Research On The Mechanism Of Oxidating Viscosity-reducing And Ploymer Degradation For ASP Produced Water Of Oilfield

Ingredients of ternary ASP oilfield produced water quality are very complex.Reinjection process is very difficult and its viscosity is difficult to meet the standards.This causes formation plugging and reduces oil recovery.So analyze ternary water viscosity and its influence,improve injection water effect has been widespread concern.We study on reducing the viscosity of ASP water by oxidation,compare Fenton,ferrate,NaClO on the effects of HPAM and viscosity of ternary produced water.Discuss the role of the water reaction time,pH,temperature viscosity factors affecting on NaClO oxidation produced water.Emphasis on the effect of pre-aeration process to NaCl O oxidation,the HPAM degradation process and mechanism were analyzed and discussed.The experiments show ternary ASP oilfield produced water is high oil content,high HPAM content,high surfactant content and high viscosity values.The viscosity values is 6⁸m Pa·s,oil content is 150⁶84 mg/L,some oil region reached 1400 mg/L,HPAM content is606¹183 mg/L,other indicators are also relatively high,such as SO₄^2-,pH and so on.Fenton treatment of produced water viscosity decreased 79%,HPAM lower rate of74.6%,oil decreased 96%,Ferrate peroxide solution viscosity less than 50%,NaClO solution oxided viscosity of the ternary produced water fell to 52%,HPAM lower rate of 65.2%.NaClO response factors were as follows:NaClO dosage,pH,initial viscosity values of ternary produced water,NaClO dosing method,60 min to meet the needs of continuous reaction.NaClO oxidation produced water viscosity ratio decreases as the pH rises,raising the temperature,the viscosity value becomes small downward,Little effect on the concentration of the HPAM in ternary water.After the pre-aeration,NaClO oxidation produced water of Xingshi viscosity reduction of about 68.7%,Beishisan produced water viscosity reduction of about 75.4%,Xingshi HPAM produced water decline was 70%,Beishisan produced water decline was 59.8%.Produced water viscosity threshold is 2.1mPa·s,After HPAM molecular weight degradation can significantly reduce the viscosity of the solution.The degradation methods include oxidation and chain scission to change molecular.UV spectrophotometer full band scan to determine acrylamide HPLC detection wavelength was 210nm.Using HPLC and the degradation of the material by standard HPLC chromatograms,we think after the process of HPAM chain scission degradation,the macromolecular polymer into smaller molecular weight polymer,the small molecules oxidized acrylamide polymer,then oxide into small inorganic molecules.