Systems and methods of continuous operation of a urea-SCR system at low temperatures (200-350° C.) in the presence of high SOx containing flue gas are described. The methods comprise introducing a solution of urea and an NO.sub.2 forming compound, preferably an alkaline earth metal nitrate, into an exhaust stream before the exhaust stream contacts an SCR catalyst.

A method for purifying air within a space is provided. The method includes a controller determining whether an ON signal is received. Upon determining that the ON signal is received, the controller instructs an air sanitizer of an air sanitization system to turn ON to purify an airflow passing through the air sanitization system, and instructs an air movement fan/blower to operate in order to direct the airflow into the space. Upon determining that the ON signal is not received, the controller instructs the air movement fan/blower and the air sanitizer to be OFF.

Air filtration apparatuses, systems and methods for nitrous oxide and volatile organic compound (VOC) removal and non-VOC particle removal enable the removal of particulates, nitrous oxide-containing compounds, and volatile organic compounds from large volume enclosed environments. Systems incorporate HEPA filtration upstream from UV LED-assisted photo reaction chamber comprising a plurality of baffles having air flow-through airflow spaces are spaced apart along a duct, with a porous and permeable nitrous oxide-adsorbing filter oriented downstream from the UV-assisted photo reaction chamber further filtering the airflow in the system to remove nitrous oxide-containing compounds.

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.

An apparatus and method for treating a semiconductor process gas comprises a gas inlet allowing a treatment target gas (or gas to be treated) to flow therethrough; a catalytic reaction portion including a catalyst and configured to allow the treatment target gas to be brought into contact with the catalyst; a space velocity controller between the gas inlet and the catalytic reaction portion, the space velocity controller extending from the gas inlet in a diagonal direction in relation to the gas inlet; a differential pressure buffer portion between the space velocity controller and the catalytic reaction portion and including a filter; and a gas outlet configured to externally discharge a product formed as the treatment target gas comes into contact with the catalyst.

In a high-efficient clean, high-variable load rate coal-fired power generation system, through the internal thermal source SCR denitration catalytic module coupled with high temperature and low temperature storage tanks, the operating temperature of the internal thermal source SCR denitration catalytic module is controlled in a range of 300° C. to 400° C., ensuring that the SCR catalyst has high activity in full-working conditions. Moreover, the high temperature and low temperature storage tanks are coupled with the high-pressure heater group for steam turbine regenerative system, so that when the coal-fired unit needs to increase load rate, the thermal storage energy is quickly converted into output power. In addition, energy stored in the high temperature and low temperature storage tanks come from both the internal thermal source SCR denitration catalytic module and the thermal storage medium heater within the boiler, the operational flexibility and the boiler efficiency are improved.

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 process for converting post-explosion gases of an inhabitable level, low-oxygen ambient environment to a breathable mixture for human consumption comprises receiving a flow of post-explosion gas with oxygen, carbon dioxide, carbon monoxide, nitrogen, and methane. The oxygen, carbon monoxide, and carbon dioxide are removed from the from the flow of post-explosion gas to create both a mixture including oxygen, carbon monoxide, and carbon dioxide; and a residual stream including nitrogen and methane. The oxygen is removed from the mixture of oxygen, carbon monoxide, and carbon dioxide, and concentrated in a primary oxygen storage canister. The nitrogen is removed from the residual stream and stored in a nitrogen storage canister separate from the oxygen storage canister. The methane is vented back to the inhabitable level, low-oxygen ambient environment. The stored oxygen and nitrogen are metered through a breathing mask at a habitable level of 19-21% oxygen to a user.

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.

An exhaust gas treatment device includes an exhaust gas line where a combustion exhaust gas discharged from a power generation facility flows through, an exhaust gas line where a second combustion exhaust gas discharged from a second power generation facility flows through, exhaust gas exhaust line disposed by branching off from exhaust gas line, discharging a part of combustion exhaust gases as exhaust combustion exhaust gases, a nitrogen oxide removing unit removing nitrogen oxide contained in an integrated combustion exhaust gas that integrates the combustion exhaust gases, an integrated waste heat recovery boiler recovering waste heat from the integrated combustion exhaust gas, and a CO.sub.2 recovery unit recovering CO.sub.2 contained in the integrated combustion exhaust gas by using CO.sub.2 absorbing liquid.