Hydrotreating Diesel Process by Axens

Application: Produce ultra-low-sulfur diesel (ULSD) and high-cetane and improved-color diesel fuel from a wide range of middle distillates feeds including large amount of cracked stock (such as LCO, light coker/visbreaker gasoils or MHC-GO, AR/VRDS GO) using Axens’ Prime-D Toolbox of proven state-of-the-art technology (including high activity/stability HR Series catalysts and high-performances EquiFlow internals) and services.

Description: In the basic process, as shown in the diagram, feed and hydrogen are heated in the feed-reactor effluent exchanger (1) and furnace (2) and enter the reaction section (3), with possible added volume for revamp cases. The reaction effluent is cooled by the exchanger (1) and air cooler (4) and separated in the separator (5). The hydrogenrich gas phase is treated in an existing or new amine absorber for H2S removal (6) and recycled to the reactor. The liquid phase is sent to the stripper (7) where small amounts of gas and naphtha are removed and high-quality product diesel is recovered.

Whether the need is for a new unit or for maximum reuse of existing diesel HDS units, the Prime-D Hydrotreating Toolbox of solutions meets the challenge. Process objectives ranging from low-sulfur, ultralow-sulfur, low-aromatics, and/or high-cetane number are met with minimum cost by:
• Selection of the proper combination of catalyst from HR Series and ACT grading materials for maximized cycle length and performance. HR 626 catalyst covers the range of ULSD requirements with highly active and stable catalysts. HR 626 CoMo exhibits high desulfurization rates at low to medium pressures; HR 538/HR 548 NiMo have higher hydrogenation activities at higher pressures.
• Use of proven, high-performance reactor internals, EquiFlow, that allow near-perfect gas and liquid distribution and outstanding radial temperature profiles (implemented in over 100 units).
• Loading catalyst in the reactor(s) with the Catapac dense loading technique for up to 20% more reactor capacity. Over 15,000 tons of catalyst have been loaded quickly, easily and safely in recent years using the Catapac technique.
• Application of Advanced Process Control for dependable operation and longer catalyst life.
• Sound engineering design based on years of R&D, process design and technical service feedback to ensure the right application of the right technology for new and revamp projects. Whatever the diesel quality goals—ULSD, high cetane or low aromatics—Prime-D’s Hydrotreating Toolbox approach will attain your goals in a cost-effective manner.

Licensor: Axens.