EVALUATION OF SUITABLE TECHNOLOGY FOR PREVENTION AND CONTROL OF SPONTANEOUS HEATING/FIRE IN COAL MINES

The problem of spontaneous heating/fire in coal mines is very serious and needs immediate attention. A mine fire is not only dangerous to the workers employed in the mine, but it also results in heavy loss of valuable coal, a national asset being the primary source of energy. Most of the fires in different coalfields originated from many decades ago in collapsed workings of thick seams, at shallow depth. Where the workings were at shallow depths and the extracted seam thickness were high subsidence cracks appeared on the surface providing a path of the air flow to the fire zone. In this way many, underground fires turned to Surface fires at a later stage. If exposed coal benches of the opencast mines are left idle for longer times i.e. beyond its incubation period, then doe to the intrinsic properties of coal. oxidation takes place and it catches fire. Besides this. there are several incidences of fire originating from quarry edges due to dumping of hot ash and illicit distillation in abandoned workings near quarry edges. There are different technologies available in the different parts of the world for prevention and control of fire such as surface sealing. trench cutting, flooding, filling of incombustible material, inertisation (Nitrogen and carbondioxide). fire protective coating, grouting and application of chemical inhibitors. All technologies cannot apply everywhere. The application of technology for prevention & control of fire will vary case-to-case and site-to-site basis. After application of these technologies, we are getting good results for prevention and control of fire. But time has come to evaluate the suitable technology for prevention and control of fire in underground and surface coal mines. Firstly the Situation of fire should be studied in detail and secondly the suitable technology should be selected as per site-specific condition and applied. The technology should be economical and suitable for the existing Situation of fire. The objective of the paper is to describe the different situation of fire and evaluation of suitable technology for prevention and control of spontaneous heating/fire in coal mines.