中、低分子抗盐聚合物的评价研究

Evaluation of Salt-resistance Polymer with Medium-Low Molecular Weight

为解决低渗透薄、差油层聚合物溶液较难注入的问题,室内对中、低分子抗盐聚合物的理化性能、抗盐性、抗剪切性、稳定性以及流变性等性能进行了评价研究。结果表明,中、低分子抗盐聚合物具有相对分子质量低、增粘性好、抗剪切能力强、在污水条件下稳定性较好的特点。其中相对分子质量为700×104和1100×104的中、低分子抗盐聚合物在模拟污水体系条件下,其体系粘度可达到70mPa.s以上,表现出了较强的增粘性能;相对分子质量为300×104和500×104的低分子抗盐聚合物,在低相对分子质量条件下,表现出了较高的阻力系数和残余阻力系数。中、低分子抗盐聚合物能够解决油田污水利用的问题,并在污水体系中具有较好的稳定性;在模拟炮眼和地层的高速剪切条件下,其粘度保留率可以达到60%以上,具有较强的抗剪切性能。此外,中、低分子抗盐聚合物还表现出了良好的流变性、粘弹性以及驱油效果,具有良好的应用前景。

It is difficult to inject polymer solution into low permeability thin layers. In order to solve this problem, evaluation and research on physical and chemical properties, salt-resistance, shear-resistance, and rheologic property of salt-resistance polymer with medium-low molecular weight have been done in labs. The results show, the salt-resistance polymer with medium-low molecular weight can increase viscosity, high shear-resistance property and it is relatively stable in waste water. In simulated waste water system, the system viscosity of polymer with relative molecular weight of 700×104 and 1100×104 can be more than 70mPa.s, so, this system can increase viscosity effectively; The salt-resistance polymer with molecular weight of 300×104 and 500×104 present higher coefficient of resistance and residual coefficient of resistance. The salt-resistance polymer with medium-low molecular weight can be used in waste water with fair stability. Under the conditions of simulated penetration and high shear in formation, the reservation rate of its viscosity can be above 60%. The salt-resistance polymer with medium-low molecular weight also has good rheology, viscoelasticity and oil sweeping efficiency, so, it will be used more widely in future.