Seeking help: Dear senior colleagues in catalysis, does the slurry from the catalytic unit go into the main lift pipe for reprocessing? The same nozzle as the crude oil?

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Hello everyone. Our unit is a heavy oil catalytic cracking plant with a capacity of 2 million tons per year, featuring a coaxial reactor and regenerator. It was originally designed with a single lift pipe for heavy oil, but an additional lift pipe for light oil was added to the reactor as part of later modifications. Recently, due to the light nature of the raw materials, low bed temperature, and low air volume, a bias in the bed has also occurred. To increase the main lift volume, oil slurry reprocessing is put into use (a process was designed for this purpose but has never been utilized before); this process involves mixing the oil slurry with the feed oil in the main lift pipe before it enters the feed oil nozzle. Our slurry solid content is 6–9 g/l, and the reprocessing ratio of the recycled oil is 7–9% (with a solid content of 2–3%). I would like to know what the advantages and disadvantages are of feeding this slurry back into the feed oil nozzle of the main lift pipe What issues should be considered in process adjustments?