The Synthesis And Study Of Oil-soluble Viscosity Reducing Agent

As the continuous decline of conventional heavy oil output, heavy oil resource which was difficult to exploit become more and more attentive. Our country heavy oil reserves quite rich, theoretical exploration and development has achieved certain results. Viscosity of heavy oil is high and very difficult to mine, conventional water flooding recovery is generally low. Bamianhe block was exploited mainly by cyclic steam stimulation, the method of heavy oil that pipeline transported is heating, so economic cost increases. In order to save cost, avoid the condensate tube accident adding oil-soluble viscosity reducer in the heating transport at the same time to reduce viscosity and slow down resistance.Heavy oil of countries, the standards set by different, generally the use of classification criteria recommended by the United Nations Agency for Research on. More sensitive to the viscosity-temperature characteristics due to special composition of heavy oil, viscosity changes significantly as temperature differ a lot. Therefore, the exploitation of heavy oil is generally use of heat, steam drive, cyclic steam stimulation, fire-drive technology. That can also be used to transport cold sand mining heavy oil, just technology was not widely used in a certain degree, Typically mixing light oil was more used. Viscosity reduction of heavy oil emulsion is most frequently used method in using surfactants chemicals, the effect of viscosity reduction would be more ideal associated with the thermal recovery method. The key to exploitation of heavy oil emulsification and viscosity reduction is to choose the suitable emulsifier. the one is the alkali like Na2CO3、NaOH; the second is the surfactant, cationic, anionic, nonionic. Surfactants with a certain amount of cosurfactant would be higher than emulsifier surfactant.A large range of reduction is emulsion viscosity, simple of use; but the post-processing technique is very difficult so that cost much. That can avoid the shortcomings of emulsification with the development of new oil-soluble viscosity reducer. Long-chain esters which can be divided into homopolymers and copolymers was generally used. However, the mechanism of oil-soluble viscosity reducer is not fully understood. Several specific viscosity reducer. It does not meet pipeline requirements that several specific viscosity reducer can only be used in a block of oilfield.This article analysis the geology of Bamianhe block, heavy oil reservoir in Jiyang Depression, different characteristics of formation of traps are different. Migration phase, or a reservoir stage, the role thick changed of factors are still water washing, biodegradation, free oxidation. Connectivity systems which are widely distributed will lead to the large reserves of high viscosity in Jiyang depression. The composition of the heavy oil in Bamianhe block is very different, the content of heterocyclic and asphaltene is relatively stable. The group composition of heavy oil and chemical composition analysis showed that heavy oil contain the features of low saturated Fang, low saturated hydrocarbon.According to composition characteristics of heavy oil, that can evaluate different types of viscosity reducer on the market based on viscosity reduction of the standard. To put breaker of heavy oil into the constant temperature water bath until the temperature stability by adding viscosity reducer, and were measured with the Brookfield viscometer. Measures showed that the viscosity reduction of the effect is not obvious, indicating that the viscosity reducer is selective and narrow. To examine a variety of solvents and surfactants, and found the effect of dodecyl trimethyl ammonium bromide and solvent xylene was better, that can be reserved for the following subsequences. According to the research, to choose side chain ester polymer as viscosity reduer monomer. This article uses a direct esterification of synthetic esters, and considers the impact of various factors on the reaction yields.According to the analysis of the structure of heavy oil and the early literature research, to select maleic anhydride, styrene, acrylamide and alkyl side chain methacrylic acid dioctadecyl as a monomer. A certain percentage of the drugs are added organic synthesis equipment, and dissolved in toluene solution of initiator AIBN when elevating temperature. To design a four-factor and three-level orthogonal test program base of the monomers and dosage, and to synthesis the corresponding quaternary polymer as the proportion in turn. Adding the product to Bamianhe heavy oil, to determine the viscosity in use of Brookfield viscometer under the setting temperature. To examine the viscosity reduction rate according to the viscosity reducing effect, and obtained the best effect is the molar ratio combination of10:1.5:2.5:1, to make the appropriate adjustments so as to get the ideal combination for10:2:3:0.5. Trying mix surfactant and viscosity reducer to enhance the performance of viscosity reduction, by the effect known that the compounding effect of cetyl trimethyl ammonium bromide and viscosity reducer was well. Compound with the surfactant, the rate of viscosity reduction can reach50%under60℃.Although there is a certain understanding for heavy oil, the mechanism is still not clear, issue of poor liquidity is not resolved. To interpret the colloidal structure and chemical composition of the heavy oil from micro-perspective, and to analyze the interaction mechanism of heavy oil molecule and viscosity reducer molecule, and to find the key factor of viscosity reduction impacts. To develop a new oil-soluble viscosity reducer is very difficult, and less universal, but the prospect is wider.