Experimental investigation and application of mine airflow purification and reuse technology

Abstract

To solve the problem of dust concentration higher than the standard on the -415 m roadway in the Fankou lead-zinc mine, a self-made dedusting equipment consisted of chord grid is proposed in this paper. This equipment aims to purify the polluted airflow for deep ventilation in mine. First of all, an image observation is shown that three types of water films on the chord grid surface. Specifically, the chord grid is wetted by the fog drops to form water films and can remove dust from airflow. Then, it is measured that a total dust removal efficiency and resistance are resulted by a single layer of wet chord grids under the conditions of different nozzle out diameters, water spray pressure, and velocities. The results show that: The dust removal efficiency is higher at the experimental conditions meet this conditions(the velocity is 3.5 m/s, the nozzle outlet diameter is 2 mm, and the water supply pressure is 0.75 MPa); (2) The spray pressure seldom influences the resistance of dust removed equipment, whereas this resistance correlates positively with velocities and nozzle out diameters. Finally, one purification system is optimally designed according to the experimental, and applied it in the -415 m middle section of the FKLZM. The field test data showed that the mass concentration of dust meets the quality standard of fresh airflow in metal mine. • A self-made dedusting equipment for mine airflow purification and reuse was proposed. • The dedusting principle of water film making by chord grid was outlined. • The optimal parameters for site application was obtained base on the experiment data. • The developed purification system reduces the dust mass concentration to 0.39 mg/m 3 .