ABSTRACT
Coal has the distinction of being one of the most abundant and cheapest fossil fuel energy sources in the world and is therefore, increasingly used in industries, and for other commercial and domestic purposes (Barooah and Baruah, 1996). Because of these factors coal has been the key energy source for the industrial revolution and is expected to remain so for at least the next two to three decades (Aseefa et al., 2013). Since the time of the industrial
CONTENTS
6.1 Introduction ................................................................................................ 153 6.2 Coal Reserves and Production ................................................................. 155
6.2.1 Global Coal Scenario ..................................................................... 155 6.2.1.1 Coal Production ............................................................... 155
6.2.2 Coal Reserves in India .................................................................. 155 6.2.2.1 Coal Production in India ................................................ 157 6.2.2.2 Categorisation of Coal in India ..................................... 157 6.2.2.3 Grades of Coal in India .................................................. 157
6.3 High Sulphur Coal ..................................................................................... 161 6.3.1 Chemistry of Sulphur in Coal ...................................................... 161
6.3.1.1 Sulphur in Coal: A Worldwide Problem ...................... 162 6.3.1.2 Sulphur Content in Indian Coal .................................... 163 6.3.1.3 Need for Desulphurisation ............................................ 164
6.4 Desulphurisation Processes ..................................................................... 164 6.4.1 Physical Methods of Desulphurisation ....................................... 164 6.4.2 Chemical Methods of Desulphurisation .................................... 165 6.4.3 Bio-Desulphurisation and Microorganisms .............................. 165
6.4.3.1 Bio-Removal of Pyritic Sulphur .................................... 168 6.4.3.2 Bio-Desulphurisation of Organic Sulphur .................. 170 6.4.3.3 Mechanisms of Organic Sulphur Removal ................. 175
6.5 Future Research Directions ...................................................................... 178 References ............................................................................................................. 179
revolution there has been an ever-increasing demand of coal (Acharya et al., 2005). This is because the requirement of energy in terms of heat and electricity generation for the industries has primarily depended on the process of combustion/burning of the coal. Thus, one of the components of enhanced industrial production is attributed to the increased consumption of energy and, for its generation, coal has undoubtedly been a major contributor. Coal-red power plants, steel industries, reneries, smelters, paper and pulp mills and food processing plants are always in need of coal.
