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 system and method including a sulfur recovery system (SRU) having a Claus system, reacting hydrogen sulfide and oxygen in a furnace to give sulfur dioxide, performing a Claus reaction in the furnace to give elemental sulfur, performing the Claus reaction in a Claus reactor to give elemental sulfur at a temperature greater than a dew point of the elemental sulfur, performing the Claus reaction in a Claus cycling reactor to give elemental sulfur at a temperature less than a solidification temperature of the elemental sulfur, depositing the elemental sulfur as solid elemental sulfur on catalyst in the Claus cycling reactor, and regenerating (heating) the Claus cycling reactor thereby forming elemental sulfur vapor from the solid elemental sulfur.

A system and method including a sulfur recovery system (SRU) having a Claus system, reacting hydrogen sulfide and oxygen in a furnace to give sulfur dioxide, performing a Claus reaction in the furnace to give elemental sulfur, performing the Claus reaction in a Claus reactor to give elemental sulfur at a temperature greater than a dew point of the elemental sulfur, performing the Claus reaction in a Claus cycling reactor to give elemental sulfur at a temperature less than a solidification temperature of the elemental sulfur, depositing the elemental sulfur as solid elemental sulfur on catalyst in the Claus cycling reactor, and regenerating (heating) the Claus cycling reactor thereby forming elemental sulfur vapor from the solid elemental sulfur.

A process and a process plant for production of elemental sulfur from a feedstock gas including from 15 vol % to 100 vol % H2S and a stream of sulfuric acid, the process including a) providing a Claus reaction furnace feed stream with a substoichiometric amount of oxygen, b) directing s to a reaction furnace operating at elevated temperature, c) cooling, d) directing to contact a material catalytically active in the Claus reaction, e) withdrawing a Claus tail gas and elemental sulfur, f) directing to a means for sulfur oxidation, g) directing to contact a material catalytically active in SO2 oxidation to SO3, h) converting to concentrated sulfuric acid, i) recycling to the Claus reaction furnace, wherein an amount of combustibles, in the Claus tail gas, is oxidized in the presence of a material catalytically active in sulfur oxidation, at an inlet temperature below 400° C.

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.

Systems and methods use bimetallic alloy particles for converting hydrogen sulfide (H.sub.2S) to hydrogen (H.sub.2) and sulfur (S), typically during multiple operations. In a first operation, metal alloy composite particles can be converted to a composite metal sulfide. In a second operation, composite metal sulfide from the first operation can be regenerated back to the metal alloy composite particle using an inert gas stream. Pure, or substantially pure, sulfur can also be generated during the second operation.

An object of the present invention is to provide a hydrogen sulfide production method enabling efficient recovery of sulfur. The production method is a method for producing hydrogen sulfide from sulfur and hydrogen comprising (1) a reaction step of reacting sulfur and hydrogen to obtain a crude hydrogen sulfide gas, (2) a purification step of purifying the crude hydrogen sulfide gas by bringing the crude hydrogen sulfide gas into contact with aliphatic lower alcohol in a packed tower to precipitate sulfur contained in the crude hydrogen sulfide gas, (3) a discharge step of discharging from inside the packed tower a suspension of sulfur in aliphatic lower alcohol obtained in the purification step, and (4) a filtration step of filtering the aliphatic lower alcohol suspension of sulfur with a filter to obtain a sulfur cake, and the filter 20 is a rotary filter 22 or a leaf filter.

Activated metal low temperature reaction processes and products are disclosed. A method for capturing a target element from a target source includes providing a matrix comprising an activated metal dispersed in a metal activating agent. The method also includes contacting the target source with the matrix. The target element is selected from the group consisting of carbon, sulfur, nitrogen, and a combination of two or more of the foregoing. The target source comprises a compound selected from the group consisting of a target carbon compound, a target sulfur compound, a target nitrogen compound, and a combination of two or more of the foregoing.

Activated metal low temperature reaction processes and products are disclosed. A method for capturing a target element from a target source includes providing a matrix comprising an activated metal dispersed in a metal activating agent. The method also includes contacting the target source with the matrix. The target element is selected from the group consisting of carbon, sulfur, nitrogen, and a combination of two or more of the foregoing. The target source comprises a compound selected from the group consisting of a target carbon compound, a target sulfur compound, a target nitrogen compound, and a combination of two or more of the foregoing.

A process for production of elemental sulfur from a feedstock gas including from 15% to 100 vol % H2S and a stream of sulfuric acid, the process including: a) providing a Claus reaction furnace feed stream substoichiometric oxygen with respect to the Claus reaction, b) directing to a reaction furnace zone operating at elevated temperature such as above 900° C., c) directing to a sulfuric acid evaporation zone downstream said reaction furnace zone, d) cooling to provide a cooled Claus converter feed gas, e) directing to contact a material catalytically active in the Claus reaction, f) withdrawing a Claus tail gas and elemental sulfur, g) directing to a Claus tail gas treatment plant, with the associated benefit of a process involving injection of sulfuric acid in a sulfuric acid evaporation zone allowing high temperature combustion of said feedstock gas, including impurities, without cooling from evaporation and decomposition of sulfuric acid.