高频/高压脉冲交流电场破乳技术及其原油电脱盐应用研究

劣质原油的电脱盐预处理是当前炼油企业普遍面临的一个技术难题。通过系统介绍世界范围内原油乳化液电场破乳技术的发展历程,指出高频/高压脉冲交流电场应该引起国内业界的关注。实验室内可行性实验和工业侧线试验结果均表明,高频/高压脉冲方波交流电场的破乳效果优于常规工频/高压交流电场,获得最佳破乳效果的电场频率应该依据原油乳化液的具体理化特性(如水含量、乳化程度、破乳温度等)筛选确定,且一般在1 500 Hz以上。BIPTHFAC-Ⅲ型高频/高压脉冲方波交流电源的现场测试结果表明,在最佳电场频率区间内的电脱盐率均高于同期参照对象的平均电脱盐率,同时还能缩短水力停留时间以及节省加热成本。高频/高压脉冲交流电场破乳技术为炼油企业应对复杂劣质原油的脱盐难题提供了一条切实可行的解决方案,值得进一步开展工业应用研究。

RESEARCH OF ELECTROSTATIC DEMULSIFICATION TECHNOLOGY UNDER HIGH-FREQUENCY/HIGH-VOLTAGE PULSED AC ELECTRIC FIELD AND ITS APPLICATION IN CRUDE OIL DESALTING

Electric desalting pretreatment of low-quality crude oil is a difficult technology generally faced by refineries. This paper introduces the development process of demulsification technology of crude oil emulsion electric field in the world, and points out that the high frequency / high voltage pulse electric field should arouse the attention of the domestic industry. The laboratory feasibility experiments and industrial side-line tests indicate that the demulsification performance of high-frequency/high-voltage pulsed AC electric field with square wave is better than that of conventional frequency/high-voltage AC electric field, where the optimum frequency depends on the physicochemical properties of specific water-in-crude-oil emulsions, e.g. water content, emulsification degree, and demulsification temperature, and is generally above 1500 Hz. The field test results of home-made BIPTHFAC-III high-frequency/high-voltage pulsed AC electric power with square wave show that the desalting efficiencies within the range of optimum electrical-field frequency are all higher than the average desalting efficiencies of the simultaneous reference samples, and it can shorten the hydraulic residence time and reduce the heating cost. The high-frequency/high-voltage pulsed AC electric field electrostatic demulsification technology can provide a practical and feasible scheme for solving the difficulty of low-quality crude oil desalting.