Using CFD to Simulate the Concentration of Polluting and Harmful Gases in the Roadway of Non-Metallic Mines Reveals Its Migration Law

Abstract

The green and pollution-free mining of resources has always been a research field that people have focused on. In the process of mining resources, the production of CO, SO2 and other pollutants directly affects the health of miners and the atmospheric environment in the mining area. Therefore, it is particularly important to deal with and control the polluting gases generated by mining. Taking the underground roadway of a coal mine in Hengdong City, Hunan Province, as the research object, we studied the migration law of pollutant gas there. Comsol software was used to determine the changing state of pollutant gas migration in the roadway, and a simulation model of the wind field and the pollutant concentration field in the roadway under turbulent conditions was established. The results showed that, when the air flow moved to the front face of the roadway, it generated backflow to form a counterclockwise-rotating air flow vortex. Here, the air flow stagnated, hindering the diffusion of pollutants. The gas moved with the air flow in the roadway, and the flow’s velocity decreased in the middle of the roadway, causing pollutants to accumulate. The whole wind field tended to be stable at a plane 25 m from the roadway’s outlet. This indicates that the middle part of the roadway is the place where the polluted gas accumulates, and it is of representative significance to study the concentration of the polluted gas in the roadway in this section.

Minimum Cost Pathfinding Algorithm for the Determination of Optimal Paths under Airflow Constraints

“…In 2018, Ren and Wang used CFD modeling to construct realizations of dust and gas flow dispersion across longwall faces in underground coal mines [18]. In 2022, Xie, Xiong, and Chen used CFD to model the movement of gases along roadways of non-metallic mines in an attempt to derive migration laws [19]. The body of work involving CFD for questions of mine ventilation, especially for mining health and safety is expansive.…”

Hazardous Area Reconstruction and Law Analysis of Coal Spontaneous Combustion and Gas Coupling Disasters in Goaf Based on DEM-CFD

“…In China, the energy shortage problem is still serious, and coal is still the main part supporting the country’s energy structure. − Coal spontaneous combustion and gas coupling disasters are the highest percentage of serious accidents in coal mines and the most serious disasters caused by them, which seriously threaten the environment and the safety of workers’ lives. , Air leakage will cause spontaneous combustion of residual coal in goaf and affect gas migration in goaf. When the combustion temperature of residual coal increases to the ignition temperature of gas, gas can be ignited and developed into gas explosion. , According to statistics, gas explosion accidents caused by spontaneous combustion of residual coal have occurred in China, India, Poland, Australia, and other countries around the world, causing huge casualties and economic losses. − In recent years, with the exhaustion of shallow coal resources, deep coal mining has become the new normal of coal resources mining in China. − As the mining depth gradually deepens, the observable in situ stress, ground temperature, gas content, and gas pressure also increase, which makes the coupling disasters represented by coal spontaneous combustion and gas in fully mechanized caving goaf more frequent and serious. − Therefore, the prevention and control of such coupling disasters as well as the early warning researches are of great importance to ensure the safety of the coal mining process.…”

“…When the combustion temperature of residual coal increases to the ignition temperature of gas, gas can be ignited and developed into gas explosion. 7 , 54 According to statistics, gas explosion accidents caused by spontaneous combustion of residual coal have occurred in China, India, Poland, Australia, and other countries around the world, causing huge casualties and economic losses. 8 − 11 In recent years, with the exhaustion of shallow coal resources, deep coal mining has become the new normal of coal resources mining in China.…”

Study on the Dynamic Stability of an Underground Engineering Rock Mass with a Fault-Slip Seismic Source: Case Study of a URL Exploration Tunnel

“…On one hand, the stability of URLs is affected by the mechanical properties of the rock mass and the stress state of the surrounding rock. On the other hand, radon is a radionuclide that is harmful to human bodies and can be found in URLs, and the development of cracks in the failure of surrounding rock provides favorable conditions for the abnormal release of radon gas [14][15][16]. Therefore, studying the stability of the surrounding rock under dynamic disturbance in underground laboratories is of great significance.…”