一种基于长效储层保护的新型有机胺完井液

A New Organic Amine Completion Fluid for Long-term Reservoir Protection

针对乌干达某油田储层黏土矿物含量高,完井液在井底与储层接触时间过长,易造成储层损害的问题,基于完井液的抑制性实验确定有机胺加量比例和储层保护性能实验验证优选完井液的长效储层保护的作用的方法,提出了一种加入有机胺(PF–NETROL)的新型完井液。结果表明,现场不同含量有机胺(PF–NETROL)的完井液作用到膨润土后,放置1 d之后的防膨率分别为85.42%和94.21%,加入有机胺之后防膨效果较好;其中,加量为2%时的完井液体系在放置90 d后该完井液体系的防膨率仍大于90%,一直对膨润土保持着较好的抑制性;并且该体系在0~30 d内完井液对储层的危害最小,超过30 d之后开始对储层有一定程度的污染,在30 d后污染速度由缓慢增加到快速上升。因此,优选加量为2%有机胺(PF–NETROL)的完井液作为乌干达该油田的完井液体系,并建议在实际作业中采用每30 d更换、补充完井液的方式来保证完井液的性能,为能够进行长期作业提供保障。研究提出的新型有机胺(PF–NETROL)完井液配方可为长效完井液储层保护提供参考和借鉴。

The Ugandan oil field is characteristic of high content of clay minerals in the reservoir;the long time contact of the completion fluid and the reservoir at the bottom of the well can damage the reservoir.In order to handle these problems,a new type of completion fluid with organic amine(PF–NETROL)is elaborated in this research.The inhibition test of the completion fluid is first of all utilized to determine the dosage ratio of organic amine in the completion fluid,then the reservoir protection performance test is conducted to verify the long-term effect of the optimized completion fluid on the reservoir protection.The experimental results showed that the anti-swelling rate that was initially 85.42%increased to 94.21%after being placed for one day in the completion fluid with different content of organic amine(PF–NETROL)proving that the anti-swelling effect with the organic amine is good;the anti-swelling rate of the completion fluid system with a dosage of 2%is still more than 90%after 90 d of placement and it maintained a good inhibition on bentonite;in addition,the completion fluid of the system has the least damage to the reservoir within 0~30 d and the pollution rate increased quickly after 30 d.The completion fluid with a dosage of 2%organic amine(PF–NETROL)is preferred as the completion fluid system of the oilfield in Uganda;therefore it is recommended to replace and supplement the completion fluid every 30 d in the actual operation to ensure the performance of the completion fluid and provide guarantee for long-term operation.The new organic amine(PF–NETROL)completion fluid formula proposed in this paper can play referrable effect on long-term completion fluid reservoir protection.