The crude oil and water are simultaneously mixed through two-by-two division, cross-current mixing, and back-mixing, improving turbulence and increases mixing efficiency without requiring high fluid shear velocities. The modified desalter system can operate on 14 in. and 22 in. API naphthenic crudes, with less that 5% oil in the effluent water.
Depending on the type of crude oil, the refiner can remove between 5% and 10% more salt than by the mix valve method. The results cause less corrosive HCI generation in the crude unit furnaces. It also requires less ammonia to neutralize the atmospheric column overhead stream.
The mixer helps reduce emulsions formed by too much pressure drop created by the mix valve. The less oil carry under, the less fuel is consumed from having to reheat recycled oil up to 300 degree F before it re-enters the crude unit.
Komax Systems Inc., P.O. Box 1323, Wilmington, CA 90748. Tel: 310-830-4320; Fax: 310-830-9826.