Study On Synthesis And Demulsification Performance Of BGFAA/AA-BGFAA/BAHSPS

In the process of oil recovery,in order to improve oil recovery,a series of stimulation measures such as alkaline water flooding,fracturing,polymer flooding and so on are often taken,which leads to the composition and type of heavy oil produced fluid becoming more and more complex,and the water cut is constantly increasing,forming a very stable oil-water emulsion.Excessive water content of heavy oil will corrode refining equipment and transportation pipelines,which will not only cause economic losses,but even cause safety accidents.In actual production,heavy oil emulsion can be separated by adding demulsifier.However,the current conventional crude oil demulsifiers have some problems,such as poor universality and strong specificity,and its application in oil production field is narrow,which not only causes poor demulsification and dehydration performance,but also leads to the decline in heavy oil production and secondary pollution of water sources.Therefore,according to the characteristics of oil quality in different oil production plants,it is very important to develop special demulsifier for heavy oil to improve the economic benefits of oil fields.This topic is aimed at the problems of high content of resin and asphaltene in Chen Zhuang heavy oil in Shengli Oilfield,and difficult demulsification and dehydration.According to the principle of similar compatibility,two kinds of demulsifiers with multi-benzene ring structure were designed and synthesized,which enhanced the aromaticity of demulsifiers,facilitated the dissolution and diffusion to the interface of heavy oil emulsion,and promoted demulsification and dehydration.The main research contents were as follows:(1)Cardanol polyoxyethylene acrylate(BGFAA)was synthesized by direct esterification of acrylic acid(AA)and cardanol polyoxyethylene ether(BGF-10)with hydroquinone as polymerization inhibitor and p-toluenesulfonic acid as catalyst.The structure of the product was confirmed by FT-IR and 1H-NMR.The effects of n(AA):n(BGF-10),reaction temperature,reaction time,catalyst dosage and polymerization inhibitor dosage on the esterification rate of BGFAA were discussed.On this basis,the optimal esterification process parameters were obtained by response surface methodology:reaction temperature was 127?,When the reaction time was 5.2 h,n(AA):n(BGF-10)=1.6:1,catalyst dosage was 5%and polymerization inhibitor dosage was 0.6%,the esterification rate of BGFAA reached 93.23%.(2)Binary polymer demulsifier for heavy oil(AA-BGFAA)was prepared by polymerization of BGFAA and acrylic acid(AA)with azobisisobutyronitrile as initiator and toluene as solvent.The product structure was characterized by FT-IR and 'H-NMR,the relative molecular weight was measured by GPC,and the critical micelle concentration was measured by fluorescence spectrometer.The demulsification and dehydration performance of AA-BGFAA on Chen Zhuang heavy oil W/O emulsion was investigated.When the demulsification temperature was 60?,the demulsification time was 2 h and the dosage of AA-BGFAA was 500 mg/L,the dehydration rate reached 86.8%,and the oil content in the separated water was 195.7 mg/L.The visual and microscopic demulsification process of AA-BGFAA was studied,and the apparent viscosity of emulsion,oil-water interface and system stability were discussed.(3)Phenyl polysiloxane demulsifier for heavy oil(BAHSPS)was synthesized with BGFAA,allyl polyoxyethylene polyoxypropylene methyl ether(HMS)and phenyl hydrogen-containing silicone oil as raw materials.The effects of various factors on Si-H conversion and surface tension of BAHSPS were studied.The optimum synthesis parameters were determined by orthogonal test:reaction temperature was 110?,reaction time was 7 h,n(Si-H):n(C=C)=1:1.2,catalyst dosage was 20 ?g/g and solvent dosage was 35%.Under these conditions,the Si-H conversion was 93.26%.The structure and molecular weight of the product were tested by FT-IR,'H-NMR and GPC.The CMC of BAHSPS was 0.8g/L by fluorescence analysis and surface tension method.Under the conditions of demulsification temperature was 50?,demulsification time was 100min and demulsifier dosage was 0.8 g/L,the dehydration rate of BAHSPS to Chen Zhuang heavy oil emulsion reached 89.5%,and the oil content in the separated water was 186.4 mg/L.The demulsification performance of BAHSPS was compared with commercial demulsifiers SP169,HQ96-1 and YT100.The effects of BAHSPS on oil-water interfacial tension(IFT)and apparent viscosity of emulsion were studied.The stability of emulsion after adding BAHSPS was tested by Turbiscan Lab stability analyzer.POM took micro demulsification images,and the demulsification process and mechanism of BAHSPS were discussed.(4)The single agent screening and double agent compounding experiments of AA-BGFAA,BAHSPS and commercial AR3 6,SP169 and HQ96-1 demulsifiers were carried out.The AR36 and SP169 with better demulsification performance were screened out,and the demulsification experiments were carried out with AA-BGFAA and BAHSPS in different proportions.When the ratio of AA-BGFAA and AR36 is 2:1,at 90 min,50? and 0.5 g/L demulsification concentration,the dehydration rate reaches 91.5%and the oil content in the dehydrated water is 207.3 mg/L.The dehydration rate reached 94.3%when the compound ratio of BAHSPS and SP169 was 1.5:1,50?,demulsification concentration was 0.6 g/L and 90 min,and the dehydration rate increased to 95.1%after half an hour.When the proportion of SP169 is increased,the water quality becomes clear.When BAHSPS:SP 169 is 1:2,the oil content in the water decreases to 138.5 mg/L.