Patent ID: 6485578
Filing Date: 2002-11-26
Classification: B08B,C10G,F28G

Abstract:
A chemical cleaning process for removing fouling from process lines of oil refining or petrochemical plants, in which the process lines are in an on-line state, comprising:introducing a cleaning agent into the process lines with discharging of crude oil already filled in the lines, said cleaning agent comprising 2 to 20 vol. % of a cleaning composition comprising 0.01 to 1 wt % of a C8 aromatic compound, 75 to 85 wt % of a C9 aromatic compound and 14 to 24 wt % of a C10 aromatic compound, and 80 to 98 vol % of a light cycle oil (LCO) or a light gas oil (LGO); circulating the cleaning agent through the process lines and increasing the temperature of the cleaning agent by use of a heating source to remove fouling in the process lines; and monitoring the light transmittance of the circulating cleaning agent with the aid of a near-infrared analyzer to determine whether the cleaning of the process lines is completed.