scholarly journals Problems in the Classification of Mine Gas Grades and Classification of Coal and Gas Outburst Mine Types

CONVERTER ◽  
2021 ◽  
pp. 426-431
Author(s):  
Xianzhi Shi, Et al.

Since the classification of coal mine gas grade, there has been a classification mode with inconsistent classification basis and progressive relationship between gas mine and coal and gas outburst mine. This paper demonstrates the irrationality of the progressive relationship between coal and gas outburst mines and gas mines from the aspects of different classification materials, inconsistent gas storage media and different disaster control measures, and determines that coal and gas outburst mines and gas mines coexist and are different types of mines. According to the actual amount of outburst coal, the outburst mines are divided into weak, medium, strong and extremely strong outburst mines by using gas content W, coal seam firmness coefficient f and gas pressure P.

2011 ◽  
Vol 121-126 ◽  
pp. 2607-2613
Author(s):  
Qian Ting Hu ◽  
Wen Bin Wu ◽  
Guo Qiang Cheng

Outburst cavity formed during coal and gas outburst can be pear shaped, elliptical, or just like an irregularly elongated ellipsoid, its capacity is always smaller than the volume of ejected coal. And the gas emission quantity is almost 4 to 10 times as gas content in ejected coal. These are two different expressions of the same problem. To find the reasons for the decrease of outburst cavity volume and the increase of gas emission quantity per ton, by using the finite element code ANSYS, the damage zone and the failure zone of the outburst cavity were determined based on the static and dynamic combination method. In this paper, the reason for the decrease of the outburst volume was explained.


2011 ◽  
Vol 255-260 ◽  
pp. 3731-3734
Author(s):  
Sheng Shan Zhao ◽  
Wei Dong Pan ◽  
Xin Wang ◽  
Jia Dun Liu

Based on the complicated geological conditions of coal seam in Xuandong Coal Mine, such as deep burial depth, high gas content, magmatic rock intrusion and so on, the distribution regularities of magmatic rock, gas and geological structures were analyzed and studied. Combining with the practical situation of the dynamic disaster and phenomenon during the mining, the dangerous zones of coal and gas outburst were predicted and regional divided. The research results would have certain significance of practical guide to the outburst prevention and disaster reduction.


2013 ◽  
Vol 734-737 ◽  
pp. 45-51
Author(s):  
Ai He Chen ◽  
Dong Ji Lei ◽  
Yu Gui Zhang

The precise mechanism of the coal and gas outburst is still unresolved, but productive practices in Qidong mine have testified that the coal and gas outburst accidents are predominantly associated with the belt of geological structure, the zone of tectonic coal occurrence and the area of the stress concentration. So it is very important to study characteristics of coal bed gas geology for coal bed gas prediction and prevention. Using gas-geology theory and method, the research focused on the factors of coal and gas outburst, such as coal bed gas occurrence, stress distribution, tectonic coal occurrence and magmatic rock presence within Qidong mine. The result shows that: Qidong mine district could be divided into 4 geological units by 3 faults as the boundary, the faults of Weimiao fault, F2, and F5; there are different conditions and main controlling factors of coal bed gas occurrence within four geological units. The unit I of geology: coal bed gas occurrence conditions are simpler, mainly contacted with the coal burial depth; the unit II: the conditions are more complex, predominantly associated with fault structures; the unit III: as a result of the presence of igneous intrusions, coal bed gas content in unit III is the highest within the whole mine; the unit IV: major factor of the conditions is the fold caused by strata uplift, which also leads to a large number of gas emissions. 25 coal and gas outburst accidents all occurred within the unit II of geology.


2012 ◽  
Vol 524-527 ◽  
pp. 752-757 ◽  
Author(s):  
Li Wei Chen ◽  
Jin Chao Chen

In order to improve the heading speed of the seam gateway and mitigate the problem of mining maladjustment in high-gas mines and coal and gas outburst mines which are almost low permeability, highly-gas content and it is difficult to eliminate the gas-outburst dangerous by the conventional pre-drainage technologies in a short period. The paper puts forward the view of strip gas pre-drainage with boreholes along coal seam from front traverse of the rock roadway over the seam roof, which can greatly save the time of gas pre-drainage to eliminate gas outburst dangerous by drilling and gas pre-drainage simultaneously for the trips between two traverses. The test results showed that the ratio of roadway driving to gas pre-drainage were increased from 0.31 to 3.6,the speed of driving increased from 50m to 105m per month and the time of roadway drilling and blasting heading per hundred meters from78 days reduced to 19 days. So this technology can greatly mitigate the replacement contradiction of mining and roadway driving.


2012 ◽  
Vol 524-527 ◽  
pp. 325-329 ◽  
Author(s):  
Shou Tao Hu ◽  
Bai Sheng Nie ◽  
Ming Ju Liu ◽  
Yan Wei Liu ◽  
Xiang Chun Li ◽  
...  

According to the questions of long eliminating coal and gas outburst period, large projects and slow driving came from the regional measurement of drilling hole ,the paper select 2371 (1) rail transport roadway as experiment for using along seam long drilling as a regional measurement to eliminate coal and gas outburst. Since the regional measurement of along seam long drilling had been carried out, the remaining gas content decreased more than 60%, max Smax was 5.4kg/m, max qmax was 2.01/min.Both Smax and qmax were not beyond the standard. Gas concentrations were not overrun. Gas emission decreased in the roadway afterward. The regional measurement eliminated the risk of coal and gas outburst in effect. Heading face promoted 423m forward safely. The max January footage could reach 120m.Achieve driving of heading face safely and fast.


2012 ◽  
Vol 524-527 ◽  
pp. 535-538
Author(s):  
Ming Deng ◽  
De Fang Liu ◽  
Qin Hua Chen

By defining and studying the time series of gas emission concentration (which was called G series in the paper), weighted moving average (WMA) model for pre-warning of coal and gas outburst was developed. The long & short-term trend curved lines of G series were drawn with the data of “3.30” coal and gas outburst of a coal mine. The results indicate, at normal production periods, coal body containing gas kept relatively steady, the gas content curved line, and long & short-term trend curved lines all changed mildly. Before occurring of outburst, some abnormal variations were found, including roadway body broken, gas energy released obvious increase or fluctuation of gas emission concentration, the gas content curved line passing through moving average curved line, long-term and short-term trend curved lines breaking through each other. The result of this study can be selected as the precursors to pre-warning coal and gas outburst.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
W. Nie ◽  
Y. Liu ◽  
C. J. Li ◽  
J. Xu

Coal and gas outburst is a phenomenon characterized by the ejection of gas and coal from the solid face of a mine. Physical minioutburst experiments are a very important tool for analyzing outbursts of coal and gas. However, few reports have focused on the safety problem produced by gas concentration or the role of gas spread during the physical experiments. In this study, we designed a simple monitoring and control system for the safety of staff during the minioutburst experiments. The results showed that, in the simulation of four dangerous situations, the system based on a sensors feedback loop can monitor the development of gas content in the temporal and spatial domains for the enhancement of accurate warnings. The system also automatically chooses the appropriate ventilation measures to lower the gas content considering different degrees of danger.


Sign in / Sign up

Export Citation Format

Share Document