Issue
Korean Journal of Chemical Engineering,
Vol.40, No.12, 2929-2940, 2023
Polymeric membranes for the oxygen enrichment of air in sulfur recovery units: Prevention of catalyst deactivation through BTX reduction
The modified Claus process is one of the most commonly used methods for hydrogen sulfide conversion into sulfur. However, one of the problems of this unit is the presence of benzene, toluene, and xylene (BTX) compounds at the inlet of the catalytic reactors that can deactivate the catalyst and decrease the efficiency of the sulfur recovery unit. One of the methods of BTX destruction in a furnace is to increase its temperature by increasing the oxygen concentration in the inlet air. In the present work, the application of polymeric membranes for the destruction of BTX was investigated by modeling and simulating a sulfur recovery unit and a membrane unit. The numerical results obtained from the simulations were validated successfully with industrial and experimental data for both sulfur recovery and membrane units. The simulation results for an industrial case study indicate that using five PI carbon membrane units with a total area of 26.82 m2 can increase the concentration of oxygen in the inlet air to a level of 60%. In this condition, the reduction in BTX compounds can also be increased up to 59%. Furthermore, for two-stage membrane configuration, by employing five two-stage membrane units with a total area of 58.3m2, the oxygen concentration increases to 82%, and the reduction in BTX compounds will be 75%.