稀释聚合物用含聚采出水曝氧处理工艺优化现场试验

Field Tests on Optimization of Aeration Treatment Process for Polymer-containing Produced Water used for Diluting Polymers

目前油田含聚采出水中还原性物质二价铁和硫化物含量高,对聚合物分子产生严重的降解作用,造成稀释聚合物母液时聚合物溶液初始黏度下降,影响聚驱配注效果。为有效降低含聚采出水中还原性物质含量,可采用曝氧技术处理含聚采出水。曝氧工艺分两种,空压机曝氧工艺和射流器曝氧工艺,但曝氧效率低,还原性物质去除效果差;将空压机曝氧工艺改进为曝气头曝氧工艺,可提高曝氧效率;通过对空压机曝氧工艺、射流器曝氧工艺、曝气头曝氧工艺进行现场试验,对处理效果进行对比。最终结果表明,陶瓷刚玉曝气头能提高氧的利用率,陶瓷刚玉曝气头曝氧工艺比现有曝氧工艺曝氧效果更佳,在气水比0.6∶1~1.5∶1,曝氧时间3~6 h条件下,可有效降低含聚采出水中的还原性物质含量,提高稀释聚合物母液黏度。

At present,polymer-containing produced water in oilfields mostly contains reducing substances(divalent iron and sulfide),which have serious degradation effect on polymer molecules,resulting in the decrease of initial viscosity of polymer solution when diluting the mother solution of polymer,affecting the polymer flooding injection effect.In order to effectively reduce the reducing substances in produced water containing polymer,oxygen aeration technology can be used to treat produced water containing polymer.There are two existing oxygen aeration processes,air compressor oxygen aeration process and jet aeration process,but the oxygen aeration efficiency is low,and reducing material removal effect is poor.The aeration process of air compressor is improved to aeration process of aerator head to improve aeration efficiency.The field tests of air compressor aeration process,jet aeration process,and aerator head aeration process are carried out,and the treatment effects are compared.The results show that the ceramic corundum aerator head can improve the utilization rate of oxygen.The aeration effect of the ceramic corundum aerator head is better than the existing aeration process.Under the conditions of gas-water ratio 0.6∶ 1 ~ 1.5∶ 1 and aeration time 3 ~ 6 h,the reducing substances in produced water containing polymer can be effectively reduced,and the viscosity of diluted polymer mother liquor can be improved.