Study On The Scale Mechanism Together With The Synthesis And Evaluation Of Scale Inhibitor In The ASP Flooding

ASP flooding recovery is an important technical of tertiary oil recovery,ASP flooding recovery is more and more widely applied in recent years.With the wide used of ASP flooding,the recovery efficiency is improved,but,because of the differences between chemical flooding and water flooding,many technical problems are triggered.The different degree scaling phenomenon happened in near wellbore area of reservoir and produced liquid,reservoir or pipe plug,So as to induce the production safety hidden trouble,shorten operation cycle,increase the cost of production and a series of problems.Scaling becomes the strong alkali asp flooding technology popularization resistance.This paper takes actual situation in fourth factory of Daqing oilfield as the research object,combined with geological,chemical,oilfield development,such as discipline theory basis,through developing the core components,produced liquid sample water quality and the scale of a large number of analysis,and by using indoor simulation experiment has been clear about the alkali asp flooding system into a scaling mechanism: After alkali injection formation,rock mineral dissolution in under the action of strong base,forming a large number of Ca2+,Mg2+ and Si4+ plasma,formation water solution the original ion balance,that alters the geological conditions of oil displacement system migration,Ca2+,Mg2+ ion crystal precipitation,Si4+ ion adsorption in crystal surface to form a new calcium magnesium silicate scale,at first the floc suspended in solution,the final gather into scale.Anti-scaling agent mechanism including chelation,crystal distortion,and the roles of electric double layer,the electrostatic repulsion and threshold effect,etc..By the nature of the ternary copolymerization monomer antiscale agent,optimize radical polymerization reaction as the synthesis reaction principle for this experiment.Combined with the feature of strong alkali asp flooding system development,anti-scaling agent synthesis process requirements and application promotion trend and so on factors,optimization by repeated experiments,determined the suitable for alkali asp flooding system of anti-scaling agent formula and synthesis conditions: Terpolymer polymer scale inhibitor was self developed.Malefic anhydride(MA),acrylic acid(AA),2-acrylamide base-2 methyl c sulfonic acid(AMPS)were adopted as the reactive monomers.(NH4)2S208+NaHS03 were adopted as the initiators.n(MA:AA:AMPS: Initiator)=0.5:1:0.019 :0.0089.Invitation temperature was 60?,dropping time of the initiators was 1.5 hours;continuous reaction time was 2 hours Using infrared spectrogram analysis synthetic product,the have a combination of three kinds of synthesis of the functional monomer,can clear product synthesis is the ternary copolymerization.Based on the effluence water quality analysis results and Oilfield chemistry theory,determine the calcium and magnesium ion concentration as anti-scaling agent evaluation index,and antiscale rate formula is used to change the antiscale effect of quantitative analysis.The anti-scaling agent under different conditions of water quality simulation experiment,synthetic antiscale effect of anti-scaling agent,indoor simulation experiment results show that: New type of antiscaling agent can effectively inhibit the formation of strong alkali asp flooding system scale,and distribution of anti-scaling agent effect is superior to the single type.