Pointed out the key research areas for the future development of coal fire disaster prevention and control technology
This is the research result of the team of Professor Deng Jun from Xi'an University of Science and Technology. The researchers put forward key research areas in the future development of coal fire disaster prevention and control technology and key issues in coal fire research.
The effect of low temperature oxidation on the amount of CO produced during coal pulverization is revealed.
This is the latest achievement of the team of researchers Liang Yuntao of the State Key Laboratory of Coal Mine Safety Technology. The researchers found that there is no quantitative relationship between the specific surface area of ​​coal and the amount of CO produced in an anaerobic environment. In an aerobic environment, CO is prone to low temperature oxidation during coal pulverization, and the ratio of coal specific surface area to CO production is fitted. As a quadratic parabola, as the specific surface area of ​​coal increases within a certain range, the amount of CO generated gradually increases and eventually stabilizes.
Established an early indicator system for coal spontaneous combustion
This is the result of a joint study between Professor Chen Xiaokun and Yu Zhijin of Xi'an University of Science and Technology. They determined CO and C2H4 as the main early forecast indicators, proposed a theoretical model of CO concentration in the upper corner, and calculated the limit index with a volume fraction of 0.04% to predict the oxidation degree of the coal in the goaf.
Self-ignition model of coal pile was established by numerical simulation software
This is the latest achievement of the research team of Professor Qi Qingjie from Liaoning University of Engineering and Technology. The coal pile porosity studied was 0.2-0.6. The researchers found that in the range of spontaneous combustion wind speed, with the increase of wind speed, the most spontaneous combustion position of coal piles with different porosity shows the movement law of “left middle part - middle middle upper part - right upper partâ€, and the initial spontaneous combustion point has commonality. Both appear at the same coordinate position. The result can provide a reference for the precise determination of the spontaneous combustion of coal piles.
Revealing the law of "three belts" of spontaneous combustion in goaf in thick coal seam layered mining
This is the result of the team of Professor Zhang Xinhai from Xi'an University of Science and Technology. In order to solve the problem of high self-ignition risk of the coal mining in the goaf of the spontaneous combustion of thick coal seams in the 5101 working face of a mine in northern Shaanxi, the researchers adopted the nitrogen injection during the mining period, and the fire prevention and grouting on both sides of the goaf. Technical measures and performance tests were carried out to ensure normal recovery of the working face.
Simulated the influence time and migration law of CO in the fire area on the working face
This is the latest achievement of the research team of Professor Wang Haiyan from China University of Mining and Technology (Beijing). By constructing the physical model and boundary conditions of the fire zone, the researchers simulated the impact time of the fire zone CO to the 1604 working face under the three conditions of the working face not reaching the fire zone, the working face being below the fire zone, and the working face crossing the fire zone. Movement law. The simulation results are similar to the actual monitoring rules of the fire area, which can provide a basis for the development of mining area recovery planning and safety measures.
Revealing the law of high temperature point migration in the spontaneous combustion process of coal bunker
This is the latest achievement of the team of Professor Jin Yongfei of Xi'an University of Science and Technology. The study found that the high temperature point first appeared at the height of the coal bunker 3/5, and then gradually moved in the center axial direction of the lower part of the coal bunker, while moving along the vertical central axis toward the southeast, and finally stayed closer to the wind side. The lower part of the coal bunker develops toward a position where the void ratio at the edge of the bunker is larger.
Finding a method for spontaneously controlling coal body in goaf in high-temperature fully mechanized caving face
This is the result of the joint production of Professor Ma Wei from Xi'an University of Science and Technology and Shandong New Dragon Energy Co., Ltd. The researchers found that high geothermal coal surface to increase the number of reactive functional groups and the number of active intermediate products, significantly enhanced exothermic oxidation; oxidation temperature increasing with increase range. A fire prevention method is proposed, which combines plugging and nitrogen injection to reduce the oxidation of coal, resisting foaming and resisting coal, injecting liquid carbon dioxide and injecting glue to inhibit the increase of coal temperature.
Reveals variation radical spontaneous combustion of coal
This is the result of the research team of Associate Professor Zhu Lingqi from North China University of Technology. The study found that the presence of free radicals and the number of different coals CO yield big gap, lignite CO highest yield, the lowest concentration of free radicals, lean coal and vice versa. DESCRIPTION lower coal rank fewer the number of free radicals, the greater the CO oxidation process yield, the lower the critical temperature, the easier the combustion.
Proposed fire prevention technology for implementing pressure equalization in stages during the withdrawal of the working face
This is a research associate professor at China University of Mining Applying Three team results. I.e. the expansion stage return channel, using the local fan damper joint equalization to improve the face pressure energy, suppressing external leakage; the equipment removing stage, and use of combination regulating face return airway damper effective ventilation area Therefore, the ventilation area of ​​the damper is smaller than the effective ventilation area of ​​the working surface, thereby reducing internal air leakage.
Determine the best working point of the working face pressure equalization ventilation system
This is the research result of Wang Zhifeng, deputy chief engineer of Shangwan Coal Mine Technology of Shenhua Shendong Coal Group Co., Ltd. Using this technology monkey, the oxygen volume fraction of the return air angle of 22102 working face in Shangwan Coal Mine has been maintained at 18.0%~18.5%, and the carbon monoxide volume fraction has been maintained at 5×10-6~20×10-6, ensuring the working face. Safe recovery.
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