A New Design of Double-Stage Parallel Adding Equipment Used for Dust Suppression in Underground Coal Mines

Abstract

In order to solve the problems of conventional single-stage adding equipment, such as high adding proportion, easy to generate cavitation, large pressure loss and low pressure ratio, an original design of double-stage parallel adding equipment is proposed. Its performance is investigated experimentally under different working flow and outlet pressure and compared with the single-stage jet equipment. Testing results show that the adding proportion of double-stage parallel adding equipment is less than that of the single-stage one, and the cavitation flow is higher. The new equipment can decrease pressure loss, inlet pressure and improve pressure ratio, which lowers the energy loss of adding equipment and raises its driving ability in application. An adding proportion of 4.6 ‰ and an outlet pressure of 0.16–0.18 MPa were realized when the double-stage parallel adding equipment was used to add foaming agent for dust suppression with foam (DSF). The marked reduction in the adding proportion of foaming agent significantly reduces foam production cost. Therefore, it is believed that the study would lay an important foundation for the widespread application of DSF in underground coal mines.