细菌对注聚驱采油污水中部分水解聚丙烯酰胺降解作用研究

针对大港油田长期聚合物驱后,采油污水中含有大量部分水解聚丙烯酰胺,增加了混合液的黏度和乳化性,使油水分离难度加大,采出水含油量严重超标,外排水对环境的污染也越来越明显,亟待解决部分水解聚丙烯酰胺的降解问题.文章对硫酸盐还原菌、腐生菌、芽孢杆菌和烃类降解菌在含部分水解聚丙烯酰胺污水中的繁殖情况,以及对部分水解聚丙烯酰胺的降解规律和最佳降解条件进行了研究,研究表明:将这些细菌接入部分水解聚丙烯酰胺溶液中,能较快地适应环境而快速生长,并对部分水解聚丙烯酰胺的降解具有较大的贡献,且腐生菌的贡献略大于硫酸盐还原菌,其次是芽孢杆菌和烃类降解菌;菌群对含部分水解聚丙烯酰胺污水进行处理,7d后部分水解聚丙烯酰胺质量浓度从52.31 mg/L降为2.78 mg/L,5 d后含油量从13.5 mg/L降为0 mg/L,使污水达到了外排标准.

STUDY ON THE DEGRADATION EFFECT OF BACTERIA ON PARTIALLY HYDROLYZED POLYACRYLAMIDE IN THE OIL RECOVERY SEWAGE BY POLYMER FLOODING

Aiming at lots of partially hydrolyzed polyacrylamide in the oil recovery sewage by adopting polymer flooding for a long time in Dagang oilfield, it could make the viscosity and the emulsibility of mixed solution increased. It's more difficult to separate oil and water,the oil content of produced water went beyond the standard greatly and it's more and more evident that the drainage foul polluted the environment. So it's urgent to solve the problem of degradation effect for partially hydrolyzed polyacrylamide. This paper researched the reproduction situation of sulfate reduction bacteria, saprophytic bacteria, bacillus and hydrocarbon degradation bacteria in partially hydrolyzed polyacrylamide of the oil recovery sewage, and the degradation law and optimal condition of degradation on partially hydrolyzed polyacrylamide have also been studied. Research results showed that those bacteria which were put into partially hydrolyzed polyacrylamide solution has become adaptable to the environment and grown up rapidly. They also have an important contribution on degradation for partially hydrolyzed polyacrylamide. And saprophytic bacteria had better effect to degradation of partially hydrolyzed polyacrylamide than that of sulfate reduction bacteria, next was bacillus and hydrocarbon degradation bacteria. The partially hydrolyzed polyacrylamide of the oil recovery sewage was treated by bacterial flora. The mass concentration of partially hydrolyzed polyacrylamide was decreased from 52.31milligram per liter to 2.78 milligram per liter after seven days, the oil content was decreased from 13.5 milligram per liter to zero after five days. Then the sewage has made up to the discharge standard.