Provided herein are methods and systems for treating a tail gas of a Claus process to remove sulfur-containing compounds. The method includes combusting a tail gas of a Claus process in an excess of oxygen gas to yield a thermal oxidizer effluent. The thermal oxidizer effluent includes sulfur dioxide, water vapor, and oxygen. The effluent is routed to a quench tower and contacted with a dilute aqueous acid quench stream to yield sulfurous acid, hydrated sulfur dioxide, or both. The sulfurous acid or hydrated sulfur dioxide is oxidized with the excess oxygen from the thermal oxidizer effluent to yield sulfuric acid.

A process plant and a process for production of sulfur from a feedstock gas including from 15% to 100 vol % H.sub.2S 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 to a Claus reaction furnace operating at elevated temperature, c) cooling to provide a cooled Claus converter feed gas, d) directing to contact a material catalytically active in the Claus reaction, e) withdrawing a Claus tail gas and elementary sulfur, f) directing a stream comprising said Claus tail gas to a Claus tail gas treatment, wherein sulfuric acid directed to said Claus reaction furnace is in the form of droplets with 90% of the mass of the droplets having a diameter below 500 μm, with the associated benefit of such a process efficiently converting all liquid H.sub.2SO.sub.4 to gaseous H.sub.2SO.sub.4 and further to SO.sub.2.

A revamp process for modifying a sulfur abatement plant including a Claus process plant, the Claus process plant including a Claus reaction furnace and one or more Claus conversion stages, each Claus conversion stage including a conversion reactor and a means for elemental sulfur condensation, and a means of Claus tail gas oxidation configured for receiving a Claus tail gas from said Claus process plant and configured for providing an oxidized Claus tail gas, the process revamp including: a) providing a sulfuric acid producing tail gas treatment plant producing sulfuric acid, and b) providing a means for transferring an amount or all of the sulfuric acid produced in said sulfuric acid producing tail gas treatment plant to said Claus reaction furnace, wherein the moles of sulfur in the transferred sulfuric acid relative to the moles of elemental sulfur withdrawn from the Claus process plant is from 3% to 25%.

This invention relates to a system and method for improving sulfur recovery from a Claus unit. More specifically, this invention provides a steam swept membrane tail gas treatment system and method for treating acid gas streams and minimizing sulfur dioxide emissions therefrom.

A method for sulfur recovery includes, in a hydrogenation reactor, converting sulfur-containing compounds in a Claus tail gas stream to hydrogen sulfide to produce a hydrogenated gas stream; feeding the hydrogenated gas stream to a quench tower to produce a quenched gas stream by condensing liquid water; feeding the quenched gas stream to a first stage adsorption vessel of a first stage adsorption unit to produce a first outlet gas stream by adsorbing water from the quenched gas stream; feeding the first outlet gas stream to a second stage adsorption vessel of a second stage adsorption unit to produce a second byproduct gas stream by adsorbing hydrogen sulfide from the first outlet gas stream; separating the second byproduct gas stream into a carbon dioxide stream and an enriched nitrogen stream; and regenerating the second stage adsorption vessel using the enriched nitrogen stream.

A catalyst for selectively oxidizing hydrogen sulfide to element sulfur, catalyst for burning tail-gas, and process for deeply catalytically oxidizing hydrogen sulfide to sulfur are disclosed. The catalyst for selectively oxidizing hydrogen sulfide to element sulfur is prepared by: 10-34% of iron trioxide and 60-84% of anatase titanium dioxide, and the balance being are auxiliary agents. Also a catalyst for burning tail-gas is prepared by: 48-78% of iron trioxide and 18-48% of anatase titanium dioxide, and the balance being auxiliary agents. The catalyst of the present invention has high selectivity and high sulfur recovery rate. An isothermal reactor and an adiabatic reactor of the present invention are connected in series and are filled with the above two catalysts for reactions, thus reducing total sulfur in the vented gas while having a high sulfur yield and conversion rate.

An elemental sulfur recovery unit comprising a thermal unit configured to combust an acid gas feed comprising hydrogen sulfide, an oxygen source, and a fuel gas to create a reaction furnace outlet stream, comprising elemental sulfur, a waste heat boiler configured to capture heat from the reaction furnace outlet stream to create a waste heat boiler effluent, a condenser configured to condense the waste heat boiler effluent to produce a non-condensed gases stream and a condensed stream comprising elemental sulfur, a process gas reheater configured to generate a hot gases stream, a hydrogenation reactor configured to convert the hot gases stream to create a hydrogenation effluent comprising hydrogen sulfide, a process desuperheater configured to cool the hydrogenation effluent to generate a cooled effluent, and an absorber unit configured to absorb the hydrogen sulfide from the cooled effluent to produce a hydrogen sulfide recycle stream and a waste gas stream.

The invention concerns a method for treating a hydrocarbon feed gas stream containing at least CO.sub.2 and H.sub.2S to recover a high quality purified CO.sub.2 gas stream, comprising a. Separating said hydrocarbon feed gas stream into a sweetened hydrocarbon gas stream, and an acid gas stream; b. Introducing said gas stream into a Claus unit, c. Introducing the tail gas into a hydrogenation reactor and then into a quench contactor of the Tail Gas Treatment Unit (TGTU); d. Contacting said tail gas stream with a non-selective amine-based solvent into a non-selective acid gas absorption unit of the TGTU; e. Sending the off gas to an incinerator; f. Contacting said enriched gas stream (vii) with a selective H.sub.2S-absorption solvent into a selective H.sub.2S-absorption unit thereby recovering a highly purified CO.sub.2 gas stream and a H.sub.2S-enriched gas stream, as well as the device for carrying said method.

A vertically oriented sulfur condenser may employ a plurality of condenser tubes arranged longitudinally within an exterior casing, a liquid sulfur reservoir at a longitudinal end of the sulfur condenser, and a condenser tube wall of at least one of the plurality of condenser tubes that protrudes into and below a liquid sulfur reservoir. A catalyst may be located within the liquid sulfur reservoir. A liquid sulfur outlet may be located at the liquid sulfur surface. A Claus process gas inlet may be proximate a first end of the plurality of condenser tubes. A first tube sheet may connect to and seal an end of the plurality of condenser tubes proximate a first end of the plurality of condenser tubes. A second tube sheet may connect to and seals with the plurality of condenser tubes and the exterior casing proximate a second end of the plurality of condenser tubes.

A process of producing degassed liquid sulfur using process gas containing H.sub.2S to agitate the liquid sulfur being degassed while in contact with a degassing catalyst. Process gas is less costly and less complicated and quickly accomplishes substantial degassing rendering the liquid sulfur much safer in storage and transportation.