一种碳纤维分散液的制备及其在固井水泥浆中的应用

碳纤维是一种高性能纤维,能有效改善水泥石的力学性能。为了克服碳纤维在使用过程中不易分散的缺点,对碳纤维分散剂种类、分散剂加量及碳纤维加量进行优选,制备出一种碳纤维分散液,并对该碳纤维分散液在固井水泥浆中的应用效果进行评价,最后对加入碳纤维分散液的水泥石微观形貌进行观察。结果表明：碳纤维分散剂CDA-2能改善碳纤维在水溶液中的分散效果,当加量为0.6%时,形成的碳纤维分散液较稳定；当碳纤维分散液中碳纤维的加量为4%,此时形成的碳纤维分散液稳定性最好且碳纤维加量最优。使用碳纤维分散液配制的固井水泥浆体系与将碳纤维直接加入的固井水泥浆中相比,水泥浆体系常规性能相差不大,但力学性能明显提高,养护3 d后碳纤维分散液水泥石的抗压强度、抗冲击强度、抗折强度比直接加碳纤维水泥石分别提高6.8%、7.6%、10.1%。碳纤维分散液能使碳纤维更好的分散在水泥石中,形成网状结构,通过桥联阻裂、拔出耗能作用增强增韧水泥石。

Preparation of Carbon Fiber Dispersion Liquid and Its Application in Cement Slurry

Carbon fiber is a high-performance fiber that can effectively improve the mechanical properties of cement stone. In order to overcome the shortcomings of carbon fiber being difficult to disperse for using, the carbon fiber dispersant type, dispersant amount and carbon fiber amount were preferably selected to prepare carbon fiber dispersion liquid, and the application effect of the carbon fiber dispersion liquid in cement slurry was evaluated. Finally, the microstructure of cement stone added with carbon fiber dispersion liquid was observed.The results show that the carbon fiber dispersant CDA-2 can improve the dispersion effect of carbon fiber in aqueous solution. When the addition amount is 0.6%, the carbon fiber dispersion formed is stable; when the carbon fiber dispersion is 4%, the formed carbon fiber dispersion has the best stability and the optimum amount of carbon fiber. Compared with cement slurry prepared by directly adding carbon fiber, the cement slurry system prepared by using the carbon fiber dispersion liquid has little difference in conventional performance, but the mechanical properties are obviously improved. After curing for 3 days , the compressive strength, impact strength and flexural strength increased by 6.8%, 7.6%, and 10.1%, respectively. The carbon fiber dispersion liquid can better disperse the carbon fiber in the cement stone to form a network structure, and improve the toughness and strength by bridging the cracking and pulling out the energy consumption.