Abstract: A FPSO in the South China Sea is used for the processing,storage and export of crude oil transported from five platforms. The high-pressure separator is the core of the crude oil processing system,and its separation efficiency directly determines whether the treatment of crude oil and production water is qualified. The larger the internal space of the high-pressure separator is,the longer the liquid residence time is,the better the oil-gas-water separation effect is. After replacing seawater with production water at around 84 ℃ for sand washing in the high-pressure separator,the sand accumulation inside the separator is effectively reduced,the sand washing procedure is simplified,and there is no longer need to use the shutdown overhaul time to clean the sand accumulation inside the separator separately.

Key words: transformation, sand washing, separator