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 NOR, 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.

A gas purification device removes a part of ammonia contained in a first gas; recovers a first off-gas containing the removed ammonia, removes hydrogen sulfide and ammonia from a second gas produced by removing the part of ammonia, recovers a second off-gas containing the removed hydrogen sulfide and ammonia, and combusts the first off-gas and the second off-gas. The gas purification device includes: a first combustion chamber in which combustion is performed in a reducing atmosphere; a second combustion chamber in which combustion is performed in a reducing atmosphere downstream of the first combustion chamber; and a third combustion chamber in which combustion is performed in an oxidizing atmosphere downstream of the second combustion chamber. The first off-gas flows into the first combustion chamber and the second off-gas flows into the third combustion chamber.

A gas purification device removes a part of ammonia contained in a first gas; recovers a first off-gas containing the removed ammonia, removes hydrogen sulfide and ammonia from a second gas produced by removing the part of ammonia, recovers a second off-gas containing the removed hydrogen sulfide and ammonia, and combusts the first off-gas and the second off-gas. The gas purification device includes: a first combustion chamber in which combustion is performed in a reducing atmosphere; a second combustion chamber in which combustion is performed in a reducing atmosphere downstream of the first combustion chamber; and a third combustion chamber in which combustion is performed in an oxidizing atmosphere downstream of the second combustion chamber. The first off-gas flows into the first combustion chamber and the second off-gas flows into the third combustion chamber.

Methods and systems described perform air cleaning and/or sanitization in a heating, ventilation, air conditioning, and/or refrigeration (HVACR) system by detecting a concentration of airborne contaminants in a space serviced by the HVACR system. The detected concentration of airborne contaminants is determined whether it exceeds a threshold relative to a capacity of a first air cleaner. When the detected concentration of airborne contaminants exceeds the threshold, a second air cleaner is selected and enabled to be activated in the space. When the detected concentration of airborne contaminants does not exceed the threshold, the first air cleaner is selected and enabled to be activated in the space. The first air cleaner has a cleaning material different from the second air cleaner, and the first air cleaner, relative to the second air cleaner, treats the space at a lower concentration of airborne contaminants. The second air cleaner includes specifically designed cleaner modules.

Methods and systems described perform air cleaning and/or sanitization in a heating, ventilation, air conditioning, and/or refrigeration (HVACR) system by detecting a concentration of airborne contaminants in a space serviced by the HVACR system. The detected concentration of airborne contaminants is determined whether it exceeds a threshold relative to a capacity of a first air cleaner. When the detected concentration of airborne contaminants exceeds the threshold, a second air cleaner is selected and enabled to be activated in the space. When the detected concentration of airborne contaminants does not exceed the threshold, the first air cleaner is selected and enabled to be activated in the space. The first air cleaner has a cleaning material different from the second air cleaner, and the first air cleaner, relative to the second air cleaner, treats the space at a lower concentration of airborne contaminants. The second air cleaner includes specifically designed cleaner modules.

According to one embodiment, a gas processing equipment includes an oxygen remover 2 that removes oxygen contained in exhaust gas G, and a gas processing device 3 that processes pretreated exhaust gas G (P), from which the oxygen has been removed by the oxygen remover 2, with a carbon dioxide absorbent solvent S as a treatment agent.

According to one embodiment, a gas processing equipment includes an oxygen remover 2 that removes oxygen contained in exhaust gas G, and a gas processing device 3 that processes pretreated exhaust gas G (P), from which the oxygen has been removed by the oxygen remover 2, with a carbon dioxide absorbent solvent S as a treatment agent.

One aspect of the invention relates to a method comprising a single stage conversion of an atmospheric pollutant, such as NO, NO.sub.2 and/or SO.sub.x in a first stream to one or more mineral acids and/or salts thereof by reacting with nonionic gas phase chlorine dioxide (ClO.sub.2.sup.0 , wherein the reaction is carried out in the gas phase. Another aspect of the invention relates to a method comprising first adjusting the atmospheric pollutant concentrations in a first stream to a molar ratio of about 1:1, and then reacting with an aqueous metal hydroxide solution (MOH). Another aspect of the invention relates to an apparatus that can be used to carry out the methods disclosed herein. The methods disclosed herein are unexpectedly efficient and cost effective, and can be applied to a stream comprising high concentration and large volume of atmospheric pollutants.

One aspect of the invention relates to a method comprising a single stage conversion of an atmospheric pollutant, such as NO, NO.sub.2 and/or SO.sub.x in a first stream to one or more mineral acids and/or salts thereof by reacting with nonionic gas phase chlorine dioxide (ClO.sub.2.sup.0 , wherein the reaction is carried out in the gas phase. Another aspect of the invention relates to a method comprising first adjusting the atmospheric pollutant concentrations in a first stream to a molar ratio of about 1:1, and then reacting with an aqueous metal hydroxide solution (MOH). Another aspect of the invention relates to an apparatus that can be used to carry out the methods disclosed herein. The methods disclosed herein are unexpectedly efficient and cost effective, and can be applied to a stream comprising high concentration and large volume of atmospheric pollutants.

An exhaust hood may have an exhaust inlet; a shroud having a lower edge and being movable, the shroud being configured to define an enclosed space over and adjacent a cooking surface, the enclosed space being in communication with the exhaust inlet. The shroud is movable to a first position providing clearance between the cooking surface and the shroud lower edge and a second position providing substantially less than the clearance provided by the first position. A vertical jet at the lower edge is aimed upwardly and along an inside of the shroud when the shroud is in the second position and the vertical jet is in the enclosed space. A horizontal jet is provided at a top of the shroud and aimed along an inside of the shroud when the shroud is in the second position and the vertical jet being in the enclosed space.