Disclosed herein is a system for recovering flash gas from an oil storage tank. In one example of the invention, the system may include a flexible storage tank that receives the flash gas and temporarily stores the flash gas; a compressor having an input receiving the flash gas from the flexible storage tank, the compressor compressing the flash gas to form compressed gas; and an oxygen reduction subsystem receiving the compressed gas, the oxygen reduction subsystem reducing an amount of oxygen from the compressed gas. In this manner, the resulting compressed oxygen-reduced gas that has been recovered can be injected into a sales gas line for use, under certain conditions.

The invention describes a process for the photocatalytic reduction of carbon dioxide carried out in the liquid phase and/or in the gas phase under irradiation employing a photocatalyst of microporous crystalline metal sulfide type, said process being carried out by bringing a charge containing the CO.sub.2 and at least one sacrificial compound into contact with said photocatalyst, then by irradiating the photocatalyst by at least one irradiation source producing at least one wavelength lower than the bandgap width of said photocatalyst, so as to reduce the CO.sub.2 and to oxidize the sacrificial compound, so as to produce an effluent containing, at least in part, C.sub.1 or more carbon-based molecules other than CO.sub.2.

In accordance with some embodiments herein, a filtering product is provided. The filtering product includes titanium dioxide (TiO.sub.2), cetrimonium bromide (CTAB) and ascorbic acid (C.sub.6H.sub.8O.sub.6). The filtering product may be used for filtering smoke of a water pipe. Alternatively and/or additionally, the filtering product may be used for filtering gas.

The present invention relates to a VOC reduction system and a VOC reduction method that applies pulse type thermal energy to a catalyst to activate the catalyst and oxidizes and removes the VOC.

There is provided an exhaust gas purification system that allows efficient purification of NOx present in exhaust gas emitted from an internal combustion engine. The exhaust gas purification system of the disclosure comprises a first exhaust gas purification device that purifies exhaust gas emitted from an internal combustion engine, wherein the atmosphere alternately switches between a reducing agent-excess atmosphere and an oxidizing agent-excess atmosphere with respect to the stoichiometric atmosphere, and a second exhaust gas purification device that further purifies the exhaust gas that has been purified by the first exhaust gas purification device, wherein the first exhaust gas purification device has a three-way catalyst, and the second exhaust gas purification device has an exhaust gas purifying catalyst that comprises an AMn.sub.2O.sub.4 spinel-type oxide support (A=Mg, Zn or Li) on which a precious metal is supported.

Provided is a combustion system in which a catalyst having superior denitration efficiency at a low temperature compared with those used in the conventional techniques is used in a selective catalytic reduction reaction using ammonia as a reducing agent. A combustion system equipped with: a denitration device which is arranged in the exhaust passage and can remove a nitrogen oxide from the exhaust gas with a denitration catalyst. In the combustion system, the denitration device is arranged on the downstream side of the dust collection device in the exhaust passage, and the denitration catalyst is one which contains vanadium oxide as the main component and in which the content of a second metal in terms of oxide content is 1 to 40 wt % inclusive, wherein the second metal comprises at least one metal element selected from the group consisting of Co, W, Mo, Nb, Ce, Sn, Ni, Fe, Cu, Zn and Mn.

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.

A glass fiber filter element for visible light photocatalysis and air purification and a method for preparing the same. The glass fiber filter element includes 4 to 7 wt % of nanoparticles including at least one selected from zinc oxide, graphene oxide, titanium oxide, and reduced graphene oxide, 2 to 7 wt % of silver nanowires, 3 to 12 wt % of an adhesive system, and 78 to 91 wt % of a glass fiber mat, based on the total weight of the glass fiber filter element. The glass fiber mat is made of at least two glass fibers with different diameters, and the diameters are in a range of 0.15 to 3.5 μm. The nanoparticles have a particle size from 1 to 200 nm, and the silver nanowires have a diameter of 15 to 50 nm.

When the porous ceramic structure contains Co together with Fe or Mn, the Co content is higher than or equal to 0.1 mass % and lower than or equal to 3.0 mass % in terms of Co.sub.3O.sub.4, and when the porous ceramic structure contains Co without containing Fe and Mn, the Co content is higher than or equal to 0.2 mass % and lower than or equal to 6.0 mass % in terms of Co.sub.3O.sub.4. The Ce content is higher than or equal to 0.1 mass % and lower than or equal to 10 mass % in terms of CeO.sub.2. The Fe/Mn/Co ratio is higher than or equal to 0.8 and lower than or equal to 9.5. The porous ceramic structure contains more than or equal to 0.03 percent and less than or equal to 2.5 percent by mass of Zn in terms of ZnO.

Fluid purification systems employing a monolithic composite photocatalyst to remove volatile organic compounds (VOCs) and/or pathogenic organisms are disclosed. Pairing of systems tuned to abate each of these materials are discussed in different configurations such as series and parallel, as well as combining systems to target both materials simultaneously. System configurations that allow a portion of the fluid stream to be purified are also disclosed as are configurations that allow regeneration of the photocatalyst. These features may be augmented by sensors that allow closed loop control of bypass and regeneration cycles in the systems.