Abstract
Processing of lower cost “opportunity” crudes has become common practice among U.S. refiners. These cheaper crudes, however, in many cases do not come without higher associated processing costs. Several refiners have documented higher than expected chlorides in their atmospheric tower overhead systems when processing opportunity crudes. These high chlorides increase corrosion potential, elevate chemical treatment costs and, in severe cases, cause system failure and/or serious product contamination concerns.
Traditional methods to measure crude quality (salt content) have in some cases failed to predict potential hydrolyzable chlorides in the desalted crude stream. Laboratory desalter simulation apparati which operate at desalter system temperature and mixing conditions can be used to more completely extract water soluble chloride salts from the crude oil. Subsequent steam distillation of these laboratory desalted crude oils yields a truer measure of potential hydrolyzable chlorides left in the desalted crude. These tools have been used to better define the impact of processing opportunity crudes on crude distillation overhead systems.
