摘要 |
A fluid catalytic cracking process and apparatus is described which includes a high temperature stripper (hot stripper) to control the carbon level and sulfur on spent catalyst, followed by catalyst cooling to control the regeneration inlet temperature. The high temperature stripper operates at a temperature between 100 DEG F. above the temperature of a catalyst-hydrocarbon mixture exiting a riser and 1500 DEG F. The regenerator inlet temperature is controlled to obtain the desired regeneration temperature, regenerator outlet temperature, and degree of regeneration. The regenerator is maintained at a temperature between 100 DEG F. above that of the catalyst in the high temperature stripper and 1600 DEG F. The present invention has the advantage that it separates hydrogen from catalyst to eliminate hydrothermal degradation, and separates sulfur from catalyst as hydrogen sulfide and mercaptans which are easy to scrub. The catalyst cooler enables the regenerator and high temperature stripper to be run independently at respective desired temperatures.
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