaCO3
. BaCO3
may be recycled from the BaSO4
sludge formed during the SO4
2+
removal step. This is achieved via two
stages;
(1) High temperature thermal reduction of sludge to generate water soluble BaS (2) H2
S stripping us-
ing CO2
to precipitate BaCO3
Figure 5 shows the results for electrical conductivity (EC) and sulphide during precipitation of BaCO3
from
a BaS feed solution via H2
S stripping using CO2
. EC gives a measure of ions present in the BaS feed solu-
tion. Figure 5 shows that the EC decreases gradually from 50 000 S/cm to almost zero over 3 hr of H2
S
stripping. Similarly, the sulphide content drops from about 6000 mg/l to almost zero over the same period.
The gradual drop in EC during H2
S stripping is an indication of the precipitation of BaCO3
from Ba(OH)2
and
Ba(HS)2
formed on BaS dissolution in an aqueous medium.
ﬁgure 4: the effect of pH on the rate of SO4
2-
removal from pre-treated AMD
ﬁgure 5: electrical conductivity and sulphide content data during BaCO3
precipitation

T
he different aspects of spontaneous combustion, or sponcom for short, have featured on Coaltech’s
R&D agenda right from the start in 1999. During 2008/09, the fight against sponcom has continued
and although the magic bullet was unfortunately not found, several developments point towards a
slow but steady increase in the knowledge and skills required to eliminate sponcom one day from our op-
erations.
The Sponcom Guidelines, on which the University of the Witwatersrand has been working since 2007,
were unfortunately not finished during the period due to personnel problems at the University. Publication of
the guidelines remains a priority for the coming year.
Hot hole blasting, reported on elsewhere in this text, was strongly driven by the committee.
During the year a number of meetings were sought or held with technology providers which the committee
thought could contribute to the objectives of combating sponcom. This culminated in a workshop, organ-
ised jointly by Coaltech, Anglo Coal and the Fossil Fuel Foundation, on the 24th
of July, in which some of
these initiatives were presented to industry representatives and further discussed and developed.
The focal point of the workshop involved a presentation and discussion from a United States-based com-
pany with an international solution to coal mine fires. Known as CAFSCO, the company manufactures
compressed air foam systems that have proven successful in extinguishing sponcom fires under a variety
of circumstances. While traditionally used water-based foams degrade in hours, CAFSCO produces air and
nitrogen foams with chemical stabilisers and infused with micro-organisms. As a result, this foam remains
stable for several days, while the micro-organisms consume all oxygen in the surrounding atmosphere,
thereby preventing the flow of oxygen to the combustible material.
Moving forward, CoalTech will be investing in a proof of concept review and trials into this technology.
Other topics raised at the workshop included an overview of a mine’s own experiences with sponcom,
while Christophe Roelofse of Spectra Flight Aviation Services discussed a cost-effective geo-referenced
thermal imaging survey technique used for sponcom identification and characterisation. Robbie Louw of
Promethium Carbon concluded the workshop with a talk on the mitigation of SponCom as an ideal means
to earn carbon credits through the Kyoto Protocol’s Clean Development Mechanism.
surface mining
spontaneous combustion

O
ne of the negative consequences of sponcom is that it affects blasting of overburden and coal
seams negatively. Because one cannot exactly know what is happening at the bottom of a blast
hole, it may be that these holes are positioned close to the seat of heating, or intersect a crack
which is connected to a source of heating, or any other myriad of mechanisms transferring heat from spon-
com to the blast hole. The result in all cases is a blast hole with an elevated temperature, and should defer
one to charge such holes with explosives. Premature ignition of such holes has occurred sporadically in the
past few years, fortunately without causing any serious injury. In response, the industry has, in conjunc-
tion with the explosives manufacturers, developed a number of procedures aimed at reducing the risk of
premature ignition. Of the principal approaches, one is based on eliminating the most sensitive links of the
initiating system (detonators and primers) from the bottom of the
blast holes, and the other on monitoring the temperature of the
borehole and only charging it under rigorous prescribed condi-
tions.
However, these procedures cannot by themselves prevent pre-
mature ignitions, as there are too many unknown variables in the
blasting sequence. Some of these have to do with the lack of
knowledge of the behaviour of explosives and accessories un-
der conditions of elevated temperature and pressure; others with
the lack of understanding of what happens in the borehole be-
tween the moment that it has been charged and the moment that
it is initiated. Coaltech has set out to investigate these aspects
in order to improve the safety and efficiency of blasting under sponcom conditions.
To this end, Coaltech has sought the assistance of the explosives manufacturers active in the South African
market, two of which have risen to the challenge and are cooper-
ating in finding solutions for this pressing problem. They are Afri-
can Explosives Limited (AEL) and Bulk Mining Explosives (BME),
which have joined forces in exploring alternative technologies.
One avenue of research is to develop, or make available, a
range of explosive products and accessories with improved heat
resistance. The challenge is not so much in the chemical formu-
lation of such explosives – this field has apparently been widely
researched- as to develop and apply testing protocols that can
unambiguously and universally quantify the degree of heat re-
sistance such explosives and accessories may afford. In this re-
spect, the investigation currently focusses on identifying differ-
ent testing protocols and on a monitoring campaign to measure
temperature and pressure at different elevations in charged blast holes.
Another avenue is the development of an early warning system that alerts the blasting crew when the
temperature in one or more blast holes has exceeds pre-set temperature limits, allowing the blasting crew
to take the necessary measures in time. Tests have been conducted with several versions of the device with
audio alarms and further development of the technology continues, which is expected to lead to commer-
cialisation of the technology.
blasting of shot holes heated by sponcom
figure 2: version 3 in field trial
figure 1: hot Eye Version 3

The ﬁnal draft of this report will be available from 31 July 2009.
T
he focus of the study has been to identify and address shortfalls in the management of the social
aspects of mine closure in South Africa, with a view to provide a pragmatic social process guide for
use by closure practitioners.
As an initial step, the key principles for mine closure contained in the local and international literature were
examined, in order to extract generic principles for stakeholder behaviour related to closure. Environmental
issues are presented only in as far as they contribute to socio-economic stability and/or development. The
relationships between the different stakeholders – especially host communities and the mining corporations
– lie at the heart of the problem.
Following this, two South African coal mines in the last stages of operational life – or where closures had
recently taken place – were investigated. The case studies undertaken involved a mine in a major coal
mining region which was closed in 2002 and subsequently re-opened, and another in a remote part of the
country which is destined for closure in 2014. A third case study was intended at the commencement of this
project, but afterwards investigation proved not to be feasible.
Both international and local data was assessed, and through the use of leading-edge sociological theories
guidance for closure was developed for local, pragmatic application. This guidance includes issues such as
stakeholder capacitation, engagement, and partnering, with the ultimate aim of leaving communities with
opportunities to perpetuate their existence, with the necessary responsibilities of all stakeholders known,
understood and agreed to.
project team and contributors
Ms Julie Stacey, CSMI Associate
Dr Annelie Naude, CSMI Associate
Prof May Hermanus, CSMI Director
Prof Phillip Frankel, CSMI Associate
human & social aspects
the socio-economic aspects of mine closure and
sustainable development
centre for sustainability in mining and industry, university of the witwatersrand

The outcome of closure has been shown to be dependent on (i) the mine’s investment in time, money and
energy in dealing with social disruptions engendered by closure and (ii) the response of the community. Mine
closure outcomes can be described as minimalist, compliant and sustainable.
minimalist closure compliance closure
The minimum required, such that after closure :
Job opportunities have been created that are
sustainable
Skills development has equipped people to par-
ticipate in economic activity on a sustainable
basis
Local infrastructure has been developed to serv-
ice social and economic needs sustainably
Social investment projects and employee wel-
fare caters effectively to human needs well into
the future
•
•
•
•
Mining company complies with the regulatory regime,
whether or not the regulatory framework facilitates
optimal social closure and sustainable development.
In South Africa (the most explicit of all Southern Af-
rican countries in articulating policies and targets for
social and community development), this includes
compliance with:
The Mining and Petroleum Resources Act
(2002)
The Mineral and Petroleum Resources Develop-
ment Regulations (2004)
Various supportive legislation and regulatory
provisions related to, inter alia, procurement of
services, employment equity, skills development
and training
Local and regional developmental mechanisms
– the IDP process
The Mining Charter: Broad-Based Socio-Eco-
nomic Empowerment Charter for the South Af-
rican Mining Industry(2005)
•
•
•
•
•
sustainable closure
Internationally, sustainable closure process can demonstrate:
Ethical business practices:
Fundamental human rights and respect for different values, cultures and customs;
Valid data and sound science:
Continual improvement in health, safety and environmental performance:
Biodiversity and integrated land-use planning:
The social, economic and institutional development and long-term viability of communities:
That oppression and inequality is tackled in a purposeful, continuous, comprehensive and action-oriented
manner (Twelvetrees, 1991).
In the local context, sustainable closure processes also:
Require that closure is not “simply” skilling people or providing jobs, but provides for long term economic
diversification
Reflect concrete social realities rather than vague and standard prescriptions
Align indigenous South African social conditions with international best-practice
Represent site specific frameworks and strategies derived from systematic developmental research, that are
usable on a micro-managerial, step-by-step sequential or concurrent basis, and
Are deployable on a rehabilitative basis, in cases where closure turns out to be unsustainable
•
•
•
•
•
•
•
•
•
•
•
•

problem definition
C
urrently it is estimated that approximately 50 million tons of coal is transported by road, predomi-
nantly in the Witbank, Middleburg and Bethal areas of Southern Mpumalanga. Due to the large vol-
umes, the resultant road damage problems associated with transport and rising costs puts the coal
industry under increasing pressure to find viable and sustainable alternative modes of coal transportation.
1.
transportation
road damage
figure 1: typical road damage caused by coal trucks

The aforementioned scenario is further complicated in that current coal reserves are nearing depletion. It is
envisaged that new coal reserves will be unlocked from other areas within South Africa, including the Water-
berg area, some 400km away from the current mining activity. Furthermore, these new reserves would have
to be transported to, amongst others, the Southern Mpumalanga area to sustain the production of several
power stations, as well as export terminals such as Richards Bay.
In this light, Coaltech requested an independent coal transport study to identify alternative transport modes
and technologies, with the aim of determining which technologies are best suited for specific transport re-
quirements. These transport requirements may vary according to the lead distance, terrain, throughput
requirements and geographical location, to name but a few factors. It is the intention of the study to provide
guidance in terms of selecting the most appropriate technology that would best satisfy these requirements
in a cost effective and safe manner, while minimising any negative socio-economic impacts.
objectives
The objective of this project is to produce a study on alternative coal transport modes that could be
employed by the coal industry, so that the following needs are fulfilled:
Provide the Chamber of Mines’ Colliery Committee with information to support their policy decisions
with respect to various coal transport modes;
To test the feasibility and applicability of suggested transport modes at various distances;
To highlight transport modes that may require further research and investigation.
project scope
The project scope takes into consideration the problem definition and objectives of the study, which will
be delivered by 30 September 2009. In essence, a high level desktop study and primary research is to be
conducted, subject to the following scope inclusions and exclusions:
3.1 scope inclusions
The following aspects with respect to the study are included in the scope of this project:
Conducting desktop and primary research into alternative transport options, their characteristics, ad-
vantages, disadvantages, costs and socio-economic impacts;
Investigating the applicability and feasibility of each coal transport mode suggested;
Comparing the identified transport options against the same evaluation criteria;
The production of an interim report to be reviewed by the Coaltech Technical Committee;
The production of a final bound report containing the findings of the study.
3.2. scope exclusions
The project is intended to provide an independent high level view, and specific scope exclusions are as
follows:
Determining the best transport option for specific applications in mind;
The investigation into the optimisation of the current coal transport network;
The recommendation of specific infrastructural investments.
2.
1.
2.
3.
4.
3.
•
•
•
•
•
•
•
•
•
•

research deliverables
The physical deliverables for the project includes the following:
The production and submission of an interim research report to be reviewed by the Coaltech Technical
Committee;
The production and submission of a final bound research report containing the findings of the study, to
be approved by Coaltech.
The content of the final research report will focus on addressing the following requirements:
To provide a list of all available coal transport options;
To provide an indication of the feasibility and applicability of each transport option at various distanc-
es.
To highlight novel transport options that might need further research and investigation;
To provide a completed evaluation matrix that compares all the identified transport options against each
other, based on a set of predefined evaluation criteria.
research methodology
Coaltech employed the supply chain specialist company, Crickmay & Associates, to conduct this trans-
port investigation and supplied them with a list of companies, primarily Coaltech members, as points of
contact within the wider coal industry, to participate in and contribute to this initiative. The research was
divided into the following areas:
Task
No
Task Description Expected Result Deliverable
1
User Requirement Definition Coaltech meetings held and
agreed project approach finalised
Documented project approach
2
Initial Information Gathering Interviews with industry experts
completed
Minutes of meetings with industry
experts
Identification of initial transport
option list completed
Primary list of transport options
3
Desktop Research Primary desktop research com-
pleted
Desktop research notes
Identification of additional trans-
port options completed
Amended list of transport options
4
Primary Research Planning of interviews and sched-
uling of meetings completed
Minutes of meetings with industry
transport experts
Interviews with technology ex-
perts done
Primary research notes
5
Define Research Parameters Evaluation matrix developed Approved evaluation matrix
6
Research Evaluation Technology evaluation and report
development completed
Populated evaluation matrix
Project quality assurance Interim project report
7
Report approval, supplementary
research and report amendment
completed
Final research report
Project quality assurance done
table 4: research breakdown
4.
I.
II.
I.
II.
III.
IV.
5.

5.1. evaluation criteria
In order to accurately compare the potential of each transport mode, it is imperative that these technolo-
gies are evaluated against the same criteria. The following table provides a brief summary of the evaluation
categories:
No Category Description
1
Cost Capital Investment Cost
Operating Cost
Maintenance Cost
2
Capacity Capacity per Unit
Maximum Transport Capacity
Throughput Rate (hourly / daily)
Material/ Article Size Restrictions
Minimum / Optimum / Maximum Transport Distances
3
System Characteristics Advantages
Disadvantages
Optimum Operating Conditions
Geographical Layout Requirements / Terrain / Typography
4
Safety Impact Public Safety
Operator Safety
5
Healt Impact Public Health
Operator Health
6
Environmental Impact Environmental Impact / Damage
Possible Pollution
7
Social Impact Displacement of Settlements
Restriction of Movement
Prevention of Normal Lands Usage
8
Economic Impact Possible Job Creation Opportunities
Impact on Economy of the Area
9
Further Reasearch
Required
Current State of Technology
Fundamental Research
Testing / Pilot Applications
Estimated Research Cost and Duration
table 5: evaluation category summary

progress to date
The research is currently ongoing and the final comparisons and evaluations have not been completed,
although the following table presents a short summary on some of the technologies that have been identi-
fied and researched to date.
No Transport Mode Short Description
1
Aerial Ropeways A ropeway conveyor is essentially a subtype of cable car, from
which containers for goods, rather than passenger cars are sus-
pended.
2
Barges A barge is a flat-bottomed boat, built mainly for river and canal
transport of heavy goods.
3
Coal Log Pipelines (CLP) The CLP concept presses coal into the form of circular cylinders -
coal logs - so that coal can be transported by water flowing through
a single underground pipe.
4
Conventional Conveyor A conveyor system consists of mechanical handling equipment that
moves materials from one location to another, via a belt that moves
across rollers.
5
Deep Sea Shipping Ocean transport of coal via ships
6
Intermodal Freight Transport
Systems
Intermodal freight transport involves the transportation of freight in
an intermodal container or vehicle, using multiple modes of trans-
portation (rail, ship, and truck), without any handling of the freight
itself when changing modes.
7
Magnetic Levitation Systems The Mag-Lev Transport System uses magnetic levitation technology
that allows noncontact, frictionless conveyance of a levitated body
within a dedicated transit corridor. The mag-lev technology utilises
two types of permanent magnets coupled with an electronic posi-
tion control system to achieve noncontact levitation.
8
Merry-Go-Round Trains (MGR) A merry-go-round train (MGR) is a block train of hopper wagons
which both loads and unloads its cargo while moving.
9
Performance Based Standard
(PBS) Vehicles
Performance Based Standards (PBS) brings a different approach
to vehicle regulation. It focuses on how the vehicle behaves on the
road, rather than how big and heavy (length and mass) it is, through
a set of safety and infrastructure protection standards. In other
words, PBS governs what a vehicle can do, not what it should look
like. In the context of this report, PBS vehicles operate on public
roads, but they generally carry much larger payloads than conven-
tional vehicles.
10
Pipe Conveyors Pipe conveyors are similar to conventional conveyors, but the belt is
rolled to form a closed pipe. Because of this closed pipe shape, the
transportation is dust free and the material is protected from envi-
ronmental influences. This system is ideal for large inclines, as well
as routes with multiple bends.
11
Rail Rail transport is the conveyance of goods by means of wheeled
vehicles running along railway lines.
12
Rail-Veyor Rail-Veyor moves materials, using a light rail track system with
a series of two-wheeled, inter-connected cars that typify a long,
open trough moving along the track. Individual cars are loaded and
offloaded while moving, by turning the track upside down like a roll-
ercoaster, which allows the load to be tipped by gravity. The system
is designed to operate automatically, without a driver, via a control
room.
6.
table 6: summary of technologies

No Transport Mode Short Description
13
Road The transportation of material by truck, through a network of
public roads. Typically used where haul distances and ship-
ment sizes are small.
14
Road Trains A road train is a trucking concept used in remote areas - it
consists of a conventional tractor unit, but instead of pulling
one trailer or semi-trailer, the road train pulls two or more of
them, thus resulting in a substantially larger payload. Road
trains in the context of this report run on privately owned
roads
15
Rope Conveyor (RopeCon) RopeCon long-distance, continuous conveyor system, suit-
able for the transportation of bulk materials and unit loads of
any kind, via a suspended cable system.
16
Slurry Pipelines A slurry pipeline is used to transport coal, where crushed
coal is mixed with water and mixed into a slurry and then
pumped over a long distance through a pipeline. At the end
of the pipeline, the material is separated from the slurry in a
filter press to remove the water. Water is usually subject to
a waste treatment process before disposal or return to the
original station.
17
Tube Freight Transportation Systems Tube freight transportation is a class of unmanned transpor-
tation systems in which close-fitting capsules, or trains of
capsules, carry freight through tubes between terminals. The
system is either pneumatically powered or it uses capsules
that are electrically powered, running in a tube about two
meters in diameter. The system can be thought of as a small
unmanned train in a tube carrying containerised cargo.
The following pictures and photographs show identified systems in operation:
figure 2: pipe conveyor

conclusion
Although this transport investigation is not completed yet, it is becoming increasingly clear that there is
no single transport technology that could cost effectively satisfy all the divergent transport requirements,
across all distances, for all coal sizes and across all types of terrains. The optimum coal transport solution
lies in the effective combination of all the available technologies into an integrated and well managed net-
work, where individual technologies are applied in applications where it is best suited.
This approach allows for the safest and most cost effective transport application between each source
and destination, with the lowest socio-economic impact, while protecting and enhancing the available trans-
port infrastructure. The question remains, which technology for which application?
Coaltech is eagerly awaiting the successful completion of this research project, with the expectation that
these questions will be answered.
7.
figure 3: coal road train figure 4: aerial ropeway
figure 5: rail-veyor
figure 6: conventional road and rail transport

alleviation of compaction
investigating the alleviation effect of different grass species root development on
compacted rehabilitated soil

ϭ͘ WĂŶŝĐƵŵ ŵĂǆŝŵƵŵ ;'ƵŝŶĞĂ ŐƌĂƐƐͿ
Ϯ͘ ŚůŽƌŝƐ ŐĂǇĂŶĂ ;ZŚŽĚĞƐ ŐƌĂƐƐͿ
ϯ͘ ŝŐŝƚĂƌŝĂ ĞƌŝĂŶƚŚĂ ;^ŵƵƚƐǀŝŶŐĞƌ ŐƌĂƐƐͿ
ϰ͘ ŶƚŚĞƉŚŽƌĂ ƉƵďĞƐĐĞŶƐ ;tŽŽů ŐƌĂƐƐͿ
ϱ͘ WĂƐƉĂůƵŵ ŶŽƚĂƚƵŵ ; ĂŚŝĂ ŐƌĂƐƐͿ
ϲ͘ &ĞƐƚƵĐĂ ĂƌƵŶĚŝŶĂĐĞĂ ;dĂůů ĨĞƐĐƵĞͿ
ϳ͘ ĂĐƚǇůŝƐ ŐůŽŵĞƌĂƚĂ ; ŽĐŬƐĨŽŽƚͿ
ϴ͘ sĞƚŝǀĞƌŝĂ ǌŝǌĂŶŝŽŝĚĞƐ ;sĞƚŝǀĞƌ ŐƌĂƐƐͿ
ϵ͘ ĞŶĐŚƌƵƐ ĐŝůŝĂƌŝƐ ; ůƵĞ ďƵĨĨĂůŽ ŐƌĂƐƐͿ
ϭϬ͘ WĞŶŶŝƐĞƚƵŵ ƉƵƌƉƵƌĞƵŵ ; ĂŶĂ ŐƌĂƐƐͿ
ϭϭ͘ DĞĚŝĐĂŐŽ ƐĂƚŝǀĂ ;>ƵĐĞƌŶĞͿ
ϭϮ͘ /ƐĐŚĂĞŵƵŵ ĨĂƐĐŝĐƵůĂƚƵŵ ;,ŝƉƉŽ ŐƌĂƐƐͿ
ϭϯ͘ dƌŝĨŽůŝƵŵ ƉƌĞƚĞŶƐĞ ;ZĞĚ ĐůŽǀĞƌͿ
ϭϰ͘ ƌĂŐƌŽƐƚŝƐ ĐƵƌǀƵůĂ ;tĞĞƉŝŶŐ ůŽǀĞ ŐƌĂƐƐͿ
ϭϱ͘ ǇŶŽĚŽŶ ĚĂĐƚǇůŽŶ ; ŽƵĐŚ ŐƌĂƐƐͿ
ϭϲ͘ WĞŶŶŝƐĞƚƵŵ ĐůĂŶĚĞƐƚŝŶƵŵ ;<ŝŬƵǇƵͿ
the following is a list of species being evaluated

the inﬂuence of different mechanical soil disturbance techniques and incorporation
of organic matter on compaction alleviation

animal production on irrigated rehabilitated land

Figure 16: Exclosures used to do pasture evaluation while excluding the animal

Figure 19: Germination studies conducted using water with different levels of
salinity water
evaluate the scope of gypsiferous mine water on the germination and establishment
of other pasture species, to be selected for animal production under the irrigation
pivot system

conclusion

pobox61809,marshalltown21075hollardstreetIstﬂoor,chamberofminesbuildingjohannesburg2001
tel:0114987652fax:0865024842cell:0824621235email:coaltech@bullion.org.zawebsite:www.coaltech.co.za

annual report - 2008-9

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