Simulation, equipment performance evaluation and sensitivity analysis as a comprehensive parametric study of sulfur recovery unit

Abstract

The sulfur recovery unit based on modified Claus process with split flow was simulated, so that the validation results showed satisfactory agreement with the refinery data. In this study, comprehensive investigation was carried out on various parameters of the unit. Concentration changes of compounds were investigated as the process stream passes along various equipment. Composite curves were generated, and the minimum approach temperature was calculated as one of the operational parameters of heat exchangers. Fluid condensation probability was investigated in catalytic reactors. The recovery of sulfur and the amount of sulfur production were calculated by process streams passing along catalytic reactors and condensers respectively. The most influential performance parameters including the fuel flow rate, combustion air flow rate, and bypasses fraction were considered as sensitivity analysis parameters, and their variation influences were investigated on the recovery of sulfur, the ratio of hydrogen sulfide to sulfur dioxide, the amount of produced steam, and the furnace outlet stream temperature. The optimal amounts for fuel flow rate and inlet air flow rate were calculated with the values of 0 and 202 mol/s, respectively, and according to the results, 15% of the mainstream flow rate gives the optimum amount of bypass fraction.

Heat Integration in Straight‐Through Sulfur Recovery Units to Increase Net High‐Pressure Steam Production

“…The models in the process simulators consist of equations for material balance, energy balance, and reaction kinetics information of key reactions taking place in an SRU 9. These tools have been used to conduct SRU simulation studies on increasing sulfur recovery 5, 10–13, reducing natural gas consumption 14, exergy analysis 2, 15, 16, and life‐cycle analysis 17. These studies demonstrate the usefulness, popularity, and reliability of process simulation tools in simulating SRU plants that is also applied in this work.…”