基于单井空间形态拓扑分析的煤层气垂直井开发井网优化研究

Well placement concerns to the coalbed methane(CBM) productivity and investment profit in the large-scale commercial development stage. Based on the CBM geology and mathematical geology theories, drawing on the advanced concept of oil reservoir, an optimization of well placement for a large-scale CBM exploitation will be conducted through the numerical simulations. Firstly, key parameters which control the yield of the reservoir will be filter through a sensibility analysis. And a single factor reservoir model will be built to present the spatial form of a well in draining then. Meanwhile, a hybrid model of optimization algorithm mixing topology analysis will be established to make the well-bore locations evolution and optimum. Finally, an efficiency assessment will be operated to compare the simulated CBM yields of different well placement plans and the most efficient well placement plan will be settle down.

国内煤层气开发正在向商业化转型，由于关系到投资效益，井网布设方案对煤层气采收率和投资收益均有很大影响。基于煤层气地质学和数学地质理论，借鉴常规油气规模化开发井网优化理念，对煤层气规模化开发阶段的井网优化技术进行研究。对影响单井产能的储层参数进行敏感性分析，选取关键参数建立单井排采储层空间形态模型，基于优化算法混合拓扑分析，对井距和孔位进行确定，运用储层模拟对优化后的布井方案进行产能预测，结合基于数据包络分析的经济评价思想对优化后的井网进行投资期望排序，选出最佳布井方案。

本项目以沁水盆地煤层气开发示范区潘庄区块为研究区，围绕煤层气地面垂直井规模化开发时的布井方案优化问题开展研究。在煤层气地质理论指导下，以煤层气储层数值模拟为主要技术手段，依据构造地质、水文地质条件和煤层空间分布规律划分布井单元，分析不同布井单元的产能敏感参数，进而分析单井排采储层空间形态变化特征和产能受控机理，在以最大化财务净现值为目标的驱动下使用拓扑分析、坡度分析等技术基于粒子群优化算法建立了面向开发区块尺度的垂直井井网优化模型及优化流程，最后通过研究区的实际数据验证了优化模型和流程的可行性，为实际开发提供了优化建议参考。