Jiang Fuliang

Optimization Study of Ventilation Parameters in Roadway Type Stope Based on Fluent Software

The blasting method is generally used in non-coal mine underground mining activity. However, blasting operations will result in massive release of several toxic and harmful gases, and these gases are of high concentration and difficult to exhaust as they can be rapidly spread and fully distributed in confined spaces, like stope and roadway, within a short time. In this paper, the Fluent software is used to analyze the distribution and diffusion regularities of those blast-induced gases. In order to facilitate the study, only CO is considered. The results indicate that with the increase of wind velocity in air inlet from 0.25 m/s to 4 m/s, the rate of CO concentration drop in the roadway type stope presents a linear tendency. The CO concentration after ventilating with wind velocity of 0.5 m/s is basically in line with the Chinese national safety standard, while CO concentrations in return air corner of the stope are still beyond the safety standards limit. The CO concentration can meet the standards requirement when the wind velocity is within the range of 1 m/s to 4 m/s, and the drop rates of CO concentration at 3 m/s and 4 m/s have little difference. On the basis of comprehensive analysis, the wind velocity in air inlet should be greater than 0.5 m/s, and less than 1 m/s.

The Optimization of Forced Ventilation Parameters on Blind Roadway Based on Fluent Numerical Simulation

In view of the fact that toxic and harmful gases are not easily discharged after blasting on the mining face of blind roadway in underground mine, it is necessary to optimize the forced ventilation parameters of this kind roadway. Taking a Fluorite mine as example, the distribution and diffusion law of toxic and harmful gases after blasting were analyzed by using Fluent software through the numerical simulation of component transportation. Besides, the numerical simulation was carried out to study some optimum conditions, such as design of the fan outlet, diameter of the air duct and magnitude of the wind speed. The study results indicates that: the best distance between the fan and digging surface is about 10m; the fan diameter should be no more than 400mm; the wind speed of the fan outlet should be kept within the range between 8m/s to 10m/s. The above conclusions can provide reference and basis for technical renovation of the mine ventilation.