Abstract: The effect of MPTA agent on the demetallization of Daqing and Jidong mixed crude oil was evaluated in laboratory, and the commercial trial was carried out in the electric desalting device of the No.2 atmospheric-vacuum distillation unit at Beijing Yanshan Company, SINOPEC. The results of batch scale lab test showed that good demetallization performance could be obtained at a MPTA added dosage of 80 μg/g. The commercial test results showed that at a MPTA added dosage of 60 μg/g, the removal rates of calcium, sodium, magnesium, iron and nickel were 82.20%, 98.96%, 91.90%, 58.65% and 24.23%, respectively. Meanwhile, the acid value of treated mixed crude oil could be less than 0.5 mg KOH/g without significant change.

Key words: mixed crude oil, electric desalting, demetallization agent, removal rate