Quantitative Turbidimetric Determination of Novel Water Soluble Polymers for EOR

The factors influencing quantitative determination of 3 classes of EOR polymers by turbidimetry were investigated.6 salt tolerant polymers(STPs),1 hydrophobically associating polymer(HAP),and 2 HPAM polymers were taken in the study.In determining an STP sample of concentration 100—800 mg/L,the turbidity measured in NTU was fairly steady in 13—17 min of reaction of glacial acetic acid,sodium hypochlorite,and polymer and,howerver,good linear relationships between polymer concentration and turbidity with R20.999 were observed for any reaction time in range 3—20 min and led to polymer concentration determinations with relative error5%.For 1 HPAM sample sheared in 0—120 min and 4 STP samples,an enlarged difference in turbidity measurements was observed with increasing difference in molar mass under conditions of similar hydrolysis degree and equal polymer concentration.For an STP sample of polymer concentration 100—600 mg/L,a higher turbidity measurement was obtained at a lower hydrolysis degree.It was concluded that this turbidimetric method can be used for determining polymer concentration of flooding solutions of all these classes of EOR polymers at polymer injection stations with measurable polymer concentration in range 100—900 mg/L and with reaction time of 3 min.Polymer concentration-turbidity(in NTU)standard working curves were constructed for an HAP,an STP,and an HPAM polymers with value R2 of fitted linear equations being of 0.9995,0.9989,and 0.9995 and relative error of polymer concentration determinations being of 1.24%,2.23%,and 1.82%,respectively.