Optimal processing parameters of electrostatic crude oil desalting

Abstract

Crude oil often contains dilute dispersion of ultrafine water droplets with a variety of salts, solids and metals. To prevent corrosion, plugging, and fouling, electrostatic desalting plants are often installed in oil production units in order to remove water-soluble salts from the oil stream. To meet business requirements, the salinity of the crude is limited to less than 40 mg /l and (BS&W) Basic Sediments and Water must to be lower than 1%.

This work presents the results of an experimental study conducted regarding the variation of important processing parameters, namely: the rate of wash water, demulsifier amount, and processing temperature in aim to reach the optimum of each of those parameters and then to obtain the lowest values of oil salinity and (BS&W).

Experiments conducted in the two-stage electrostatic desalter of South Crud Treatment Unit (UTBS/HMD/Algeria), showed that the Salts Removal Efficiency (SRE) increases with the increase of wash water rate, demulsifier amount and processing temperature. For 2% of wash water rate and 15 ppm of demulsifier for each stage at 70°C, the (SRE) was 95.78% and the final salinity value of treated oil was 11 mg/L. The mean value recorded for (BS&W) during experiments was only 0.05%