Study On Synthesis And Properties Of Temperature-resistanc And Salt-resistance Copolymer For EOR

In the field application of ASP flooding, partially hydrolyzed polyacrylamide (HPAM)under the condition of high temperature and high salinity exposed the shortcomings which areviscosity reducing violently, degradation, hydrolysis obviously and affected the oil recoveryseriously.This article synthetizes the sulphonated polyacrylamide (SPAM) by using binary monomerand ternary monomer to overcome the shortcomings of the HPAM. This article also study thecopolymer structure characterization and performance evaluation in aqueous solution. Theexperimental results show that:(1) Binary polymerization. The sulfonated polyacrylamide ofacrylamide (AM) and2-acrylamide-2-methyl propane sulfonic acid (AMPS) was carried outby using a complex initiation system which contains the redox initiator (ammonium persulfateand formaldehyde sulfoxylate sodium sulfite) and water-soluble azo initiator. In the reactionsystem, Adding chemical additives(urea, ethylene diamine tetraaccetic acid,N,N-Dimethylethylenediamine) get the optimum process conditions(reaction system for100ml) is pH of7, reaction temperature of10℃, monomer ratio of8:2, monomerconcentration of30%, the ratio of redox and azo of1:3, EDTA is0.8ml, urea of0.06%,N,N-Dimethylethylenediamine of15μL, get the molecular weight of AM/AMPS up to1.05x107.(2) Ternary polymerization. On the basis of binary copolymerization introduce the thirdmonomer sodium p-styrene sulfonate (SSS), synthesized the ternary sulphonatedpolyacrylamide AM/AMPS/SSS. The results of the single factor investigation and theorthogonal experiment show that the optimum process conditions is reaction time of8h,monomer ratio of8:2, the content of the third monomer of0.3g, monomer concentration of20%, the ratio of redox and azo of1:4, reaction temperature of10℃, pH of9, redoxconcentration of0.04%. Process parameters are powdered solid product the best dryingtemperature of45℃, drying time of19h, copolymer particles soaked by anhydrous ethanolget high apparent viscosity. Investigate the content of sodium p-styrene sulfonate, styrene,acrylic acid (AA) influence on the apparent viscosity of the copolymer. It is found that thesynthesis of the terpolymer viscosity order is: SSS> AA> styrene.(3) Performance evolutionof the binary/ternary SPAM and HPAM. The performance in aqueous solution showed that theternary copolymer apparent viscosity is low, but its heat resistance, salt resistance, solubility,reinforced viscosity effect, thermal stability, shearing resistance are better than the binarypolymer and HPAM. The ternary copolymer in90℃, salinity is20000mg/L under thecondition of30days, The viscosity changed from12.6mPa.s to8.2mPa.s.The viscosityretentionrate is65.1%.