低水化热水泥浆用微胶囊型热控材料制备及应用

Preparation and Application of Microcapsule Type Thermal Control Material for Low Hydrationheat Cement Slurry

基于天然气水合物低温、高压及电解质条件下的分解特性,以常规波特兰油井水泥为基料,外掺入微胶囊型热控材料(PCM-1),制备了一种低水化热水泥浆体系。采用自研半绝热测试实验设备对水泥浆体系早期水化过程中的温度进行了连续测量,以水泥浆体系最高温度(Tm)及最大水化温升(Tr)表征了PCM-1对水泥浆体系水化热的控制效应。结果表明,PCM-1的含量15%时(以水泥的质量为基准,下同),该水泥浆较纯水泥浆的水化最高温度下降了22.3℃,最大水化温升下降了23.6℃;24 h及48h水化热分别下降了7.68×10^4J及7.28×10^4J。微胶囊能够有效地控制水泥浆的水化温升及水化热,大幅降低了深水水合物层的固井风险。

Based on the decomposition characteristics of natural gas hydrate underlow temperature,high pressure and electrolyte conditions,a cement slurry system of low-hydration heat was developed with Portland oil well cement as base material and addition of micro-capsule type thermal control material(PCM-1).The temperature in the early hydration process of the cement slurry system was continuously measured by self-developed semi-adiabatic test equipment,and the control effect of PCM-1 on hydration heat was characterized by maximum temperature(Tm)and maximum hydration temperature rise(Tr)of the cement slurry system.The results showed that compared with that of pure slurry cement system,when addition amount of PCM-1 was 15%(taking the quality of cement as the benchmark,the same below),the hydration maximum temperature of the prepared cement slurry system decreased by 22.3℃and the maximum hydration temperature rise decreased by 23.6℃.In addition,24 h and 48 h hydration heat respectively decreased by 7.68′10^4 J and 7.28′10^4 J.Microcapsule can effectively control the hydration temperature rise and hydration heat of cement slurry,and greatly reduce the cementing risk of the hydrate layer in deep water.