摘要
针对河南油田老区块酸化增注效果逐渐变差的问题,以长链二元羧酸和碳酸盐为主剂开展了自生二氧化碳深部解堵技术研究。在评价回注污水、模拟油对多段岩心的水相渗透率影响的基础上,研究了自生CO2对无机物、有机物的解堵效果,以及CO2与酸液配合使用顺序对长岩心渗透率的影响。结果表明,污染物注入量越大,水相渗透率越低,注入10PV以后,渗透率降低30%～70%;注入自生CO2段塞可以有效清除有机物的堵塞,使水相渗透率提高3～4倍。CO2与酸液配合使用可大幅提高渗流能力和有效作用深度,对重复酸化的储层也具有较好的增注效果。还讨论了酸与CO2的注入顺序所适应的条件。
In allusion to the problem of worsening well stimulations in the eastern maturing wellblocks of Henan Oilfield,deep plug removal technology with CO2 produced by the reaction of dicarboxylic acid and carbonate in formation and acidization were studied.On the base of evaluation of plugging ability of injecting sewage and simulation oil to reservoir,the effect of CO2 produced in formation and injecting sequence of CO2 and acid on plug removal was studied.The results show that water permeability of series core reduces by 30%～70% after injecting fluids over 10 pore volume,inorganic and organic plugging can be removed by CO2 injection,especially oil plugging can be removed to enhance water permeability to 3～4 times that of oil.CO2 used with acid can improve permeability of low-permeability reservoir after reacidizing and deep acidizing.In addition,suitable condition of CO2 and acid is discussed.
出处
《石油天然气学报》
CAS
CSCD
北大核心
2010年第5期21-24,59,共5页
Journal of Oil and Gas Technology
基金
国家"973"规划项目(G19990225)
关键词
增注技术
酸化
解堵
CO2
络合表面活性剂
低渗储层
stimulation
carbon dioxide
chelating surfactant
acidizing
low permeability reservoir
