Analysis of a double-pressure double-extraction (DPDE) control dust removal system and optimal installation position of an air curtain generator

To reduce dust pollution during the excavation process of coal mine tunnels, this study combines theoretical analysis, numerical simulation, and on-site measurements to study the distribution of the wind flow field and the diffusion of dust pollution in the double-pressure double-extraction (DPDE) ventilation control and dust removal system. The double longitudinal fan-shaped wind screen generator creates two fan-shaped wind screens that form a wind field directed toward the working surface after hitting the tunnel wall. This setup blocks the dust at the front end of the tunnel. The dust-containing wind flow is jointly pumped by the double extractor cylinders and then absorbed and purified by the double-cylinder convective onboard dust removal fan. The dust concentration behind the wind screen was close to 0 mg/m3 and the dust concentration in the breathing area of the roadheader driver was 218.44 mg/m3. Additionally, we examined the effect of the installation position (L) of the double longitudinal fan-shaped air curtain generator on dust control. The results of the study show that L = 30m is the optimal installation position and the dust concentration at the driver of the roadheader is reduced to less than 5 mg/m3.