摘要
热采井、稠油井固井水泥浆一般使用加砂水泥浆,且一般是在110～250℃下研究其水泥石抗压强度。室内研究结果表明,110和250℃为原浆水泥石强度衰退的2个临界温度点,温度越高,强度衰退幅度越大,且衰退速度越快,超过300℃后,养护3 d的水泥石强度低至3 MPa。通过在280～320℃下研究抗压强度的变化情况,对水泥浆外加剂和外加材料特别是硅砂粒径和掺量进行了优选,开发出了满足稠油井固井施工综合性能的水泥浆,该水泥浆选用D_(80)为0.090 mm的硅砂,其适宜加量为47%,选用(6%～8%)微硅和(0.7%～0.8%)珍珠岩作悬浮稳定剂,选用了降失水剂LT-2、分散剂SXY和早强剂CK21,其在350℃、21 MPa下养护72 h的水泥石强度不低于14 MPa,且无渗透现象。表明该水泥浆在320℃高温蒸汽冲击力下能保持高强度,对开发蒸汽吞吐稠油井具有极其重要的意义。
In thermal production well and heavy oil well cementing,cement slurry is often formulated with sand-content slurry,and the compressive strength is generally tested qt 110～250℃.Laboratory study showed that 110℃and 250℃are the critical temperatures at which the compressive strength of set cement of the pure cement slurry begins to decline.It was also found that the higher the temperature,the greater the amplitude of declination and the faster the declination.At temperatures above 300℃,the compressive strength of a set cement aged for 3 hours is reduced to 3 MPa.A laboratory study was done on the change of the compressive strength of set cement in 280～320℃,optimizing the particle size and concentration of cement slurry additives such as the blended sand.A cement slurry was formulated based on the study.In the sand added,80%had particle size of 0.090 mm,and the optimum concentration was 47%. Other additives,such as fine silica(suspension stabilizer)(6%～8%),perlite(suspension stabilizer)(0.7%～0.8%),LT-2(filtration reducer),SXY(dispersant) and CK21(early strength additive),were added to improve the slurry properties.The set cement aged at 350℃,21 MPa for 72 hours had a compressive strength of 14 MPa,and was impermeable.This means that the set cement can retain its compressive strength against the hot vapor impact at 320℃.
出处
《钻井液与完井液》
CAS
2009年第5期50-54,共5页
Drilling Fluid & Completion Fluid
关键词
固井
热采井
稠油井
抗高温水泥浆
硅砂
强度衰退
Cementing
Thermal production well
Heavy oil well
High temperature cement slurry
Silica sand
Strength declination
作者简介
第一作者简介：罗畅，1984年生，在读硕士研究生，研究方向为油井水泥外加剂的研究及固井水泥浆的设计。地址：成都市新都区西南石油大学硕士07级5班；邮政编码610500；电话15982375977；E-mail：luoyang_swpu@163．COM。
