回采工作面采空区瓦斯封存量计算模型研究

Study on calculation model of goaf gas sequestration of stope face

为准确计算煤炭开采过程中回采工作面采空区瓦斯封存量,基于采空区上覆煤岩层运移及裂隙分布发育规律,分析回采工作面采空区瓦斯封存量主要影响因素,建立回采工作面采空区瓦斯封存量计算模型,并对其进行计算验证。结果表明:回采工作面采空区封存瓦斯量主要受煤岩瓦斯赋存地质条件和开采技术条件2个方面因素影响;根据采空区上覆煤岩层垮落规律,采空区瓦斯封存量可分为压实稳定区瓦斯封存量、自然堆积区瓦斯封存量、承压影响区瓦斯封存量和采空区内遗煤瓦斯残存量4部分;用建立的模型计算某煤矿N2413综采工作面采空区瓦斯封存量,计算结果与实际结果之间相差13.5%,误差在合理范围之内。

To calculate the gas sequestration of stope face during the process of coal mining accurately,based on the regularity of overlying coal＇s and rock seams＇ migration in stope and fracture＇s distribution and development,main factors influencing of goaf gas sequestration were analyzed,then a gas sequestration＇s calculation model of goaf in stope face was built and checked. The results show that goaf gas sequestration of stope face is mainly affected by gas occurrence＇s geological conditions and mining technical conditions,that according to the overlying coal and rock＇s roof caving regularity above the goaf,goaf gas sequestration can be divided into four parts,namely,steady compaction area＇s gas sequestration,natural accumulation area＇s gas sequestration,pressure affected gas sequestration and residual coal＇s gas sequestration in goaf,and that by calculating the gas sequestration of working face goaf N2413 for a certain coal mine,the difference between calculation results and the actual results is 13. 5%,and the error is within a reasonable range.