Grey Correlation Analysis of Corrosion on Oil Atmospheric Distillation Equipment

Corrosion exacerbated on atmospheric distillation unit when Shengli plant refined high-sulfur and high-acid crude oil imported from Middle-east. Measured the corrosion pate on the top of atmospheric distillation tower with electric resistance probe and monitored sulfur value, salt value, salt value after desalt, acid value in crude oil and iron ion in product container every month. Carried on grey correlation analysis, calculated absolute, relative and synthetic degree of incidence, carried on predominance analysis too. The conclusion is that the main factor to corrosion is salt value after desalt, and then is content of iron ion, salt, acid and sulphur. Getting rid of salt from crude oil as possible is benefit to protect equipment, monitoring salt value after desalt or content of iron ion to adjust the quantity of water, ammonia and corrosion inhibitor added into oil is feasible.