改进的考虑复合影响低渗气藏气井产能方程  

IMPROVED WELL-PRODUCTIVITY EQUATION CONSIDERING COMPOUND INFLUENCE FOR LOW-PERMEABILITY GAS RESERVOIRS

作　　者：王永胜[1] 陈杜娟[1] 肖青波 纪成[1] 王怀龙[1] 

机构地区：[1]西南石油大学石油工程学院

出　　处：《天然气勘探与开发》2014年第3期45-48,56,共5页Natural Gas Exploration and Development

摘　　要：针对低渗气藏的渗流特征,以气体渗流时启动压力、高速非达西效应为依据,建立了考虑应力敏感与滑脱效应复合影响的低渗气藏气井产能方程,并基于设定的不同形式拟压力和天然气烃类体系在地层温度下黏度与压缩因子的乘积与压力的关系曲线,对不同压力区间拟压降与启动压力项的计算公式进行了推导,给出了产能方程的细化计算方式,对低渗气藏气井产能规律进行了研究。结果表明:采用改进的不同压力区间拟压力不同简化形式的细化计算方式具有更高的计算和分析预测精度,通常迭代或近似计算方式所计算的结果使滑脱效应对气井产能的影响偏大;应力敏感使气井产能减少、滑脱效应使气井产能增加,当压力较高时,应力敏感和滑脱效应对气井产量影响较弱,随着压力降低其影响逐渐增强。Aimed at percolation features in some low-permeability gas reservoirs,according to the start-up pressure and high-speed non-Darcy effect while gas percolating,this paper establishes a productivity equation considering compound influence of both stress sensitivity and slippage effect.Based on the relation curve of the product and pressure of viscosity and compressibility factor of pseudopressure and hydrocarbon system in different forms under formation-temperature condition,the formulas to calculate pseudopressure drop and start-up pressure term in various pressure were derived,a fine calculation for the productivity equation was obtained,and the productivity rule was studied.Result shows that:(1)the fine calculation has higher accuracy than the iterative or approximate methods which cause larger influence of slippage effect on productivity;(2)stress sensitivity decreases productivity,whereas slippage effect may increase it,the influence of both stress sensitivity and slippage effect is smaller at higher pressure and increases with pressure drop.

关 键 词：低渗气藏 拟压力 应力敏感 滑脱效应 细化计算 产能方程 

分 类 号：TE328[石油与天然气工程—油气田开发工程]