Research and Application of Mobile Gas-Extraction Technology on the Upper Corner of Working Face

Abstract

Aiming at solving the existing problems of gas treatments on the upper corner presently,poor drainage effect and the high cost of engineering quantity included , gas drag pipe drainage technology and processes on the upper corner is designed.It can make the drainage point matching working face advance speed, realize continuous drainage points in space.And research on the drainage parameters is the foundation of the successful implementation of drag drainage pipe technology.It introduced Brinkman equation, Fick's law of diffusion and gas diffusion translational equations to describe the behavior of gas flow diffusion ,established the migration and diffusion gas flow model at working face ,and the two models are combined in a unified flow field., establishing a coupling model of multi-physics gas flow at the working face.And the model is solved by fluent to determine the optimal parameters of towing pipe drainage.Finally,it makes a practical application and testing results in Changcun coal mine working face N3-8. The results show that gas drag pipe drainage technology is conducing to governing on the accumulation of corner gas,and the gas concentration on the upper corner down to 1%,determining the best the drainage location for distance back plane 2.4m, an inclined direction distance back to the wind tunnel 1.6m, along strike depth to goaf 15m .Taking measures to block the upper corner,which can improve the drainage concentration,and make the concentration of gas on the upper corner down to 0.6%.The application of field basically agrees with the simulation results,so pipe drainage technology has feasibility and good applicability of top corner gas drag