【作者】 冯涛；

【导师】 王宝辉；

【作者基本信息】 大庆石油学院 ， 应用化学， 2007， 硕士

【摘要】 本论文综述了原油破乳剂的发展，并在国内外已有的研究基础上，针对低温下采出液破乳难度增加、破乳后水相含油量上升等问题，开展了低温破乳剂的特性研究工作，目的是研制出适合于高含水不加热集油和脱水的低温破乳剂，实现不加热脱水，同时降低油水分离后污水含油量，确保脱水的稳定，从而达到联合站原油低温集输处理、节能降耗的目的，满足实际生产的需要。研制成功的低温破乳剂是实现低温集油和低温脱水的关键技术之一，通过实施低温集输技术，不仅可以节约大量能源，提高设备处理效率，对今后油田高含水后期不加热集油和脱水技术在油田的推广也具有重要的意义。本研究分八部分内容。首先从低温下采出液物理化学特性、低温下原油乳化特性、低温下不同油水组成的粘温关系、低温下油水分离特性、低温下破乳剂破乳机理研究及沉降试验等方面开展了系统性的研究工作，在研究过程中：(1)通过测定采出液化学组成、天然乳化剂的性质和行为、在低温下不同油水组成的粘温曲线等，研究出了采出液在低温下物理化学特性，提出高于原油凝固点3-5℃不同油水比的粘度特征、采出液化学组成、天然乳化剂的性质和行为等；(2)通过测定低温下原油乳化类型、油相、水相和过渡层的结构、组成、天然乳化剂在低温下界面行为、乳化机理等，研究出了低温下原油的乳化特性；(3)通过测定低温下油水分离时间、分离效果、过渡层大小等数据，研究了低温下油水分离特性，提出高于原油凝固点3-5℃的油水分离特性，给出了油水分离时间、分离效果、过渡层大小等数据；(4)通过测定低温下加入破乳剂的油水分离时间、分离效果、过渡层大小等数据，以及低温下加入破乳剂后油水乳化类型、油相、水相和过渡层的结构、组成、低温破乳剂在低温下界面行为等，研究了低温下破乳剂破乳机理，从而指导了低温破乳剂的研制工作。在上述工作的基础上，开展了低温破乳剂的评价方法、配方研制以及现场试验工作：(1)研究开发的低温破乳剂DE1036，经现场试验表明，在其加药浓度为≤15mg／L条件下，脱后污水含油量、油相含水量、外输油含水达到了开题报告提出的技术指标要求，其综合性能优于现场破乳剂，是一种性能优良的低温破乳剂；(2)对于大庆油田高含水采出液的破乳脱水温度为34～37℃，脱后污水含油量降低到350mg／L以下，外输油含水率≤0.3％，电化学脱水稳定，经济效益显著，具有广阔的推广应用前景；(3)低温破乳剂DE1036的成本与常规破乳剂相同，无需增加成本。新研制的低温破乳剂DE1036降低了脱水温度，有效地降低采出液处理成本，达到了显著节能效果，取得经济效益为956.38万元；(4)该剂可在大庆油田高含水采出液的油水分离中应用，解决低温脱水生产技术难题，其技术达到了国内领先水平。研制的低温破乳剂与低温集输现场试验项目配套使用，可确保低温集输技术在油田全面推广应用，对降低原油脱水温度，以及节约原油脱水生产成本具有重要意义。因此，项目研究的成果推广应用前景广阔。更多还原

【Abstract】 In this paper, the development of demulsifiers for breaking crude oil emulsionat was summarized.Based on the research on demulsifiers for breaking crude oil emulsionat low temperature in the world, Inthe face of the difficulties of crude oil demulsification at low temperatures such as tight emulsion and highoil carry-over, study on ’the Formulation and application of Demulsifiers for Breaking Crude OilEmulsion at Low Temperature’ was conducted. In this study, demulsifiers were characterized at lowtemperatures to screen and formulate demulsifiers that were suitable both for the demulsification of thehigh water-cut crude oil emulsion gathered and treated at low temperatures to remove the heating processesinvolved in oil gathering and treatment at production stations and to lower the oil carry-over in producedwater. The demulsifiers thus formulated played an important role in the low-temperature gathering andtreatment of crude oil which can be adopted to save a large amount of energy. The demulsifiers also helpedto increase the capacities of crude and produced water handling facilities.The study consists of 8 major parts. The starting parts cover the physical and chemical properties ofproduced liquid, emulsification of crude oil at low temperature, viscosities of crude oil emulsion of variouswater-cuts at low temperatures, oil/water separation performances at low temperatures, mechanismsinvolved in low temperature chemical demulsification and benchtop gravity settling treatment of producedliquid at low temperatures. The rheological characteristics of crude oil emulsions of various water-cuts attemperatures 3 to 5 degree Centigrade above the pour point of crude oil, composition of produced liquid,characteristics and performances of natural emulsifiers in the crude oil were presented based on the studieson the produced liquid composition, characteristics and performances of natural emulsifiers in the crudeoil, viscosities of crude oil emulsion of various water-cuts at low temperatures. Emulsification tendenciesof crude oil at low temperature were described by means of emulsion pattern, structure andcomposition of the transitional layer between oil phase and water phase, characteristics and performancesof natural emulsifiers in the crude oil, and the mechanisms of emulsification. Oil/water separationperformances at temperatures 3 to 5 degree Centigrade above the pour-point of crude oil,such as the timerequired for oil/water separation, oil/water separation performance, ratio of the transitional layers, werepresented based on the study of oil/water separation performances including determination of oil/waterseparation time, separation performances, and ratios of transitional layers. Mechanisms involved in crudeoil demulsification at low temperatures were studied by means of the determination of oil/water separationtime, separation performances, ratios of transitional layers under the effects of demulsifiers at lowtemperatures, as well as the determination of emulsion pattern, structure and composition of the transitionallayer and the interfacial properties at low temperatures in the presence of demulsifiers. The mechanismsthus presented were used as guides in the formulation of demulsifiers for low temperature demulsificationof crude oil.Establishment of the evaluation methods, formulation and field trial of demulsifiers for lowtemperature crude oil demulsification were conducted based on the studies mentioned above. A demulsifierfor low temperature crude oil demulsification, named DE1036, was formulated. Field trial showed thatDE1036 was a very good demulsifiers for low temperature crude oil demulsification and oil carry-over ofproduced water, water-cut of crude oil emulsion and water-cut of exported crude oil all met the technicallimits specified in the study proposal with a dosage of DE1036 at 15mg/l. The new demulsifier showed much better performance than the incumbent demulsifier applied at the field trial site. The demulsifierDE1036 shows a broad application as it can be adopted in such cases as high water-cut Daqing crude oil,free water knockout temperature at 34 to 37 degree Centigrade to get the separation performance of oilcarry-over of produced water below 350mg/l and water-cut of exported crude oil not more than 0.3％withstable electro-dehydrator operation. Replacing the state-of-art demulsifiers with DE1036 will not result inany cost increase as the price of demulsifier DE1036 is the same as those of the state-of-art demulsifiers.Application of DE1036 brought out an economical profit of 9.5638 million RMB due to the reduction ofthe temperature and thus cost of produced liquid and saving of energy. The new demulsifier DE 1036 is in anationally leading status as it can be applied in the oil/water separation of high water-cut produced liquid todebottleneck the low temperature dehydration of crude oil. The demulsifier DE1036 can be combined withthe low temperature oil gathering technique to enhance the application of low temperature oil gathering.Itwill experience a broad application as it contributes to the reduction of temperature and cost of crude oildehydration.更多还原