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Residue Hydrocracking based on Ebullated Bed
Delayed Coking
Technology
Delayed Coker is widely diffused for its maturity, flex- Residue hydrocracking is a catalytic cracking process that utilizes ebul-
ibility and ability to handle all kind of feedstocks. lated bed reactors to simultaneously achieve the metal and CCR re-
It is a thermal cracking process that provides a moval, desulfurization and conversion reactions.
complete rejection of metals and residual carbon as
coke and provides high yields of distillates.
Main advantages Main advantages
§ Move towards zero fuel oil production. § Quality of distillates

§ Lower capital investment § Marketable low sulfur fuel oil
Main disadvantages Main disadvantages

§ Coke storage and handling environmental is- § Hydrogen consumption
sues
§ Higher capital investment
§ Coke marketing (disposal)
§ Sediment control
Installed base Installed base
On a world-scale basis, presently approximately In last 25 years there were around 20 units built based on ebullated
one-third of installed residue upgrading is by delayed bed technology installed worldwide
coking

Table 1 Residue upgrading technologies comparison

Figure 1 Axens H-Oil™
Residue Upgrading
Process Scheme

Delayed Coking and Residue Hydrocracking have both intrinsic in Delayed Coking process mainly due to
supporters and detractors in the oil refining market. environmental issues related with the coke production
Supporters of the Delayed Coking highlight the reduced and storage and to the marketability of produced coke.
capital investments and fuel oil production minimization Both processes have significant technological and
and criticize hydrocracking for its high hydrogen operating critical aspects that requires specific
consumption, large investment requirements and the experience in design, construction, commissioning,
challenging sedimentation control. operation and maintenance. But while delayed coker
Factors supporting the choice of hydrocracking are the technology is widely diffused vacuum residue
high quality of the obtained distillates and the low-sulfur hydrocrackers are much less implemented in refineries
fuel oil market prospects, opposing to the difficulties and present serious challenges.

IndustrIal Plants - May 2017
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