A method of removing carbon dioxide from an atmosphere and generating hydrogen includes capturing carbon dioxide from the atmosphere in an alkaline capture solution, sending the alkaline capture solution to a series of electrolyzers in a CO.sub.2-rich path, wherein each electrolyzer cell raises the acidity of the input CO.sub.2-rich solution to produce an acidified CO.sub.2-rich solution, removing carbon dioxide from the acidified CO.sub.2-rich solution at a carbon dioxide removal unit operation to produce a CO.sub.2-poor solution, sending the CO.sub.2-poor solution to the series of electrolyzers in a return path, wherein each electrolyzer raises the alkalinity of the return CO.sub.2-poor solution to produce a basified CO.sub.2-poor solution, wherein a difference in pH between the CO.sub.2-rich solution and the CO.sub.2-poor solution within each electrolyzer is less than 3, and returning the basified CO.sub.2-poor solution to the carbon dioxide capture unit operation.

A desulfurization gas process includes water vapor, CO.sub.2 and SO.sub.x (x=2 and/or 3). In a treatment unit, the gas contacts a cooled alkaline aqueous solution having a temperature lower than an initial gas temperature, water and a carbonate of an alkali metal, to cool the gas, condense some water vapor and absorb SO.sub.x in the carbonate-containing solution, produce an SO.sub.x-depleted gas and an acidic aqueous solution including sulfate and/or sulfite ions. The SO.sub.x-depleted gas and a portion of the acidic aqueous solution can then be withdrawn from the treatment unit. Carbonate of the alkali metal can be added to remaining acidic aqueous solution to obtain a made-up alkaline aqueous solution. This solution can be cooled and reused as the cooled alkaline aqueous solution. An SO.sub.x absorbent solution includes a bleed stream from a CO.sub.2-capture process, sodium or potassium carbonate, and an acidic aqueous solution obtained from desulfurization.

The removal of carbon dioxide using sequestration materials that include salts in molten form, and related systems and methods, are generally described.

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.

According to an embodiment of the present disclosure, an exhaust gas treatment apparatus may include: a preprocessor configured to primarily remove harmful substances from exhaust gas produced by combustion; and a postprocessor configured to further remove harmful substances from preprocessed gas, which is the exhaust gas from which the harmful substances have been primarily removed by the preprocessor, wherein the postprocessor may include a postprocessor housing having a preprocessed gas inlet through which the preprocessed gas is introduced and a postprocessed gas outlet through which postprocessed gas from which harmful substances have been further removed by the postprocessor is discharged and forming a flow path of the preprocessed gas therein, and a diffuser disposed adjacent to the preprocessed gas inlet and configured to diffuse the preprocessed gas introduced through the preprocessed gas inlet.

An injection lance assembly for creating a higher degree of turbulence and dispersion of a treating agent into a fluid stream.

A fluid network controls a gaseous flow, the fluid network having several pre-concentration units including at least one first series in which the pre-concentration units are linked in series and each defined by a rank j in the series, with j ranging from 1 to m and m being greater than or equal to 2. Each pre-concentration unit of the network includes a cavity filled with an adsorbent material, at least one first fluid pathway emerging in the cavity, at least one second fluid pathway emerging in the cavity. Finally, each pre-concentration unit includes a component for heating the cavity.

The disclosure provides seven integrated methods for the chemical sequestration of carbon dioxide (CO.sub.2), nitric oxide (NO), nitrogen dioxide (NO.sub.2) (collectively NO.sub.x, where x=1, 2) and sulfur dioxide (SO.sub.2) 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 CO.sub.2, NOx and SO.sub.2. The integrated technology combines compatible and green processes that capture and/or convert CO.sub.2, NOx and SO.sub.2 into compounds that enhance the environment, many with commercial value.

Disclosed is an exhaust gas purification system, including: a cathode unit including a first accommodation space, a first aqueous solution, and a cathode at least partially submerged in the first aqueous solution; an anode unit including a second accommodation space, a second aqueous solution which is basic, and a metal anode at least partially submerged in the second aqueous solution; and a connection unit configured to connect the cathode unit and the anode unit. The anode is made of aluminum (Al) or zinc (Zn), a gas containing nitrogen oxide (NO.sub.x) is injected into the first aqueous solution, the nitrogen oxide injected into the first aqueous solution reacts with water to produce nitric acid (HNO.sub.3), the nitric acid supplies hydrogen ions, and the hydrogen ions and electrons of the cathode react to produce hydrogen.

A device and method for removing pollutants from the air including a reaction unit containing a reaction fluid dispersion medium such as film fill, a reaction fluid distribution system for distributing an aqueous reaction solution over the reaction fluid dispersion medium, and an air mover, located above the reaction fluid distribution system and reaction fluid dispersion medium, for drawing or forcing air into the reaction unit to contact the sodium or potassium hydroxide. The pollutant in the air reacts with the aqueous reaction solution to form an aqueous reaction product thus removing the pollutant from the air. The device may include humidifiers to humidify the ambient air before it contacts the reaction fluid.