煤在温度和压力综合影响下的吸附性能及气含量预测

The adsorption capability of coal under integrated influence of temperature and pressure and predicted of content quantity of coal bed gas

通过对有代表性煤样的副样进行不同温度等温吸附试验,在进行等温吸附实验前对煤样进行平衡水分处理,使煤样的水分含量接近原地煤的水分含量.研究发现,在等压条件下,煤吸附甲烷量随着温度的增加呈线性减少,相同温度,不同压力、不同煤样吸附量的减少量不相同.在温度和压力的综合作用下,在较低温度和压力区,压力对煤吸附能力的影响大于温度的影响,随着温度和压力的增加煤吸附甲烷量增大;在较高温度和压力区,温度对煤吸附能力的影响大于压力的影响,煤吸附甲烷量减少;煤变质不同,吸附量增大到吸附量减少的转折点不相同.建立了接近原地煤层气储集条件(包括温度、压力、水分、灰分、煤变质)综合影响下煤层气含量预测方法.该方法已被全国煤层气资源量计算应用.

It is made isothermal adsorption test of difference temperature for coal sample of representative. The equilibrium moisture processing of coal sample must be conducted before analysis, and the equilibrium moisture after processed is equivalent to the moistureholding capacity of coal and close to the moisture content in insitu coal. Research is discovered that the coal adsorption quantity are decreased with increasing temperatures under isotonic condition, same temperature, different pressure, the decrease quantity of different coal sample adsorption quantity is different. Affection of pressure is greater than temperature for coal adsorption under the integrated influence of temperatures and pressures in lowness temperature and pressure area, the adsorption quantity of coal are increased with temperature and pressure. Affection of temperature is greater than pressure for coal adsorption in higher temperature and pressure area, the adsorption quantity of coal are decreased. If coal metamorphose is different, turning point of adsorption quantity increase to decrease is different. The author sets up predicted method of coal bed gas content that is close to insitu storage condition of coal bed gas (include temperature, pressure, moisture, ash, coal metamorphose) in integrated influence, this method is used in forecast of resources quantity of coal bed gas.