FOSTERING THE USE OF CLEAN COALTECHNOLOGIES

The CARNOT Programme

EUROPEANCOMMISSION

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FOSTERING THE USE OFCLEAN COAL TECHNOLOGIES

The CARNOT Programme

EuropeanCommission

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The views expressed in this publication have not been adopted or in anyway approved by the Commission and should not be relied upon as astatement of the Commission’s views.

A great deal of additional information on the European Union is available on the internet.It can be accessed through the Europa server (http://europa.eu.int).

Cataloguing data can be found at the end of this publication.

Luxembourg: Office for Official Publications of the European Communities, 2001.

ISBN 92-828-8874-6

© European Communities, 2001Reproduction is authorised provided the source is acknowledged.

Cover illustration:Combined heat and power station Altbach, Germany. Courtesy of Babcock Borsig Power.

Printed in Belgium

PRINTED ON WHITE CHLORINE-FREE PAPER

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urope’s energy strategy in the new millennium must focus primarily on managing thegrowing dependence on energy in the context of sustainable development. Security of

supply has taken on a new urgency with the recent volatility of oil prices and is likely to bestrongly affected by wider developments in energy markets, including liberalisation and

environmental developments.

To develop a strategy which can reconcile security of supply with other objectives which include theenlargement of the European Union,the functioning of the internal energy market and action tocombat climate change, the European Commission presented a Green Paper on this subject inNovember 2000. The intention was to launch a debate on the options available to limit the risksbetween all actors concerned at political level,in industry and also in society.

We should keep the coal option open because of the abundance and diversity of resources, andbecause it is easily available and cost-competitive. In addition, coal has a stabilising effect on energymarkets:it played a leading role in solving previous oil crises and remains available as a substitutionfuel. Coal can contribute to security of supply while also considering climate change, providedadvanced clean coal technology is sufficiently developed and implemented. European industry, withthe support of several Community programmes, has made crucial advances in reducing pollutantemissions;all efforts are now focused on CO2 abatement. Accordingly, research,development anddeployment of clean coal technology are fundamental for the future contribution of coal to securityin energy supply.

The contribution of solid fuels to European energy supply will increase with the enlargement process,particularly in relation to electricity production. Both indigenous and imported solid fuels shouldcontribute to the variety of fuel mixes for competitive and environment-friendly power generation.

The promotion of existing and commercially available cleaner solid fuel technologies worldwide willnot only enhance the sustainability of the European Union’s industries based on energy but alsoensure that third countries can be aware of those technologies which will be a benefit to and enablethem to contribute significantly to the objectives of the Kyoto Protocol.

Information on the cleaner use of solid fuels is especially important, since we are aware that manycountries will continue to use this cheap source of energy. This booklet demonstrates the way inwhich coal,through the whole chain from preparation to combustion, can help to contribute tosustainable development in vast parts of the world.

by the Vice President Loyola de Palacio del Valle-Lersundi

(relations with the European Parliament,Transport and Energy)

CLEAN COAL TERCHNOLOGIES

FOREWORD

32

ECentral Audiovisual Library, European Commission

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FOREWORD 3

INTRODUCTION 5

COAL,THE FUEL AND ITS RESERVES 8

PREPARATION AND TRANSPORTATION OF COAL 13

USES AND MARKETS FOR COAL 16

COAL AND THE ENVIRONMENT 19

COMBUSTION TECHNOLOGIES:THE HEAT MARKET 22

POWER GENERATION:CLEAN COAL TECHNOLOGIES 24

METALLURGICAL USE OF COAL 29

CONCLUSIONS AND OUTLOOK FOR SOLID FUELS IN THE EU 31

ABBREVIATIONS 32

CONTENTS

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ecurity of energy supplies is vital for oureconomies and our way of life. However,given the fluctuation in the oil price, the

concentration of four fifths of the world’soil and gas resources in politically unstableregions, and the commitment to the KyotoProtocol, there are questions to be answered forthe future.

Coal is one pillar of energy worldwide. It repre-sents about one quarter of world primaryenergy consumption. The largest use of coal, byfar, is for the production of electricity. Worldwide,more coal is used in this market than any otherenergy source. Coal and lignite are used to fuelthe production of about 40 % of the world’selectricity; other uses include steel making andsteam raising. Most coal is used locally at thesite of production but about 15 % of productionis traded worldwide (oil – about 60 % and gas –about 20 %).

The abundance of coal, its location in ‘safe’areas of the world and the cheap cost of seatransport has enabled traded coal to becomeone of the most competitive energy sources inthe world.

The European Union can be viewed as havingbeen built on coal. The Treaty of Rome in 1952set up the European Coal and Steel Community(ECSC), a forerunner to the present Union.

Europe’s industrialisation was built on coal andalthough dependency on coal is now much less,the industries developed from these beginningsare still strong in Europe. Europe has about 40 %of the world market for energy and coal-relatedequipment and plants. The use of steam turbinesto turn heat into power owes much to theFrench scientist ‘Carnot’ – hence the name ofthis Energy programme.

The European Commission has been at theforefront of research, development anddemonstration into solid fuels use.

The European Commission promoted research,development, demonstration and disseminationof clean coal technologies through its variousprogrammes – ECSC coal R & D, JOULE, Thermie,the RTD frameworks and now Carnot. Much ofthis work is now commercial and is usedworldwide. European industries are the vehiclefor this exploitation.

‘Coal is a reliable, readily available, competitiveand environmentally sound source of energy’.

There is much market interest and benefit,including significant environmental advantagein European clean coal technologies beingutilised in developing countries were they havelow cost solid fuels.

CLEAN COAL TERCHNOLOGIES

INTRODUCTION

54

S

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The European Union is consuming more andmore energy and importing more and moreenergy products. If no measures are taken, in thenext 20 to 30 years, 70 % of the Union’s energyrequirement as opposed to the current 50 % willbe from imported products. As a result, externaldependence for energy is constantly increasing.This is also true in geopolitical terms, 45 % of oilimports are from the Middle East and 40 % ofnatural gas from Russia. The fact that the price ofcrude oil has tripled since March 1999 onceagain reveals the European Union’s structuralweakness regarding energy supply.

Against this background,The European Com-mission recently published its Green Paper‘Towards a European strategy for the security ofenergy supply’. This paper stresses the need forrational use of energy in reducing demand andfor a balance between and diversification of thevarious sources of supply (by product and bygeographical region).

Security of supply does not seek to maximiseenergy self-sufficiency or to minimise depend-ence, but aims to reduce the risk linked to suchdependence.

Environmental concerns are now shared by themajority of the public and are a problemcommon to all fossil fuels. The fall in electricityprices, as a consequence of the liberalisation ofthe energy market, goes against policies tocurtail increasing demand and to combatclimate change. The competition introduced intothe internal market is also changing theconditions of competitiveness for differentsources of energy supply (coal, nuclear, naturalgas, oil, renewables). The European Union willrebalance its supply policy in favour of ademand policy.

1.3 1.4 1.5 1.5

3.3

4.5

6.5

7.5

Industrialised countries

Developing countries

World population (billion) World energy consumption (billion tce)

Figure 1: World development of population and energy consumption

Source: UN 1999.

7.7

2.78.7

4.9

9.7

9.3

10.8

16.2

Industrialised countries

Developing countries

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Coal can address those objectives, reducingprimary energy consumption and saving energyresources through higher efficiencies andincreasing security of supply because coalsources are plentiful and spread over manycountries with stable political conditions.

The energy options for the European Union arestrongly influenced by the world context, the

new reference framework for the energy market,namely the liberalisation of the sector andenvironmental concerns. Furthermore, theenlargement of the European Union, up toperhaps 30 Member States with different energystructures, will affect the Union’s energy policy.

Potential new Member States like Poland andthe Czech Republic are strong coal countries!

76

INTRODUCTION

Other RES

Hydro

Nuclear

Gas

Oil

Coal

1.0660.2060.2471.8534.3202.724

1.5220.3240.9302.9484.946

3.042

1.8090.4161.4994.756

6.109

4.844

2.903

0.4974.561

6.729

6.529

5.916

1980 1998 2020 2050

World energy consumption (billion tce)

Figure 2: World energy consumption by fuel

Source: World Energy Council/IIASA, 1998.

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oal originally accumulated as material inswamps and peat bogs. Covered by siltand other sediments, and additionally

driven by movements in the earth’s crust(tectonic movements),these swamps and peatbogs often sank to great depths.

Coal is the alte red remains of pre h i s to r i cve g e t a t i o n .

With increasing depth the plant material wassubject to elevated temperatures and pressures.Over many millions of years, the continuingeffects of temperature and pressure caused

physical and chemical changes in thevegetation,transforming it into coal.

Initially, peat was converted into lignite or browncoal with low organic ‘maturity’. Over millions ofyears, additional changes progressively increas-ed the maturity and transformed the plantmaterial into the range of coals known as sub-bituminous. Further chemical and physicalchanges occurred until these coals becameharder and more mature at which point they areclassified as bituminous or hard coals. The pro-gressive increase in organic maturity continued,ultimately to form anthracitic coals.

COAL, THE FUEL AND ITSRESERVES

C

Figure 3:Schematic diagram: fossil fuels

Fossil fuels

Liquid and gaseous fuelsSolid fuels

Liquid fuels

Gaseous fuels

Coal (without lignite and others)

Lignite(and others)

Peat

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98

COAL,THE FUEL AND ITS RESERVES

50%

1% 49% 19% 31%

50%

Hard coal Low rank coal

Anthracite Bituminous Subbituminous Lignite

Metallurgicalcoking coal

Thermal steam coal

Carbon/energy content

Moisture content

Domestic/industrialincludingsmokeless

fuel

HIGH

HIGH

Maturity/age (some 400 million years)

PEATCOAL

Manufacturingof iron and steel

Power generationcement

manufactureindustrial uses

Mainlypower

generation

Somethermal

uses mainlyagricultural

Figure 4: Coal ages and maturity

The coals are classified by rank with pe at andl i g n i te being ‘l ow ra n k’ and ant h ra c i te ‘high ra n k .’

• Low rank coals, such as lignite and sub-bituminous coals, are characterised by highmoisture levels and a low carbon content, andhence a low energy content. They are typicallysofter, friable materials with a dull,earthyappearance.

• Higher rank coals are typically harder andstronger and often have a black vitreouslustre. Increasing rank is accompanied by arise in the carbon and energy contents anddecrease in the moisture content of the coal.

• Anthracite is at the top of the rank scale andhas a correspondingly higher carbon andenergy content and a lower level of moisture.

Coal reserves are, by far, the largest of all thefossil fuels but this is not mirrored by itspresent day use where oil is used to a muchgreater extent.

The world coal resources available for meetingour energy requirements today and in the futureare very extensive, compared in particular withmineral oil and natural gas.Viewed against thisbackground, the situation for coal supplies tomeet future world energy demand will presentno problem in the coming centuries.

Coal re s e rves are plentiful. Cu r re n t, coal re s e rve /p rod u ction ratios are five times those of oil andgas co m b i n e d.

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OPEC

othersEU-15

CIS

OIL202.4 billion tce

Figure 7: Economically minable reserves, 1998 oil and gas

OPEC

others

EU-15

CIS

GAS174.7 billion tce

Source: Oil and Gas Journal 1999

When it comes to quantifying the available worldcoal resources, the categories employed varyfrom country to country.

Recently, Germany’s Federal Institute of GeoSciences and Raw Materials made an attempt torecord the coal resources according to the

uniform quality parameter, ‘coal equivalent’ (ce),and to record quantities in the form of potentiallyavailable ‘resources’, including economically‘workable and recoverable reserves’. The figuresfound in this study match with a good degree ofaccuracy the figures displayed in the graph basedon data from the World Energy Council.

Coal68 %

Gas15 %

Oil17 %

World economic fossil fuel resources 1998

1177 billion tce

Figure 5: World economic fossil fuelresources

Figure 6: World fossil fuel consumption

Coal29 %

Oil44 %

Gas27 %

World economic fossil fuel consumption 1998

10.9 billion tce

Source: World Energy Council 1998, Oil and Gas Journal 1999

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Worldwide, coal resources were found to have atotal volume of 6 668 billion tce, with 1 160billion tce accounted for by lignites and 5 508billion tce accounted for by hard coals (includingsub-bituminous coal and anthracite). Of thistotal, some 799.8 billion tce are currentlyclassified as workable and recoverable, i.e. asactual reserves (lignites and hard coals).

One kilogram of coal equivalent is equivalent to an energy content (net calorific value) of7 000 kcal or 29 308 kJ.

Unlike the situation in oil and natural gas, theworld’s coal deposits have a wide geographicaldistribution with 96 % of the total reservevolume being concentrated in only 15 countries.Coal is available virtually everywhere withinrelatively short distances.

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CLEAN COAL TECHNOLOGIES

North America

CIS

China

Far East

Australia

Africa

EU-15

EEC

Central and South America

215.7

192.3

95.6

81.2

63.5

61.4

39.9

31.7

18.5

Figure 8: World coal reserves, economically minable (in billion tce)

North America

CIS

China

Far East

Australia

Africa

EU-15

EEC

Central and South America

956

315

1045

441

228

100

218

131

54

Figure 9: World coal production, 1998 (million tonnes)

Source: World Energy Council/IIASA, 1998.

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In 1999, the world output of hard coal totalled3 656 Mt, so that production in the previous 10years (1989–98) had risen by only 91 Mt or 2.5 %overall. By contrast, growth in the preceding decade(1979–88) had totalled 730 Mt or 26 %.The mainreasons for the slower growth are to be found inthe restructuring of the coal industries in Russia,eastern Europe and China. In spite of these mea-sures, these countries are still among the world’s10 biggest coal producers.These countries togetherwith the United States, India, South Africa, Australiaand Indonesia account for 92 % of world output.

Some of the EU applicant countries are majorcoal countries for example Poland and theCzech Republic.

Poland alone will more than double EU hardcoal production and lignite production will beincreased by some 60–70 %.

Coal is an available, low cost, easily utilised fuelwhich the world, especially in developingcountries, cannot ignore.

Co

al

Lig

nit

e

Co

al

Lig

nit

e

Austria

Finland

Spain

Ireland

Greece

France

United Kingdom

Germany

Others

Czech Republic

Poland

Figure 10: Coal production, EU-15 and EU applicant countries

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re p a ration is one of the links in the ‘co a lc h a i n’f rom mining to end-use. It enablesboth the non-coal seam mate rials and, to a

lesser exte nt, the inhere nt mate rials that aremined with the coal to be re m oved or part i a l l yre m oved – thus enabling coal to be used moree f f i c i e ntly with lower levels of emissions.

Coal pre p a ration is a key te c h n o l ogy for cleanercoal use.

Coal pre p a ration dates back beyond the mid-19thce nt u ry, when early methods co n s i s ted of co a ls c reening and hand selection to improve theq u a l i ty of coal for specific marke t s. Howeve r, it wa sin the early part of the 20th ce nt u ry, with the int ro-d u ction of mechanised mining, t h at the impo rt a n ceof coal pre p a ration be came fully re cog n i s e d. H i g h l yp rod u ct i ve mechanised mining can be ‘u n s e l e ct i ve’p roducing run-of-mine (ROM) co a l ,o ften with are l at i vely high and inco n s i s te nt mineral mat ter andm o i s t u re co nte nt, as well as diffe ring sizes ofp rod u ct (part i c u l a rly a high ‘f i n e s’ co nte nt ) .

Mechanised mining – a major adva n ce but morep roblems for coal pre p a ra t i o n .

Over the ye a r s, coal pre p a ration te c h n o l ogies haved eve l o ped to meet the challenge of diffe ring RO Mq u a l i ty while, at the same time, h aving to sat i s f yi n c reasingly stri n g e nt market re q u i re m e nt s. Nowa-d ays, coal pre p a ration is utilised, in va rying degre e s,by all the wo rl d’s major coal prod u ce r s. This ca ni nvo l ve a wide range of ope rations including rawcoal pre - t re at m e nt, coal sizing, be n e f i c i ation andd e wate ri n g, coal blending, tailings tre at m e nt andwater clari f i cat i o n , and coal blending.

Coal pre p a ration is now an adva n ced clean co a lte c h n o l ogy.

The traditional role of coal pre p a ration has be e none of improving the quality of coal to meet marke tre q u i re m e nt s, for example by reducing ash co nte ntand providing co rre ctly graded co a l . Howeve r, m o rere ce nt l y, it has been widely re cognised that co a lp re p a ration can also bring co n s i d e rable env i ro n-

m e ntal be n e f i t s.These benefits include re d u ce demissions of sulphur diox i d e, t h rough re m oval ofsome py ritic sulphur from co a l , and re d u ce demissions of ca r bon diox i d e, t h rough incre a s e de f f i c i e n cy of dow n s t ream coal utilisation plant .Other benefits include the re d u ced tra n s po rt at i o nre q u i re m e nt assoc i ated with low - g rade coal andre d u ced quantities of ash residues for dispo s a l .

Front-end cleaning via coal pre p a ration is a lowcost option to decrease emissions from coal use.

With these be n e f i t s, coal pre p a ration has nowe m e rged as an impo rt a nt clean coal te c h n o l ogy( CC T) ,p a rt i c u l a rly in developing coal eco n o m i e s,such as China and India, w h e re much of the coal is

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CLEAN COAL TECHNOLOGIES

PREPARATION ANDTRANSPORTATION OF COAL

P

Courtesy of RWE Rheinbraun

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still utilised in its raw unt re ated state. In theseco u nt ri e s, t h e re is a growing awa reness of the be n e-fits of improved quality and co n s i s te n cy of co a lsupply and one of the immediate pri o rities is toi n c rease the level of coal pre p a rat i o n . Fu rt h e rm o re,with global coal consumption pre d i cted to incre a s ein the future, l a rgely to meet the needs of thesed eveloping eco n o m i e s, t h e re will be a need for co a lp re p a ration te c h n o l ogies for many years to co m e.

Coal pre p a ration – a key low cost option forutilising coal in developing co u n t r i e s.

Eu ro pean companies have a long histo ry in thea p p l i cation of coal pre p a rat i o n ,d ating back beyo n dthe middle of the ninete e nth ce nt u ry. Th ro u g h o u tthis pe ri od, Eu ro pe has co ntinued to invest co n s i d-e rable R & D effo rt into all aspe cts of coal pre p a-rat i o n . This has firmly established Eu ro pe as am a rket leader in coal pre p a ration te c h n o l ogy andhas placed the industry in a strong position to assistcoal prod u cers wo rl dwide to meet futureco m m e rcial and env i ro n m e ntal challenges.

Adva n ced coal pre p a ration sys tems – we l ld eve l o ped in Eu ro pean Union States with gre a tex po rt po te n t i a l .

O n ce coal has been ext ra cte d, it needs to bem oved from the mine to the power station orother place of use.The majori ty of coal is tra n s-po rted over short distances generally by co nveyo ror tru c k ,w h e reas tra i n s, b a rg e s, ships or pipe l i n e sa re used for long distance s. All ty pes of coal tra n s-po rt ation are co n s i d e red safe with the norm a lp reve nt at i ve measures taken at eve ry stage duri n gt ra n s po rt and sto rage to re d u ce po te nt i a le nv i ro n m e ntal impact s.

Coal can be moved safely loca l ly and wo r l d w i d e.

By using water sprays, co m p a cting the coal andenclosing stoc kp i l e s, dust emissions from coal ca nbe co nt ro l l e d. Sealed sys te m s, either pneumatic orcove red co nveyo r s, can be used to move the co a lf rom the stoc kpiles to the combustion or otherp l a nts in which the coal is to be used.The ru n - o f f

of co nt a m i n ated water is limited by appro p ri atedesign of coal sto rage facilities. All water isca refully tre ated be fo re re-use or dispo s a l .

Coal tra n s po rtation and sto rage sys tems arem od e r n , clean and visually acce p t a b l e.

Mo re than 60 % of the coal used for power gener-ation wo rl dwide is consumed within 50 km of itss o u rce. Cu rre nt l y, only about 14 % of the wo rl d’sh a rd coal prod u ction is traded inte rn at i o n a l l y,although this figure is fo re cast to ri s e. In theEu ro pean Union over the past five ye a r s, t h ed e pe n d e n cy on coal impo rts has increased by ove ra third and is fo re cast to increase by a further thirdover the next 10 years to over two thirds of all solidfuels co n s u m e d. ( See En e rgy Ou t l ook to 2020,Special issue 1999).

M o re coal will be moved globally in the future asa co n s e q u e n ce of oil price fluctuation andi n c reasing natural gas price s.

Tra n s po rt ation of hard coal to the po rt of ship-m e nt is generally by ra i l .The feasible distances fo re conomic tra n s po rt ation are limited by co s tco n s i d e rat i o n s.Trains can be up to 1.5 km inlength and ca rry over 10 000 t of co a l . Ot h e rt ra n s po rt options are tru c king by lorry or by inlandwate rway to the po rt .

In the po rt of shipment, the coal is discharged bywagon tippler and moved by belt co nveyor toi nte rm e d i ate stoc kpiles that can take a to t a ltonnage of up to 6 Mt with up to 50 diffe re ntty pes of co a l . Al together wo rl dw i d e, t h e re aresome 180 po rts of shipment with an annualhandling ca p a c i ty of about 670 Mt of co a l .

The marine tra n s po rt ation of coal is by bulkf re i g hte r. Howeve r, most coal tra n s po rt ation isocean-wide or be tween oce a n s. In the re ce i v i n gco u nt ri e s, t h e re are some 185 po rts of discharg ewith handling capacities totalling an annual8 2 0 M t, although this is shared with other bulk dryg ood s. Some of these have dedicated coal te rm i-nals as in the ARA po rts (Am s te rdam Ro t te rd a m

CARNOT xp #10 20/12/01 13:30 Page 14

Antwerp) where, for example, coal discharge isusually by grab crane onto belt conveyors, whichtake the coal to intermediate stockpiles.Thedischarge process at a rate of 15 000–20 000 t/dtakes much longer than loading.

Subsequent inland transportation is from theintermediate stockpiles, where the coal is loadedonto trains and shipped to consumers.The trainsizes deployed are much less, however, and rarely

reach 2 000 t. In some places, for example in theARA ports, the coal can be loaded directly or viaintermediate stores onto inland waterway ships.The standard barge size takes 2 000–2 500 t.

Coal is a worldwide commodity which has a welldeveloped industrial and highly mechanisedoperation, able to supply the coal effectively atcompetitive costs for use anywhere in the world.

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CLEAN COAL TECHNOLOGIES

Colombia

Australia

South Africa

USA, East Coast

China

Canada

USA, West Coast

Russia

145-210 km

115-250 km

625 km

600-900 km

650 km

up to 1100 km

1370-1800 km

up to 4500 km

Figure 11: Distances for transportation of hard coal

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he main uses of coal are in power gener-ation, in industry and in the residentialsector. In the non-power generation

sectors in the OECD region the demandhas been static for a number of years but isgrowing elsewhere. Power generation consump-tion is growing on a worldwide basis.

There are two major considerations which willaffect future coal demand. The first will be theoutcome of competition between coal and gasin power generation. The second will be the

choice of policies by governments to meet thegreenhouse gas commitments proposed atKyoto in 1997.

In most countries, hard coal is mainly mined forinternal markets. This is particularly true of thethree biggest producers, for example China, theUnited States and India. The situation is differentin the cases of Australia, Indonesia, Colombia,Venezuela and Canada, where the majority ofthe coal mined is exported.

Only 15 % of world hard coal production istraded internationally.

At over half a billion tonnes, world trade in coalis around 15 % of total output. The iron and steelindustry has traditionally been the major con-sumer. However, sea-borne trade in steam coals,mainly for power generation, have trebled since1980, while trade in coking coals has remainedconstant.

In this area, the countries with the largestexports were Australia, South Africa and theUnited States. These three countries aloneaccounted for 60 % of world trade by sea.

The list of coal importers is headed by Europe,taking 170 Mt (33 %), followed by Japan with137 Mt (27 %) and Asia with 117 Mt (23 %). Aspecial role is played in Europe by the UnitedStates (as a swing supplier), since its export coal

USES AND MARKETS FOR COAL

T

Figure 12: Uses of coal, percentage of uses

Residential/commercialpublic services

agricultural use of coaltransport

14%

Cement and otherindustrial uses

12%

Metallurgical use of coal

16%

The uses of coal

Power production and/or district heating

58%

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is only marginally competitive on the worldmarket. Market shares are expected to changesignificantly by 2020. Asia will then take the leadwith some 38 %, followed by Europe with 26 %and Japan with 25 % (1999 Data, US DOE 2000).

The main market for coal is the powergeneration sector which will grow significantly.

The chief application for hard coal is powergeneration, with just under 60 % of worldoutput being converted into electricity. The nextmost important hard coal consumers are somekey industries like iron and steel, cement andchemicals.

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CLEAN COAL TECHNOLOGIES

The uses of coal

Other uses

Chemistry

Public services

Conversion

Liquefaction

Gasification

Combustion

Heat

Power

Agricultural use

Transport

Metallurgy

Iron

Steel

Domestic

Industrial

PF

AFBC

PFBC

Chemistry

Power

IGCC

Figure 13: Schematic diagram: uses of coal

Domestic markets85 %

Maritime trade13 %

World hard coal trading 1998

3490 million tonnes

Continental trade 2 %

Figure 14: World hard coal trading

1983

Coking coal Steam coal

1998 1999

111

177 175

96

295 302

Figure 15: World maritime hard coal trade

Source: IEA Coal Information 2000 Source: IEA Coal Information 2000

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Installed New Shut down Installed

4872

4982756

2614

815=31%

1040=38%

143=29%

1712=35%

Coal

Coal

Coal

Coal

1995 2020

Figure 16: Expected growth in installed power generation capacities worldwide (GWe)

Source: DRI-McGraw Hill/ABB 1998

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19

CLEAN COAL TECHNOLOGIES

oday’s environmental debate centres onglobal climate change – yesterday’sdebate related to local and trans-

national emission effect. It is thought thatthe production of CO2 and other greenhousegases (N2O, ozone and methane) from bothnatural and industrial activities affect worldclimate change. The local emissions of acidiccompounds, such as SO2, NOx, and dust, both tothe atmosphere and via water drainage, isknown to affect the health and welfare of plantsand animals over significant land areas.

In-depth development work on all aspects of the‘coal-chain’ has enabled coal to becomesignificantly more environmentally acceptable.The efficiency of modern hard coal-fired powerplants has been increased to over 45 % in recentyears. This has substantially reduced theemissions, not only of sulphur dioxide, nitrogenoxides and dust, but also of carbon dioxide. Atthe same time, in industrialised countries, byretrofitting with flue gas cleaning equipment, thepollutant emissions (SO2, NOX, dust) from coal-fired power plants have also been significantlyreduced, by over 90 % in some cases,

The thermal use of coal (ca r bon) is inev i t a b lyl i n ked to emissions of CO2 and other po l l u t a n t s.1 kg of ca r bon prod u ces 3.7 kg of CO2 ( e q u i va-lent to 0.4 kg of CO2 per kWht h) . The re d u ction inCO2, if modern plants we re to be used wo r l d-wide would be 50 % less than tod ay’s and withthe use of adva n ced clean coal te c h n o l og i e s,S O2, N OX, and dust can be re d u ced to ext re m e lyl ow leve l s.

In the past 100 ye a r s, the te m pe rat u re on thee a rt h’s surf a ce has risen by some 0.6°C.This ri s em ay have been caused by nat u ral climatic fluct u-at i o n s, so that it has not been possible so far top rove the greenhouse gas hy po t h e s i s. The climatem ay also be re s ponding to changes in solara ct i v i ty to a gre ater exte nt than hitherto assumed.Additional unce rt a i nty co m e s, e. g. ,f rom the factt h at sate l l i te measure m e nts in the last 20 ye a r spo i nt to a much lower rise in the te m pe rat u re ofthe at m o s p h e re than has been measured on thee a rt h’s surf a ce.

Although the ev i d e n ce is not yet co n c l u s i ve, t h ecoal industry has backed a po l i cy of pre ca u t i o n a rya ction since the ve ry beginning of the climated e b ate but has confined itself to ‘no re g re tm e a s u re s’, for ex a m p l e, co n s t ru cting new powe rp l a nts inco rpo rating enhanced thermal efficiency.A pioneering role taken by individual co u nt ri e salone offers no solution to this global pro b l e m .

In December 1997, at the World Climate Summitin Kyoto, for the first time firm commitmentswere defined aimed at reducing the emissionsof greenhouse gases. Some 40 industrialisedcountries agreed to a reduction in suchemissions by some 5.2 %, relative to the year1990, by the first commitment period of 2008 to2012. The greenhouses gases are carbon dioxide,methane, nitrous oxide, hydrofluorocarbons,perfluorocarbons and sulphur hexafluoride. Tomeet this goal,most countries will have toreduce their emissions by between 5 and 8 %.The EU and its Member States have agreed tocut their levels by 8 %,with an increase of 27 %for Portugal and decreases of 21 % and 28 % forGermany and Luxembourg respectively.Developing countries have not yet agreed toany specific undertakings to reduce emissions ,but are integrated by way of measures in theclean development mechanism (CDM).

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© Reinhard G.Nießing/RAG

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The negotiations in Kyoto on burden sharing inthe reduction of greenhouse gas emissions,along with the discussion on specific steps andon implementing and ratifying the KyotoProtocol, have shown that international policyon climate protection not only has environ-mental aspects, but also affects key economicpolicy issues for the countries concerned.

Much of the anthropogenic greenhouse gasemissions are associated with satisfying theneeds of mankind for energy and food. The rightto an adequate energy supply claimed bygrowing populations in developing countries and

the resulting growth in the demand for fossilenergy sources clashes with calls for the use offossil fuels to be reduced with a view to achievingprecautionary protection of the climate.The effects of a worldwide rise in coal, oil andgas consumption cannot be offset alone by risesin efficiency and by economy measures inindustrialised countries. In future decades, coalwill continue to make a substantial contributiontowards the rise in the world demand forenergy, since coal can be mined and convertedinto electricity at competitive prices and isavailable in large quantities in both developedand developing countries.

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The key to precautionary climate protectioninvolves making the most efficient use possibleof all energy sources. In the conversion of coalinto electricity and in the further developmentof power plant technology, these efficiency-enhancing potentials have to be exploitedsystematically on a worldwide basis.

Environmental considerations have moved fromspecific plants to local infrastructure, to nationalareas and globally with mitigation on a national/global scale. Much of the development of newsolid fuel/cleaner coal technologies has beendriven by the need for the ‘dirty’ fossil fuel toshow that it can be used cleanly, meet ever morestringent environmental legislation and becompetitive. To date this has been achieved byboth technological advances and also throughlegislative regulations and directives. The latter isshown in Figure 19 for the European Union.

Driven by politics the impact of the use of coalon the environment can be reduced significantlyby the application of advanced technologies.

Some countries have set limits for specificadvanced clean coal technologies in terms ofsulphur dioxide, nitrogen oxides and dustemissions.

In the future, the World Health Organisation andothers worldwide, including the EuropeanUnion, will set action programmes indicating thelevels of emissions needed to be met ondifferent time bases to maximise air quality.Additionally, these organisations, and othersworldwide, will also consider other potentialpollutants and their potential effects on health.In the near to mid-term, global warming is likelyto remain centre stage along with local andregional air quality considerations (concernsabout the impact on health of fine particles andacid deposition on such particles, as well as themigration of substances washed from solidwastes and by-products, will need to beanswered). Additionally, life-cycle analysis ofenvironmental impacts will become the norm.

The reaction to global warming, from a fossil fuelstandpoint, is to utilise natural gas ahead of oiland then coal. This is because it generates 60 %less carbon dioxide for a given output of elec-tricity, compared to coal gasification (IGCC) atabout 30 % when compared to older conven-tional coal-fired power plants. However, gasavailability and recent cost increases relative tosolid fuel and the need commercially forbalanced use of differing fuels are key points forpromoting solid fuel use in the future.

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oal sources are spread over manycountries providing a cheap and secure

indigenous fuel for domestic heating.This is especially true for some important

markets, particularly China.

Although the majority of coal is used as fuel forpower production,the domestic heatingmarket for coal has increased substantially.

In industrialised countries, however, the use ofcoal for domestic heating has been steadilydecreasing over recent decades.

Due to the lower combustion te m pe rat u re s, N Ox

emissions are ty p i cally less with domestic heat-ing than in other combustion sys te m s. Howeve r,S O2 emissions can only be co nt rolled by usingl ow sulphur coal or burning pre - p rocessed fuelswith limestone additives or binders.

Combustion efficiency has been historically lowbut has improved significantly over recentdecades, saving fuel and reducing CO2 and otheremissions.

The development of smokeless fuels allows thereduction of local smoke and smog problems.

In developed countries, the biggest technicaladvance in increasing efficiency has beenachieved by switching from highly inefficientopen fires to closed units. Those units allowbetter combustion control,and the heat can bedirected more effectively into the building.

Closed units continue to be developed toincrease efficiency and decrease emissions.

Larger units can take advantage of moderncontrol systems and the use of co-firingtechniques.

Fully automatic large units are available todayfor district heating, based on,for example,pulverised fuel.

Industrial boilers, in size, are between domesticheating units and large power generationplants. As efficiency decreases with decreasingsize of plant and flue gas SO2 and NOx, control

COMBUSTION TECHNOLOGIES:THE HEAT MARKET

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Power Station Boxberg, Germany. Courtesy of Babcock Borsig Power.

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technology is often not a viable option formedium-sized units, the industrial use of coalcan have a significant negative impact on thelocal environment.

Most industrial boilers are stokers which operatewith naturally staged combustion and haveinherently low NOx emissions which can befurther reduced using flue gas recirculationtechniques. SO2 emissions can be kept belowemission limits using low sulphur coal or mixingcoal with adsorbents or injecting suchadsorbents into the combustion chamber.

Fluidised bed combustion and circulating fluid-ised bed combustion techniques are enteringthe industrial process heat market more andmore.

FBC and CFBC operate on low NOx emissionvalues due to the modest combustion temper-atures and allow low cost retention of sulphurwithin the bed residues.

Cogeneration of heat and p ower, using FBC orCFBC,is becoming more and more popular andis available at plant sizes of less than 10 MWeand up to 80 MWe or more.

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The uses of coal

Other uses Conversion Combustion

Heat

Domestic

Industrial

Figure 20:Schematic diagram: combustion

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enis Papin ope rated the first test machinein 1690, beginning the deve l o p m e nt of

tod ay’s most mod e rn highly efficient ste a mand gas turbines.

The invention of the steam engine enabled manto co nve rt thermal energy into mechanica le n e rgy.

The inve ntion of the three phase elect ri ca lg e n e rator by W. v. Siemens in 1866 subsequent l y

o pened the way to co nve rt, on an industrial sca l e,m e c h a n i cal energy into elect ri cal energy.

E l e ct r i c i ty started to be come the most impo rt a n ts e co n d a ry energy source kn own to man.

Th rough the ce nt u ri e s, e n e rgy consumption pe rcapita has increased by a factor of up to 130. I ntod ay’s deve l o ped wo rl d, m o re than one quarter ofe n e rgy consumption per capita is acco u nted for bye l e ct ri c i ty.

E l e ct r i c i ty is the first sign of improving standard s.

To improve efficiency closed cycles have be e napplied to re ce nt te c h n i cal sys te m s. The idealco m p a rat i ve therm odynamic process is well kn ow nas the Ca rnot cyc l e.

All thermal power generation te c h n o l ogies arebased on the Carnot cyc l e.

As a co n s e q u e n ce of basic therm odynamic laws,the theore t i cally achievable maximum efficiency oft h e rmal power generation is limited by a simplere l ation based only on the lowest and the highest

The uses of coal

Other uses Conversion

Gasification

Combustion

Power

PF

AFBC

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IGCC

Figure 21:Schematic diagram: power generation

POWER GENERATION:CLEAN COAL TECHNOLOGIES

D© Reinald G.Nießing/RAG

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temperature of the cycle.This equation is wellknown as Carnot’s Law. Each technical process, notbeing totally ideal, will have a lower efficiencycompared to the ideal Carnot cycle.

More than 40 % of world thermal powergeneration is based on solid fuels.

Even though the share of solid fuels will decreaseworldwide over the coming years, the use of solidfuels for power generation is expected to increasein absolute terms.

It is expected within the EU-15 that the share ofsolid fuels will increase again after 2010.

The impact on the environment caused by the useof coal in thermal power generation was, and is stillbeing, reduced significantly. Driven by emissionlimits regulations, technology has provided quiteeffective abatement technologies for solid andgaseous pollutants.With highly efficient filters forparticulate matter and the removal and/oravoidance of NOx and SO2 emissions, thermalpower generation today is meeting, withoutproblem, recent emission limits.

The use of all kinds of fossil fuels contributes tothe production of greenhouse gases. Due to theuse of clean coal technologies the contribution ofcoal to any enhanced greenhouse effect is nowless than 20 %.

Liberalisation of the electricity sector emphasisedthe need for cost reduction on the electricalsuppliers of power.

Reducing emissions and maintaining competitiveelectricity costs constitute an enormouschallenge.

The most effective way of achieving theseobjectives is to increase net plant efficiency, whilemaintaining moderate operating and maintenancecosts and a high availability factor. Increasedefficiency will save energy resources and reduceemissions without additional measures.This is alsoespecially true for CO2 emissions.World averageefficiency in thermal power generation is slightly

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Figure 22: Theoretical Carnot efficiency(lower temperature Tl = 313 K (40°C))

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315 MW IGCC, Puertollano, Spain. Courtesy of Elcogas

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above 30 %.The related value for the EuropeanUnion is 39.4 %.This means that compared toworld average, efficiency is higher inside the EU bysome nine percentage points.

Most modern coal-fired power plants todayoperate at an efficiency of about 45 % or evenhigher, emitting only half the amount of CO2

compared to the world average.

Driven by the progress of advanced clean coaltechnologies the efficiency of conventional pul-verised fuel (pf ) fired boilers, which represent themajority of boilers operating worldwide, was im-proved step by step maintaining competitivenessin production costs with low emission levels.

Efficiency primarily depends on the characteristicsof the thermodynamic steam cycle, which hasundergone considerable changes. Steam pressureand temperature have steadily increased, followingimproved characteristics of available materials.Further progress is still achievable taking advan-tage of new materials to accommodate evenhigher steam conditions and thus enable cyclecharacteristics to be further improved.

Efficiencies of 50 % or more are expected to berealistic for hard coal pf fired plants, using steamtemperatures around 700°C.

Even though further development is needed, basicclean coal technologies are commercially availabletoday for a wide range of applications.This includescoal gasification and liquefaction.The latter has nomajor economic impact today but represents anoption/alternative in case of a drastic increase inthe price of oil and gas and might be a limitingfactor against excessive price increases of oil ortransport fuels.

Conventional super-critical pf boilers, based onhard coal, reach an efficiency level of up to 48 %,depending on the location of the plant (e.g. withsea water cooling). A similar development isunder way for lignite-fired plants. A lignite-firedpower plant, based on the BoA technology, willhave a rated efficiency of more than 45 %. Thenext development phase will integrate lignitepre-drying. A plant based on this concept isexpected to reach an efficiency of up to 48 %.

Fluidised bed combustion technology (FBC) usesthe same steam cycle as the conventional pul-verised fuel fired boiler (pf ). It is simply adifferent combustion technology. It is charac-terised on the one hand by a lower temperaturelevel resulting in lower achievable efficienciesand on the other hand by high fuel flexibilityand a low emission level, without the need forsecondary measures such as catalytic or

250 MWe Circulating Fluidized Bed Combustion, Gardanne, France. Courtesy of EDF.

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desulphurisation units. FBC is commerciallyavailable in a stationary or a circulating version.The circulating technique (CFBC) is characterisedby the 250 MWe plant at Gardanne in France.Feasibility studies are under way for a 600 MWeplant.

Increased efficiency can be reached with FBCtechnology using elevated pressure; this tech-nology is referred to as pressurised fluidised bedcombustion (PFBC) which offers the additionaladvantage of a reduction in equipment size.Several plants are now operating around theworld using this technology.

Second generation PFBC has been supported viathe European Commission’s Thermie programme;a plant at Cottbus in Germany is one example ofthe development of this technology.

Some effort has been given to the development ofthe pressurised pulverised coal combustion (PPCC)process.This cycle aims to burn coal in a pressurisedenvironment raising net efficiency to above 50 %.

The integrated gasification combined cycletechnology (IGCC) is based on the gasification ofcoal with oxygen (or air) producing fuel synthesisgas, which consists essentially of hydrogen andcarbon monoxide.This gas is treated and purified,

thus yielding a high-quality fuel gas.The gas issubsequently used in a conventional combinedcycle system consisting of gas and steam turbines.From the former system the exhaust gases are fedto a heat recovery boiler producing steam that isutilised in a steam turbine.

The main advantage of IGCC is the ability to meetthe most stringent environmental requirements.

Overall energy efficiency currently stands at about45 % based on the lower heating value of coal andhas the potential of reaching 51–53 % in theforeseeable future. However, IGCC is a complextechnology, consisting of the combination of achemical plant and a power plant. As a result, theinvestment cost is significantly higher than that fora conventional coal-fired power station.

All major developments for IGCC were supportedby the European Commission in its framework anddemonstration programmes.

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Figure 23: Efficiencies of coal fired powerstations worldwide

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Maturity oftechnology

Range of unitsavailable

Fuel flexibility

Thermalefficiency

OperationalflexibilityEnvironmentalperformance

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Sub-critical pf

Completely provenand commerciallyavailable.All sizes available(300–1000 MWecommon).Burns a wide range ofinternationallytraded coals.

Limited by steamconditions. Moderndesigns achieve 41 %.

Performance limitedat low load.Good SOx and NOx

reduction with FGDand low-NOx systemsfitted. Low efficiency(high CO2 emissions).

Proven to beexcellent.~ 3 years.

Super-critical pf

Substantially provenand commercialplant available.All sizes available.

Burns a wide rangeof internationallytraded coals.

> 45 % now possible.Up to 55 % possiblewith materialsdevelopment.

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Proven to be good.

~ 3 years.

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Substantially proven.Commercial plantavailable.Three sizes available.

Will burn a wide rangeof internationally tradedand low-grade coals.Best suited to low-ashcoals.44 % now possible.Improvements likelywith further R & Dand/or supercriticalsteam cycle.Performance limited atlow load.Good for SOx and NOx

performance andreasonable due torelatively high efficiency.Solid waste may bedifficult to dispose of.Limited experience.

~ 3 years.

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At demonstrationstage on coal.

250–30O MWe,currently limited bygas turbine units.Should use a widerange of internationallytraded coals, thoughnot low-grade, high-ash coals.43 % now possible.>50 % possible withadvanced gas turbinesand further R & D.

Realistically could onlyoperate at base load.Excellent.

Not yet proven.

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Advanced combustion

4x270 MWe PS Huaneng, Peking, China. Courtesy of Babcock Borsig Power.

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o date, the main technique for prod-ucing iron is the melting of iron ore in

blast furnaces. Blast furnaces use coke(made from coal) and small quantities of

limestone to melt the iron ore and to reduce itto iron. Pulverised coal injection is now widelyemployed, substituting some quantities of cokewith cheaper coal.Subsequently, the iron isrefined into steel predominantly in basic oxygenfurnaces.

In 1999, 350 Mt of coal we re used worldwide top rod u ce over 787 million tonnes of crude ste e l .World crude steel prod u ction continues to growbut coal use remains constant due to improve de f f i c i e n cy.

Some 70 % of total steel prod u ction is based onthis prod u ction chain making use of co ke madef rom co a l .

The coke required is produced from bituminouscoal. Specific physical properties are needed tocause coal to soften,liquefy and then re-solidifyinto hard but porous lumps when hea ted in theabsence of air. Low sulphur and phosphorouscontents are required. Being relatively scarce,coking coals are generally more expensive thanthermal coals.

About 1.5 kg of coal is needed to prod u ce 1 kg ofco ke.

M E TA L LU RG I CAL USE OF COA L

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Figure 25:Schematic diagram:other uses of coal,metallurgy

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Coal is carbonised in batteries of coke ovens. Thecoal is heated to above 1 200°C over a period of18–20 hours. The volatile content of the coalevolves as coke oven gas which is subsequentlycleaned to remove impurities and by-productssuch as tar and benzole. It is then used to heatthe ovens themselves and as fuel elsewhere inthe steelworks.

The red-hot coke is pushed out of the ovens,cooled and classified. Only larger sized material– typically above 30 mm – is used in the blastfurnace.

In the process coke supplies the carbon whichacts as a reducing agent to remove the oxygenfrom the iron ore. It provides heat to melt theiron and a load-bearing but permeablestructure, supporting the burden whilst allowingthe reducing gases to pass through.

Production of 1 000 kg of steel needs about630 kg of coal.

Ore, coke and limestone are fed into the top ofthe furnace. The hot air blast and, if PCI isinstalled, the pulverised coal, are injectedthrough nozzles into the base of the furnace.The molten iron or hot metal are periodicallytapped from the bottom of the furnace andtaken directly to the basic oxygen furnace. Steelscrap and more limestone are added. Purity ofiron is 93–95 % at this stage. Oxygen is blownonto the liquid metal. The reaction with theoxygen raises the temperature to over 1 600°Cand oxidises the impurities to leave an almostpure liquid steel.

With pulverised coal injection (PCI), 350–400 kgof coke and 100–200 kg of cheaper coal arerequired – around 700 kg of coal for each tonneof iron produced. Without PCI more coke isused, also equivalent to some 700 kg of coal, butall of it from the more expensive coking coal.Each tonne of steel produced requires approx-imately 90 % hot metal and 10 % scrap andabout 630 kg of coal.

The amount of coal needed to produce 1 kg ofsteel has reduced significantly during the lastdecades and continues to decrease.

About 30 % of world steel is produced in electricarc furnaces. As over 40 % of world powergeneration is based on coal much of theelectricity used in arc furnaces is generated incoal-fired power stations.

The need for blast furnaces, coke ovens andexpensive coking coal is reduced by the devel-opment of new processes, for example, thedirect reduction of iron (DRI). However, coal willstill be used in these plants as a fuel and as areductant. Furthermore DRI will account for onlya small percentage of the world steel output formany years to come.

For the foreseeable future, coal will remainindispensable to the production of steel.

Figure 26: Use of reducing agent (coke)for crude iron production (kg/t crudeiron)

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he bre a k d own of the wo rld pri m a rye n e rgy demand by energy source s

s h ows the share of solid fuels (mainlycoal but also lignite, pe at and biomass)

remaining substantially co n s t a nt until the ye a r2 0 2 0 .The share of oil and gas together re m a i n sco n s t a nt over that time pe ri od but gas takes ove ra significa nt share from oil. I nte rn ational effo rt sshould be made towa rds an eve r - i n c re a s i n gco nt ribution by re n e wable energy sources towo rld energy supply, both in deve l o ped andd eveloping co u nt ri e s. Loo ki n g, for ex a m p l e, atthe coal share this would mean an incre a s ewo rl dwide from over 2000 mtoe in 1990 to ove r3000 mtoe in 2020, e q u i va l e nt to about 38 % ofp ri m a ry energy demand.

Coal is, and will re m a i n , of major impo rt a n ce tothe development of energy re q u i re m e n t swo r l d w i d e.

Coal is available in abundance, is distri b u te dwo rl dwide and has a low and stable pri ce.Th ef u rther application of env i ro n m e nt a l l ya c ceptable sys tems to coal mining, t ra n s po rt anduse activities – in part i c u l a r, to power generat i o nin the future – will need to be sustained.

Coal is abundant, safe and env i ro n m e n t a l lya c ce p t a b l e.

Besides many other impo rt a nt uses, u t i l i s ation ofcoal is most significa nt in elect ri c i ty generat i o n ,s teel and ce m e nt manufact u re, and industri a lp rocess heat i n g. Mo re than half of the total wo rl dcoal prod u ction curre ntly provides some 40 % ofthe wo rl d’s elect ri c i ty. Ma ny co u nt ries are heav i l yd e pe n d e nt on coal for elect ri c i ty prod u ct i o n , fo rexample in Poland 96 % of elect ri c i ty generate d

is from co a l , in South Af ri ca 90 % , in Au s t ralia 78% , in China 70 % and in the Un i ted St ates 53 % .Some EU Me m ber St ates did have majora m o u nts of elect ri c i ty generated from coal butthis is changing ra p i d l y, for example at pre s e nt inDe n m a rk and the Un i ted Ki n g d o m , with theonset over the past decade of cheap nat u ral gas.

The driver for the developing wo r l d ’s futurep ro s pe r i ty is the generation of elect r i c i ty,m a i n ly through the use for co a l . But coal ca nand has to be ‘g re e n’.

Co a l ,h oweve r, cannot remain pre - e m i n e ntwithout the deve l o p m e nt of clean, e f f i c i e nt andco s t - e f fe ct i ve te c h n o l ogies which improve thee f f i c i e n cy and the cleaning of emissions withoutworsening the env i ro n m e nt, h e n ce the need fo rcleaner coal te c h n o l og i e s. In the last two deca d e sa fter the oil pri ce cri s i s, s eve ral adva n ced powe rp l a nt and solid fuel firing co n cepts have be e nstudied with the suppo rt of the EC in re s pe ct oftheir applicat i o n . Special emphasis has be e np l a ced on such te c h n o l ogies that are ex pe cte dto be capable of meeting the stri cter re q u i re-m e nts in te rms of emission co nt rol ande f f i c i e n cy. Special emphasis is also given tod ayto the re d u ction in costs both inve s t m e nt co s t s( E C U / k W) and generation costs (ECU/kWh ) .

CONCLUSIONS AND OUTLOOKFOR SOLID FUELS IN THE EU

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Clean coal technologies provide technicalsolutions for using coal efficiently and in anenvironmentally friendly manner. Coal cancontribute in this way to protect environmentand to enhance the security of energy supply atthe same time.

Clean coal technologies continue to be furtherdeveloped. Electricity generating plant withefficiencies above the worldwide average ofabout 30 %, in other words 50 % and above, willbe achievable in the near future. The use ofcombined heat and power production willprovide further benefit in terms of overallefficiency and primary energy usage.

Work is underway to exploit the opportunities ofcapturing and storing CO2 which is an inevitableby-product of the thermal use of all fossil fuels.Through international cooperation, the EU clean

coal industry will have an excellent opportunityto exploit this work and existing CO2 reductiontechnology on a worldwide basis.

The implementation of the flexibility mech-anisms provided for in the Kyoto Protocol, inparticular the joint implementation and cleandevelopment mechanisms will, in the future, alsoprovide opportunities for the EU clean coalindustry to contribute to the aim of ‘worldwideclean and efficient consumption of coal’.

It is in no one’s interest that climate changecontinues without embracing an affordable ‘noregrets’ policy. Worldwide use of clean coaltechnologies can and will make a substantial‘no regrets’ contribution to the reduction ofgreen house gases for a ‘low-cost’ energyefficient and environmentally acceptable world.

European CommissionFostering the use of clean coal technologies – the CARNOT ProgrammeLuxembourg: Office for Official Publications of the European Communities2001 – 32 pp. – 21 x 29.7 cm

ISBN 92-828-8874-6

AFBC Atmospheric fluidised bed combustion

BoA Braunkohleoptimierungs-Anlage (optimisation equipment for lignite-fired plants)

CCT Clean coal technology

CDM Clean development mechanism

CFBC Circulating fluidised bed combustion

CIS Commonwealth of Independent States (former Soviet Union)

ECSC European Coal and Steel Community

FBC Fluidised bed combustion

FGD Flue gas desulfurisation

IGCC Integrated gasification combined cycle

IGFC Integrated gasification fuel cell system

Mt Million tonnes

Mtoe Million tonnes oil equivalent

MW Megawatt

MWt Megawatt thermal

MWe Megawatt electric

PCI Pulverised coal injection

Pf Pulverised fuel

PFBC Pressurised fluidised bed combustion

PPCC Pressurised pulverised coal combustion

RES Renewable energy sources

ROM Run of mine

R&D Research and development

RTD Research and technological development

SF Solid fuels

Tce Tonne coal equivalent

TWhe Terawatthours electric

WEC World Energy Council

Abbreviations

CARNOT xp #10 15/01/02 9:26 Page 32

carnot cov for pdf 20/12/01 14:33 Page 3

15 12C

S-23-99-314-E

N-C

OFFICE FOR OFFICIAL PUBLICATIONS OF THE EUROPEAN COMMUNITIESL-2985 Luxembourg ,!7IJ2I2-iiihec!

ISBN 92-828-8874-6

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