Abstract: In view of the problems of narrow space,large dust production and serious secondary dust pollution in comprehensive excavation working face,taking 42221 comprehensive excavation face of 4-2 coal seam in Chaijiagou Well of Yuhua Coal Mine as an example,the dust distribution law along the comprehensive excavation roadway is analyzed through field measurement. Based on the dust reduction theory of ventilation and gravity and the dust reduction technology of aerosol vortex in comprehensive excavation working face is put forward. Combined with gas-water spray dust reduction and centrifugal force dust reduction,an aerosol vortex generator that can be assembled in parallel is designed,and the motion law of dust with different particle sizes in the aerosol vortex generator is described. Based on the modular design idea,an aerosol vortex dust reduction device for comprehensive excavation face is designed,which is composed of six modules:air flow collection,primary filtration, aerosol agglomeration,vortex separation,gravity ash discharge and secondary mist dust suppression. The influence of water supply and air supply pressure on dust reduction efficiency in aerosol vortex dust reduction device is analyzed by experimental test method,and the relationship between dust reduction efficiency and gas-water ratio and liquid-gas ratio is studied. The results show that with the increase of the distance from the head,the dust concentration of 42221 roadways decreases gradually. The total dust reduction efficiency increases with the increase of water supply pressure and air supply pressure. The respirable dust reduction efficiency increases with the increase of water supply pressure,but it first increases and then decreases with the increase of air supply pressure. The treatment air volume increases with the increase of water supply pressure and air supply pressure. The liquid-gas ratio increases with the increase of water supply pressure,but it gradually decreases with the increase of air supply pressure. When the water supply pressure and the air supply pressure are 0. 4 MPa (the gas-water ratio is 1),or when the liquid-gas ratio is controlled at 0. 070~ 0. 075,the comprehensive performance of the aerosol vortex dust reduction device is the best. Field application results show that the average dust concentration reduction rate of the 42221 comprehensive excavation roadway is about 88%.

Key words: dust control,aerosol vortex dust reduction,comprehensive excavation working face,centrifugal force dust reduction,dust reduction device