Disclosed are a flue gas purification and waste heat utilization system and method. The system comprises a flue gas exhaust unit, a primary waste heat utilization unit, a primary flue gas purification unit, a secondary waste heat utilization unit and a secondary flue gas purification unit that are sequentially connected in a flue gas flow direction, wherein the primary flue gas purification unit is configured for removing NO.sub.x, large particles and CO in the flue gas, the secondary flue gas purification unit is configured for removing NO.sub.x and dioxin in the flue gas, an ammonia-spraying device is externally connected between the flue gas exhaust unit and the primary waste heat utilization unit, and the ammonia-spraying device is configured for injecting ammonia gas into the flue gas exhausted from the flue gas exhaust unit.

An object of the present invention is to provide a composition for forming an undercoat layer capable of forming an undercoat layer that does not easily peel off from the substrate, an undercoat layer formed by the composition, as well as an exhaust gas purification catalyst and an exhaust gas purification apparatus each including the undercoat layer, and, to achieve the object, the present invention provides a composition for forming an undercoat layer, the composition containing tin oxide microparticles and tin oxide nanoparticles, wherein a content of the tin oxide nanoparticles is 8% by mass or more and 30% by mass or less, with respect to a total content of the tin oxide microparticles and the tin oxide nanoparticles, an undercoat layer formed by the composition, as well as an exhaust gas purification catalyst and an exhaust gas purification apparatus each including the undercoat layer.

Provided herein is a catalytic article including a catalytic coating disposed on a substrate, wherein the catalytic coating comprises a bottom coating on the substrate and a top coating layer on the bottom coating layer, one such coating layer containing a platinum group metal on a refractory metal oxide support and the other such coating layer containing a ceria-containing molecular sieve. Such catalytic articles are effective toward treating exhaust gas streams of internal combustion engines and exhibit outstanding resistance to sulfur.

Disclosed are a flue gas purification and waste heat utilization system and method. The system comprises a flue gas exhaust unit, a primary waste heat utilization unit, a primary flue gas purification unit, a secondary waste heat utilization unit and a secondary flue gas purification unit that are sequentially connected in a flue gas flow direction, wherein the primary flue gas purification unit is configured for removing NO.sub.x, large particles and CO in the flue gas, the secondary flue gas purification unit is configured for removing NO.sub.x and dioxin in the flue gas, an ammonia-spraying device is externally connected between the flue gas exhaust unit and the primary waste heat utilization unit, and the ammonia-spraying device is configured for injecting ammonia gas into the flue gas exhausted from the flue gas exhaust unit.

An oxygen scavenging system that includes a first catalytic converter unit configured to receive an exhaust stream from a power production unit. The exhaust stream includes oxygen. The system also includes a hydrocarbon injection unit configured to channel a hydrocarbon stream for injection into the exhaust stream upstream from the first catalytic converter unit such that hydrocarbons from the hydrocarbon stream react with the oxygen from the exhaust stream within the first catalytic converter unit.

Systems and methods for controlling emissions from industrial sources are provided. The system includes an industrial air treatment device that captures emissions from a stack, such as an industrial flare. The industrial air treatment device does not fully encompass or enclose the stack, but allows for ambient air flow with the emissions flow. The industrial air treatment device is separate from and not incorporated into the stack. The industrial air treatment device contains fans to draw in the emissions and air flow, and filters to treat the air flow. At least one of the filters can include a water dispersal system that captures and removes pollutants. The filters can include activated carbon, demister pads, and catalytic converters. The industrial air treatment device releases the treated air to the atmosphere.

Systems and methods for controlling emissions from industrial sources are provided. The system includes an industrial air treatment device that captures emissions from a stack, such as an industrial flare. The industrial air treatment device does not fully encompass or enclose the stack, but allows for ambient air flow with the emissions flow. The industrial air treatment device is separate from and not incorporated into the stack. The industrial air treatment device contains fans to draw in the emissions and air flow, and filters to treat the air flow. At least one of the filters can include a water dispersal system that captures and removes pollutants. The filters can include activated carbon, demister pads, and catalytic converters. The industrial air treatment device releases the treated air to the atmosphere.

Provided herein is a catalytic article including a catalytic coating disposed on a substrate, wherein the catalytic coating comprises a bottom coating on the substrate and a top coating layer on the bottom coating layer, one such coating layer containing a platinum group metal on a refractory metal oxide support and the other such coating layer containing a ceria-containing molecular sieve. Such catalytic articles are effective toward treating exhaust gas streams of internal combustion engines and exhibit outstanding resistance to sulfur.

The invention relates to a noxious gas purificant and its preparation and purification method for removing nitrogen oxides from gas streams thereof. The preparing method is characterized in that: mixing, according to a predetermined ratio and a process, a salt of iron, manganese, cobalt, or copper, and a related derivative thereof, an alkali or alkaline substance and a related derivative thereof, water and a forming agent, so as to obtain a solid compound or mixture; drying and activating the solid compound or mixture to produce a solid product as the purificant; and introducing the purificant into a gas-solid reactor, and removing noxious gases in a gas stream by performing, in a preconfigured temperature and using the purificant, a gas-solid reaction on the harmful gases in the gas stream. The purificant can be recycled and reused.

This invention provides a multinary solid solution fine particle represented by Pd.sub.xRu.sub.yM.sub.z (M is at least one member selected from the group consisting of Rh, Pt, Cu, Ag, Au and Ir. x+y+z=1, x+y=0.01 to 0.99, z=0.99 to 0.01, x:y=0.1:0.9 to 0.9:0.1), a method for producing the same, and a supported catalyst.