Research And Application Of Medium And High Temperature Retarder For Oil Well Cement

Retarder for oil well cement is one of the most significant additive agents,which is also widely applied in this area.With the deepening of exploration and development,deep wells and ultra-deep wells emerge in endlessly.There is more and more demand for oil retarder cement retardants,especially high-temperature retarder.Thus research and development of high-temperature retarder cement additives become a main direction in recent 10 years.The temperature and scope of high-temperature retarder is also rising.This paper analyzes different medium-and high-temperature retarder system at home and abroad.A copolymer retarder for medium and high-temperature oil wells was developed for 60-150 ?C(bottom hole cycle temperature).Copolymer retarder(AMPS/AA/SSS/IA)was synthesized through using AMPS,acrylic acid(AA),sodium styrenesulfonate(SSS)and itaconic acid(IA).The structure was characterized by FTIR and 1HNMR,which confirmed that the synthesized copolymer was the target product.The optimum synthetic conditions of the copolymer retarder were pH 6,initiator 2.5%,polymerization time 5 h and polymerization temperature 60°C.The high-temperature retarder was analyzed and evaluated the effects of retarding agent on the compressive strength of cement paste,the relationship between retarder dosage and the thickening time of cement slurry,and compatibility.Results showed that the amount of self-synthesized medium and high temperature retarder had a good linear relationship with the thickening time of cement slurry.The compatibility of the water agent was good,the intensity of the cement stone decay was small,the amount of sensitivity and temperature sensitivity can be controlled within 20%,indicating that the high-temperature retarder is a comprehensive performance of the oil well cement retarder.The retarder can be used in the conventional density cement slurry system,the high density cement slurry system,the high density high strength cement slurry system,the conventional low density cement slurry system,the high strength low density cement slurry system,the low density anti channeling cement slurry system,and so on.This cement slurry system is compatible with other additives.The high-temperature retarder has been used in two wells of cementing company Xinglongtai site.The on-site construction is normal,and the cementing quality is qualified.