Abstract: In view of the poor removal effect of coke powder by the traditional herringbone baffle in the desuperheating section of coking fractionator of delayed coking unit, which results in a large amount of coke powder entering into coking gas oil and coking diesel oil, resulting in unqualified products, water-air-coke powder and coking gas oil-oil-gas-coke powder systems were used to simulate the removal of oil-gas coke powder by spraying water and oil droplets with three sprinklers respectively. The results showed that the best arrangement of the three sprinklers was the triangle with the ratio of the distance between the sprinkler and the column center（r） and the column radius（R）of 0.56. Under the conditions of the liquid spray density of 2 m³/(m²·h) and the high gas load, the coke removal rate of single-layer multi-nozzle single-way (S-T-S) spray water droplets was about 3% higher than that of single-layer single-nozzle single-way (S-S-S) spray water droplets, and the average coke removal rate of S-T-S and S-S-S spray oil droplets was more than 98.4%. The minimum coke removal rates of S-T-S spray and S-S-S spray oil droplets were 10.57% and 11.43% higher than those of corresponding spray water droplets, respectively, which indicated that the effect of removing coke powder by spray oil drop washing was better than that by spray water drop washing. The results of commercial application showed that the product quality of side-line of coking fractionator could be improved obviously by using the multi nozzle spray oil droplet technology.

Key words: delayed coking, coking fractionator, coke powder, spray technology, kinetic energy factor of empty tower, removal rate