Reducing external air leakage at the main ventilation unit of the mine

Abstract

Purpose. To increase the efficiency of mine ventilation by reducing external leaks through the ventilation shaft construction. To achieve this goal, it is necessary to solve the following tasks: - to analyse the existing methods for reducing external leaks through the ventilation shaft components; - consider the possibility of using a counteracting fan to unload the main fan from external leaks; - to establish the mutual influence of the main and counteracting fans during their joint operation; - to develop a methodology for determining the operating mode of the auxiliary fan in which external leaks are stopped in full. Methodology. To accomplish the set tasks, the analysis of the existing methods for combating external leaks in the main fan of the mine was carried out; a mathematical model was developed for controlling the ventilation modes of the main and auxiliary fans during their joint operation. Based on the mathematical model, the degree of mutual influence of the fans on each other was studied, a technique was developed for determining their mode, in which the mine jet in full volume enters the main fan, and external leaks are stopped by the auxiliary fan. Findings. A mathematical model for controlling mine ventilation and stopping external leaks in the ventilation shaft elements has been developed using the methods for planning industrial experiments; the degree of mutual influence of the fans on each other has been established; a method has been developed for determining the mode of their joint operation, in which the main fan is not loaded with external leaks. Originality. The degree of mutual influence of the main and auxiliary fans during their joint operation has been determined. The conditions are studied under which the mine jet enters the main fan, while external leaks occur to the auxiliary fan. Practical value. The studies conducted make it possible to separate external leaks from the main stream coming out from the mine, which increases the safety of work and reduces the cost of ventilating the mine.