Kinetic Simulations of H2 Production from H2S Pyrolysis in Sulfur Recovery Units Using a Detailed Reaction Mechanism

Abstract

Acid gas (H2S and CO2) is produced in large volumes worldwide from the desulfurization of hydrocarbon fuels and is utilized in sulfur recovery units (SRUs) to produce sulfur. However, the hydrogen content of acid gas is wasted as low-grade steam, which highlights the need for the efficient utilization of this resource. The production of H2 from acid gas is desired, as it is an inexpensive feedstock. In this work, a kinetic study is conducted on H2 production from acid gas in an industrial SRU to utilize its built-in inertia, while saving on the capital cost and enhancing the processing capacity of the SRU. The thermal energy generated during the combustion of acid gas in the reaction furnace (RF) is used for acid gas pyrolysis in the waste heat boiler (WHB) of the SRU. While this technique has been investigated previously, its realization at the industrial scale is hindered by low H2 yield. This paper presents suitable means of enhancing H2 production via operational modifications in RF and WHB. A detaile...