二氧化碳腐蚀对油井水泥石抗压强度的影响(英文)  

EFFECT OF CARBON DIOXIDE CORROSION ON COMPRESSIVE STRENGTH OF OILWELL CEMENT

作　　者：张景富[1] 王宇[1] 徐明[2] 赵强[3] 

机构地区：[1]大庆石油学院,提高油气采收率教育部重点实验室,黑龙江大庆163318 [2]西南石油大学石油工程学院,成都610500 [3]冀东油田公司,河北唐山063200

出　　处：《硅酸盐学报》2009年第4期642-647,共6页Journal of The Chinese Ceramic Society

摘　　要：利用扫描电子显微镜、强度测试仪检测了不同条件下二氧化碳腐蚀油井水泥的产物、微观结构及抗压强度,研究了二氧化碳腐蚀油井水泥的机理及腐蚀对水泥强度的影响,分析和评价出了适合于大庆油田不同温度深井条件的水泥浆体系。结果表明:二氧化碳对油井水泥的腐蚀作用本质在于二氧化碳能够与水泥的水化产物发生化学作用,生成了各种不同晶体结构的CaCO3产物,使原有的水泥石微观结构遭到破坏,导致腐蚀后水泥石的强度下降;温度和二氧化碳分压增高;改善水泥石抗腐蚀能力应以有效改善水泥水化产物及微观结构为基础,添加抗腐蚀填充材料能有效改善水泥浆体系的抗腐蚀能力。The composition of the corrosion products, the microstructures and the compressive strength of corroded cement samples were examined by scanning electron microscopy and strength testing under different corrosion conditions by carbon dioxide （CO2）. The corrosion mechanism of oilwell cement by CO2 and the effects of CO2 corrosion on the compressive strength of oilwell cement were investigated. Oilwell cement slurries suitable for the deep wells at different temperatures in the Daqing oil field were analyzed. The results show that the cement corrosion by CO2 occurs by the destruction of the microstructure formed by the original hydration products of oilwell cement. This destruction is affected by CaCO3, with different crystal structrue, which is produced by the chemical reaction between CO2 and the original hydration products. For the cement corrosion by CO2, the compressive strength decreased with increaseing the curing temperature and the CO2 differential pressure. The development of anti-corrosive cement systems should be based on the effective improvement of the hydration products and the microstructure of cement stone. A corrosion resisting additive named DCR used can effectively improve the corrosion resistance of the system.

关 键 词：油井水泥 二氧化碳 腐蚀 抗压强度 

分 类 号：TE256[石油与天然气工程—油气井工程] TE980.1