Why are the locations of sulfidation and passivation different?
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In the hydrocracking unit, the reactor consists of two sections in series, and the catalyst used is of the molecular sieve type. Question: Why is the pre-sulfidation injection point located at the R101 inlet, and the passivation injection point at the R102 inlet? Can the injection point be set at the R101 inlet instead? LPG, oil, coal, and diesel hydrogenation design,
The first-stage catalyst is a refined material, not a molecular sieve, and does not require passivation. The second section is the molecular sieve, which needs to be passivated with ammonia.
According to what you said, it should be a series of sequential cracking processes. R101 is the refining reactor, and R102 is the cracking reactor. Both the refining agents and cracking agents require pre-vulcanization before use; therefore, a vulcanizing agent is injected before R101 to achieve sequential vulcanization. The cracking agent that has just been vulcanized has too high an activity; feeding it directly into the main feed oil can easily lead to excessive temperature rises, and the catalyst is also prone to carbon deposition. Therefore, passivation is necessary to temporarily suppress the activity of the cracking agent.