Abstract
World crude oil supplies are getting heavier, and increasing in sulfur, nitrogen, oxygen and other non-hydrocarbon components. Corrosion problems are increasing due to the difficulties in desalting Maya and other heavy crudes.
To confront these corrosion problems we must examine the factors that make crude oils heavy and their impact on the basic chemical, physical and electrical principles of traditional desalting operations.
The increasing corrosion problems are not new problems in kind, but rather are primarily a continuation of already-encountered problems at a new order of magnitude. Heavy crude oil components are challenging the fundamental principles of traditional desalter designs. Increasing amounts of troublesome chemical species in the heavy crudes are presenting complicating emulsion problems with which current demulsifier chemistries are hard pressed to cope.
As a result, more corrosion-causing materials are getting past the desalter to do damage in refinery units. As refineries go "deeper into the barrel" to crack heavy crudes into lighter products to meet market demands, corrosion problems are being seen farther into downstream processing units such as FCCU gas recovery plants, reformers, desulfurization and auxiliary sour gas processing equipment.
Solutions to these increasing problems are not available in the currently- available technology, although some hardware modifications and more careful attention to chemistries - and a "cushioned" blending approach most refiners are now practicing to soften the problems - can provide some interim relief until new solutions are found.
