Nitro compound hydrogenation reaction process and hydrogenation reaction apparatus

A hydrogenation reaction process, comprising a hydrogenation step, a regeneration step, an activation step, and a recycling step, wherein:

• in the hydrogenation step, nitrobenzene as a reaction raw material is contacted with hydrogen gas and a hydrogenation catalyst in a hydrogenation reactor to obtain aniline and a spent catalyst, wherein the hydrogenation reactor is a fluidized bed reactor, the hydrogenation catalyst is a copper-based catalyst comprising copper as a main active component supported on alumina or silica, and a full inventory of the cooper-based catalyst in the hydrogenation reactor is in contact with the reaction raw material;
• in the regeneration step, the spent catalyst is regenerated in a fluidized bed regeneration reactor to obtain a regenerated catalyst;
• in the activation step, the regenerated catalyst is activated in a fluidized bed activation reactor to obtain an activated catalyst;
• and
• in the recycling step, the activated catalyst is recycled to the hydrogenation step, wherein the process further comprises:
• at least one hydrogenation degassing step of degassing the spent catalyst between the hydrogenation step and the regeneration step,
• at least one first regeneration degassing step of degassing the regenerated catalyst between the regeneration step and the activation step,
• at least one second regeneration degassing step of degassing the regenerated catalyst between the regeneration step and the recycling step,
• at least one activation degassing step of degassing the activated catalyst between the activation step and the recycling step,
• and
• a catalyst supplement step comprising introducing a supplement hydrogenation catalyst to the activation step,
• wherein the particle volume fraction in the unit of % in the transportation pipeline of the spent catalyst being transported from the hydrogenation step to the hydrogenation degassing step is C1, the particle volume fraction in the unit of % in the transportation pipeline of the spent catalyst being transported from the hydrogenation degassing step to the regeneration step is D1, the particle volume fraction in the unit of % in the transportation pipeline of the regenerated catalyst being transported from the regeneration step to the first regeneration degassing step is C2, the particle volume fraction in the unit of % in the transportation pipeline of the regenerated catalyst being transported from the first regeneration degassing step to the activation step is D2, the particle volume fraction in the unit of % in the transportation pipeline of the activated catalyst being transported from the activation step to the activation degassing step is C3, the particle volume fraction in the unit of % in the transportation pipeline of the activated catalyst being transported from the activation degassing step to the recycling step is D3, the particle volume fraction in the unit of % in the transportation pipeline of the regenerated catalyst being transported from the regeneration step to the second regeneration degassing step is C4, the particle volume fraction in the unit of % in the transportation pipeline of the regenerated catalyst being transported from the second regeneration degassing step to the recycling step is D4, the particle volume fraction in the unit of % in the transportation pipeline of the regenerated catalyst or the activated catalyst being transported from the recycling step to the hydrogenation step is C6, and wherein C1, C2, C3, C4, and C6 and D1, D2, D3, and D4 are in the range of 0.5-5%,
• wherein the hydrogenation reactor comprises a dense phase reaction zone, at least one dynamic pressure measuring point is mounted on the side wall of the dense phase reaction zone to measure an instantaneous pressure fluctuation in the dense phase reaction zone, and
• the catalyst supplement step is initiated when the standard deviation of the instantaneous pressure fluctuation is greater than 600 Pa, or when the catalyst particles having a particle diameter of less than 100 μm account for greater than 3 wt % by mass percent of all catalyst particles in the dense phase reaction zone.