Described is a process for treatment of a fluid comprising an oxidizable contaminant selected from one or both of a sulfide and a thiol, the process comprising the step of contacting the fluid with a first complex of ferric iron and a polyphosphate to oxidize the oxidizable contaminant and generate a second complex of ferrous ion and the polyphosphate.

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 method of producing sulphuric acid from a sour tail gas comprises (a) obtaining a sour tail gas stream comprising H.sub.2S or reduced sulphur species or a combination thereof from an oil and gas facility; (b) subjecting the sour tail gas stream to oxidation and obtaining an oxidized gas stream comprising SO.sub.2; and, (c) utilizing the oxidized gas stream to obtain sulphuric acid and a SO.sub.2 reduced tail gas stream. The method may further comprise subjecting the oxidized gas stream to a regenerable absorption process. The sulphuric acid may be used to produce fertilizer.

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.

A process and method for removing hydrogen sulfide from a gas and regenerating ferric ions consumed in the hydrogen sulfide scrubbing process at low pH. A two-scrubber regenerative chemical scrubbing system for removing hydrogen sulfide from a gas that provides an economical system for removing hydrogen sulfide from a gas at low pH without the need for chelating agents. An oxide of manganese is used as a catalyst to enhance the regeneration of ferric ions in an aqueous solution under acidic conditions in the presence of oxygen. The process may further include contacting the aqueous solution with a second gas comprising air to replenish the dissolved oxygen in the aqueous solution. The regenerated solution comprising ferric ions can be reused to treat additional hydrogen sulfide containing gases.

A method for cleaning an off-gas from viscose production, essentially containing H.sub.2S and CS.sub.2, comprises passing the gas through a catalytic reactor containing a direct oxidation type catalyst, such as V.sub.2O.sub.5 on silica, to convert H.sub.2S in the gas to elemental sulfur, SO.sub.2 or mixtures thereof, either via the oxygen present in the gas or via oxygen added to the gas stream. Elemental sulfur and SO.sub.2 are removed from the effluent gas from the catalytic reactor, and the unconverted CS.sub.2 is recycled to the viscose production process.

An electrochemical process is provided for producing hydrogen for use in a hydrotreatment process. Hydrogen sulfide and ammonia that are produced during the hydrotreatment process are subjected to electrolysis using electrolysis cells and select catalysts to produce hydrogen which then can be used in the hydrotreatment process instead of using outside sources of hydrogen.

A method of generating electricity in a body of water includes providing a colony of sulfur-reducing bacteria, a colony of sulfur-oxidizing bacteria, and a colony of denitrifying bacteria submerged in the body of water. The colony of sulfur-reducing bacteria can be used to convert at least a portion of sulfates present in the body of water to hydrogen sulfide. The colony of sulfur-oxidizing bacteria can be used to convert the hydrogen sulfide to sulfuric acid, which can react with manganese to produce hydrogen gas. The colony of denitrifying bacteria can be used to convert at least a portion of nitrogen oxides in the body of water to nitrogen gas, which can be bubbled through a portion of water from the body of water to remove dissolved oxygen gas. The hydrogen gas and oxygen gas can be combined in a fuel cell generator to generate electricity.