氯化钙加重聚合物压裂液破胶技术研究  

Study on gel breaking technology of calcium chloride weighted polymer fracturing fluid

作　　者：刘源[1] 王丽伟[2] 庹维志 高莹[2] 陈庆[1] 徐敏杰[2] 李二鹏[1] LIU Yuan;WAND Liwei;TUO Weizhi;GAO Ying;CHEN Qing;XU Minjie;LI Erpeng(Research Institute of Petroleum Engineering,Tarim Oilfield Company,Xinjiang Korla 841000,China;Research Institute of Petroleum Exploration and Development,Beijing 100083,China)

机构地区：[1]中国石油塔里木油田分公司油气工程研究院,新疆库尔勒841000 [2]中国石油勘探开发研究院,北京100083

出　　处：《非常规油气》2021年第3期105-110,共6页Unconventional Oil & Gas

基　　金：国家科技重大专项“储层改造关键流体研发”(2017ZX05023003)。

摘　　要：为解决氯化钙加重聚合物压裂液的破胶难题,研发了专用氧化还原型破胶剂,并对破胶性能进行了评价。该破胶剂由氧化剂(主剂)和还原剂(辅剂)构成,在低温50℃以下,主剂分解出游离氧自由基的半衰期时间较长无法满足破胶需求,还原剂能够激活低温下氧化剂的分解反应,解决低温破胶难题。该破胶剂在水溶液中不产生SO^(2-)_(4),没有硫酸钙二次沉淀,也不出现凝胶柱现象,破胶彻底。该专用破胶剂在施工过程中缓慢释放,确保压裂施工顺利实施;破胶后粒径与常规胍胶压裂液相当,70%小于109.6μm,95%小于195.2μm;破胶后聚合物分子量为10万,破胶效果良好。In order to solve the gel breaking problem of calcium chloride weighted polymer fracturing fluid,a special redox type gel breaker was developed and the gel breaking performance was evaluated.The gel breaker is composed of an oxidizing agent(main agent)and a reducing agent(auxiliary agent).At a low temperature below 50℃,the main agent has a long half-life time for decomposing free oxygen radicals and cannot meet the breaking requirements.The reducing agent can activate it at low temperatures.The decomposition reaction of the oxidant solves the problem of low temperature gel breaking.The gel breaker will not produce SO^(2-)_(4)in aqueous solution,won’t cause calcium sulfate secondary precipitation,also won’t appear gel column.The special gel breaker is released slowly during the construction process to ensure the smooth fracturing operation.After fracture,the gel is completely broken.The particle size after gel breaking is the same as that of the normal guar gum gel fracturing liquid,70%is less than 109.6μm,95%is less than 195.2μm,the molecular weight of the polymer after gel breaking was 105,and the gel breaking effect is good.

关 键 词：氯化钙 加重聚合物压裂液 氧化还原型 破胶剂 破胶性能 

分 类 号：TE357.2[石油与天然气工程—油气田开发工程]