市政污水回注储层处理技术研究

Research on reservoir treatment technology of municipal sewage reinjection

回注水水量是油田注水开发重要的影响因素,在注采不平衡、采出水量低于注入水水量时,确立注入水补充水源具有重要意义。以处理后市政污水与延长油田不同层位采出水为研究对象,通过水质分析及配伍性研究,探究处理后市政污水作为注入水补充水的可行性。结果表明,长2、长6及长7层位采出水与市政污水以8∶2的体积比混合后,在复合阻垢剂H-1加量为80 mg/L、除氧剂加量为60 mg/L、PAC与PAM加量分别为100 mg/L、1 mg/L时,处理后混合水样腐蚀速率降低至0.076 mm/a以下,结垢量由处理前的156、229、378 mg/L分别降至17、26、24 mg/L,且处理后混合水样对岩心伤害率低于20%,处理后市政污水可以成为油田注入水的补充水。

The amount of reinjection water is an important factor affecting the oilfield waterflooding development.When the injection and production are unbalanced and the produced water is lower than the injected water,it is of great significance to establish the water source of injection water.Taking the treated municipal sewage and the produced water in different layers of Yanchang oilfield as the research object,the feasibility of treating municipal sewage as injection water to supplement water was explored through water quality analysis and compatibility study.The results show that,when the produced water in Chang 2,Chang 6 and Chang 7 layers is mixed with municipal sewage at a volume ratio of 8∶2,the corrosion rate of treated water decreases below 0.076 mm/a when the dosage of compound scale inhibitor H-1 is 80 mg/L,the dosage of deaerator is 60 mg/L,and the dosage of PAC and PAM are 100 mg/L and 1 mg/L respectively.The amount of scaling decreased from 156,229 and 378 mg/L to 17,26 and 24 mg/L,respectively,and the damage rate of treated mixed water to core was less than 20%.After treatment,municipal sewage could be used as supplementary water for oilfield injected water.