Study On Coal Bed Methane Desorption Characteristics Of Yan’an Formation In Southern Ordos

Ordos is one of China’s major coal accumulation basin, which contains the amount ofenergy resources in a large proportion of the energy resources in the country, it is of low rankcoal CBM exploration of key areas. However, for a long low rank CBM exploration anddevelopment of the industry is relatively weak. With the demand for coal mining safety, cleanenergy shortages, environmental, the demand for low-rank coal bed methane extractionincreased. Binchang-huangling of Southern Ordos study area for the entire target layerJurassic Ordos CBM exploration and development has an important guiding significance.This paper mainly through industrial analysis, coal analysis, nitrogen adsorption,scanning electron microscopy, mercury experiments and different temperature points methaneadsorption/desorption experiments for the Yan’an Formation coal layer Dafosi4#coal, Dafosiup of4coal and Huangling2#coal, performs calculations isosteric heat, extreme heat ofadsorption, thermal analysis of low rank CBM mechanical characteristics. According to theresults that thermodynamic characteristics studies of Yan’an Formation CBM desorption.The results show that the target region is CY. It belongs to the low rank coal, its poreholes, hole, large specific surface area, it is conducive to the adsorption of methane. In anon-critical state, methane-coal matrix adsorption negatively correlated with temperature anddesorption positively correlated with temperature. As the pressure drop the desorption tofurther enhance. The difference is caused by the the desorption hysteresis Thermodynamicessence which the heat of the adsorption process and the desorption process.