Tracking The Properties Of CO₂ Flooding Produced Liquid And Research Of Treatment Of Produced Sewage

With the industrial-scale applications of CO₂ flooding technology,the properties of CO₂flooding's produced liquid and produced sewege are different from water flooding's,which is because of CO₂'s unique physicochemical properties and oil recovery mechanism.Inorder to make oilfield waste water treatment technology adapt to CO₂ flooding's produced sewege,it is very significant to research the properties of CO₂ flooding's produced liquid and produced sewege,and propose a suitable produced sewege treatment method of CO₂ flooding for oilfield.Focused on CO₂ flooding and water flooding's production wells of Jilin oilfield's Block H59 and H79,tracking of the properties of produced liquid and produced sewege was carried out.The properties of CO₂ flooding's produced liquid were studied by tracking the produced liquid's water content,the components of the gas from the oil wells,the viscosity-temperature characteristics of produced oil,produced water's salinity and micromorphology of suspended solids.The influence of CO₂ on produced sewege's properties and the difference between CO₂flooding's produced sewege and water flooding's were studied by tracking the produced sewege's oil content,suspended solids content and the stability of the produced sewege.The most efficient flocculants mixture were selected by using bottle test method to screen different types of flocculants.Combined with Jilin oilfield's sewege treatment technical process,the suitable treatment technique for CO₂ flooding's produced sewege was proposed.The suspended solids of CO₂ flooding's produced sewege of Jilin oilfield's Block H59and H79 were distributed more unevenly and had smaller average particle size than water flooding's.The oil content and suspended solids content of CO₂ flooding's produced sewege were greater than water flooding's.And the stability of CO₂ flooding's produced sewege were stronger than water flooding's.In general,the treatment of CO₂ flooding's produced sewege was more difficult than water flooding's.With the progress of CO₂ flooding,the oil content and suspended solids content of CO₂ flooding's produced sewege increased,and CO₂flooding's produced sewege's stability getting stronger,the difficulty increased as well.The optimum flocculant mixture is 90mg/L PAFC+10mg/L non-ionic PAM.By applying this flocculant formula to oilfield technology,the treated produced water can be used as reinjection water.With the progress of CO₂ flooding,by increasing the flocculants concentration and treatment time appropriately can meet the demand of oilfield produced sewege treatment.