We are facing problems of detoriorating HCGO quality at higher unit throughput (108% of design). This is a coker having typical low recycle 8%. The HCGO CCR (typical 1.5 wt%)/ asphaltenes (typical 1500 ppm) are high and backwash frequency of Peter Ronnintgen filter (every 1 hour) in the downstream hydrocracker unit is also not ideal. We have conventional bubble cap/shed trays in wash zone of the fractionator.
We also find that backwash frequency of the filter increases tremendously by increasing above a particular threshold rate of HCGO in downstream hydrocracker unit.
Does any body has similar experience and if yes, what was done to mitigate the issue in the shortterm.
