Preparation And Performance Evaluation Of Cementing Latex Cement

With the exploitation of oil and gas resources gradually into the late, its mining was more and more difficult, especially the development of high temperature and high pressure wells and unconventional oil and gas reservoirs. The demend for cementing techniques had become more sophisticated, cement slurry not only had good mechanical properties, but also had excellent engineering properties. Cement sheath must maintain good zonal isolation to avoid channeling between oil, gas and water layers during the entire life cycle of the well.In response to these problems, the mechanical properties and conventional slurry properties of SBR, TJR and HNJR anionic latex cement slurry were studied in order to solve the problem in this topic.Stability study results of latex cement slurry showed that, SBR cement slurry didn’t need extra stabilizer; AES could be used as TJR cement slurry stabilizer; AES and6501/OA complex system could be used at room temperature for HNJR slurry stabilizer,6501/OA/AES could be used as high-temperature slurry stabilizer.Latex cement slurry defoamers screening results show that, the effect of silicon ester defoamer was better than ether esters defoamer, especially the polyether-modified silicone defoamer DZ-1400X. The anti-foaming effect could be significantly increased by mixing use of DZ-1400X and tributyl phosphate at a certain percentage. Through the research of latex’s impact on the slurry static fluidity, the mechanical properties and thickening performance, and combined with economic considerations,5%latex adding amount was better and2%stabilizer adding amount was more appropriate.Latex cement mechanical properties results showed that, compared with the puree cement, SBR cement compressive strength could be increased by45.8%, the flexural strength could be increased by42.3%; TJR cement compressive strength could be increased by44.9%, the flexural strength could be increased by77.1%; HNJR cement compressive strength can be increased by28.9%, the flexural strength could be increased by39.6%. Under the same conditions, the curing time on the impact of cement strength was better than the curing temperature.Conventional latex slurry performance study showed that, the latex cement slurry system had normal density, the free fluid was almost zero; Coordinated with fluid loss agent, the slurry’s fluid lose was less than50mL; latex slurry also had good rheological properties; SBR cement slurry and HNJR cement slurry had excellent stability of settlement at high temperature; SBR cement slurry and HNJR cement slurry had normal thickening linear with approximate right angle thickening, the transition time was short and the initial consistency was low; the latex cement slurry’s SPN value showed excellent anti-channeling effect.The initial evaluation about the self-healing properties of latex slurry showed that, SBR showed poor absorption of oil and gas properties, TJR and HNJR were better; HNJR swelled rapidly in kerosene, forming a viscous system with a bit of mobility. The results showed HNJR cement slurry had the feasibility to achieve self-healing through indirect analysis.