Fire Fighting in XIII/XIV Seam Sijua Colliery - A Case Study

Xlll and XIV seams in Sijua colliery of Tata Steel are 8.4 m and 5.59 m thick at approx, depth of 240m. Seams are appearing contiguously with a parting of 1.5 m. Indication of spontaneous heating was observed in the goaved out area in the year 1982, which was effectively sealed off and adjacent areas were worked. Due to lack of suitable method to work thick seams, conventional bord and pillar method was practiced and the percentage of extraction was poor and it is approximately 20%. Sealing off the goaves was also largely ineffective due to formation of cracks in coal pillars, roof and floor and isolation stopping itself. This resulted in active fire in XIII/XIV seams causing loss of approximately 36 Iakh tonnes of prime coking coal valued at Rs. 500 crore. Tata Steel took up the challenge of controlling the fire since 1994 in a systematic way. Various methods narrated below, viz. cement plastering of stoppings and adjoining walls, fillings up of cracks by cement or chemical gel injection, dynamic pressure balancing, injection of inert gas etc. were done in a systematic manner. Regular monitoring of atmosphere behind the sealed off area indicates that the situation is under control.