There are several methods to recycle oily sludges within the Delayed Coker. Processing a water slurry of these sludges during the water quench phase of the coke drum cycle was pioneered by Mobil Oil and was called MOSC for Mobil Oil Sludge Coking (at least that is what I think the abbreviation means). Another method is to inject an oil slurry into the coke drum either into the overhead of the drum or into the feed line downstream of the heater. Another method is to bring the dewatered oily sludge into the blowdown system to dry it out completely and then use the circulating oil from the blowdown system as overhead vapor line quench so that the oily sludge gets processed during the coking phase.
Veolia did a presentation back in 2006 about these various options. The address is listed below: http://refiningcommunity.local/presentation/process-solutions-oily-waste-processing-and-coker-injection-technologies/
Mitch Moloney of ExxonMobil did a presentation on sludge coking for one of the conferences. I think it was a CokingCoker conference back in 2004 or 2005. He listed the various methods of sludge coking and some of the processing rates. At that time ExxonMobil was licensing the sludge coking technology.
I am not aware of any other technology or significant improvements in the existing technology to recycle oily sludge into a Coker.
