Besides improved catalyst systems, what advances in reactor internals are improving efficiency and throughput while also mitigating the effect of fouling and catalyst poisons?

First published in PTQ Catalysis 2023

Dinesh-Kumar Khosla, Global Market Manager Heavy Ends, HDC, Axens

Finding the right combination of catalyst and reactor internals is essential for reliable and profitable reactor operation. In units featuring fixed-bed reactors, along with optimum catalyst design, overall reactor/catalyst performance can be enhanced by using high-efficiency reactor internals.

Axens’ proprietary EquiFlow reactor internals ensure a uniform gas/liquid distribution and optimum mixing in the reactor, thereby minimizing channeling and hot spots to ensure optimal use of the entire catalyst inventory in the reactor. This enhances catalyst activity, selectivity, and stability, and minimizes catalyst changeout frequency while ensuring safe and reliable operation.
EquiFlow distributor trays employ a dispersive system located below a chimney tray to ensure close-to-ideal vapor/liquid distribution throughout the catalytic bed underneath.
Axens EquiFlow quench systems (Hy-Quench-XM, 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, resulting in longer catalyst cycles and/or higher throughput operation.

To mitigate the effect of fouling, the EquiFlow smart filtering tray system (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. Reduction in reactor operating temperature and pressure drop with Axens’ EquiFlow reactor internals also result in lower CO2 footprint associated with specific unit operation.