Desalter

A desalter is a process unit on an oil refinery that removes salt from the crude oil. The salt is dissolved in the water in the crude oil, not in the crude oil itself. The desalting is usually the first process in crude oil refining. The salt content after the desalter is usually measured in PTB - pounds of salt per thousand barrels of crude oil.[1] Another specification is Basic sediment and water.

The term desalter may also refer to a water desalination facility used to treat brackish water from agricultural runoff. This may be done either to produce potable water for human or animal consumption, or to reduce the salinity of river water prior to its crossing an international border, usually to comply with the terms of a treaty. Desalters are also used to treat groundwater reservoirs in areas impacted by cattle feedlots and dairies.

Why Desalt Crude?

The salts that are most frequently present in crude oil are Calcium,Sodium and Magnesium Chlorides. If these compounds are not removed from the oil several problems arise in the refining process. The high temperatures that occur downstream in the process could cause water hydrolysis, which in turn allows the formation of hydrochloric acid.Sand, Silts, Salt deposit and Foul Heat ExchangersWater Heat of Vaporization reduces crude Pre-Heat capacitySodium, Arsenic and Other Metals can poison CatalystsEnvironmental Compliance, i.e., By removing the suspended solids, which might otherwise become an issue in flue gas opacity norms, etc.,