ABSTRACT
Coking processes are severe thermal conversion processes during which part of the feed material is converted to lighter products and part of the material is converted to petroleum coke, or petcoke. Coking is used primarily to pretreat vacuum residuals to prepare coker gas oil streams suitable for feed to a catalytic cracker. Coking technology can be divided into two main classes based on reactor design, namely, delayed coking and fluid coking. When a coke drum is switched from reaction mode to cleaning mode, the hot material from the furnace that just entered the coke drum had little residence time in the coke drum. The decoking operation is accomplished in some plants by a mechanical drill or reamer, however, most plants use a hydraulic system. Fluid coking technology can be implemented with or without a gasifier in the process design. The effect of solids present in oil is to delay the observed onset of coking.
