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Goldsource Mines Inc.

2019

Coal Basics

 

Origins of Coal

Coal is a readily combustible black or brownish-black sedimentary rock primarily composed of carbon and hydrogen and sometimes small quantities of sulfur.  It is a fossil fuel formed by plant remains buried under layers of mud or water.  The layers prevented biodegrading, thereby preserving the carbon that the plants had derived from the atmosphere through photosynthesis. It is carbon that gives coal most of its energy-producing capability.

The most abundant deposits of coal come from what were once forests in warm, swampy areas, between 300 and 400 million years ago. Plant matter eventually changed into a substance called peat.  Over millions of years, increasing pressure and heat gradually transformed the peat into coal.  Scientists estimate that from 3 to 7 feet of compacted plant matter is required to form 1 foot of bituminous coal. 

Types of coal

As geological processes apply pressure to dead biotic matter, over time and under suitable conditions, it is transformed successively into peat, lignite, sub-bituminous coal, bituminous coal, anthracite, and finally graphite.

  • Peat, considered to be a precursor of coal, has industrial importance as a fuel in some countries, such as Ireland and Finland.
  • Lignite, also referred to as brown coal, is the lowest rank of coal and used almost exclusively as fuel for electric power generation. Jet is a compact form of lignite that is sometimes polished and has been used as an ornamental stone since ancient times.
  • Sub-bituminous coal, whose properties range from those of lignite to those of bituminous coal, is used primarily as fuel for steam-electric power generation. Additionally, it is an important source of hydrocarbons for the chemical synthesis industry.
  • Bituminous coal, a dense mineral, is usually black but sometimes dark brown, often with well-defined bands of bright and dull material.  It is used primarily as fuel in steam-electric power generation, with substantial quantities also used for heat and power applications in manufacturing and to make coke for steel making.
  • Anthracite is a harder, glossy, black coal used primarily for residential and commercial space heating.
  • Graphite is technically the highest rank of coal, but it is difficult to ignite and so is not commonly used as a fuel.  It is mostly used in pencils and, when powdered, as a lubricant. 

Early Use

Evidence of coal use by early civilizations occurred between 200BC and 200AD.  During this time period China, the Roman Empire and parts of Western Europe used and traded coal. However, there is no evidence that the product was of great importance before 1000 AD.  Underground coal mining did not begin until the 13th century. The development of the Industrial Revolution led to the large-scale use of coal to fuel steam engines. 

Coal as Fuel in Modern Times

Food and electricity are the two largest commodities purchased by consumers in North America each year.  Demand for electricity has continued to increase since the 1970’s.  Although society has become more efficient in its energy use, demand for electricity has grown due to the introduction of new technologies, such as the internet and the electrical requirements to power millions of computers.  Coal-fueled power plants generate approximately 2.0 kW·h of electricity per kilogram of burned coal.  It takes just under 0.5 tons of coal to power a computer for a full year.

Coal has been the fastest-growing fuel source for each of the past five years.  It generates more electricity worldwide than any other source, and it is responsible for about 40% of the world’s electricity.  World coal consumption is about 6.2 billion tons annually.  Coal generates about 50% of the electricity used in North America.

Primarily used as a solid fuel to produce electricity and heat through combustion, the most common method of converting coal is to pulverize it and then burn it in a furnace with a boiler. The furnace heat converts the boiler water to steam, which is then used to spin turbines which turn generators and create electricity. The thermodynamic efficiency of this process has been improved over time.  

Refined Coal

Refined coal is the product of a coal upgrading technology that removes moisture, ash and certain pollutants from lower-rank coals such as sub-bituminous and lignite coals.  It is one form of several pre-combustion processes that alter coal's characteristics before it is burned.

Additional Uses for Coal 

Coking

Coke is derived from low-ash, low-sulfur bituminous coal, baked in an oven without oxygen at high temperatures.  Coke is used as a reducing agent in smelting iron ore in a blast furnace.

Gasification

High prices of oil and natural gas are leading to increased interest in "BTU Conversion" technologies such as gasification.  In this process, coal is mixed with oxygen and steam while also being heated and pressurized. During the reaction, oxygen and water molecules oxidize the coal into carbon monoxide (CO) while also releasing hydrogen (H2) gas.  Refiners collect synthesis gas at this stage.

Liquefaction: Coal-To-Liquids

Coal can also be converted into liquid fuels such as gasoline or diesel by several different processes. In the direct liquefaction processes, the coal is either hydrogenated or carbonized.  In hydrogenation, coal is liquefied by mixing it with hydrogen gas and heating the combination.  Carbonization (LTC), which is a low temperature process, can also convert coal into a liquid fuel.

The future of Coal

Clean Coal Technology

Although there is not a current economic solution to creating clean coal, many are searching for ways to achieve clean coal at a reasonable cost.

The goal is to remove carbon dioxide from the coal conversion process.  The options listed represent the most logical path to the lowest cost of carbon reduction.  The first option is to increase the efficiency of the carbon that is processed.  The next option is to partially replace fossil fuels with biomass, which will reduce CO2.  The last option is to capture the remaining CO2 for containment.  The final option is not yet economically feasible and is the farthest from being cost effective.  However, it is the process that has gained the most media attention. 

New coal fired power plants are being designed for higher efficiency in minimizing CO2 and other emissions.  Lower cost technologies for CO2 capture are currently in the development stage. 

World coal reserves

Coal is extracted from the ground by either underground mining or open pit mining.  The total known deposits recoverable by current technologies is sufficient for 300 years' use at current consumption levels.

Proved recoverable coal reserves at the start of 2007 (million tonnes (teragrams))

Country   

 Bituminous & anthracite  

SubBituminous & lignite  

         TOTAL 

             Share 

USA

111,338

135,305

246,643

27.1

Russia

49,088

107,922

157,010

17.3

China

62,200

52,300

114,500

12.6

India

90,085

2,360

92,445

10.2

Australia

38,600

39,900

78,500

8.6

South Africa

48,750

0

48,750

5.4

Ukraine

16,274

17,879

34,153

3.8

Kazakhstan

28,151

3,128

31,279

3.4

Poland

14,000

0

14,000

1.5

Brazil

0

10,113

10,113

1.1

Germany

183

6,556

6,739

0.7

Colombia

6,230

381

6,611

0.7

Canada

3,471

3,107

6,578

0.7

Czech Republic

2,094

3,458

5,552

0.6

Indonesia

740

4,228

4,968

0.5

Turkey

278

3,908

4,186

0.5

Greece

0

3,900

3,900

0.4

Hungary

198

3,159

3,357

0.4

Pakistan

0

3,300

3,300

0.3

Bulgaria

4

2,183

2,187

0.2

Thailand

0

1,354

1,354

0.1

North Korea

300

300

600

0.1

New Zealand

33

538

571

0.1

Spain

200

330

530

0.1

Zimbabwe

502

0

502

0.1

Romania

22

472

494

0.1

Venezuela

479

0

479

0.1

TOTAL

478,771

430,293

909,064

100.0

World Coal Consumption by Region, Reference Case, 1990-2020
                 (Million Short Tons)

The future markets for coal consumption are listed below.  China is expected to increase by more than any other country doubling the US as well as its current consumption by 2025.  Other countries with notable growth include India and Mexico.

Region/Country  

History  

Projections  

Average Annual Percent Change, 1999-2020  

1990  

1998  

1999  

2005  

2010  

2015  

2020  

Industrialized Countries

               

  North America

959

1,121

1,122

1,263

1,349

1,401

1,480

1.3

    United States 

895

1,040

1,045

1,176

1,251

1,294

1,365

1.3

    Canada

55

66

63

66

73

78

83

1.3

    Mexico

9

15

13

21

25

29

32

4.3

  Western Europe

894

566

546

498

485

469

436

-1.1

    United Kingdom

119

70

65

60

58

53

43

-1.9

    France

35

29

26

23

16

17

14

-3.1

    Germany

528

269

258

237

237

233

219

-0.8

    Italy

23

19

19

17

17

15

15

-1.2

    Netherlands

15

16

14

12

8

8

7

-3.3

    Other Western Europe

173

164

165

149

148

143

138

-0.8

  Industrialized Asia

231

287

295

311

323

332

337

0.6

    Japan

125

144

149

164

173

181

185

1.0

    Australasia

106

142

145

148

149

151

152

0.2

      Total Industrialized

2,084

1,974

1,963

2,072

2,157

2,201

2,252

0.7

                 

EE/FSU

               

  Former Soviet Union

848

396

414

421

397

364

326

-1.1

  Eastern Europe

527

414

363

361

330

298

263

-1.5

    Total EE/FSU

1,375

810

778

782

727

662

589

-1.3

                 

Developing Countries

               

Region/Country  

History  

Projections  

Average Annual Percent Change, 1999-2020  

1990  

1998  

1999  

2005  

2010  

2015  

2020  

                 

  Developing Asia

1,583

1,903

1,686

2,141

2,577

3,004

3,515

3.6

    China

1,124

1,300

1,075

1,421

1,797

2,170

2,592

4.3

    India

242

333

348

414

450

482

546

2.2

    South Korea

42

60

65

81

89

94

96

1.8

    Other Asia

175

210

197

226

241

258

282

1.7

  Middle East

66

99

96

101

119

125

127

1.3

    Turkey

60

86

84

88

98

102

104

1.0

    Other Middle East

6

12

12

12

21

23

23

3.1

  Africa

152

181

177

186

191

203

212

0.9

  Central and South America

26

42

41

43

47

52

58

1.7

    Brazil

17

28

27

30

35

40

47

2.6

    Other Central/South America

9

15

14

14

12

12

11

-0.9

      Total Developing

1,827

2,226

2,000

2,472

2,935

3,384

3,912

3.2

                 

Total World

5,287

5,009

4,740

5,326

5,819

6,247

6,753

1.7

                 

Annex I

               

  Industrialized

2,075

1,959

1,950

2,051

2,132

2,172

2,220

0.6

  EE/FSU

1,166

702

686

692

650

594

535

-1.2

    Total Annex I

3,242

2,660

2,635

2,743

2,781

2,766

2,755

0.2

Sources: History: Energy Information Administration (EIA), International Energy Annual 1999, DOE/EIA-0219(99) (Washington, DC, February 2001). Projections: EIA, Annual Energy Outlook 2002, DOE/EIA-0383(2002) (Washington, DC, December 2001), Table A16; and World Energy Projection System (2002).

Disclaimer:  The information in this section is believed to be from reliable sources but the company takes no responsibility for its content or accuracy.