Experiences in coker unit operation

الملخص EN

Kuwait National Petroleum Company (KNPC), Mina Abdulla Refinery (MAB) had installed and commissioned in 1988 two identical Delayed Coker Trains each requiring 30000 BPSD of Vacuum resid as feed.

The requirement for a Delayed Coker Unit at MAB Refinery was envisaged with a view to achieving zero production of low value heavy fuel oils while increasing production of more valuable lighter distillate with the generation of coke as a byproduct.

Coker liquid products are further hydrotreated to meet product specifications.

The special feature of the MAB Cokers are the processing of hydrotreated vacuum residue feed stock, fractionator bottom side filters, the hydrocarbons recovery and water reuse systems.

Since initial commissioning of the Delayed Coker Unit, MAB Refinery had experienced several operating problems.

These include the following: • Shorter heater run length • Coke drum vapor line fouling • Plugging of steamout system condensers • Plugging and corrosion in water reuse system • Lower than expected coke quality.

The refinery has carried out several trials to overcome the above problems and improve the quality of coke produced, to meet the Anode Grade Green Coke specification.

The plant trials include changes in operating conditions and procedures as well as hardware modifications.

Furthermore, the implementation of Advanced Computer Control Strategies resulted in smooth operation and improved liquid yield on a sustained basis at the most optimum operating conditions.

Details of the above are discussed in this paper