Research Of Influence Factors And Keeping Technology On HPAM Solution Viscosity In Foam Flooding In Chengdong Oilfield

Foam flooding pilot test in Chengdong Oilfield is Sinopec major pilot testproject.Ploymer solution prepared by oil sewage resulted in significant viscosityreduction(down to1-5mPa·s),influencing the application efficiency.So the technology ofeffction on viscosity of polymer solution is carried out. Factors affecting HPAM viscosityare tested in this paper,such as water quality,corrosion,chemical activities and so on.Thispaper identifies sulphide as the master factor affecting HPAM viscosity too.Results showthat SRB transformed sulfur element of foam agent into sulphide.According to the characteristics of the sewage, this paper completed a variety of thecomparative study. this paper puts forward the biological oxidation that removes sulphideand SRB competitive inhibition biochemical technology. In laboratory simulation test, useof bacteria (SOB) oxidation in wastewater removes sulphide, polymer solution viscositywith the removal sewage preparation is40mPa·s, viscosity retention rate above80%.Based this, use of denitrifying bacteria (DNB) inhibitt SRB (sulfate-reducing bacteria)activity in the sewage, removed sewage preparation of polymer solution can be simulatedreservoir conditions for30days can still keep viscosity in34mPa·s above.Established the treatment scale for1200m3/d biochemical process, after sewagewater quality indexes were superior to standard, The viscosity of HPAM solution is up to35mPa·s. the whole process is smooth operation, water quality index is stable in the pilot amonth time. Preparation of polymer solution viscosity can still reach26mPa·s with thetechnology of sewage treatment alternative water, it fully meet the field productionrequirements (now the production requirements is polymer solution viscosity20mPa·sabove).This paper research and test formed a production sewage treatment integratedtechnology.The results can be used to guarantee the quality and effct of field HPAMinjection. In summary, the results of this reseach have positive guiding significance forresourceful disposal of oil field waste water.