| There are some general problems on crude oil which is high content and easy to solidify in the pipeline transportation.In the crude oil extraction and pipeline transportation process,the major safety problems are poor cold flow properties of crude oil,three-dimensional network structure of wax crystals and it is difficult to restart once the transportation stopped.It is a continuous process to keep good flow ability in the entire pipeline area.Curding in low temperature is a common phenomenon.If not controlled by outside factors,it will bring some difficulties not only for pipeline transportation but also for exploration and exploitation of oil resources.Besides,it may damage the integrity of the pipeline laying equipment,waste of manpower and property,endangering pipeline natural surroundings.In the harsh natural conditions,traditional depressant not only have a serious impact on the pipelines,but also labor-intensive or material,which not conform the spirit of the energy-saving economy.The new pour point depressant emulsion is the ideal effective solution to the above problem,the material is liquid,and crude oil has good compatibility similarity like diluents,which in the case of crude oil solidified adding trace can make solidification of crude oil continues to flow at normal temperature,solidification occurs only at lower temperatures.The article describes an emulsion type depressant,which can restore liquidity crude oil pipeline at low temperatures,saving energy consumption,do not require extensive use,easy to operate,and non-corrosive pipe wall.It compounded pour point depressant emulsion synthesized by emulsification basic raw material,thereby forming a water-in-oil emulsion structure,the impact of the crystallographic orientation of wax molecules and improve the low temperature fluidity of crude oil.Emulsion depressant for pipeline transport work is safe,economical and reliable method for long-term governance.Ethylene-vinyl acetate copolymer(EVA)is a kind of effective pour point depressant main component,which our country each origin of crude oil PPD has selectivity.This article research preparing PPD in the mixed oil of liangnan,which EVA has significantly pour effect for the mixed oil of liangnan.The focus of research is improved EVA PPD to effectively act on the mixed oil of liangnan.The experiments have two major sections.One is prepared PPD emulsion,the other is evaluated the PPD emulsion.To obtain the EVA dispersed system of solid highly stable,EVA were firstly dissolved in appropriate solvents and emulsified in the presence of composite emulsifier to reach the form of oil-in-water emulsion,phase transfer reagent were added into the emulsion to get the final product.The optimized condition for EVA emulsification is OP:AOS= 1:5(w/w),EVA:compound emulsifier= 2:1(w/w),stir at 80℃,700 rpm for 30 min.After emulsion cooling down,a certain amount phase transfer reagent is adding into the mixture to stratify it and obtain EVA emulsion.Advantage of the emulsion is a high stability and good dispersive,which can continued reduce solidifying point of crude oil 11℃ in mixed oil of liangnan.In accordance the principle of emulsifier,it chosen a variety of emulsifier form different HLB dubbed EVA emulsion effective emulsifier,which single factors way to control the variable and respectively discussion of different synthesis conditions,such as add water,the way of add,stirring rate,emulsifying temperature and other effects on the emulsion performance.It was evaluated which the stability of the emulsion was centrifuged,dispensability,particle size,low-temperature stability,etc,to determine the nature of the emulsion. |
PDF Full Text Request