Simulating experiments on catalytic cracking and thermal cracking reactions in riser reactor

Thermal cracking and catalytic cracking reactions which occurred in riser reactors were studied using a pilot riser-type fluid catalytic cracking unit.The effects of residence time,reaction temperature and catalyst/oil ratio on thermal cracking and catalytic cracking reactions were also investigated in detail.Optimization on the operation conditions of residuum fluid catalytic cracking(RFCC) process with high-temperature,high catalyst/oil ratio and short residence time was carried out.The experimental results show that shortening residence time and increasing catalyst/oil ratio can decrease thermal cracking reactions in riser reactor and increase light oil yield.Properly high temperature in riser reactor can increase ligh oil yield,but too high temperature will lead to worse product distribution.Under the operatin conditions of higher temperature and catalyst/oil ratio,shortening residence time to suppress undesirable thermal cracking is the key to obtain better product distribution in RFCC process.