The Study On Numerical Simulation And Development Scheme Of Coalbed Gas In Qin South Block

Coalbed methane is a new type of clean energy which was high efficient and energy saving. Developing and utilize coalbed methane has important significance to improve coal mine safety production, protect the atmospheric environment for human survival and make full use of clean energy. Coalbed methane is an unconventional natural gas. At present, the degree of its exploration and development is not high and lack of the reference materials in our country. In this paper, based on the standard of coalbed methane field development plan preparation, according to the field description, comprehensive analysis and economic indicators, we recommend the best development scheme of the coalbed methane in target block, which has important strategic significance in guiding the development of coal-bed gas in the future.On the foundation of the analysis of the geographical location, traffic and exploration drainage data of the coalbed methane reservoir in the target block, combine with the understanding of gas reservoir formation, structure, coal and coal seam characteristics, the coal reservoir description to design gas reservoir engineering parts. Gas reservoir engineering design mainly includes the reserves calculation, development mode selection, layer division, well network deployment and reasonable wells scheme determination and related content. Analysis the original gas characteristics and adsorption characteristics, calculate the critical desorption pressure, reservoir fracture porosity and initial gas saturation for the the next geological modeling. Use the volumetric method to determinate coalbed gas reservoir geological reserves. Forecast the recoverable reserves and recovery. Utilize five kinds of productivity prediction methods to predict the productivity of single well in order to determinate the reasonable productivity of vertical wells and U type well. Use the PETREL software to establish gas reservoir fine geologic model and transform the single porosity geological model into dual porosity geological model by using FLOGRID software. Through the combination of CMG and ECLIPSE 2011 numerical simulation software predict well pattern scheme. Based on historical high fitting precision design 15 sets scheme, among them there are 9 sets of vertical wells rectangular well pattern, 5 sets of equilateral triangle well pattern and a set of U type of wells and vertical wells. And ultimately determine the joint development of U type and vertical wells as the optimum plan.Based on the design of overall development plan, finally carries on the economic evaluation. And respectively carry out the sensitivity analysis with coal-bed methane prices, production, cost and investment as the uncertain factors to ensure the feasibility and economic benefits of the development plan.