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UNDERGROUND COAL GASSIFICATION

ARUN KUMAR LAHRE

FACULTY OF TECHNOLOGY(MINING)

KALINGA UNIVERSITY,RAIPUR

Coal gasification beneath the ground surface is the technological process of converting coal to fuel gas majorly rich in hydrogen and carbon monoxide. This method was adopted after the oil crisis in the late 1970s which gave rise to different advanced coal utilization techniques. Gasification generally is the process that converts any carbonaceous raw material like coal into synthetic gas,gasification occurs in a gasifier(high temperature/pressure vessel where air and steam is directly reacted with feed materials like coal),causing different forms of chemical reaction to occur that converts feed to syngas, syngas has variety of uses,it can be further converted to hydrogen and carbon dioxide by addition of hot steams and catalyst reactor.

As compared to the current scenario of coal mining in india, we first extract the coal from the seam by different mining methods which requires huge mechanization and manpower with all safety standards,then the coal is send to washries for concentration then it may be used to produce electricity or any other form of energy. But in the U/G gasification technique the borehole drivages(generally two,one for feeding air or catalyst other one for production) are driven directly from the surface to the coal seam , once the drivage touches the seam mouth, feeding of air and some catalyst are done which propagates chemical reaction in three forms,OXIDATION,REDUCTION&DISTILLATION.Once the oxidation process is completed it releases some amount of heat which directly converts to fire in the coal seam and coal being carbon full content the fire propogates from one end to other releasing gaseous matter which is further converted into useful products.

In india the first coal gasification project has been setup by Jindal Steel&Power at angul orrisa and it plans to setup more such plants seeing the success of one and if adequate supply of raw materials are ensured. India has huge reserve of low rank coal which have some kind of debris in it that is why gasification process are adopting so that in less investment technique we could gain fuel gas. If more such projects comes in the technicality ,gasification can help our country overcome the demand of fuel.