This invention is directed to a method used to remove gases from industrial exhaust streams, and in particular, to a method for removing sulfur dioxide from flue gases, with molten carbonate and treating the resulting molten mixture with a natural gas and optionally with an oxidant.

A method for removing methane and non-methane volatile organic compound concentrations from a gas stream. The method includes exposing the target gas to a halogen gas and a light from a suitable light source having a wavelength sufficient to activate halogen gas to halogen radicals, wherein the halogen radicals react with the VOC in the target gas to provide the target gas with a removed concentration of VOC as well as a device including a reaction chamber for reacting the halogen radicals with the VOC in the target gas.

A fuel tank inerting system is disclosed. In addition to a fuel tank, the system includes a catalytic reactor with an inlet, an outlet, a reactive flow path between the inlet and the outlet, and a catalyst on the reactive flow path. The catalytic reactor is arranged to receive fuel from the fuel tank and air from an air source, and to react the fuel and air along the reactive flow path to generate an inert gas. The system also includes an inert gas flow path from the catalytic reactor to the fuel tank. The system also includes (a) an air distributor in the catalytic reactor arranged to distribute air along the reactive flow path, or (b) non-uniform catalyst loading or non-uniform catalyst composition along the reactive flow path, or both (a) and (b).

Disclosed is an exhaust emission control device having a particulate filter 3 and a selective reduction catalyst 4 arranged in parallel with each other such that entry sides of them are directed in a same direction. A communication passage 16 is arranged to oppositely turn exhaust gas 1 from an exit side of the selective reduction filter 3 into the entry side of the adjacent selective reduction catalyst 4. The urea water (reducing agent) is addable upstream of the communication passage 16. The communication passage 16 is stepwisely turned to the entry side of the adjacent selective reduction catalyst 4 through bending portions x and y downstream of an added position of the urea water. At least the most upstream bending portion x is formed to have a bending angle when viewed from an axial direction of the selective reduction filter 3.

The present invention provides an energy-efficient method and apparatus that can achieve exhaust gas abatement with a minimum use of diluent nitrogen gas. More specifically, the present invention is directed to a method and apparatus for exhaust gas abatement under reduced pressure, in which an exhaust gas supplied from an exhaust gas source through a vacuum pump is decomposed by combustion heat of a flame under a reduced pressure.

A method for treating a crude natural gas feed stream comprising methane and having a first carbon dioxide concentration, said method comprising the steps of: subjecting the crude natural gas feed stream to a separation process to provide: a purified natural gas stream having a second carbon dioxide content which is lower than the first carbon dioxide concentration in said crude natural gas stream; and, a carbon dioxide stream comprising carbon dioxide as the major component and methane; recovering the purified natural gas steam; optionally mixing the carbon dioxide stream with make-up methane and/or make-up air; passing the carbon dioxide stream and optional make-up methane or air through a heat exchanger to raise the temperature of the stream to the desired inlet temperature T.sub.1 of an oxidation reactor; optionally mixing the carbon dioxide stream with make-up methane and/or make-up air; passing the heated stream from step (d) and any optional make-up methane and/or air to the oxidation reactor containing an oxidation catalyst, where the methane is oxidised; removing a gas stream including the products of the oxidation reaction from the reactor, said gas stream being at an outlet temperature T.sub.2 which is higher than the inlet temperature T.sub.1; passing the gas stream removed in step (g) through the heat exchanger against the carbon dioxide stream from step (a) to allow the heat to be recovered from the gas stream removed in step (g) and utilised to heat the carbon dioxide stream in step (d); and measuring the outlet temperature T.sub.2 and controlling the inlet temperature T.sub.1 by adjusting the amount of make-up methane and/or air added in step (c) and/or step (e).

A combustion device includes an ammonia supply unit supplying primary reduction ammonia as a nitrogen oxide reducing agent into a combustor and mixing secondary reduction ammonia with combustion exhaust gas discharged from the combustor to reduce nitrogen oxide contained in the combustion exhaust gas and a controller configured to control at least one of the amount of supply of the primary reduction ammonia and the amount of mixing of the secondary reduction ammonia with the combustion exhaust gas in accordance with concentrations of residual nitrogen oxide and residual ammonia contained in the combustion exhaust gas after being discharged from the combustor.

A hydrothermal method of preparing uniform, monodisperse ceramic lanthanum hydroxyl carbonate (LaCO.sub.3OH) having cherry-blossom-like nanogears and/or nanocubes is described. The method produced a hexagonal crystal with a crystal lattice in which at least on lanthanum ion is substituted with calcium ion. The ceramic nanoparticles produced by the method are good catalyst for the reduction of nitrogen oxides with a hydrocarbon. A method of reducing exhaust gases is described.

Described herein are methods and systems for processing gas streams. The gas streams may comprise a methane-containing gas stream, such as an exhaust stream. The systems and methods of the present disclosure may process the methane-containing gas stream using one or more processing units including a biological filtration unit and a thermal oxidizer to generate an output stream which has a lower concentration of methane than the methane-containing gas stream.

A catalytic composition for treating a NOx-containing exhaust gas, wherein the composition comprises a copper-substituted zeolite comprising: i) Ce in a total amount of about 0.1 to about 200 g/ft.sup.3; and ii) Mn in a total amount of about 0.1 to about 200 g/ft.sup.3.