Reasons for the significant loss of catalyst in catalytic cracking units

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This post was last edited by kn on 2020-6-8 at 11:07. In recent years, the N sets of catalytic cracking units at China National Petroleum Corporation’s Dalian Petrochemical Company have faced the problem of high catalyst leakage rates; the natural leakage rate reaches 2 kg/t, and in severe cases it exceeds 2.5 kg/t. This results in operations at low material levels or even “zero” material levels, which leads to two problems: first, the driving force in the regeneration pipelines decreases, and the fluidization of the catalyst in the inclined tubes becomes unstable, making fluidization prone to interruption. This reduces the ability to cope with risks in emergency situations and increases the severity of operational issues； The gradual increase in consumption not only raises the operating costs of the equipment but also accelerates the wear and tear on key components such as flue gas turbines, preventing the equipment from functioning properly. Through a series of operational tests conducted in the regenerator, an internal renovation plan for it was established: the main air distribution pipe in the second dense phase was changed from a circular tube to a three-leaf tube, and the shape was modified to an inverted L. The separator replaced the coarse cyclone separator. Use a PLY cyclone separator and a weight valve. After the transformation, the natural runoff loss of the catalyst was reduced to 1.0 ok g/t; energy consumption was decreased by 10%, and the consumption of combustion aids was reduced by 50%. The operating mode of the reaction regeneration system changed to steam.