Oblique Borehole Goaf Governance Roof High Technology Research

Coal and gas outburst is a variety of more serious coal mine disaster, in which the upper corner gob gas accumulation caused by coal and gas outburst accident is a common issue facing mine, To find a suitable and economically viable solution, a large number of coal mine workers and experts after years of research and practice, many promising theories and measures also will emerge out-roadway drainage, drainage pipes embedded, surface drilling drainage, roof level oblique drilling drainage and so on. In the study of Huaibei Mining Group Luling Coal mining face trial after trial to resolve mining Gob gas accumulation in upper corner issues and expectations similar geological mining environment gob gas drainage upper corner provide a valuable reference. In this paper, elastic mechanics, fluid mechanics, rock mechanics and other basic theory, through theoretical analysis, numerical simulation and field test visits and other avenues of research, more comprehensive study of Luling Coal II817face after mining overburden crack belt range, fissures Nevas flow with regularity and drainage effects, results can gob gas drainage upper corner provide an important reference.On Luling Coal II817Coal Face Overlying rock stress state (face orientation) analysis, results in a protective layer on the amount of stress and sinking expression, in this theoretical analysis basis, combined with empirical formulas and field measured data, determine II817face overlying highly fractured zone of rock, which for the next high drainage drilling field arrangement provides the best theoretical position.In contrast to the various governance gob gas accumulation in upper corner of the advantages and disadvantages of measures, combined with the specific test mining face geology and mining methods and Huaibei Mining Group, the general requirements for gas control, and ultimately determine the II817goaf District corner gas control subjects using high oblique roof drainage drilling method to complete the research projects. Mining face in the test at regular intervals from the advancing direction of arrangement of a high drill field, high drilling parameters of various parameters are: effective length of about100m drilling, drilling field spacing of70m, borehole pressure stubble distance20m, each drill field was semi-fan arrangement of six distribution drilling, hole spacing0.3m, from floor1.0m. By arrangement with the highs in the fissure drill field opposite direction to the direction of construction and mining of high Borehole, test mining face in promoting the process of mining, surface mining of the test corner gas concentrations and gas pumping Borehole mining scalar governance indicators to examine other gas extraction results. For the parameters optimized drilling oblique roof level to inspect drainage effect,Ⅱ817-1Face From November2011began mining, from November2011to March2012on the roof level of bias drilling drainage results were studied. Drainage pipe Lu Wasi volume fraction gradually increased from3.6%to13.8%floating, mean steady at8.3percent, the largest drainage volume fraction of13.8%, the largest pure gas drainage flow6.6m3/min. Face drainage volume higher than90%, with working to eliminate the phenomenon of gas gauge, to achieve good control effect. It can be that after extraction of the lower reaches of the effective mining Gob upper corner gas accumulation purposes.