DETERMINATION OF SPONTANEOUS COMBUSTION “THREE ZONES” IN GOAF OF NO.713 FULLY MECHANIZED LONGWALL OF QINAN COAL MINE

Abstract

Mine fire is one of the major disasters in coal mine. In our country 56% coal mine exists spontaneous combustion problem, among them, the goaf spontaneous combustion take up subject status. The research of spontaneous combustion in the goaf is mainly about heat dissipation zone, oxidation zone and suffocation zone. The distribution condition and the range of the “three zones” spontaneous combustion in goaf is one of important basis of the parameters which are the prevention and control of the spontaneous combustion. For these hold the balance to nitrogen injection of mined-out area, grouting, face mining sequence and mining strength and so on, the scope of the working face spontaneous combustion “three zones” directly decides the position of nitrogen injection, nitrogen injection quantity, nitrogen injection intensity and other technological parameter, and decided the grouting time, grouting quantity, drawing speed of working face and so forth. So, experts and scholars throughout home and overseas have made a lot of research and have acquired some achievements. And the division of coal goaf spontaneous combustion “three zones” is mainly based on the change of oxygen concentration, change of temperature and air leakage speed, etc. How to obtain these parameters? By coal bed itself conditions which include geological conditions, mining technology and ventilation mode is different, and the research approach we adopt is different, the results are quite different. This paper is based on the essence of “three zones”, the factors are comprehensive considered which consist of air leakage speeds, oxygen concentration and temperature to study the coal goaf spontaneous combustion “three zones” distribution laws.