Described is a control process for oxidation air management in a sulfur recovery unit. The sulfur recovery unit includes a gas feedstock inlet, an oxidation air inlet, a reaction furnace, pre-heaters, a Claus section including multiple sulfur condensers and Claus converters, and a SuperClaus section including a catalyzing SuperClaus converter, a SuperClaus sulfur condenser, and an SuperClaus oxidation air flow control valve. The control process includes analyzing one or more parameters in the sulfur recovery unit to determine a switch from the SuperClaus section to the Claus section. Additionally, conditions in the sulfur recovery unit are continuously monitored so that when a condition reaches a predetermined threshold or range, the SuperClaus oxidation air flow control valve to the SuperClaus section is opened.

A sulfur recovery unit (SRU) and method including feeding acid gas having hydrogen sulfide to a reaction furnace of the SRU, converting via the SRU the hydrogen sulfide into elemental sulfur and recovering the elemental sulfur, feeding fuel gas instead of the acid gas to the reaction furnace, adjusting flow rate of first air fed to the reaction furnace based on composition of the fuel gas, and adjusting flow rate of second air fed to the reaction furnace based on concentration of oxygen gas (O.sub.2) in furnace gas discharged from the reaction furnace.

A method for heat integration in a sulfur recovery unit, the method comprising the steps of reacting the acid gas stream and the air stream in the reaction furnace to produce a reaction effluent, where the reaction effluent comprises elemental sulfur, reducing the temperature of the reaction effluent in the heating extension to produce an effluent stream, reducing the temperature of the reaction effluent in the waste heat boiler to produce a cooled effluent stream, reducing the temperature of the cooled effluent in the sulfur condenser to produce a liquid sulfur stream and a cooled gases stream, where the liquid sulfur stream comprises the elemental sulfur, and increasing a temperature of the cooled gases stream to produce a hot gases stream, where the heating extension is configured to capture heat from the reaction effluent and release the heat to the cooled gases stream.

A method for heat integration in a sulfur recovery unit, the method comprising the steps of reacting the acid gas stream and the air stream in the reaction furnace to produce a reaction effluent, where the reaction effluent comprises elemental sulfur, reducing the temperature of the reaction effluent in the heating extension to produce an effluent stream, reducing the temperature of the reaction effluent in the waste heat boiler to produce a cooled effluent stream, reducing the temperature of the cooled effluent in the sulfur condenser to produce a liquid sulfur stream and a cooled gases stream, where the liquid sulfur stream comprises the elemental sulfur, and increasing a temperature of the cooled gases stream to produce a hot gases stream, where the heating extension is configured to capture heat from the reaction effluent and release the heat to the cooled gases stream.

Embodiments of a hydrogen sulfide destruction and sulfur recovery system of the present invention generally include a tower, sulfur introduction piping, oxygen introduction piping, and hydrogen sulfide introduction piping, wherein said tower contains a lower cooling component positioned in a vapor space of a tower bottom section, a lower vapor space fluidly connected to an upper vapor space, one or more upper and lower catalyst beds, a first condensation cooling component and a collection tray disposed in a first condensation section, a second condensation cooling component disposed in a second condensation section, a fluid pathway, partially defined by a collection tray weir, between the first condensation section and the second condensation section, a fluid pathway between a bottom section of the second condensation section and the tower bottom section, and a second condensation section bottom section gas outlet. Embodiments of a method of using the system are also provided.

A method for heat integration in a sulfur recovery unit, the method comprising the steps of reacting the acid gas stream and the air stream in the reaction furnace to produce a reaction effluent, where the reaction effluent comprises elemental sulfur, reducing the temperature of the reaction effluent in the heating extension to produce an effluent stream, reducing the temperature of the reaction effluent in the waste heat boiler to produce a cooled effluent stream, reducing the temperature of the cooled effluent in the sulfur condenser to produce a liquid sulfur stream and a cooled gases stream, where the liquid sulfur stream comprises the elemental sulfur, and increasing a temperature of the cooled gases stream to produce a hot gases stream, where the heating extension is configured to capture heat from the reaction effluent and release the heat to the cooled gases stream.

A method for heat integration in a sulfur recovery unit, the method comprising the steps of reacting the acid gas stream and the air stream in the reaction furnace to produce a reaction effluent, where the reaction effluent comprises elemental sulfur, reducing the temperature of the reaction effluent in the heating extension to produce an effluent stream, reducing the temperature of the reaction effluent in the waste heat boiler to produce a cooled effluent stream, reducing the temperature of the cooled effluent in the sulfur condenser to produce a liquid sulfur stream and a cooled gases stream, where the liquid sulfur stream comprises the elemental sulfur, and increasing a temperature of the cooled gases stream to produce a hot gases stream, where the heating extension is configured to capture heat from the reaction effluent and release the heat to the cooled gases stream.

Embodiments of a hydrogen sulfide destruction and sulfur recovery system of the present invention generally include a tower, sulfur introduction piping, oxygen introduction piping, and hydrogen sulfide introduction piping, wherein said tower contains a lower cooling component positioned in a vapor space of a tower bottom section, a lower vapor space fluidly connected to an upper vapor space, one or more upper and lower catalyst beds, a first condensation cooling component and a collection tray disposed in a first condensation section, a second condensation cooling component disposed in a second condensation section, a fluid pathway, partially defined by a collection tray weir, between the first condensation section and the second condensation section, a fluid pathway between a bottom section of the second condensation section and the tower bottom section, and a second condensation section bottom section gas outlet. Embodiments of a method of using the system are also provided.

A method for heat integration in a sulfur recovery unit, the method comprising the steps of reacting the acid gas stream and the air stream in the reaction furnace to produce a reaction effluent, where the reaction effluent comprises elemental sulfur, reducing the temperature of the reaction effluent in the heating extension to produce an effluent stream, reducing the temperature of the reaction effluent in the waste heat boiler to produce a cooled effluent stream, reducing the temperature of the cooled effluent in the sulfur condenser to produce a liquid sulfur stream and a cooled gases stream, where the liquid sulfur stream comprises the elemental sulfur, and increasing a temperature of the cooled gases stream to produce a hot gases stream, where the heating extension is configured to capture heat from the reaction effluent and release the heat to the cooled gases stream.

The present invention is directed to a process for the removal of aromatic hydrocarbons from a lean acid gas containing less than 20 mol. % of H.sub.2S, comprising: a) contacting the lean acid gas stream (1) with a H.sub.2S-selective liquid absorbent solution (29) in a first absorption zone (2) to produce a gas stream depleted in H.sub.2S (3) and an absorbent solution enriched in H.sub.2S (4), b) introducing the absorbent solution (4) into a non-thermic stripping zone (8) where it is contacted with a stripping gas stream (7) to obtain an absorbent solution depleted in C.sub.4.sup.+ aliphatic and aromatic hydrocarbons (9) and a stripping gas stream enriched in aromatic and C.sub.4.sup.+ aliphatic hydrocarbons (10), c) contacting the stripping gas stream (10) obtained in step b) with a H.sub.2S-selective liquid absorbent solution (28) in a second absorption zone (12) to obtain a stripping gas stream depleted in H.sub.2S (13), and an absorbent solution enriched in H.sub.2S (14) d) introducing the absorbent solution (9) obtained in step b) into a desorption zone (16) wherein the H.sub.2S-selective liquid absorbent solution (17) is recovered and a lean acid gas is produced.