煤层气泡沫固井新型早强剂FC-A及其性能

Performance of a New Accelerator FC-A for Foam Cement Slurry of Coal Bed Methane

针对煤储层温度低,固井时水泥水化反应速率慢,水泥浆稠化时间长,水泥石抗压强度发展缓慢等问题,依据水泥浆的水化机理,以不同离子对硅酸钙矿物熟料水化速率的影响规律为理论基础,研制出过渡金属复合盐类新型低温早强剂FCA,并系统评价了该早强剂不同加量(1%、2%和3%)情况下的水泥浆性能,与早强剂氯化钙(Ca Cl2)进行对比,得到了FC-A对水泥浆的影响规律:早强剂FC-A能够提高水泥石低温早期抗压强度,完全满足6 h抗压强度(39℃、常压)大于等于4.0MPa技术指标;早强剂FC-A能够缩短水泥浆稠化时间,加有FC-A早强剂的水泥浆稠化时间与水泥原浆稠化时间之比(32℃、8.3 MPa)为0.438;FC-A对水泥浆的流变参数和初始稠度基本无影响,具有优异的低温早强和促凝作用,是一种综合性能优异的新型早强剂。

To solve such problems like low temperature of coal bed methane formation,low rate of hydration reaction,long time of cement slurry thickening time and low rate of cement stone compressive strength,a new transition metal salts accelerator FC-A according to hydration mechanism was introduced and the effect of different ions on hydration rate of calcium silicate mineral,and the performance of cement slurry with different FC-A doses（ 1%,2%,3%） is evaluated systematically. Compared with Ca Cl_2,it is concluded that the accelerator FC-A can improve the initial compression strength of cement stone,satisfying the request of 6 h compression strength of final cement stone（ 39 ℃,normal pressure） ≥4. 0 MPa; FC-A can shorten the cement thickening time,the ratio of thickening time between cement slurry which is added FC-A and original cement slurry is 0. 438（ 32 ℃ 、8. 3 MPa）; FC-A has no effect on the rheology and initial consistency of cement slurry,proven to be a new accelerator superior to Ca Cl_2.