摘要
深水浅层疏松砂岩地层孔隙度大,温度较低,通常面临水泥浆抗压强度差、发展缓慢、第二界面胶结质量差等问题,给固井施工带来了严峻的挑战。且现在很多外加剂价格昂贵,性能相差很大。结合深水疏松砂岩地质特点,调研多种市场上常用的外加剂,进行对比实验,优选出具有高性价比的早强剂ACL,分散剂CF42L,降失水剂CG81L,缓凝剂RE-L,增强剂ESC-S等外加剂,形成一套适应于深水浅层疏松砂岩地层低密度水泥浆体系,实现对常规低密度水泥浆体系的降本增效。该水泥浆体系密度范围在1.4~1.7g/cm^(3),满足沉降稳定性要求,流动性好,24h抗压强度大于12MPa,48h抗压强度大于14MPa,满足深水浅层疏松砂岩地层固井要求。
The shallow unconsolidated sandstone formation in deep water has high porosity and low temperature, and it is often up against the problems including the poor compressive strength of cement slurry, slow development and poor cementation quality at the second interface, etc., which pose serious challenges to the cementing operation. In addition, many admixtures are expensive, and the performances are very different. Based on the geological characteristics of unconsolidated sandstone formation in deep water, a variety of commonly used admixtures in the market is investigated,and the comparative experiments are carried out, and some admixtures with high performance-price ratio are optimized including early strength agent ACL, dispersant CF42 L, fluid loss additive CG81 L, retarder RE-L and enhancer ESC-S;finally a low-density cement slurry system is established which is adapted to the shallow unconsolidated sandstone formation in deep water with a lower cost and higher efficiency. This new cement slurry system has a density ranging from 1.4 g/cm^(3) to 1.7 g/cm^(3) with a satisfaction of the sedimentation stability requirement and good mobility, and its 24-hour and 48-hour compressive strength is greater than 12 MPa and 14 MPa respectively which can meet the cementing requirements of shallow unconsolidated sandstone formation in deep water.
作者
刘兆年
岳家平
王杰
孙挺
武治强
LIU Zhao-nian;YUE Jia-ping;WANG Jie;SUN Ting;WU Zhi-qiangu(State Key Laboratory of Offshore Oil Exploitation.Beijing 100028,China;CNOOC Research Institute,Beijing 100028,China;China l/niversity of Petroleum-Beijing,Beijing 102249,China)
出处
《化学与粘合》
CAS
2021年第1期12-16,共5页
Chemistry and Adhesion
基金
海洋石油高效开发国家重点实验室第四批开放基金课题。
关键词
深水
疏松砂岩
外加剂
低密度水泥浆
Deep water
unconsolidated sandstone
admixture
low-density cement slurry
