残酸对原油脱水的影响及处理

酸对原油的破乳具有较大的影响,盐酸的存在使原油脱水发生困难,特别是在稠油中,脱水效率降低;土酸对原油脱水影响比盐酸更大,脱出水颜色发黑,发黄,有大量底渣存在;残酸对原油的脱水影响最大,脱水速度减慢,水色不清,过渡带加长.针对酸化后原油pH值较低的特点,选择碳酸钠作碱化剂,复配低温2#破乳剂,进行了室内实验和现场试验,结果表明:原油脱水效果明显,脱出水颜色清,油水过渡带清晰,保证返排液的pH值保持在6～8的范围内,使原油含水质量分数低于2%.

Treatment of residual acid and its influence on the crude oil dehydration

The residual acid has a great influence on the crude oil demulsion. The dehydration is very difficult and the dehydrated ratio decreased with the presence of hydrochloric acid, especially in the viscous crude oil. The clay acid had greater influence on the dehydration than the hydrochloric acid. The color of dehydrated water was black or yellow. There were many precipitates in the bottom. The residual acid had the greatest influence on the dehydration. The dehydration velocity decreased. The color of dehydrated water was not clean. The transition layer was thick. For the crude oil characteristics of lower pH value after acidization, some room and field experiments were done by using the sodium carbonate as alkaline agent and fixed with the demulsifier 2#. The results showed that the dehydrat effect was very obvious, the color of dehydrated water was clean and the transition layer was distinct. It also can be found that the PH-value is at the range from 6 to 8 and the mass fraction of water is less than 2%.