First published in PTQ&A Q3 2022
Dinesh-Kumar Khosla, Global Market Manager Heavy Ends, HDC, Axens
In units featuring fixed-bed reactors, along with optimum catalyst design, overall reactor/catalyst performance can be enhanced using high-efficiency reactor internals. Axens’ proprietary EquiFlow® reactor internals ensure a uniform gas/liquid distribution and optimum mixing in the reactor, thereby minimising channelling and hot spots to ensure optimal use of the entire catalyst inventory in the reactor.
This enhances catalyst activity, selectivity, and stability, minimising catalyst change-out frequency while ensuring safe and reliable operation. EquiFlow® distributor trays employ a dispersive system located below a chimney tray to ensure close-to-ideal vapour/liquid distribution throughout the catalytic bed underneath.
EquiFlow® quench systems (i.e., the proprietary Hy-Quench-XM and Hy-Quench-NG) feature a more compact design. This results in smaller reactors in grassroots configurations and increased catalyst volume for existing reactors. These quench systems provide higher thermal efficiency over a wider range of operating conditions.
These systems result in longer catalyst cycles and/or higher throughput operation.
For reactors prone to fouling, the EquiFlow® smart filtering tray system (i.e., proprietary Hy-Clean™) limits recurrent pressure drop problems while ensuring a perfect gas/liquid distribution in reactors. It will prevent plugging of the bed by catching and retaining feed impurities that are often responsible for crust formation between the different catalyst layers. Notably, with the use of Hy-Clean™, there is no additional pressure drop compared to conventional distributors or quench systems. Overall, Hy-Clean™ will enable a significant increase in catalyst cycle length, leading to higher profitability.
The right combination of catalyst and reactor internals is thus essential for reliable and profitable reactor operation. A reduction in reactor operating temperature and pressure drop with Axens’ EquiFlow® reactor internals also results in a lower CO₂ footprint associated with specific unit operation.
