A method to recover sulfur from hydrogen sulfide in an acid gas stream comprising the steps of reacting the hydrogen sulfide and oxygen in the combustion furnace, transferring heat from the furnace effluent to produce a boiler effluent, reducing the temperature of the boiler effluent in the sulfur condenser, separating the water vapor from the non-condensed gases stream, reacting the sulfur dioxide and the hydrogen gas to produce hydrogen sulfide in the first hydrogenation reactor, reacting the hydrogen sulfide and oxygen in the reactor furnace to produce a reactor effluent, transferring heat from the reactor effluent to produce a cooled effluent, reducing the temperature of the cooled effluent in the sulfur cooler to produce a gases stream, separating the water vapor from the gases stream, reacting the sulfur dioxide and the hydrogen gas to produce hydrogen sulfide in the second hydrogenation reactor to produce a treated tail gas stream.

A desulfurization system removes sulfur ingredients included in synthetic gas generated from gasification of coal in a high temperature dry state. The system includes a desulfurization reactor, a desulfurization cyclone, and first and second regeneration reactors branched with the desulfurization cyclone. A first oxidizing agent is injected to a first oxidizing agent inlet of the first regeneration reactor, and a second oxidizing agent is injected to a second oxidizing agent inlet of the second regeneration reactor. A controller operates one of the first and second regeneration reactors in a regeneration mode, controlling the other to operate in a desulfurization mode.

A desulfurization system removes sulfur ingredients included synthetic gas generated from gasification of coal in a high temperature dry state. The system includes a desulfurization reactor, a desulfurization cyclone, and first and second regeneration reactors branched in the desulfurization cyclone. A first oxidizing agent is injected to a first oxidizing agent inlet of the first regeneration reactor, and a second oxidizing agent is injected to a second oxidizing agent inlet of the second regeneration reactor. A controller operates one of the first and second regeneration reactors in a regeneration mode, controlling the other to operate in a desulfurization mode.