INSIGHTS ON REACTOR INTERNALS FOR ULSD – PERFORMANCE OF EXISTING AND NEW HARDWARE

Description:

Producing ultra-low sulfur diesel (ULSD) poses significant challenges within the hydroprocessing reactor. At deep desulfurization levels, reaction kinetics are lower order and deviations from plug flow are more detrimental. Required gas circulation rates are higher, due to increased hydrogen consumption, which in turn results in larger exotherms and potentially complete vaporization of the reactants. Therefore, the reactor internals must be able to perform well over a very wide range of vapor-to-liquid ratios to take full advantage of today’s high activity catalyst systems. This paper provides the refiner with insight on assessing whether their existing internals, or those that they are considering, can adequately address these challenges. This insight has been gained through both troubleshooting of existing hardware and through R&D efforts, using mathematical models and computational fluid dynamics (CFD).