A contaminant reducing device is provided. The contaminant reducing device comprises: an exhaust gas tube for supplying exhaust gas from a combustion engine; a cleaning water supply tube for supplying cleaning water; a scrubber for spraying cleaning water, which is supplied through the cleaning water supply tube, to exhaust gas supplied through the exhaust gas tube; an oxidation unit connected to the exhaust gas tube so as to oxidize the exhaust gas by discharging electricity, emitting ultraviolent rays, or spraying an oxidizer; and a cleaning water discharge tube for discharging cleaning water from inside the scrubber.

A method for treating sulfur contaminants is provided. The method comprises introducing a methylmorpholine-N-oxide solution to a vessel, wherein the vessel comprises a water layer and a gas layer, wherein the water layer and the gas layer comprise the hydrogen sulfide; introducing methylmorpholine-N-oxide into the water layer; and treating the water layer by allowing the methylmorpholine-N-oxide to react with the hydrogen sulfide.

Certain functionalized aldehydes scavengers may be used to at least partially scavenge sulfur-containing contaminants from fluid systems containing hydrocarbons and/or water. The contaminants scavenged or otherwise removed include, but are not necessarily limited to, H.sub.2S, mercaptans, and/or sulfides. Suitable scavengers include, but are not necessarily limited to, reaction products of glycolaldehyde with aldehydes; reaction products of glycolaldehyde with a nitrogen-containing reactant (e.g. an amine, a triazine, an imine, an aminal, and/or polyamines); non-nitrogen-containing reaction products of a hydrated aldehyde with certain second aldehydes; reaction products of 1,3,5-trioxane with hydroxyl-rich compounds (e.g. glyoxal, polyethylene glycol, polypropylene glycol, pentaerythritol, and/or sugars); and reaction products of certain aldehydes with certain phenols; and combinations of these reaction products.

Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, composition of matter, and/or user interface adapted for and/or resulting from, and/or a method and/or machine-readable medium comprising machine-implementable instructions for, activities that can comprise and/or relate to, reacting reactants comprising a ferric/ferrous chelate and a sour gas stream.

Methods of producing a treated gas by removing nitrogenous compounds are disclosed. Methods of recovering ammonia from a gas stream having nitrogenous compounds are disclosed. Methods of producing a fertilizer product from organic waste are disclosed. The methods may include introducing aqueous sulfurous acid into a gas stream having nitrogenous compounds to absorb the nitrogenous compounds in a liquid and produce a treated gas. The methods may also include maintaining the pH of certain solutions above 5 or introducing an oxidant into certain solutions to produce sulfate ions. Systems for removing nitrogenous compounds including a reaction subsystem, a solids-liquid separator, a temperature control subsystem, an oxidation control subsystem, and a recirculation line are also disclosed. The systems may be employed to remove nitrogenous compounds from a gas stream, recover the ammonia from the gas stream, or produce a fertilizer product from the recovered ammonia.

A system for removing contaminants from both liquid and gaseous hydrocarbon streams and methods thereof are described. An additive that reacts with said contaminant to form water-soluble compounds is injected into the hydrocarbon streams.

One aspect of the invention relates to a method comprising a single-stage conversion of an atmospheric pollutant, such as NO, NO.sub.2 and/or SO.sub.x in a first stream to one or more mineral acids and/or salts thereof by reacting with nonionic gas phase chlorine dioxide (ClO.sub.2.sup.0), wherein the reaction is carried out in the gas phase. Another aspect of the invention relates to a method comprising first adjusting the atmospheric pollutant concentrations in a first stream to a molar ratio of about 1:1, and then reacting with an aqueous metal hydroxide solution (MOH). Another aspect of the invention relates to an apparatus that can be used to carry out the methods disclosed herein. The methods disclosed herein are unexpectedly efficient and cost effective, and can be applied to a stream comprising high concentration and large volume of atmospheric pollutants.

The invention present provides a method (and suitable apparatus) to convert biomass to ethanol, comprising gasifying the biomass to produce raw syngas; feeding the raw syngas to an acid-gas removal unit to remove at least some CO.sub.2 and produce a conditioned syngas stream; feeding the conditioned syngas stream to a fermentor to biologically convert the syngas to ethanol; capturing a tail gas from an exit of the fermentor, wherein the tail gas comprises at least CO.sub.2 and unconverted CO or H.sub.2; and recycling a first portion of the tail gas to the fermentor and/or a second portion of the tail gas to the acid-gas removal unit. This invention allows for increased syngas conversion to ethanol, improved process efficiency, and better overall biorefinery economics for conversion of biomass to ethanol.

A process and an apparatus for gas denitration, involving first the use of an oxidizing agent to oxidize NO in a gas to NO.sub.2, then using a denitration agent to absorb the NO.sub.2 in the gas, thus achieving the purpose of denitration.

An oxygen-absorbing resin composition including a base resin (A) which is a thermoplastic resin, an oxygen-absorbing component (B) which is a compound having an unsaturated alicyclic structure, and an oxidation promotion component (C) for promoting the oxidation of the oxygen-absorbing component (B); wherein the oxygen-absorbing component (B) is an imide compound having a molecular weight of not more than 2,000 and obtained by heat-treating an amide having been obtained by reacting an acid anhydride represented by the following formula (1): ##STR00001##
wherein the ring X is an alicyclic ring having an unsaturated bond, and Y is an alkyl group, with an aromatic amine, and wherein the oxidation promotion component (C) is a compound having a benzyl hydrogen.