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What is salt point at crude overhead?
 
Answers
22/03/2014 A: Eric Vetters, ProCorr Consulting Services, ewvetters@yahoo.com
The salt point is the temperature at which the partial pressure of the salt forming contaminants such as ammonia or amines and HCl exceeds their equilibrium limit (Kp). Kp is a function of temperature and increases with increasing temperature, which means that as temperature increases the allowable partial pressure of ammonia or amine and HCl before salt precipitation begins increases.
Salt formation in crude overhead systems leads to fouling and underdeposit corrosion. Some amine chloride salts will be above there melt point at crude overhead conditions, and they tend to cause very aggressive corrosion when they form.
Salt point for ammonium chloride can easily be calculated based on information in the public domain, but amine chloride salt points can only be calculated using proprietary databanks of amine thermodynamic properties.