三元配注系统各节点含氧量及二次曝氧作用分析

Analysis of Oxygen Content at Each Node of Ternary Injection System and the Secondary Oxygen Aeration Effect

油田化学驱三元配注系统多采用“污配污稀”运行模式,三元系统污水均为深度水经曝氧处理后使用,污水成分复杂,含有大量微生物,对聚合物黏度造成严重影响。同时,污水中的还原性离子在配制时易发生氧化还原反应,也会大幅降低溶液黏度。将污水曝氧处理,可减少聚合物溶液的生物降解,也可减少聚合物分子的氧化降解。因此通过开展模拟压气曝氧以及高压曝氧现场试验,分析降低黏损的效果。试验证明,二次曝氧对厌氧菌的繁殖有抑制作用,二次曝氧污水配制母液在低压端不能起到降低黏损的作用,但在高压端有一定降低黏损的效果。

The ternary injection system of chemical flooding in oilfield usually adopts the running mode of“Wastewater preparation and wastewater dilution”.The wastewater in ternary injection system is deep water used after oxygen aeration treatment,contains a lot of microorganisms,and its composition is complicated,which has influence on the polymer viscosity.Meanwhile,reducing ions in wastewater are prone to redox during preparation,which can greatly reduce the viscosity of the solution.Oxygen aeration treatment of wastewater can reduce the biodegradation of polymer solutions,the oxidation degradation of polymer molecules can be reduced as well.Therefore,it is analyzed whether the viscosity loss can be effectively reduced by carrying out the field test of simulated pressured oxygen aeration and high-pressure oxygen aeration.Results show that the secondary oxygen aeration can inhibit the reproduction of anaerobic bacteria,and the mother liquor prepared by the secondary oxygen aeration wastewater cannot reduce the viscosity loss at low pressure side,but can reduce the viscosity loss at high pressure side to some extent.