Technical Study On Leading Exploitation Underground Coal Bed Methane In Coal Mine-scale

Drilling long borehole down the seam is a valid method of mining gas from mining-coal bed, which is an important technology to deal with mine gas calamity and also a new approach of mining coal bed methane. Firstly, this dissertation aims to improve the depth of drilling long borehole down the seam, exploring successfully the technics and skills that are used to improve the depth of drilling long borehole. Additionally, it studies deeply technics of mining coal bed methane by drilling borehole down the seam and gets the anticipative achievements.The dissertation dissertates the reservoir and influential factors, elucidating evaluation concern and means of coal bed methane. It analyzes the factors of affecting the depth of drilling long borehole down the seam, bringing up the approach of drilling dust extraction with wind-force instead of water-force; the formulae of calculating parameters about drilling dust extraction with wind-force are created and theoretical analysis on valid mining-radius. What's more, the dissertation finds the relation between the depth of drilling borehole and wind pressure by on-the-spot survey, designing drilling tools that can enhance the directional functions.This dissertation studies the technology and techincs of mining coal bed methane by drilling borehole down the seam, researching the relation between negative-pressure and quantity of flow. It compares the mining results under different diameters and lengths drilling boreholes. Besides, elaborate technology economy compare about the technics and technology of mining coal bed methane by drilling borehole down and cross the seam is carried out.