低瓦斯矿井自燃“三带”划分及模拟

通过划分采空区自燃"三带",可以确定出工作面对自燃防治有利的最低月推进度。目前采空区自燃"三带"的划分还没有形成统一的标准。根据棋盘井煤矿0912工作面实际情况,沿采空区布置了4个测点,测定出采空区气体各组分变化规律,确定了低瓦斯矿井工作面采空区自燃"三带"的划分新方法。并利用Fluent软件,对采空区自燃"三带"进行了数值模拟。结果表明:0912工作面采空区自燃"三带"的范围为:散热带<24 m,自燃带24～113 m,窒息带>113m。为了保证在最短的自然发火期内,能将采空区内遗煤甩到自燃"三带"的窒息带以内,工作面最低月推进度应≥68 m。

Numerical Simulation and Division of Spontaneous Combustion "Three-Zone" in Low Gas Mine

The minimum monthly advancing degree which is beneficial to prevention and control on spontaneous combustion is identified by dividing spontaneous combustion "three-zone" of gob.At present,the division standard of gob spontaneous combustion "three-zone" has not been formed.According to practical situation of 0912 working face in Qipanjing coal mine,four measurement points are arranged along the gob.The new method of dividing spontaneous combustion "three-zone" of gob in low gas mine is determined by measuring the changing laws of gas components of gob.Fluent software is applied to simulate the spontaneous combustion "three-zone" of gob.The result shows that the cooling zone is less than 24 m,the spontaneous fire zone is from 24 m to 113 m,and the suffocation zone is more than 113 m.In order to take the residual coal of gob to the suffocation zone in the shortest spontaneous combustion period,the minimum monthly advancing degree should exceed 68 m.