Abstract: In order to solve the problem of mixing FCC slurry in delayed coking unit, the thermal reaction characteristics of FCC slurry were studied by using a heavy oil micro-thermal reactor. The results showed that the coke yield and gas yield of slurry were higher than that of the vacuum residue under the same reaction conditions, the product distribution of vacuum residue changed little with the reaction time increasing from 2 h to 4 h, and the coke yield of FCC slurry was decreased by 3.07 percentage points, which indicated that the more heat and higher reaction severity were needed in thermal reaction of FCC slurry. Through revamping the coking furnace of the industrial unit, the industrial practice of mixing FCC slurry with high severity was carried out. Under the condition of mixing FCC slurry, the conversion rate at the exit of coking furnace was increased from 8% to 12%, the yield of petroleum coke in the unit was reduced by 1.1 percentage points, and the volatile content of petroleum coke was reduced by about 2.1 percentage points, which indicated that the thermal conversion degree of feedstock was improved and the high severity condition was favorable for the deep conversion of slurry oil.

Key words: delayed coking, catalytic slurry, thermal conversion, coking furnace, product distribution