石油钻采工艺2023，Vol.45Issue(4)：432-440,454,10.DOI:10.13639/j.odpt.202210023
高酸性气体对硫铝酸盐水泥石腐蚀作用机理
Corrosion mechanisms of sulfoaluminate cement by highly sour gas
摘要
Abstract
This research investigated the property variation and corrosion mechanisms of sulfoaluminate cement in highly sour services.The variations of the specific area and pore structure of the cement after corrosion were measured by cryogenic nitrogen adsorption tests(the BET and BJH methods).The changes in hydration products after corrosion were tested using the X-ray diffractometer(XRD)and thermal analyser(TG/DTG).Finally,the micro-scale morphological variations of hydration products of cement after corrosion were observed using the scanning electron microscope(SEM).The results showed that SAC presents a desirable strength at 60℃.The hydration products are mainly Aft after 14-day corrosion at 60℃and CaSO 4·2H2O after 14-day corrosion at 90℃.Notable stratification of the set cement is observed after corrosion by H2S.The outer layer is first corroded,while the inner layer presents short-term strength growth due to swelling.The mechanism of H2S corrosion is that C-S-H and CH in the hydration products of cement react with H2S respectively and produce swelling Aft and CaSO4·2H2O,which results in cracking of cement and reduction in compressive strengths.The findings of this research provide the experimental and theoretical basis for applications of sulfoaluminate cement in cementing of oil and gas wells with highly sour gas.关键词
高含硫气井/硫铝酸盐水泥/抗压强度/腐蚀机理/固井Key words
highly sour gas well/sulfoaluminate cement/compressive strength/corrosion mechanism/cementing分类
能源科技引用本文复制引用
张磊,武广瑷,武治强,幸雪松,蔡靖轩,程小伟..高酸性气体对硫铝酸盐水泥石腐蚀作用机理[J].石油钻采工艺,2023,45(4):432-440,454,10.基金项目
中海油科研项目"文昌9-7油田开发钻完井基本设计"(编号:2022BD-11-2). （编号:2022BD-11-2）
