Self-optimizing control for hydrogen optimization in a diesel hydrodesulfurization plant

Abstract The aim of this work is to apply the self-optimizing control technique ( Skogestad, 2000 ) in order to ascertain the plantwide control structure for a hydrodesulfurization HDS plant of a petroleum refinery with regards to hydrogen consumption optimization. The resulting control structure for the HDS plant is simple, robust to uncertainty, easy to implement (feedback control) and assures the global optimum in most cases, although an upper RTO layer will be needed to guarantee the operation in the adequate region, with non frequent updates. Only in one uncommon scenario a trade-off arises regarding the unconstrained degrees of freedom, and self-optimizing control variables must be looked for. Potential application to global refinery H 2 network is also discussed.