超低渗油藏低含水阶段氮气泡沫驱注入参数设计

Injection parameter design of nitrogen foam flooding in low water cut stage of ultra-low permeability reservoir

针对延长油田SJH区块大部分低含水井地层压力低、能量供给不足等特点,针对性提出了氮气泡沫驱注入参数设计方法。当水源充足时,设计每个注入周期注水段塞0.05HCPV、注气段塞0.01PV,充分发挥注入水对补充地层能量的作用,注入气段塞对水窜具有抑制作用;当水源不足时,每个注入周期推荐注气段塞0.05HCPV、注水段塞0.01HCPV,充分发挥注入气对补充地层能量的作用,注入水段塞对气窜具有抑制作用;当水源不足、且注入井注入压力较高时,每个注入周期推荐注气段塞0.05HCPV、注泡沫液段塞0.01HCPV。根据上述方法及油藏实际参数,对SJH区块低含水区进行了泡沫驱方案设计,预测实施泡沫驱效果良好。

Aiming at the characteristics of low formation pressure and insufficient energy supply in SJH block of Yanchang Oilfield,a nitrogen foam flooding injection parameter design method was proposed.When the water source is sufficient,the injection slug of 0.05HCPV and gas slug of 0.01PV in each injection cycle are designed to give full play to the role of injected water in replenishing formation energy,and the injection gas slug can inhibit water channeling.When the water source is insufficient,0.05HCPV of gas injection slug and 0.01HCPV of water injection slug are recommended for each injection cycle to give full play to the role of injected gas in replenishing formation energy,and the injected water slug can inhibit gas channelling.When the water supply is insufficient and the injection well pressure is high,0.05HCPV of gas slug and 0.01HCPV of foam slug are recommended for each injection cycle.According to the above methods and the actual parameters of the reservoir,the foam flooding scheme was designed for the low water cut area of SJH block,and the effect of foam flooding was predicted to be good.