低聚季铵盐与破乳剂复配提高聚驱采出液水质的研究

Improvement of the quality of the produced water containing polymer by compounding of demulsifier with oligomeric quaternary ammonium salt

针对南阳油田聚驱采出液脱水困难、水质浑黄等问题,采用低聚季铵盐和破乳剂复配提高聚驱采出液的水质.通过对南阳油田聚驱采出液脱水率、脱出水含油量的测定,结合脱出水界面情况,采用破乳剂单剂初步筛选和两组分复配优化的方法,从18种破乳剂单剂及3种低聚季铵盐中筛选出协同破乳效果和脱出水质最佳的配方.实验结果表明:在温度55℃,破乳剂AE-932质量浓度为15 mg/L,低聚季铵盐MD-50质量浓度为25 mg/L时,60 min脱水率达98%,脱出水含油量小于50 mg/L,且脱水速度快,脱出水清,油水界面齐.表明低聚季铵盐MD-50对协同提高破乳剂的脱水效果具有显著作用.

The produced liquid containing polymer in Nanyang Oilfield is yellowing and turbid,and it is difficultly dehydrated.For this reason,the quality of the produced water is improved by compounding of demulsifier with oligomeric quaternary ammonium salt. Through the determination of the dehydration rate,the oil content and the interface state of the dehydrated water from Nanyang oilfield polymer flooding produced liquid,single demulsifiers are screened preliminarily,and then two-component compound demulsifiers of demulsifier with oligomeric quaternary ammonium salt are optimized.Finally,the optimal formula with the best collaborative demulsification effect is selected from 18 single demulsifiers and 3 oligomeric quaternary ammonium salts.The experimental results show that at 55℃,when the demulsifier AE-932 is 15 mg/L and oligomeric quaternary ammonium salt MD-50 is 25 mg/L,the dehydration rate of the produced water can reach to 98%in 60 min,the oil content in the dehydrated water is less than 50 mg/L.The dehydration method is of high dehydration speed,high quality of dehydrated water and clear oil/water interface.It is shown that oligomerization quaternary ammonium salt MD-50 can collaboratively improve the dehydration effect of demulsifier.