Development And Experimental Application Of Downhole Ventilation Purification Device

The harmful substances in the exhaust emissions of diesel equipment is the occupational hazard factor which can not be ignored in the closed space in underground mine. However, the exhaust discharged pollute environment in underground mine when trackless equipment works efficiently. The diffuse soot and other pollutants in the work surface and haulage tunnel reduce the visibility for work, but also it brings great harm to health of underground staff.13-8# mining area of the old factory of Yunnan Tin Group is located in high altitude area where the air is relatively thin and the supply of fresh air is very difficult. It makes that the effect of all kinds of the diesel engine exhaust gas purification device used at present is discounted and the problem of the occupational hazard management to exhaust emission becomes more pronouncedIn general, three measures of strengthening mine ventilation and using airborne purification and environmental purification device are used to manage comprehensively the diesel exhaust. Among them, there is no mature achievements yet for exhaust gas purification device for underground environment in addition to set up outside the curtain. In the paper, the Venturi scrubber exhaust gas purification device is studied to meet the problems of technological innovation of exhaust air purification of the environment in the underground.In this paper, under the guidance of the theory of dust removal principle of Venturi scrubber, the possibility of Venturi scrubber can be used to remove dust particles whose size less than 0.1 μm and gaseous pollutants is considered. In the design, the paper improves the advantages of simple structure, small occupation area convenient operation and maintenance of Venturi scrubber exhaust gas purification device. Follow the rules of technical development, the paper do the work of the development and experimental application of a new type of safety facilities from the theoretical analysis to the selection, to make the design of experimental device for industrial test and simulation test in laboratory and improvement for test and finally to the field test in the underground.In order to remedy the deficiency of field experimental conditions can not be adjusted by parameters of the test group, the paper reproduced the effect of purifying soot of Venturi scrubber exhaust gas purification device through the establishment of CFD numerical simulation model and the measured data in the field test in 13-8# mining area of the old factory of Yunnan Tin Group. On the basis of verifying the validity of the simulation model, the paper proves the feasibility of the design of the purification device to solve the soot pollution problems in underground haulage tunnel.According to the analysis of field test and numerical simulation, the conclusions are as follows:1)During the process of the simulation test in the laboratory, in the test conditions of "large volume, high water pressure", the efficiency of purifying soot of the model of Venturi scrubber exhaust gas purification device is the highest, reaching 70%.2)During the process of the field test, the efficiency of purifying soot of Venturi scrubber exhaust gas purification device can reach 46.9% in ground test stage; while the efficiency of purifying soot of Venturi scrubber exhaust gas purification device can reach 36.5% in the test under harsh conditions.3)The CFD calculation shows that the purifying area in front of the device where soot concentration is decreased reach 96% when the entrance wind speed of Venturi scrubber exhaust gas purification device reach 20m/s. When the wind speed decreases, the area of soot concentration decreased is reduced gradually.