非均质性气藏储气库布井方式优化设计

Optimization Design of Well Pattern in Heterogeneous Gas Storage

储气库布井方式与常规气田开发有很大不同,在相同的投资条件下,气田开发布井方式追求气田采收率最大化,而储气库布井方式追求储气库在一个采气周期(3~4月)内工作气量的最大化;特别是利用非均质性气藏建设的储气库,不同区域气井产气能力差异性较大,不宜采用一套井网。以苏A储气库为例,将建库区划分为高、低渗透两个区域,分别论证了不同区域气井采气能力以及区域工作气量随采气井数变化规律,同时,提出了一种基于工作气量最大化的非均匀布井方法,确定了高渗区、低渗区合理的井网密度。结果表明,当储气库总井为11口时,采用非均匀布井方式,高渗区井网密度为1.7口/km^2,低渗区井网密度为0.38口/km^2,储气库工作气量较均匀布井提高0.99×10^8m^3,提高幅度14.6%。

Gas storage well pattern design is very different from conventional gas field well pattern design.Under the same investment conditions,the conventional gas field well network design pursues the maximum recovery of gas field,while gas storage well network design pursues maximum working gas volume in one gas production cycle(3~4 months).Because of the great different of gas production capacity in different areas,one set of well pattern is not suitable for gas storage wells built on heterogeneous reservoirs.Taking Su A gas storage as an example,the area for gas storage network is divided into areas of high permeability and low permeability.We analyze the production capacity of gas wells in the two areas and the regional working gas volume variation with the number of gas wells.And we propose a non-uniform well pattern based on the maximization of working gas volume,and determine the reasonable well pattern density in high permeability zone and low permeability zone.When there are 11 wells in the gas storage,with non-uniform well pattern,the well pattern density in the high-permeability area is 1.7 wells/km^2,and that in the low-permeability area is 0.38 wells/km^2.The working gas volume of gas storage will be increased by 0.99×10^8 m^3 than that of uniform well pattern.