关键词: 破乳剂, 高硫原油, 高酸原油, 大分子, 乳状液, 脱水

Abstract: This paper is focused on problems existing in dehydration process of inferior crude oil that is rich in oxygen, sulfur and other impurities. Element Si is introduced into the main chain of traditional demulsifier to improve the surface activity of demulsifier and eliminate the effect of stability that non-hydrocarbon compounds, such oxygen and sulfur, have on emulsified liquid. The emulsion will lose its stability by the effects of replacement while emulsion is formed in a structure of pectination by introducing a mass of branch chains, thus increasing steric hindrance of its film-forming and ensuring free movement of dispersive water drops. The characteristics of macromolecules improve demulsifier’s capacity to catch micro drops and its further dehydration effects. Based on the study of synergistic effect, the appropriate accessory ingredient is selected to compound with other demulsifier. As a result, the high-efficiency macromolecular crude demulsifier of D series is developed to solve the dehydration problems of high acidic and high sulfur crude oil, fulfilling the objective for further dehydration by lowering water cut of crude oil to less than 0.2 percent after dehydration. Demulsifiers of this series have been widely used in Africa’s oilfields, solving actual problems in production process and keeping oilfields in normal production.

Key words: demulsifier, high sulfur crude, high acidic crude, macromolecule, emulsion, dehydration