Abstract: The disclosure provides seven integrated methods for the chemical sequestration of carbon dioxide (CO2), nitric oxide (NO), nitrogen dioxide (NO2) (collectively NOx, where x=1, 2) and sulfur dioxide (SO2) using closed loop technology. The methods recycle process reagents and mass balance consumable reagents that can be made using electrochemical separation of sodium chloride (NaCl) or potassium chloride (KCl). The technology applies to marine and terrestrial exhaust gas sources for CO2, NOx and SO2. The integrated technology combines compatible and green processes that capture and/or convert CO2, NOx and SO2 into compounds that enhance the environment, many with commercial value.

Abstract: The present invention refers to the field of flue gas purification, which discloses a method and apparatus for capturing carbon dioxide and producing sulfuric acid by sodium bisulfate; using a three-format electrodialysis apparatus to convert the desulfurized by-product NaHSO4 into H2SO4 while capturing CO2 in the flue gas in the cathode chamber. Under the action of electric field drive and ion exchange membrane, HSO4? enters the anode chamber to generate H2SO4 and is concentrated, and Na+ enters the cathode chamber to generate NaOH; the flue gas containing CO2 to be treated is introduced from the cathode chamber and absorbed by NaOH. The invention provides a simple, green, and economic proceeding method to capture the carbon dioxide in the flue gas during the comprehensive utilization of sodium bisulfate solution, which is of better environmental benefits and improvement of the flue gas treatment technology and reducing the pressure of desulfurization gypsum treatment.

Abstract: Systems and methods for removing hydrogen sulfide from an ammonia stream in the NH3 purification and liquefaction stage of a conventional two-column sour water stripping system using an adsorbent bed.

Abstract: Provided is a wet desulfurization process using a suspension bed. The process comprises mixing desulfurization slurry with a hydrogen sulfide containing gas to obtain a first mixture, and passing the first mixture into a suspension bed reactor from bottom to top, with controlling the first mixture to have a dwell time of 5-60 minutes in the reactor to allow they contact and react sufficiently with each other; and subjecting a second mixture obtained from the reaction to gas liquid separation to produce a purified gas. The process of the present invention may reduce the hydrogen sulfide content in the hydrogen sulfide containing gas from 2.4-140 g/Nm3 to 50 ppm or less, so that the desulfurization efficiency is 98% or more. The process of the present invention is simple and reasonable, with high desulfurization and regeneration efficiency, simple equipment, little occupation of land and low investment, which is very suitable for industrial promotion.

Abstract: A system for capturing and storing carbon dioxide. The CO2 sequestration system may include one or more sub-systems for generating electricity, a heat exchange system which may regulate temperature, and a conversion tank. The conversion tank may contain water with dissolved compounds and a catalyst. Carbon dioxide may be converted into carbonate minerals and drawn off to be used in any of a variety of applications.

Abstract: A gas clean-up unit includes a first conversion unit configured to perform a first conversion process of converting hydrogen cyanide contained in gas to be treated to ammonia, in presence of a first catalyst and at a first predetermined temperature; a second conversion unit configured to perform a second conversion process of converting carbonyl sulfide in the gas that has been subjected to the first conversion process to hydrogen sulfide, in presence of a second catalyst and at a second predetermined temperature lower than the first predetermined temperature; a cleaning unit configured to perform a cleaning process of bringing the gas into gas-liquid contact with cleaning liquid to remove the ammonia by cleaning; and a desulfurization unit configured to absorb and remove hydrogen sulfide in the gas by bringing the gas that has been subjected to the cleaning process into gas-liquid contact with absorbent.

Abstract: Provided is a renewable high efficient desulfurization process using a suspension bed, comprising mixing the desulfurization slurry with a hydrogen sulfide containing gas to obtain a first mixture, and passing the first mixture into a suspension bed reactor from bottom to top, with controlling the first mixture to have a dwell time of 5-60 minutes in the suspension bed reactor to allow they contact and react sufficiently with each other; and subjecting a second mixture obtained from the reaction to gas liquid separation to produce a rich solution and a purified gas, feeding the purified gas into a fixed bed reactor for carrying out a second desulfurization to obtain a second purified gas, subjecting the resulting rich solution to flash evaporation and then reacting with an oxygen-containing gas for carrying out regeneration. The process may reduce the sulfur content in the hydrogen sulfide containing gas from 2.

Abstract: Provided is a renewable wet desulfurization process using a suspension bed, comprising mixing the desulfurization slurry with a hydrogen sulfide containing gas to obtain a first mixture, and passing the first mixture into a suspension bed reactor from bottom to top, with controlling the first mixture to have a dwell time of 5-60 minutes in the suspension bed reactor to allow they contact and react sufficiently with each other; and subjecting a second mixture obtained from the reaction to gas liquid separation to produce a rich solution and a purified gas, subjecting the resulting rich solution to flash evaporation and then reacting with an oxygen-containing gas for carrying out regeneration. The process of the present invention may reduce the hydrogen sulfide content in the hydrogen sulfide containing gas from 2.4-140 g/Nm3 to 50 ppm or less, so that the desulfurization efficiency is 98% or more.

Abstract: Systems and methods for removing hydrogen sulfide from an ammonia stream in the NH3 purification and liquefaction stage of a conventional two-column sour water stripping system using an adsorbent bed.

Abstract: The present invention relates to methods for improving carbon capture using entrained catalytic-particles within an amine solvent. The particles are functionalized and appended with a CO2 hydration catalyst to enhance the kinetics of CO2 hydration and improve overall mass transfer of CO2 from an acid gas.

Abstract: Systems and methods for removing hydrogen sulfide from an ammonia stream in the NH3 purification and liquefaction stage of a conventional two-column sour water stripping system using an adsorbent bed.

Abstract: Systems and methods for ammonia purification in the NH3 purification and liquefaction stage of a conventional two-column sour water stripping system using an adsorbent bed.

Abstract: A method of deoxygenation of tall oil as well as methods for the production of aliphatic hydrocarbons and polymerizable monomers from tall oil. Sulphurous crude tall oil together with hydrogen gas is fed into a reactor comprising a catalyst bed. The oil is catalytically deoxygenated by hydrogen in the bed by use of a sulfided metal catalyst, e.g. a NiMoS catalyst. The flow exiting the reactor is cooled down and a hydrocarbon-bearing liquid phase is separated from a gas phase, followed by subjecting the liquid phase to distillation for removal of useless aromatic hydrocarbons and then to steam cracking to form a product containing olefins such as ethylene or propylene. By regulation of the deoxygenation temperature to be at least 270° C. but less than 360° C. the yield is rich in linear and cyclic aliphates that usefully turn to olefins in the steam cracking, while formation of napthalenes is reduced.

Abstract: Mobile treatment systems and methods for use in removing hydrogen sulfide from oilfield effluents. The systems and methods use a pre-treatment subsystem, a vapor treatment subsystem and a treatment subsystem interconnected by a plurality of piping and valve subsystems. The systems and methods are not dependent on pH and may operate at temperatures as low as ?20° C. The systems are easily transported to, and readily assembled at a site and are inexpensive, simple, quick, and extremely effective at removing large-scale quantities of hydrogen sulfide from oilfield effluents.

Abstract: A method for purifying exhaust gas of an internal combustion engine, including chemically reducing NOx that is contained in the exhaust gas when a concentration of hydrocarbons flowing into an exhaust purification catalyst is made to vibrate within a predetermined range of amplitude and within a predetermined range of period, wherein, during the chemical reduction, the NOx contained in the exhaust gas is reacted with reformed hydrocarbons to produce a reducing intermediate containing nitrogen and hydrocarbons, a reducing action of the reducing intermediate chemically reduces the NOx, and the NOx is chemically reduced without storing nitrates or with storing a fine amount of the nitrates in a basic layer of the exhaust purification catalyst.

Abstract: Methods and apparatuses are provided for producing low sulfur propane and butane. The method includes reacting a mercaptan in a washed feed stream with a caustic stream to produce a mercaptan salt in a rich caustic stream and a hydrocarbon treated stream. The mercaptan salt in the rich caustic stream is reacted with oxygen and water to produce a mixed caustic/disulfide stream, and the caustic and disulfides in the mixed caustic/disulfide stream are separated to produce a disulfide stream and the caustic stream. The hydrocarbon treated stream is fractionated to produce a propane stream, a butane stream, and a C5+ stream.

Abstract: A method for preparing magnetic iron oxide Fe21.333O32, comprising the following steps: (1) preparing a ferrous salt solution with solid soluble ferrous salt; (2) preparing a hydroxide solution; (3) mixing said hydroxide solution and said ferrous salt solution in a co-current manner for reaction at an alkali ratio of 0.6-0.8 and a reaction temperature not exceeding 30° C.; (4) after the reaction in step (3) is finished, yielding a first mixture, then charging said first mixture with a gas containing oxygen for oxidation, and controlling the first mixture at a pH value of 6-8 until the oxidation is finished to yield a second mixture; (5) filtering, washing with water and drying said second mixture obtained in step (4) to yield a precursor; and (6) calcining the precursor obtained in step (5) at 250-400° C.

Abstract: A method for preparing amorphous iron oxide hydroxide, comprising following steps: (1) preparing a ferrous salt solution with solid soluble ferrous salt; (2) preparing a hydroxide solution; (3) mixing said hydroxide solution and said ferrous salt solution in a co-current manner for reaction at an alkali ratio of 0.6˜0.8 and a reaction temperature not exceeding 30° C.; (4) after the reaction in step (3) is finished, yielding a first mixture, then charging said first mixture with a gas containing oxygen for oxidation, and controlling the first mixture at a pH value of 6˜8 until the oxidation is finished to yield a second mixture; and (5) filtering, washing with water and drying said second mixture obtained in step (4) to yield the amorphous iron oxide hydroxide.

Abstract: The present invention relates to a gas cleaning system for cleaning a gas stream containing carbon dioxide and sulfur dioxide, said gas cleaning system comprising: a pre-conditioning section (3); a CO2 removal stage (5); and a post-conditioning section (4); said pre-conditioning section comprising at least two gas-liquid contacting devices (19,20) arranged upstream of the CO2 removal stage (5) with respect to the flow direction of the gas; and said post-conditioning section comprising at least two gas-liquid contacting devices (30,31) arranged downstream of the CO2 removal stage with respect to the flow direction of the gas.

Abstract: The invention relates to an exhaust gas separating tower, comprising a washing section, a flash-distilling section above the washing section, and a liquid seal means between the flash flash-distilling section and the washing section. The washing section is configured for washing exhaust gas entering the tower with a cooling liquid to at least partially remove solid dust entrained in the exhaust gas, cool the exhaust gas, and condense at least a portion of moisture in the exhaust gas into liquid. The flash-distilling section is configured for flash-distilling the cooling liquid from the washing section to produce a cooled cooling liquid and a cooling liquid vapor. The liquid seal means is configured so that the cooling liquid produced by flash-distillation can enter the washing section through the liquid seal means while the flash-distilling section is in gas-phase isolation from the washing section, wherein a pressure in the flash-distilling section is lower than that in the washing section.

Abstract: In some embodiments, the invention provides systems and methods for removing carbon dioxide and/or additional components of waste gas streams, comprising contacting the waste gas stream with an aqueous solution, removing carbon dioxide and/or additional components from the waste gas stream, and containing the carbon dioxide and/or additional components, in one form or another, in a composition. In some embodiments, the composition is a precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, the composition further comprises carbonate and/or bicarbonate co-products resulting from co-processing SOx, NOx, particulate matter, and/or certain metals. Additional waste streams such as liquid, solid, or multiphasic waste streams may be processed as well.

Abstract: A contaminant-tolerant hybrid scrubbing solvent is provided for post-combustion CO2 capture and removal, the scrubbing solvent including an amine and a low fraction of ammonia. A stripping carrier having a low latent energy is included for solvent regeneration. In one embodiment, the amine is MEA and the stripping chemical having low latent energy is pentane or an isomer thereof. Processes and apparatus for CO2 removal from post-combustion gases and for solvent regeneration are described.

Abstract: In some embodiments, the invention provides systems and methods for removing carbon dioxide and/or additional components of waste gas streams, comprising contacting the waste gas stream with an aqueous solution, removing carbon dioxide and/or additional components from the waste gas stream, and containing the carbon dioxide and/or additional components, in one form or another, in a composition. In some embodiments, the composition is a precipitation material comprising carbonates, bicarbonates, or carbonates and bicarbonates. In some embodiments, the composition further comprises carbonate and/or bicarbonate co-products resulting from co-processing SOx, NOx, particulate matter, and/or certain metals. Additional waste streams such as liquid, solid, or multiphasic waste streams may be processed as well.

Abstract: Disclosed herein is a method comprising contacting a residual flue gas stream with a lean solution stream in an appendix stripper; where the residual flue gas stream comprises nitrogen, oxygen and moisture; and where the lean solution stream comprises ammonium, ammonium carbonate, ammonium bicarbonate and ammonium sulfate; forming a vapor phase that comprises ammonia vapor, water vapor, carbon dioxide and nitrogen; forming a liquid phase that comprises water, ammonium sulfate and ammonia; discharging the vapor phase to a capture system; and discharging the liquid phase to a direct contact cooler.

Abstract: The invention generally relates to a method for sequestration contaminates. More particularly, the invention relates to a significant performance enhancement over existing mineral carbonation processes through the use of a high mass transfer system and an efficient pH swing reaction. More particularly, aspects of the invention are directed to direct and indirect methods of sequestering contaminates.

Abstract: A flue-gas purification system includes a flue-gas cycling system, a reactor, and an absorbent adding system having at least a catalytic absorbent, wherein the catalytic absorbent is being gasified for reacting with the flue-gas in the reactor in a homogenous gas-gas phase reacting manner. Therefore, the purification system has fast reaction rate between the pollutants of the flue-gas and the catalytic absorbent, which is preferably ammonia, to efficiently remove pollutants, so as to effectively purify the flue-gas.

Abstract: A system and a process for capture and absorption of sulfur dioxide and carbon dioxide by an ammonia method at normal pressure are disclosed.

Abstract: A process for manufacturing a catalyst composition includes the steps of (i) combining one or more soluble metal compounds with a solution of an alkaline metal carbonate precipitant to form a precipitate of insoluble metal carbonates, (ii) processing the insoluble metal carbonates into a catalyst or catalyst precursor with the evolution of carbon dioxide, (iii) recovering at least a portion of the evolved carbon dioxide, and (iv) reacting the recovered carbon dioxide with a suitable alkaline metal compound in an absorber column to generate an alkaline metal carbonate, wherein at least a portion of the generated alkaline metal carbonate is used as a precipitant in step (i).

Abstract: Systems are described for dissolving metal silicates to: produce metal hydroxide; remove carbon dioxide or other acid gases from the atmosphere or other gas mixture by reacting such gases with the metal hydroxide; penetrate or excavate metal silicates; extract metals or silicon-containing compounds from metal silicates; and produce hydrogen and oxygen or other gases.

Abstract: Devices and methods for reacting carbon dioxide with ammonia to produce an ammonium bicarbonate containing product are disclosed. Further disclosed are methods and devices pertaining to the handling of ammonia, ammonium bicarbonate products, and waste products associated with that production.

Abstract: The invention relates to a method of removing carbon dioxide from a process gas, the method comprising: a) allowing an ammoniated solution to enter an absorption arrangement, said absorption arrangement comprising at least a first absorber; b) contacting the ammoniated solution with the process gas in said first absorber, the ammoniated solution capturing at least a part of the carbon dioxide of the process gas; c) allowing the ammoniated solution to exit the absorption arrangement; d) cooling the ammoniated solution, wherein at least a part of the captured carbon dioxide is precipitated as solid salt; e) allowing the cooled ammoniated solution to enter a separator, in which separator at least a part of the precipitated solids are removed from the ammoniated solution, after which the ammoniated solution is allowed to exit the separator; f) heating the ammoniated solution; and g) allowing the heated ammoniated solution to re-enter the absorption arrangement.

Abstract: A system for removing carbon dioxide from a flue gas stream is provided, the system comprising an absorber vessel configured to receive a flue gas stream, the absorber vessel comprising a first absorption stage configured to receive the flue gas stream and contact it with a first ionic solution, a second absorption stage configured to receive flue gas which has passed the first absorption stage and contact it with a second ionic solution, a first sump vessel, and a second sump vessel.

Abstract: The present invention relates to a method and system for cleaning a process gas containing carbon dioxide and contaminants, by bringing the process gas into direct contact with an alkaline solution or slurry, and capturing in the alkaline solution or slurry at least a part of the contaminants of the process gas; and bringing the process gas, depleted in contaminants, into direct contact with a cooling liquid to form a cooled process gas; wherein said alkaline solution or slurry is separate from the cooling liquid.

Abstract: Conventionally air filters are particulate filters composed of fibrous materials in order to remove solid particulates such as dust, pollen, mold, and bacteria from the air. Accordingly, it would be beneficial to provide absorbent filters within such systems in order to address the removal of gaseous impurity components from the circulating air in addition to conventional particulate tillers. It would be further beneficial to provide such absorbent filters in a manner which is compatible with commercial and residential environments that represent the majority of such air circulation systems. It would be further beneficial to provide such absorbent filters in formats that are compatible with new system installations as well as retrofitting to existing system installations.

Abstract: Aspects of the disclosure relate to the separation of gases and to a process for the removal of carbon dioxide gas using liquid absorbents. A process is disclosed for removing carbon dioxide from a gaseous stream comprising contacting the gaseous stream with a carbon dioxide absorbent comprising a mixture of an ionic liquid and water in a molar ratio of from 10:1 to 1:10, wherein the ionic liquid has the formula: [Cat+][X?].

Abstract: The present invention describes methods and systems for extracting, capturing, reducing, storing, sequestering, or disposing of carbon dioxide (CO2), particularly from the air. The CO2 extraction methods and systems involve the use of chemical processes. Methods are also described for extracting and/or capturing CO2 via exposing air containing carbon dioxide to a solution comprising a base—resulting in a basic solution which absorbs carbon dioxide and produces a carbonate solution. The solution is causticized and the temperature is increased to release carbon dioxide, followed by hydration of solid components to regenerate the base.

Abstract: In a method of producing carbonate mineral, a first aqueous solution containing an alkaline earth metal ion extracted from a cation exchange medium by a cation exchange reaction and carbon dioxide are added to a second aqueous solution to form a carbonate mineral.

Abstract: A method for the reduction of corrosion in a treatment unit acid used for separating hydrogen sulfide from and acid gas stream using an alkaline absorption solution. Ions comprising the S2? and/or HS? ions formed by the absorption of the hydrogen sulfide in the absorbent solution are subjected to in situ electrochemical oxidization to form polysulfide ions which form a protective coating on the surfaces of the unit.

Abstract: A system is arranged to remove carbon dioxide (CO2) from a gas stream by bringing the gas stream into contact with a circulating ammoniated solution stream such that CO2 is removed from the gas stream by the ammoniated solution stream. A method of removing non-volatile compounds from the circulating ammoniated solution stream includes: introducing a portion of the circulating ammoniated solution stream into a gas-liquid separating device; and separating the introduced ammoniated solution into an ammonia rich gas phase and a liquid phase comprising the non-volatile compounds; and reintroducing the ammonia rich gas phase into the circulating ammoniated solution stream.

Abstract: A process for removing CO2 from a CO2 containing gas stream in which the CO2 containing gas stream is contacted with an aqueous ammonium solution. The aqueous ammonia solution comprises 0.1-40% w/v, v/v/w/w ammonia, and a soluble salt at a concentration range of 0.01%-10% wt or v/v or w/v, the soluble salt having cations selected from the group of group IA, IIA, IIIA and IVA metals with counter anions selected from the group of anion of group VIIA elements, NO3?, SO42?, OH?, PO43? and HCO3?. The invention also extends to a CO2 capture solvent comprising an aqueous ammonia solution and the above soluble salt.

Abstract: An apparatus and method for removing contaminants from a gas stream is provided which includes (a) introducing the gas stream into a reaction chamber of a scrubber; (b) oxidizing first contaminants in a liquid phase with a reactive species in a sump of the scrubber for providing an oxidizing solution; (c) oxidizing second contaminants in a gas phase of the gas stream above the sump with excess reactive species disengaging from the oxidizing solution in the sump; (d) oxidizing and scrubbing third contaminants in a gas-liquid contact assembly disposed above the gas stream.

Abstract: A system and a method is provided for removing carbon dioxide from a gas stream. One aspect of the method includes introducing a carbon dioxide-containing gas stream to an absorber. The gas stream is contacted with an ammonia-containing solvent for absorbing, with the ammonia-containing solvent, the carbon dioxide from the gas stream, thereby removing the carbon dioxide from the gas stream.

Abstract: A flue-gas purification system includes a flue-gas cycling system, a reactor, and an absorbent adding system having at least a catalytic absorbent, wherein the catalytic absorbent is being gasified for reacting with the flue-gas in the reactor in a homogenous gas-gas phase reacting manner. Therefore, the purification system has fast reaction rate between the pollutants of the flue-gas and the catalytic absorbent, which is preferably ammonia, to efficiently remove pollutants, so as to effectively purify the flue-gas.

Abstract: Methods and systems for producing hydrogen and capturing carbon dioxide are disclosed. In some embodiments, the methods include the following: mixing magnesium bearing minerals with one or more acids and/or chelating agents to form a magnesium-rich solvent including magnesium hydroxide; mixing a gas including carbon dioxide with the magnesium-rich solvent in a reactor possibly in the presence of one or more water-gas shift catalysts; increasing a temperature and a steam pressure inside the reactor until a substantial portion of the magnesium hydroxide in the solvent and the carbon dioxide and water in the gas react to form magnesium carbonate and hydrogen; and increasing pH in the reactor thereby increasing a rate that the solvent and the carbon dioxide react.

Abstract: A carbon dioxide sequestration process includes the following steps. In a first stage, a slurry of a metal silicate rock is mixed with ammonia so as to produce a ammonia/water/metal silicate slurry. In a second stage, the process includes scrubbing a gas stream containing carbon dioxide with the solution from the first stage to thereby absorb the carbon dioxide into a reactive slurry. In a third stage, the reactive slurry from the second stage is passed through a reactor that is controlled so as to promote the reaction between the carbon dioxide and the metal silicate to thereby produce a metal carbonate.

Abstract: A process of CO2 removal from a flue gas, comprising: (a) contacting a flue gas with a CO2 lean ammonia-comprising medium to produce a CO2 rich ammonia-comprising medium; (b) heating the CO2 rich ammonia-comprising medium to produce a regenerated CO2 lean ammonia-comprising medium; and (c) supplying the regenerated CO2 lean ammonia-comprising medium to said absorber; (d) identifying a desired mole ratio of ammonia to CO2 of the CO2 lean ammonia-comprising medium; (e) predicting a desired temperature of regenerated CO2 lean ammonia-comprising medium present in a sump of a regeneration vessel or predicting a desired operating pressure of a regeneration vessel; (f) controlling the temperature of regenerated CO2 lean ammonia-comprising medium present in the sump of the regeneration vessel or the operating pressure of the regeneration vessel. A system for removal of CO2 from a flue gas, comprising: i.a. a control unit.

Abstract: The present invention provides a method and apparatus for the treatment of process gas from an anaerobic digestion system or a landfill gas system. In one embodiment, the system comprises a caustic scrubber including a vertical column having a top and a bottom and including a counter current flow system, wherein a process gas stream flows up vertically through the column in counter current flow to a caustic liquid solution that flows downward through the column. The caustic liquid solution removes at least one acid from the process gas stream, wherein treated gas that is substantially free of acids bubbles out through an opening at the top of the vertical column.

Abstract: The invention relates to a method adapted for integration with a carbonate absorption/stripping process for removal of carbon dioxide, the method and system including the steps of: converting a source of alkali from a first industry to a non-carbonate alkali; feeding the non-carbonate alkali as makeup to a carbonate absorption system for stripping carbon dioxide from emissions from a second industry; recovering an output from the system for stripping carbon dioxide, and in the process of conversion of the alkali from the first industry, utilising energy from the second industry.

Abstract: The present invention consists of an absorption process with a chemical reaction to capture acid gases such as carbon dioxide, sulphur dioxide and nitrogen dioxide from the ambient air and from combustion gases from burners and internal combustion engines using fossil fuels; the aim of the invention being the acquisition of carbon credits in accordance with the “Kyoto protocol on climate change”. The process is carried out in a horizontal spray absorber using an 8% solution of sodium hydroxide as absorption liquid, obtaining sodium carbonate, sodium sulphite, sodium nitrite and nitrate as byproducts. These byproducts are converted into commercial products such as calcium carbonate, barium sulphate and ammonium nitrate; for which purpose both the sodium sulphite and the sodium nitrite must previously be converted into sodium sulphate and nitrate by means of an oxidizing agent.

Abstract: The present invention provides a biological H2S removal system for the treatment of process gas, comprising: a housing that receives a process gas stream through a gas inlet, the housing comprising a plurality of layers through which the process gas stream flows while it is treated for H2S removal, and a gas outlet through which a treated gas stream exits; wherein air is added to the process gas stream prior to the process gas stream entering the housing.