Method for reducing the content of nitrogen oxides NOx and nitrous oxide N2O in an input gas, comprising the steps of: treating said gas with a first amount of a NOx reducing agent in a first de-NOx catalytic bed; treating the effluent of said first de-NOx catalytic bed in at least one de-N2O catalytic bed for removal of N2O; treating the effluent of said at least one de-N2O catalytic bed with a second amount of a NOx reducing agent in a second de-NOx catalytic bed.

A metal oxide catalyst synthesized using supercritical carbon dioxide extraction is provided, wherein the metal oxide catalyst includes an active site containing at least one type of metal oxide and a support for loading the active site and the metal oxide is an oxide of a metal selected from the group consisting of transition metals (atomic number 21 to 29, 39 to 47, 72 to 79, or 104 to 108), lanthanide (atomic number 57 to 71), post-transition metals (atomic number 13, 30 to 31, 48 to 50, 80 to 84, and 112), and metalloids (atomic number 14, 32 to 33, 51 to 52, and 85) in the periodic table, and a combination thereof.

An object of the present invention is to provide a new frameless catalytic thermal oxidation device capable of treating concentrations of harmful materials including NOx at a low temperature. Further, another object of the present invention is to provide a frameless catalytic thermal oxidation device capable of minimizing the occurrence of THC and minimizing a risk of accidents and environmental pollution which may occur in maintenance operations. According to the objects, the present invention provides a cartridge-type thermal oxidation device capable of being separated for maintenance, wherein a cartridge internal structure is configured so that the time while the material to be treated stays in a zone with the catalyst is increased, and a member capable of dropping and collecting powder generated by thermal oxidation reaction is configured.

A fresh air ventilation device for air pollution prevention includes a main body, a blower, a filtering and cleaning assembly, and a gas detection module. The blower is disposed in the main body to guide air convection and form a flow-guiding path. The filtering and cleaning assembly is disposed in the flow-guiding path to filter and clean an air pollution source in the air convection guided by the blower. The gas detection module is disposed in the flow-guiding path of the main body to detect the air pollution source and transmit a gas detection data.

Indoor and outdoor air purifier including:—a fan for suctioning air and conveying it into—an air treatment duct suitable to disintegrate the toxic and pollutant components present in the air and then reintroducing the air, purified by now, into the external environment through one of the grids; within the duct, at least the following being installed: ∘ filters in any alveolar ceramic alloy treated with a titanium dioxide TiO.sub.2 nano-coating suitable to disintegrate the pollutant substances by a photocatalytic process activated thanks to ∘ LED lights, each of which installed in proximity to a corresponding filter, suitable to start the pollutant molecules disintegration photocatalytic process, reintroducing only the harmless substances into the atmosphere.

A reactor for reducing the concentration of NOx in a stream comprising: an inlet for the stream; an outlet for a stream containing a reduced concentration of NOx; one or more catalyst beds comprising a ceramic or metallic foam with a NOx reduction catalyst; one or more flow paths from the inlet to the outlet that passes through at least one catalyst bed wherein the catalyst beds are closed at the top and bottom so that the flow path through the catalyst bed passes through the sides of the catalyst bed in a lateral flow is described.

An exhaust gas treatment device includes an exhaust gas line through which a combustion exhaust gas discharged from a power generation facility flows, a waste heat recovery boiler recovering waste heat of the combustion exhaust gas, a branch exhaust gas line provided to be connected between a front stage and a downstream stage of the waste heat recovery boiler on a main exhaust gas line, a nitrogen oxide removal unit removing nitrogen oxide in an integrated combustion exhaust gas into which a combustion exhaust gas flowing through the main exhaust gas line and a combustion exhaust gas flowing through the branch exhaust gas line are integrated, an integrated waste heat recovery boiler recovering waste heat of the integrated combustion exhaust gas from which nitrogen oxide has been removed, and a CO.sub.2 recovery unit recovering CO.sub.2 in the integrated combustion exhaust gas.

Some embodiments of the present disclosure relate to a method of regenerating at least one filter medium comprising: providing at least one filter medium, wherein the at least one filter medium comprises: at least one catalyst material; and ammonium bisulfate (ABS) deposits, ammonium sulfate (AS) deposits, or any combination thereof; flowing a flue gas stream transverse to a cross-section of a filter medium, such that the flue gas stream passes through the cross section of the at least one filter medium, wherein the flue gas stream comprises: NOx compounds comprising: Nitric Oxide (NO), and Nitrogen Dioxide (NO.sub.2); and increasing an NOx removal efficiency of the at least one filter medium after removal of deposits.

The present disclosure provides catalyst compositions for NO.sub.x conversion and wall-flow filter substrates comprising such catalyst compositions. Certain catalyst compositions include a zeolite with sufficient Cu exchanged into cation sites thereof to give a Cu/Al ratio of 0.1 to 0.5 and a CuO loading of 1 to 15 wt. %; and a copper trapping component (e.g., alumina) including a plurality of particles having a D.sub.90 particle size of about 0.5 to 20 microns in a concentration of about 1 to 20 wt. %. The zeolite and copper trapping component can be in the same washcoat layer or can be in different washcoat layers (such that the copper trapping component serves as a “pre-coating” on the wall-flow filter substrate).

A method for flue gas denotation includes the step of, in the presence of ammonia, enabling flue gas in a denitration reactor to pass through a plurality of catalyst beds from the bottom to the top to participate in a denitration reaction. Each catalyst bed contains a catalyst support component and a granular denitration catalyst stacked on the catalyst support component, and, in every single catalyst bed, the granular denitration catalyst moves along a same direction on the catalyst support component. Between every two adjacent catalyst beds, the granular denitration catalyst falls from the tail of a previous catalyst support component to the head of a next catalyst support component, making the granular denitration catalyst travel along the catalyst support components reciprocatively.