Evaluation Of Coalbed Methane Reservoir Characterizations And Block Division In Lu’an Mining Area

Coalbed methane(CBM) resources are very abundant in Lu’an mining area. The major mining coalbed 3# is tested with high gas content, and the maximum gas content reaches 23.33m3/t. The large GIP indicates a bright future of CBM development in Luan Mining Area. However, due to the low pressure, low permeability and low gas saturation characteristics in coal 3#,an evaluation are very important for developing a better understanding of the reservoirs and for planning the development stritage.In this thesis, the most intense tectonic movement occurred in Yanshan period, in which the regional tectonic framework formed and largest gassy hydrocarbons generated and storaged in coal.Based on statistics and analyzed of the researvoir data of Lu’an coalbed No.3, it was found that tectonically deformed coal occurred cross over the region and varies in thickness largely. Cleats system are not well developed in the coalbed, and cleats filled with minerals observed through scanning electron microscopy, seriously affect the permeability of this region; by mercury curve, microporous and small hole large proportion, mesopore, large hole small-scale; gas content showed that higher in the western than in the eastern, mainly due to changes in burial depth control; reservoir pressure and reservoir pressure gradients are very low,is undervoltage reservoir, the main factors affecting the distribution of reservoir pressure is seam depth; penetration in the region is very low, average 0.037 m D. This low permeability, low pressure, low saturation reservoir characteristics of coalbed methane development must be with higher technical requirements of antireflection, and need to optimize the appropriate fracturing stimulation technology system.Based on Lu’an coal mine No.3 reservoir properties studied, then establishment of a Lu’an Mining coal-bed methane development block division and block based evaluation methods- "Quantitative+Qualitative" combination, Lu’an Mining have been divided into 24 CBM development units, and based on a favorable degree of preferred,sorting, then divided into four levels, the coalbed methane development most favorable units are 22 nd,10th,14 th,12th,13 th,7thunit.