Abstract: The coke quench water system of the coking unit comprises three coke quench water tanks and one sulfur-containing wastewater tank. It continuously emits VOCS and odorous gases into the surrounding environment, particularly during the coke quenching stage of the coke drum. This results in severe ambient odors, environmental pollution and adverse impacts on the health of workers. ?This paper mainly analyzes the delayed coking process and the causes of VOCS emissions and the current status of VOCS treatment. Without altering the original coke quench process, technical modification was implemented by recovering tank top gas into low-pressure fuel gas, achieving enclosed treatment of VOCS, thereby eliminating fugitive VOCS discharge at its source.

Key words: delayed coking, coke quench water, VOCS treatment, technical modification