| abstract |
Removal of hydrogen sulfide and oxygen in a gas enables downsizing of equipment used for concentration reduction and reduces equipment costs. In the present invention, the content of hydrogen sulfide and the content of oxygen in a syngas g, which contains hydrogen sulfide and oxygen as components to be removed or reduced in concentration, are measured using a front-stage measurement unit 13. Next, the syngas g is brought into contact with a desulfurization agent 14a comprising iron oxide. Whether to then carry out, omit or simplify oxygen removal using an oxygen removal unit 16 is selected according to measurement results from the front-stage measurement unit 13. |