新型抗高温高密度暂堵凝胶的室内评价

Laboratory evaluation of a novel high-temperature andhigh-density temporary plugging resistant gel

评价了一种新型抗高温高密度暂堵凝胶。结果表明,采用无固相复合盐加重,凝胶密度可在1.1~1.75 g/cm^(3)之间调节;抗温大于180℃,180℃静恒温15 d仍可保持良好的凝胶状态。封堵实验表明,凝胶能挤入模拟孔隙性地层的20~30目砂床中,起到防漏堵漏作用。在10 mD的裂缝岩芯中暂堵深度70~80 mm,其承压能力大于5 MPa;凝胶所形成的封堵堵塞,用破胶剂可破胶解堵。破胶后残液粘度低于5 mPa.s,残渣含量1.2%。破胶返排后,岩芯渗透率恢复率达93%,用于完井防漏堵漏,对储层具有低伤害特性。

A new type of high temperature and high density temporary plugging resistant gel was evaluated The result shows that the gel density can be adjusted from 1.1 to 1.75 g/cm^(3) by adding solid-free compound salt,and the gel state can be kept well even when the temperature resistance is higher than 180℃ and the static temperature is constant for 15 d at 180℃.The plugging experiment shows that the gel can be squeezed into the sand bed of 20~30 mesh in the simulated porous formation to prevent leakage and plugging.The temporary plugging depth of 10 mD fracture core is 70~80 mm,and its bearing capacity is more than 5 MPa.The viscosity of the residual solution is less than 5 mPa·s,and the residue is 1.2%.The permeability recovery rate of core is 93% after flowing back,which is used for completion,lost circulation and plugging,and has low damage to reservoir.