南海油田惠州潜山裂缝性凝析油气藏控水实验

为建立潜山裂缝性凝析油气藏优化控水开发的模式,以南海油田惠州潜山裂缝性凝析油气藏H2-3井参数为基础,设计了气藏控水物理模拟实验,通过非均质储集层设计、实验参数设计、裂缝参数设计和控水实验方案设计,完成了弹性开采实验、连续封隔体控水实验、水敏凝胶控水实验、变密度筛管控水实验和变密度筛管+连续封隔体组合控水实验5组控水实验,对不同方案的控水效果进行了对比,并分析了各个控水工艺的机理。在此基础上,结合数值模拟进行验证,提出了气藏控水开采方案：气藏底水开采初期,水体推进为渐进式上升,中—后期为锥进式发展,后期底水一旦接触储集层裂缝,水体呈突进式侵入;各种方案的控水效果差异较为明显,连续封隔体和水敏凝胶在气井采气期对底水控制作用不明显,变密度筛管在采气初期控水效果较好,但气井见水后无法避免水窜风险。变密度筛管+连续封隔体组合控水效果较好,改变了底水锥进效应,与弹性开采相比,无水采气时间增加了8.84%,总采气时间增加了13.70%,采气量提高了10.40%。

Water Control Experiments in Huizhou Buried-Hill Fractured Condensate Reservoirs in Nanhai Oilfield

In order to establish an optimal water control model for buried-hill fractured condensate reservoirs, based on the parameters from Well H2-3 in Huizhou buried-hill fractured condensate reservoirs in Nanhai oilfield, a physical simulation experiment for water control in gas reservoirs was designed. Through heterogeneous reservoir design, experiment parameter design, fracture parameter design and water control experiment scheme design, 5 groups of water control experiments were conducted, including elastic production experiment, continuous packer experiment, water-sensitive gel experiment, variable density screen experiment and variable density screen + continuous packer experiment. Then, their water control effects were compared, and water control mechanism of each experiment was analyzed. On this basis, verification was performed by using numerical simulation, and the water control development scheme of gas reservoir was given. The results show that in the stage of early development driven by bottom water of gas reservoir, the water body advances in a gradual manner; in the middle-late stage, the water body advances in a conical manner; and in the late stage, once the bottom water contacts the fractures in the reservoir, the water body will intrude in a sudden manner. The water control effects of the five schemes are different. The schemes of continuous packer and water-sensitive gel exhibit unobvious water control effects in the gas production stage, and the scheme of variable density screen demonstrates good water control effect in the early gas production stage, but fails to avoid the risk of water channeling after water breakthrough in a gas well. The scheme of variable density screen + continuous packer shows good water control effect, with the bottom water coning effect changed, and with the water-free gas production period, total gas production period and gas production volume increased by 8.84%, 13.70% and 10.40%, respectively as compared with the scheme of elastic production.