The water in crude oil is greatly harmful to preservation, transportation, quality of products, so dewatering and desahing of crude oil are very necessary for oil industry. Now in China most of the exploitation oil are paraffin base crude oil with high wax content, high solidifying point, high viscosity and bad fluidity in low temperature, which makes more difficult for oil-water emulsion system to demulsify. By the method of microwave radiation and addition of CH3COONa into sample, good dewatering efficiency was obtained. The rule of microwave-demulsification for high-wax crude oil, CH3COONa being applied as additive, was studied with orthogonal design method. The results showed that dewatering efficiency greatly improved in the presence of much less CH3COONa. By using SH9402 microwave system, the dewatering rate of Daqing high-wax emulsion containing 50% mass fractions of water was up to 95.83% under the conditions of microwave power 225 W, system pressure 0.7 MPa, isobarically time 12 min and m（CH3COONa）/ m（Oil） =0.05.
Acta Petrolei Sinica (Petroleum Processing Section)
paraffin base crude oil
orthogonal design method