浅谈涪陵页岩气田加密调整效果评价及影响因素
2021-07-11陈忠米瑛
陈忠 米瑛



摘 要:涪陵页岩气田焦石坝区块实施了40口加密调整井,均获得了工业气流,但测试产量和压力较老井明显偏低,同时,加密井压裂期间,部分小井距老井出现了干扰现象,对老井的生产效果产生了正面或者负面的影响, 因此,文章旨在通过对比加密井与老井的生产特征,评价加密井的开发效果,认识其生产规律,探讨影响加密井开发效果的影响因素,从而提出改进措施,提高加密井产能以及井组最终采收率。
关键词:加密井;产量;压力;衰竭区;加密时机;投球暂堵
中图分类号:TE243 文献标识码:A 文章编号:1001-5922(2021)04-0174-06
Abstract:In Fuling Shale Gas Field, has implemented 40 infill adjustment Wells, all of which have obtained industrial flow. But the test production and pressure are obviously lower than the old Wells, at the same time, during the infill well fracturing, some small well spacing are disturbed from old well, it has a positive or negative effect on the production effect of the old well. Therefore, In this paper, the production characteristics of infilled wells and old wells are compared, evaluate the development effect of infill well, understand the law of production. Discuss the influencing factors that affect the development effect of infill wells, and propose improvement measures to increase the productivity of infill wells and the final recovery rate of well groups.
Key words:infill well, output, pressure, depleted area, infill time, temporary blockage of pitching
涪陵页岩气田为国内首个投入商业开发的页岩气田,焦石坝区块开发层系为五峰-龙马溪组,含气页岩段可划分为上、下部两套气层,上部气层厚约57m,下部气层厚40m左右。前期,下部气层为涪陵页岩气田主力气层,埋深2200~2800m,平均孔隙度5.96%,平均TOC值3.13%,脆性矿物含量68%,为典型的优质页岩气储层。焦石坝区块下部气层主要以丛式布井模式1台4井或1台6井为主,井距约600m,水平段长1500m,通过大型水力压裂改造后,实现了商业开发。目前,涪陵页岩气田焦石坝一期预测采收率12.6%,远低于国外页岩气田采收率(20%)[1],因此,焦石坝区块剩余儲量大、储量动用不充分、开发调整潜力大,可通过加密调整提高区块的最终采收率。
2019年底,焦石坝区块下部气层已实施加密评价井40口,已投入试采。加密试验井的实施后,加密井压裂期间对老井产生井间干扰,老井复产后生产效果发生了变化,同时,加密井的生产效果也存在差异。……
