The invention is directed to a continuous process to treat a hydrogen sulphide comprising gas comprising the following steps: (a) contacting the hydrogen sulphide comprising gas with an aqueous alkaline solution further comprising sulphide oxidising bacteria thereby obtaining a loaded aqueous solution comprising sulphide compounds and sulphide oxidising bacteria. (b) contacting the loaded aqueous solution with an oxygen comprising gas to regenerate the sulphide oxidising bacteria to obtain a liquid effluent comprising regenerated sulphide oxidising bacteria which is partly used as the aqueous alkaline solution in step (a). (c) separating elemental sulphur as prepared by the sulphide oxidising bacteria in steps (a) and (b) from the loaded aqueous solution of step (a) and/or from the liquid effluent of step (b) and wherein the consumption of oxygen in step (b) is measured and wherein the supply of oxygen in step (b) is controlled by the measured consumption of oxygen.

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 for the removal of hydrogen sulfide and sulfur recovery from a H.sub.2S-containing gas stream by catalytic direct oxidation and Claus reaction through two or more serially connected catalytic reactors, wherein a specific control of the oxygen supplement is operated. The control and improvement of the process is obtained by complementing, in each major step of the process, the H.sub.2S-containing gas stream by a suitable flow of oxygen, namely before the H.sub.2S-containing gas stream enters the Claus furnace, in the first reactor of the process and in the last reactor of the process. Especially in application in a SubDewPoint sulfur recovery process the H.sub.2S/SO.sub.2 ratio is kept constant also during switch-over of the reactors R1 and R by adding the last auxiliary oxygen containing gas directly upstream the last reactor R so that the H.sub.2S/SO.sub.2 ratio can follow the signal of the ADA within a few seconds.

The invention relates to a cyclic method for capturing and utilizing CO.sub.2 contained in a gas stream. The method uses three different materials, a first solid material, a second solid material and a CO.sub.2 sorbent material.

In a first step a first gas stream comprising CO.sub.2 and at least one reductant is brought in contact with the three materials, resulting in an outlet stream comprising water. In a second step, the captured CO.sub.2 from the first step is released and converted to CO to produce a CO rich outlet stream. The invention further relates to an installation for capturing and utilizing CO.sub.2.

A method of optimising operating conditions in an abatement apparatus configured to treat an effluent stream from a processing tool and an abatement apparatus are disclosed. The method of optimising operating conditions in an abatement apparatus configured to treat an effluent stream containing PFC from a processing tool comprise: changing an operating parameter which controls an operating condition of the abatement apparatus; determining a change in a PFC concentration present in an exhaust stream of the abatement apparatus; and determining whether to retain the operating parameter based on the change in the PFC concentration. In this way, the concentration of PFC present in the exhaust can be used to determine whether the abatement apparatus is operating under the correct operating conditions or not.

An efficient ammonia desulphurization and oxidation apparatus includes a desulphurization tower, where spray layers in multiple stages and a tower reactor are sequentially arranged in the desulphurization tower; a first gas-liquid distribution plate, a second gas-liquid distribution plate, and a third gas-liquid distribution plate are sequentially arranged in the tower reactor; an ammonia distribution zone is formed between the first and second gas-liquid distribution plates, and an ammonia water distributor is further arranged between the first gas-liquid distribution plate and the second gas-liquid distribution plate in the ammonia distribution zone; an absorption zone is formed between the second and third gas-liquid distribution plates; an oxidation zone is formed between the third gas-liquid distribution plate and a bottom of the tower; in the oxidation zone, oxidizing air distributors in multiple stages are arranged at a lower side of the third gas-liquid plate.

A membrane module includes a housing. The housing includes a housing, comprising: a first plurality of porous hollow fiber membranes, and a second plurality of porous hollow fiber membranes different from the first plurality of porous hollow fiber membranes. The first plurality of porous hollow fiber membranes has a first length, and the second plurality of porous hollow fiber membranes has a second length that is at least 1.1 times greater than the first length. The membrane module can be used in separation methods, such as membrane distillation methods.

Apparatus and methods are disclosed. The apparatus comprises: an abatement chamber of an abatement apparatus which treats an effluent stream from a semiconductor processing tool to provide a combusted effluent stream having effluent particles; and a first atomiser located downstream of the abatement chamber, the first atomiser being configured to produce droplets having a droplet size based on a particle size of the effluent particles to be removed from the combusted effluent stream. In this way, the atomizer may produce droplets which combine with or adhere to the effluent particles which assists in the removal of the effluent particles from the combusted effluent stream.

A gas treatment method includes: a process (a) of allowing gas to be treated in which a target substance to be treated is mixed with air to pass through inside a housing, the target substance to be treated exhibiting volatility at room temperature and belonging to at least one substance selected from a group consisting of carbon compounds, nitrogen compounds, and sulfur compounds; a process (b) of introducing ozone into a space through which the gas to be treated flows inside the housing at 200° C. or lower; a process (c) of stirring the gas to be treated after the process (b); and a process (d) of heating the gas to be treated to 300° C. or higher after executing the process (c).

Processes for reducing carbon monoxide levels in a carbon dioxide rich gaseous stream. The carbon dioxide rich stream is passed to a preferential oxidation zone to selectively convert carbon monoxide to carbon dioxide. Excess oxygen is consumed by reacting with hydrogen, which may be added or controlled based on PSA operating conditions upstream of the preferential oxidation zone. The preferential oxidation zone may be contained within a bed of a dryer.