桥口油田注水压力升高原因与治理措施  

The Reasons of Increase in Water Injectivity Pressure and Preventative and Remedial Measures at Qiaoko Oil Field in Zhongyuan

作　　者：程宝生[1] 高瑞民[1] 刘淑萍[1] 

机构地区：[1]中国石化中原油田分公司采油工程技术研究院,河南濮阳457001

出　　处：《油田化学》2002年第3期233-236,292,共5页Oilfield Chemistry

摘　　要：中原桥口油田注水压力高 ,30 %以上注水井欠注。基于该砂岩油藏特性及开发状况 ,通过储层岩心流动、污染和解堵实验 ,发现注水压力升高的原因 ,一是模拟地层温度下 (95℃ )地层水和注入水产生夹带CaCO3 的CaSO4垢 ,垢沉积堵塞注水井近井地带 ,二是频繁的调剖、堵水作业封堵了高渗通道 ,油水井连通性变差 ,低渗透层也受到伤害 ,超细水泥 /膨润土污染后的低渗岩心伤害不易恢复 ;提出的综合治理措施如下 :①注水初期对注水井进行粘土稳定处理 ,地层伤害后可注活性水改善渗透率 ,严格控制注水水质 (提出了包括表面和界面张力在内的 6条水质水性标准 ) ;②注水方式合理化 ,注水井井距以 2 5 0～ 30 0m为宜 ,注水压力 <35MPa ,注水强度≤ 4 .80m3 /m·d ;③高效螯合有机复合缓速酸解除岩心伤害的效果最好 ,盐酸和胶束酸略有效果 ,土酸有反效果 ;④用柴油携带的超细纳米活性聚硅粉在 1口井试用 ,增注降压效果很好 。The water injection pressure is high and more than 30% of wells is underquoted in injectivity rate at Qiaokou oil field, Zhongyuan. A series of experiments on reservoir flow, contamination, and blockage removal are performed and disscussed on the basis of reservoir characteristics and development status. It is shown that the reasons of water injection pressure raise are originated from: ① inorganic precipitates in the near bore zones of injection wells as the formation and injection waters create CaSO 4 scale admixtured with a little CaCO 3 at simulating reservoir temperature (95℃) and ②frequent profile modifying and water plugging treatments performed in the past which lead to plugging high permeable passages, to reducing connectivity between injection and production wells and to low permeable zone damage in some extent, the permeability damage in low permeable zones caused by an ultrafine cement/bentonite slurry is hardly recoverable. Some preventative and redemial measures to be undertaken are suggested as follows: ① to treate the new injection wells for clay stabilization, to use surfactant solution to improve the permeability demaged; ② to rationalize water injection scheme with injection well spacings 250-300 m, injection pressure <35 MPa and injection intensity ≤4.80 m 3/m·d; ③ to use strongly chelating combinational organic acidizing fluids to remove reservoir damage while hydrochloric and micellar acids are only slightly effective and negative effect obtained with mud acid; ④ to use ultrafine nanometric activated polysilicon powder carried by diesel oil, with which significant enhancement in waler injection volume and decrease in injection pressure are observed in trial use in one well and some pilot tests are to be performed.

关 键 词：桥口油田 注水压力 升高原因 治理措施 注水井 地层伤害 解堵剂 酸化液 中原桥口油田 

分 类 号：TE357.6[石油与天然气工程—油气田开发工程] TE258