Flow distribution for monolithic reactors (Chevron)

CATEGORY: MONOLITHIC REACTORS 
Flow distribution for monolithic reactors (Chevron)

Type	Patent
Inventor	Krishniah Parimi
Inventor	Steven Xuqi Song
URL	Free Full Text Source:  http://www.google.com/patents/US20140183282
Assignee	Chevron U.S.A. Inc.
Patent Number	US20140183282 A1
Issue Date	Jul 3, 2014
Abstract	Systems, apparatus, and methods for distributing a mixed phase fluid to a monolith catalyst bed within a reactor, wherein a mixed phase fluid may be generated by a nozzle tray comprising a plurality of nozzles, the mixed phase fluid may be distributed by the nozzles to a mixed phase distributor system, and the mixed phase fluid may be further distributed by the mixed phase distributor system to a plurality of monolith channels within the reactor. BACKGROUND Conventional reactors containing packed beds of particulate solids are used in the chemical, petroleum refining, and other industries for a variety of different processes. Examples of such processes include: catalytic dewaxing, hydrotreating, hydrodesulphurization, hydrofinishing, and hydrocracking. In these processes a mixture comprising a liquid phase and a gas phase are typically passed over each packed bed within a downflow reactor. Monolithic reactors may also be used for various catalytic processes. Each monolith contains a multitude of parallel channels through which fluid reactants flow, wherein each channel contains or is coated with catalyst. Monolithic reactors provide a uniform and well defined flow path for reactants, resulting in low pressure drop, high flow rates and productivity, and increased catalyst life. Other advantages of monolithic reactors for refinery hydroprocessing include high geometric surface area, low internal diffusion, excellent gas-liquid-solid mass transport, high selectivity, high reaction rates, and ease of reactor scale-up. In the event of non-uniform distribution at the inlet to a packed bed reactor, some correction can occur due to radial diffusion during gas and liquid flow through the packed bed. In contrast, monolithic reactors do not allow radial diffusion; therefore, it is of critical importance to provide uniform flow distribution to the inlet of the monolith. U.S. Pat. No. 7,032,894 to Adusei, et al. discloses a device for distributing fluid into a monolith bed, the device including a plurality of flow channels stacked in order of decreasing diameter. The flow channels successively split a flow stream into multiple flow streams prior to the flow stream entering the monolith bed. There is a need for systems, apparatus, and methods for providing uniform fluid distribution to monolithic reactors for the efficient and safe operation thereof.