Abstract: Thermal treatment of crude oil is one of the effective means for improving the flowability of waxy crude oil at room temperature as has been proved by oru experimental studies of more than ten crude oil samples(including Daqing crude oil)and by our many year’s application in several oil pipelines. Up to now however, the mechaniam of thermal treatment process for waxy crudes has not been well studied. Although it has been recognized that the proportion of the content of paraffin wax and resinasphaltene in the crude oil isthe main cause determining its rheological properties and its thermal treatment behavior, a satisfactory quantitative explanation is still laching. In this paper, based on experimental studies of thermal treatment for two typical waxy crude oil samples and Theological measurement data, the role of composition of crude oil, such as resin-asphaltene, paraffin wax-normal Paraffin and microcrystal wax in determining the efficiency of thermal treatment is discussed. It has been proposed that the ratio of resin-as-phaltene content to normal paraffin content in the crude oil may be taken as an indicator in efficiency prediction of thermal treatment of crude oil, With 0.6～3.0 as the best range to obtain the optimum result.

摘要： 本文研究了大庆、南阳原油中的胶质—沥青质,石蜡—正构烷烃和微晶等组分在含蜡原油热处理过程中的作用,从而指出:(1)只有当原油中含有石蜡和适量的胶质—沥青质时,才具备用热处理方法来改善其低温流动性能的可能性。(2)胶质—沥青质在含蜡原油中具有非常显著的分散作用增粘作用。它们通过吸附、共晶等作用改变原池中石蜡的结晶习性、形态及结构强度,从而取得降凝、降粘等效果。(3)各种原油中胶与正构烷烃之比在0.43～5.2之间,经过最佳条件热处理就可显示出热处理效果。胶—正烷烃比在0.6～3.0之间热处理效果最佳。(4)微晶蜡在含蜡原油热处理过程中,其本身不能显示热处理效果,当加热温度高达微晶蜡能在原油中大量溶解的温度时,在降温重结晶过程中,微晶蜡的析出将恶化热处理效果。