Study On Dynamic Prediction Method And Techology Of Coal And Gas Outburst At Driving Face

To predict the risk of outburst is the first major problem of gas outburst prevention work. In order to improve the ability of preventing coal and gas outburst, perfect the situation of coal mine safety, increase the forecast accuracy and efficiency of coal and gas outburst area, dynamic prediction of coal and gas outburst was studied.The research methods in this paper are theoretical study, laboratory test, industrial test, etc. The objects of study are the gas emission characteristics of coal and gas outburst disaster accidents in China, the comprehensive tunneling faces and gun digging faces of the typical mines in Huainan mining area. The characteristics of dynamic gas emission and the influence factors and law of dynamic gas emission of the tunneling face were studied. The prediction method of coal and gas outburst, which was judged by the parameters of dynamic gas emission, was put forward. The predicted sensitive indicators and critical values for the working face in different excavating processes and operation processes were ascertained. The dynamic monitoring system and equipment for monitoring gas emission was developed. The specific works are as follows:(1) In this paper, the coal walls of the comprehensive tunneling faces and gun digging faces, the gas emission from fallen coals and its influencing factors were studied. The gas emission characteristics and dynamic laws of the comprehensive tunneling faces and gun digging faces in Huainan mining area were put forward. The mathematical model for the gas emission prediction of the tunneling mining faces was established.(2) Gas emission parameters that are suitable for tunneling faces conditions of Huainan Coal Mine were put forward. The characteristic curves of the gas dynamic emission of the tunneling face, the relationship between the laws of dynamic gas emission and mining geological conditions and the typical characteristics of the dynamic gas emission curves in different work processes were studied. The relationship between the dynamic variation rules and outburst danger was analyzed. The dynamic predictive method for gas emission in tunneling working face was established.(3)Through study, the prediction indexes for blasting driving face are the maximum speed of gas emission after blasting and the accumulated volume of gas emission in the 30min after blasting. The predictive indexes for fully mechanized excavation face are the maximum speed of gas emission and the volume of dynamic gas emission for unit coal in unit time. And the critical values of the index were established.(4)The dynamic monitoring system and equipment, which can monitor the gas emission, were developed. Through monitoring the dynamic gas emission by this system, the outburst danger of the tunneling face could be predicted. It is a new non-contact prediction method, and improves the reliability and continuity for predicting outburst. In addition, it is also a new kind of equipments for improving coal mine safety and reducing disaster accidents, especially for the disaster accidents cased by unexpected events which are more difficult to detect.The dynamic predictive method and the dynamic monitoring technology for gas emission in tunneling working face, which were put forward during the study, can realize the advancing dynamic forecast of the tunneling working face, monitor and report the outburst dangerousness of the working face really-time. Then the accuracy of predicting outstanding dangerousness can reach 100%. It has a guiding significance for reasonably evaluating the gas processing of tunneling working face and developing effective measures to prevent gas emission, provides a reliable technical basis for comprehensively controlling coal mine gas. It also can help the safety production of mine and give play to the advantage of high yield and high efficiency.This system and equipment can help greatly reduce the work amount of predicting outburst and prevention measures, greatly liberate productivity. The study of this paper not only improves the continuous monitoring of dynamic gas emission to a new level, but also further improves the ability of coal mine to prevent and control of gas. It has very significant economic benefits, social benefits and environmental benefits.