Abstract:

The behavior of coking on catalyst and catalytic reforming reaction in a countercurrent CCR unit with a capacity of 600 kt/a in SINOPEC Jinan Branch Co. was investigated. The coke combustion characteristics were studied with TPO. The experimental results show that the countercurrent CCR process is a commercially feasible technology; compared to concurrent CCR, the temperature drop of the 1st reactor descended most and the distribution of temperature drop in reactors becomes even, and the total amount of coke generated in the 3rd and 4th reactor of countercurrent CCR, especially in the 4th reactor, increases sharply while the proportion of the coke in the 1st reactor decreases apparently. Different from concurrent CCR, the conversion of naphthene partly shifts from the 1st and 2nd reactor to the 3rd and 4th reactor. The conversion rates of paraffin in the 3rd and 4th reactor are slightly higher than that in the 3rd and 4th reactor of concurrent CCR mode; The olefin content in liquid products of the 3rd reactor reaches a peak value but declines in the 4th reactor; Compared to that of concurrent CCR, the coke burn-up temperature of countercurrent CCR rises.

Key words: countercurrent continuous catalytic reforming, coke deposition rule, reaction rule, TPO