Method and device for enhanced metal and amine removal from crude oil with controlled electrostatic coalescence

摘要

A method for removing metals, amines, and other impurities from crude oil in a desalting process that includes the steps of adding a wash water to the crude oil; adding the wash water to the crude oil to create an emulsion; adding to the wash water or the emulsion at least one water-soluble hydroxyacid; selecting the hydroxyacid additive from the group consisting of glycolic acid, gluconic acid, C.sub.2-C.sub.4 alpha-hydroxy acids, malic acid, lactic acid, poly-hydroxy carboxylic acids, thioglycolic acid, chloroacetic acid, polymeric forms of the above hydroxyacids, poly-glycolic esters, glycolate ethers, and ammonium salt and alkali metal salts of these hydroxyacids, and mixtures thereof; resolving the emulsion containing the crude oil, wash water, and hydroxyacid additive into a hydrocarbon phase and an aqueous phase using electrostatic coalescence, the undesired impurities being transferred to the aqueous phase; measuring the characteristics of one or more of the resulting crude oil output, effluent waste, and/or other intermediate points; and altering one or more characteristics of the desalting operation as a function of the measurements. Various oil desalting configurations are also provided.