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.

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?, OH43?, PO43? and HCO3?. The invention also extends to a CO2 capture solvent comprising an aqueous ammonia solution and the above soluble salt.

Abstract: A hydrometallurgical process for a nickel oxide ore comprising obtaining an aqueous solution of crude nickel sulfate by high pressure acid leaching of a nickel oxide ore; obtaining a zinc free final solution by sulfurization of the solution; obtaining a waste solution; and scrubbing hydrogen sulfide gas from an exhaust gas. The process is characterized by at least one of the following operations: Adjusting the total volume (m3) of a sulfurization reactor to a ratio of 0.2-0.9 (m3/kg/h) relative to the input mass (kg/h) of the nickel to be introduced to the reactor; and/or subjecting the waste solution and the exhaust gas to countercurrent contact, then introducing the exhaust gas back to the scrubber and charging the waste solution from the scrubber into the sulfurization reactor.

Abstract: Methods of sequestering carbon dioxide (CO2) are provided. Aspects of the methods include precipitating a storage stable carbon dioxide sequestering product from an alkaline-earth-metal-containing water and then disposing of the product, e.g., by placing the product in a disposal location or using the product as a component of a manufactured composition. Also provided are systems for practicing methods of the invention.

Abstract: An improved process for deacidizing a gaseous mixture using phase enhanced gas-liquid absorption is described. The process utilizes a multiphasic absorbent that absorbs an acid gas at increased rate and leads to reduced overall energy costs for the deacidizing operation.

Abstract: Provided are methods for sequestering carbon dioxide utilizing magnesium hydroxide. A recovery method and system for recovering a gaseous component is provided. Methods and systems may utilize an alkaline component produced by thermal activation of magnesium hydroxide. Compositions of sequestered carbon dioxide comprising magnesium carbonate or magnesium bicarbonate are provided.

Abstract: Disclosed is a method of removing carbon dioxide from a process gas, the method comprising: contacting an ammoniated solution with the process gas in an absorption arrangement 101, the ammoniated solution capturing at least a part of the carbon dioxide of the process gas, wherein the molar ratio, R, of ammonia to carbon dioxide in the ammoniated solution is controlled such that substantially no precipitation of solids occurs within the absorption arrangement 101; allowing ammoniated solution including captured carbon dioxide to exit the absorption arrangement 101; cooling the ammoniated solution that has exited the absorption arrangement, wherein at least a part of the captured carbon dioxide is precipitated as solid salt; separating at least a part of the precipitated salt from the ammoniated solution; heating the ammoniated solution from which the at least a part of the precipitated salt has been separated, such that substantially no solids are present in the heated ammoniated solution; and allowing the hea

Abstract: Ultra cleaning of combustion gas to near zero concentration of residual contaminants followed by the capture of CO2 is provided. The high removal efficiency of residual contaminants is accomplished by direct contact cooling and scrubbing of the gas with cold water. The temperature of the combustion gas is reduced to 0-20 degrees Celsius to achieve maximum condensation and gas cleaning effect. The CO2 is captured from the cooled and clean flue gas in a CO2 absorber utilizing an ammoniated solution or slurry in the NH3—CO2—H2O system. The absorber operates at 0-20 degrees Celsius. Regeneration is accomplished by elevating the pressure and temperature of the CO2-rich solution from the absorber. The CO2 vapor pressure is high and a pressurized CO2 stream, with low concentration of NH3 and water vapor is generated. The high pressure CO2 stream is cooled and washed to recover the ammonia and moisture from the gas.

Abstract: A method of heating a used absorption liquid resulting from a carbon dioxide absorption stage in which a CO2 comprising gas stream is contacted with an absorption liquid comprising ammonia, wherein the used absorption liquid is subjected to heat exchange, in a heat exchanger, with a fluid of a desulfurization stage in which a SO2 comprising flue gas is contacted with a reagent composition comprising an alkaline compound.

Abstract: The present invention relates to a method for preparing ammonium bicarbonate with flue gas and device thereof. The method includes quantitatively collecting flue gas with a carbon dioxide concentration of about 8% to about 15% (volume), decreasing the temperature of the flue gas to about 50° C. or less with an air-cooling apparatus, then increasing the pressure of the flue gas to about 0.4 to about 1.2 MPa, and finally allowing the flue gas to react with liquid ammonia to produce ammonium bicarbonate. The device for preparing ammonium bicarbonate with flue gas includes a flue gas collecting apparatus, an air-cooling apparatus, a gas storing and pressurizing apparatus and an ammonium bicarbonate synthesizing apparatus. The issue of energy consumption brought by conventional cooling approach using cooling water is addressed by using an air-cooling apparatus.

Abstract: The present invention provides a method and apparatus for sequestering carbon from atmospheric air using a hydroxide compound in a two stage process to maximize carbon dioxide capture. The first stage is provided by a coarse filter saturated with a calcium hydroxide solution. The second stage is provided by a reaction chamber having at least one spray nozzle for creating a mist of hydroxide solution within the reaction chamber. Air is drawn through the device by a fan to cause the air to first contact the hydroxide solution on the saturated filter, and then to contact the hydroxide solution in the mist sprayed within the reaction chamber. The hydroxide solution is collected in a reservoir, centrifuged to separate the captured carbon from the solution, and then recirculated back into the saturated filter and through the spray nozzles into the reaction chamber.

Abstract: Provided is a fixation method of carbon dioxide. The method includes a) grinding waste gypsum to become 200˜300 mesh; b) performing reaction by supplying mixed gas while mixing the ground waste gypsum with aqueous ammonia, and c) separating solid from liquid in the manufactured slurry by centrifugation and drying separated solid and liquid portions with calcite and ammonium sulfate, wherein the mixed gas is formed of nitrogen and carbon dioxide, and the carbon dioxide provides carbon dioxide fixation method containing 5˜25 wt %. When carbon dioxide is fixed by using waste gypsum, reaction efficiency is remarkably high. The fixation method makes more than 95% of supplied carbon dioxide fixed. Also, provided is an economical method that disposes carbon dioxide as a disposal target without its separation, refinement and liquefaction processes, to thereby remarkably reduce the entire process and costs for processes.

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: According to an exemplary aspect of the invention a method of sorption of CO2 out of flue gas is provided, wherein the method comprises contacting the flue gas and an ionic liquid comprising an anion and a non-aromatic cation.

Abstract: A system for forming metal hydroxide from a metal carbonate utilizes a water electrolysis cell having an acid-producing anode and a hydroxyl-producing cathode immersed in a water solution of sufficient ionic content to allow an electric current to pass between the hydroxyl-producing cathode and the acid-producing anode. A metal carbonate is placed in close proximity to the acid-producing anode. A direct current electrical voltage is provided across the acid-producing anode and the hydroxyl-producing cathode sufficient to generate acid at the acid-producing anode and hydroxyl ions at the hydroxyl-producing cathode. The acid dissolves at least part of the metal carbonate into metal and carbonate ions allowing the metal ions to travel toward the hydroxyl-producing cathode and to combine with the hydroxyl ions to form the metal hydroxide. The carbonate ions travel toward the acid-producing anode and form carbonic acid and/or water and carbon dioxide.

Abstract: A flue-gas purification system includes a flue-gas cycling system, a reactor, 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: Combustion flue gas containing NOX and SOX is treated to remove NOX in a multistep system in which NOX is reduced in the flue gas stream via selective catalytic reduction or selective non-catalytic reduction with ammonia or an ammonia-forming compound, followed treatment with hydrogen peroxide to remove residual ammonia and, optionally, treatment with an alkali reagent to reduce residual NOX in the flue gas stream. The NOX-depleted flue gas stream may also be subjected to a desulfurization treatment for removal of SOX.

Abstract: The present invention provides a method and apparatus for removing a contaminant, such as carbon dioxide, from a gas stream, such as ambient air. The contaminant is removed from the gas stream by a sorbent which may be regenerated using a humidity swing, a thermal swing, or a combination thereof. The sorbent may comprise a substrate having embedded positive ions and individually mobile negative ions wherein the positive ions are sufficiently spaced to prevent interactions between the negative ions. Where a thermal swing is used, heat may be conserved by employing a heat exchanger to transfer heat from the regenerated sorbent to an amount of sorbent that is loaded with the contaminant prior to regeneration.

Abstract: A flue-gas purification system includes a flue-gas cycling system, a reactor, 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 wet desulfurizing method for removal of H2S from gaseous stream at normal temperature, the method including: (a) contacting and reacting the gaseous stream containing H2S with a suspension containing desulfurizer in a desulfurization reactor; (b) leading the suspension containing waste agent produced by desulfurizing of desulfurizer after the reaction in step (a) to a regenerative reactor, and regenerating the waste agent using an oxygen-containing gas; (c) leading the suspension containing desulfurizer regenerated in step (b) to the desulfurization reactor in step (a), and contacting and reacting with the gaseous stream containing H2S. A simple method for removing hydrogen sulfide from gas at room temperature and normal pressure, which features high desulfurization rate and low cost.

Abstract: A device and a method for producing a fine liquid mist and injecting the said mist into a gas stream to capture and remove very fine particulate pollutants. The pressurized gas stream is passed into a droplet generator (20) into which the liquid is sprayed and atomised into a mist which captures particulates and then into a droplet separator (30) to produce a separated liquid/particulate mixture and a gas stream with a reduced concentration of particulates. The main application is the removal of fine particulates from vehicle exhaust streams. Optionally a degassing stage (90) is provided for the removal of residual gases and vapours. The preferred liquid to form the mist is water.

Abstract: A method of sequestering a multi-element gas emitted by an industrial plant is described herein, the method comprising: contacting a solution, including a first reactant comprising a multi-element gas emitted by an industrial plant and at least one gas absorber comprising nitrogen, for example ammonia or an amine, with a solid, including a second reactant, under conditions that promote a reaction between the first reactant and the second reactant to provide a first product, which incorporates one or more elements of the multi-element gas, thereby sequestering the multi-element gas.

Abstract: Processes for capturing carbon dioxide are described. The carbon dioxide may be captured from the atmosphere and/or from the waste stream of a carbon dioxide point source (e.g., power plants, chemical plants, natural gas fields, oil fields, industrial sites, etc.). The processes can involve capturing carbon dioxide using alkaline solutions (e.g., NaOH). In some processes, the carbon dioxide may react with the alkaline solution to form a product (e.g., NaHCO3). The alkaline solution may be made a number of different ways. In some of the processes, products produced during processing may be used to add value beyond carbon dioxide capture.

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, mineral sequestration, and solid and liquid sorbents. Methods are also described for extracting and/or capturing CO2 via condensation on solid surfaces at low temperature.

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: Method for cleaning an exhaust gas or a process gas of a manufacturing process of semiconductor components, whereas the exhaust gas or process gas comprises at least one hydrogen chalcogen compound comprising at least one of the following: a) sulfur (S); b) selenium (Se); c) tellurium (Te); and d) polonium (Po), wherein said hydrogen chalcogen compounds are removed in a wet scrubber from the process gas by guiding the process gas into an aqueous solution of at least one base; supplying the least one base to the aqueous solution and extracting an output exhaust gas stream from the aqueous solution, characterized in that the amount of base supplied is controlled such that the pH-value of the solution is larger than 12. The apparatus (1) and the method according to the present invention allow the efficient removal of hydrogen chalcogen compounds from exhaust gases of the production processes of semiconductor compounds like e. g. photovoltaic modules.

Abstract: A method for sequestering carbon dioxide (CO2) that includes generating ammonia from an ammonium salt to make a basic ammoniated aqueous solution and using the solution to remove at least a portion of CO2 from a CO2-bearing gas and precipitate the removed CO2 as bicarbonate. The aqueous solution is recycled. Various valuable byproducts, including sodium bicarbonate, sodium carbonate, ammonium bicarbonate, and hydrochloric acid, are produced. Ammonia is generated by reacting an ammonium salt with either acidic or basic materials. Non-limiting examples of suitable ammonium salt include ammonium chloride, ammonium sulfate, ammonium bisulfate, and ammonia nitrate, those of the acidic material include ammonium bisulfate and sulfuric acid, and those of the basic material include calcium oxide, limestone, dolomite, cement kiln dust, calcium-rich fly ash, steel and iron slag, and silicate rocks or mining wastes that are rich in serpentine, olivine or wollastonite.

Abstract: A gas cleaning system, which is operative for cleaning a process gas containing carbon dioxide and sulphur dioxide, comprises a combined cooling and cleaning system (16), and a CO2-absorber. The combined cooling and cleaning system (16) comprises a first gas-liquid contacting device (50) located upstream of the CO2-absorber and operative for cooling the process gas by means of a cooling liquid, and for absorbing into the cooling liquid sulphur dioxide of the process gas, such that a cooling liquid containing sulphate is obtained. The combined cooling and cleaning system (16) further comprises a second gas-liquid contacting device (94) located downstream of the CO2-absorber and operative for removing ammonia from the process gas, which has been treated in the CO2-absorber, by means of bringing the process gas containing ammonia into contact with the cooling liquid containing sulphate.

Abstract: A chilled ammonia based CO2 capture system and method is provided. A promoter is used to help accelerate certain capture reactions that occur substantially coincident to and/or as a result of contacting a chilled ammonia based ionic solution with a gas stream that contains CO2.

Abstract: Methods and apparatuses are disclosed for the continuous treatment of gas streams contaminated with one or more acid gases, for example HCl, H2S, SO2, SO3, and/or Cl2. At least primary and secondary neutralization zones are utilized, with the secondary neutralization zone being fed by a portion of the gas stream that is used to carry out essentially complete neutralization of a neutralization solution, such as aqueous sodium hydroxide, prior to its disposal (e.g., via biological treatment). The flow of this portion of the gas stream may be regulated by periodically or continuously monitoring the concentration or pH of the spent neutralization solution exiting the secondary neutralization zone. Suitable gas streams that can be treated include effluent gases comprising hydrogen chloride from hydrocarbon conversion processes, particularly paraffin isomerization processes, utilizing a chloriding agent as a catalyst promoter.

Abstract: A method and system for reducing an amount of ammonia in a flue gas stream. The system 100 includes: a wash vessel 180 for receiving an ammonia-containing flue gas stream 170, the wash vessel 180 including a first absorption stage 181a and a second absorption stage 181b, each of the first absorption stage 181a and the second absorption stage 181b having a mass transfer device 184; and a liquid 187 introduced to the wash vessel 180, the liquid 187 for absorbing ammonia from the ammonia-containing flue gas stream 170 thereby forming an ammonia-rich liquid 192 and a reduced ammonia containing flue gas stream 190 exiting the wash vessel 180.

Abstract: A process for reducing hydrogen sulfide from a gas comprising contacting the gas with an aqueous scrubbing liquid recycled from a sour water stripper. The aqueous scrubbing liquid comprises ammonia. The contacting of the gas with the aqueous scrubbing liquid thereby produces a semi-sweet gas with reduced concentration of hydrogen sulfide and a rich liquid solution.

Abstract: The present invention relates to a process for separating off carbon dioxide from gas mixtures by absorption using aqueous alkaline solutions, which comprises carrying out the absorption in a countercurrent flow apparatus in which the gas mixture which is to be worked up and the aqueous alkaline solution used are passed in countercurrent flow and wherein a discontinuous liquid phase forms in the interior of the countercurrent flow apparatus and the separation is carried out in the interior of the countercurrent flow apparatus in the presence of activated carbon, wherein the activated carbon is present in the interior of the countercurrent flow apparatus in an amount of 1 g to 2 kg of activated carbon per m3 of volume of the countercurrent flow apparatus.

Abstract: The present invention provides a process for treating a hydrocarbon feed gas stream containing acid gases (CO2, H2S and mercaptans) by contacting the feed gas stream in a multi-section caustic tower, the bottom sections employing a recirculating caustic solution to remove the CO2 and H2S down to low single digits parts per million concentration and the upper sections employing a stronger caustic solution on a once-through basis to produce a mercaptans depleted gas stream.

Abstract: Methods of sequestering carbon dioxide (CO2) are provided. Aspects of the methods include precipitating a storage stable carbon dioxide sequestering product from an alkaline-earth-metal-containing water and then disposing of the product, e.g., by placing the product in a disposal location or using the product as a component of a manufactured composition. Also provided are systems for practicing methods of the invention.

Abstract: Apparatuses and methods for removing carbon dioxide and other pollutants from a gas stream are provided. The methods include obtaining hydroxide in an aqueous mixture, and mixing the hydroxide with the gas stream to produce carbonate and/or bicarbonate. Some of the apparatuses of the present invention comprise an electrolysis chamber for providing hydroxide and mixing equipment for mixing the hydroxide with a gas stream including carbon dioxide to form an admixture including carbonate and/or bicarbonate.

Abstract: An improved process for deacidizing a gaseous mixture using phase enhanced gas-liquid absorption is described. The process utilizes a multiphasic absorbent that absorbs an acid gas at increased rate and leads to reduced overall energy costs for the deacidizing operation.

Abstract: The present invention describes methods and systems for extracting, capturing, reducing, storing, sequestering, or disposing of carbon dioxide (C02), 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: Ultra cleaning of combustion gas to near zero concentration of residual contaminants followed by the capture of CO2 is provided. The high removal efficiency of residual contaminants is accomplished by direct contact cooling and scrubbing of the gas with cold water. The temperature of the combustion gas is reduced to 0-20 degrees Celsius to achieve maximum condensation and gas cleaning effect. The CO2 is captured from the cooled and clean flue gas in a CO2 absorber (134) utilizing an ammoniated solution or slurry in the NH3—CO2H2O system. The absorber operates at 0-20 degrees Celsius. Regeneration is accomplished by elevating the pressure and temperature of the CO2-rich solution from the absorber. The CO2 vapor pressure is high and a pressurized CO2 stream, with low concentration of NH3 and water vapor is generated. The high pressure CO2 stream is cooled and washed to recover the ammonia and moisture from the gas.

Abstract: A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

Abstract: A method and an apparatus for processing organic material, the method employing at least two reactors and including the steps of combining carbon dioxide or carbon-dioxide containing gas and ammonia or ammonia-containing material in a first reactor to form a buffer compound/buffer compounds, then feeding the buffer compound or buffer compounds formed in the first reactor into a second reactor, and performing bioconversion on organic material in the second reactor. In that case, the carbon dioxide of the mixed carbon dioxide gas reacts with the ammonia, forming a buffer compound, such as ammonium bicarbonate and/or ammonium carbonate.

Abstract: A process is described for sequestering carbon dioxide. In the process, a carbonate, oxide or hydroxide of a divalent cation is reacted with the carbon dioxide and water and/or with a species resulting from the dissolution of the carbon dioxide in water, to form a hydrogen carbonate of the divalent cation. The carbonate, oxide or hydroxide of the divalent cation has a low solubility in water. The divalent cation of the hydrogen carbonate of the divalent cation thus formed is exchanged for a monovalent cation using an ion exchange medium, to produce a solution of a hydrogen carbonate of the monovalent cation.

Abstract: The present invention is directed to an improved method and system for separating and purifying gas using gas-liquid absorption. According to this invention, the method is carried out in an absorber, where a liquid absorbent, a gas mixture containing a gas to be absorbed were introduced from an inlet. During absorption, the second liquid phase was separated out from the absorbent. The absorbed gas was accumulated in one of liquid phases. After absorption, two liquid phases were separated. One of the liquids with rich absorbed gas was forward to regenerator. After regeneration, the liquid was cycled back to absorber. The liquid phase with lean absorbed gas was back to absorber directly to complete the cycle.

Abstract: A process for treating flue gas containing fly ash and carbon dioxide is disclosed. In the process, carbon dioxide and fly ash are contacted with an aqueous metal hydroxide solution to convert carbon dioxide into a metal carbonate, and wherein the metal carbonate and the metal hydroxide cause the fly ash to undergo a geopolymerization reaction and form a geopolymerized fly ash. The geopolymerized fly ash is recovered for disposal or for further use, such as a concrete additive.

Abstract: The present invention provides a method for lowering the rate of injection of activated carbon or carbon based sorbents for control of mercury in coal fired utility systems where the flue gas is also conditioned with SO3 or SO3/NH3 conditioning. The invention replaces the SO3 or SO3/NH3 conditioning by a water based conditioner which does not much adversely affect the efficiency of the injected activated carbon. One such water based conditioner is a composition contained in ATI-2001 available from ARKAY Technologies Inc., 609 Hancock Court, McKees Rocks, Pa. 15136.

Abstract: A new method for the removal of environmental compounds from gaseous streams, in particular, flue gas streams. The new method involves first oxidizing some or all of the acid anhydrides contained in the gas stream such as sulfur dioxide (SO2) and nitric oxide (NO) and nitrous oxide (N2O) to sulfur trioxide (SO3) and nitrogen dioxide (NO2). The gas stream is subsequently treated with aqua ammonia or ammonium hydroxide which captures the compounds via chemical absorption through acid-base or neutralization reactions. The products of the reactions can be collected as slurries, dewatered, and dried for use as fertilizers, or once the slurries have been dewatered, used directly as fertilizers. The ammonium hydroxide can be regenerated and recycled for use via thermal decomposition of ammonium bicarbonate, one of the products formed. There are alternative embodiments which entail stoichiometric scrubbing of nitrogen oxides and sulfur oxides with subsequent separate scrubbing of carbon dioxide.

Abstract: An apparatus and method for treating waste products produced by chemical processing plants. Steam stripping waste sour water results in a vapor including ammonia and hydrogen sulfide. A scrubber unit including a quenching column produces a concentrated ammonium sulfide solution. The concentrated ammonium sulfide allows for more efficient transfer from more than one refinery to a centralized purification facility for further processing.

Abstract: A method for processing organic material, in which method bioconversion is performed on the organic material in at least one first reactor, the biogas formed in the bioconversion is treated with ammonia in at least one second reactor and buffer solution produced in the second reactor is recycled to the bioconversion in the first reactor. Thus, the carbon dioxide of the mixed methane/carbon dioxide gas reacts with the ammonia and forms a buffer compound, such as ammonium bicarbonate and/or ammonium carbonate.

Abstract: A gas combustion treatment method for the combustion treatment of an ammonia-containing gas and a hydrogen sulfide-containing gas, the method comprising a first combustion treatment step in which the ammonia-containing gas, together with a fuel, is introduced and burned; a nitrogen oxide reduction step downstream of the first combustion treatment step, in which a portion of the hydrogen sulfide-containing gas or the ammonia-containing gas is introduced and the nitrogen oxides produced in the first combustion treatment step are reduced in a reducing atmosphere; and a second combustion treatment step downstream of the nitrogen oxide reduction step, in which the remaining hydrogen sulfide-containing gas, together with air, is introduced and burned. The present invention provides a combustion apparatus suitable for use as a combustion furnace for off-gases resulting from the wet purification of coal gasification gas.

Abstract: A process is presented for separating and removing acid gases or base gases from an acid feed gas or a base feed gas, respectively, by use of a gas permeable membrane and caustic or acidic solution. In particular, the process utilizes a caustic or an acidic solution, separated from the base feed gas or acid feed gas by a gas permeable membrane, to react with the base gases, such as, for example, ammonia (NH3), or acid gases, such as, for example, hydrogen cyanide (HCN), hydrogen sulfide (H2S), carbon dioxide (CO2), carbon oxysulfide (COS) and oxides of nitrogen (NOx), to form salts, thereby facilitating the removal of said base gas or said acid gas from the base feed gas or acid feed gas, respectively. In another aspect of the present invention is presented an apparatus for treating a feed gas containing an acid or a base gas wherein the apparatus comprises a feed gas passage; a treatment solution container containing a treatment solution; and a gas permeable membrane.