Research On The Comprehensive Gas Control Of High Gas-containing And Easy Self-ignition Isolated Island Fully Mechanized Cola Face

The coal mine gas can cause outburst, explosion, combustion and other security incidents, and has always been the threats and conflicts which affect coal mine safety production. Due to coexist of gas and coal spontaneous combustion disasters on high gas-containing and easy self-ignition workface, the coal mine safety production faces double threats. To solve the problem of face gas, improve air flow, gas extraction and other measures are being commonly used, these two measures can effectively solve the problem of face gas, but is also easy to cause air leakage of gob, furthermore, lead to spontaneous combustion of residual coal in goaf. Therfore, we should not ignore the requirements of fire prevention and should consider and manage simultaneously on the process of gas control.This paper take Huainan dingji colliery1412(1) workface as background,and did field monitoring of this high gas-containing and easy self-ignition.Isolated island fully mechanized coal workface of analysis and research had been done on techniques for the comprehensive gas control of high gas-containing and easy self-ignition isolated island fully mechanized coal workface, through theoretical analysis, experimental analysis, numerical simulation and on-site monitoring.(1) Through theoretical analysis, a better understanding of goaf gas transport and distribution law has been gained, thus, could put forward its applicaton on comprehensive gas control very well. Divide1412(1) goaf into "three zones" by gob overburden "three zones" theory, and carry out CFD numerical simulation of goaf gas transport and distribution rules on the basis of field measured parameters.(2) Take gas control as the exerting point of CFD numerical simulation and select the air flow and gas extraction as the two main gas control measures to analyze changes of the distribution of goaf concentration field and spontaneous combustion "three zones". Then the simulation results on goaf gas transport and distribution law was been used in field practice. It can not only guide the practical work, but also test the accuracy of the numerical simulation, amend simulation ideas and process, which can better guide the future practice.(3) By analysis of the prediction amount of gas emission results, the gas control measures were developed and implemented, and analyzed effect of Ventilation Air Methane (VAM) and gas extraction through on-site monitoring. The average of the wind gas amount is9.25m3/min, and the average of gas extraction efficiency is80%.In addition, in order to prevent the coal spontaneous combustion while on the process of gas control, the fire prevention schemes were proposed and the conditions of coal spontaneous combustion were monitoried, mealwhile, analyzed the monitoring results, according to the theory of coal spontaneous combustion and experiment on spontaneous combustion characteristics of coal samples. It is proposed that the goaf only occurs partial oxidation, the oxidation was on a low level, furthermore the problem of spontaneous combustion of coal has been effectively astricted.