Process for producing biomethane from a biogas stream including methane, carbon dioxide and at least one impurity chosen from ammonia, volatile organic compounds, water, sulfur-based impurities (H.sub.2S) and siloxanes. A biogas stream is dried, the at least one impurity is at least partially removed by solidification and removal of the impurity. The methane and the carbon dioxide contained in the biogas obtained from the second step are separated so as to produce a biomethane stream and a CO.sub.2 stream.

An absorbent composition having a bismuth material on a support containing at least one of a metal oxide, a metalloid oxide or an activated carbon and methods of making and using the same. The adsorbent composition is usful for adsorbing arsine from a fluid stream.

An inlet assembly for a an abatement burner includes: an inlet conduit operable to convey an effluent gas stream to be treated from an inlet aperture via a bore to an outlet aperture for treatment; and a lance conduit operable to convey a fuel gas from a gas inlet aperture via a gas bore to a gas outlet aperture positioned within the bore for mixing with the effluent gas stream, a cross-sectional area of the gas bore increasing towards the gas outlet aperture. In this way, the expansion caused by the increasing cross-sectional area of the gas bore enhances the mixing of the fuel gas with the effluent gas stream which provides for improved destruction and removal efficiencies (DRE), which enables the inlet assembly to be operated with reduced quantities of fuel gas, while still maintaining required levels of DRE.

A purge gas feeding means, an abatement system comprising such a means and a method of modifying an abatement system to include such a purge gas feeding means is disclosed. The purge gas feeding means comprises a plurality of paths running from an outer perimeter of the purge gas feeding means to an inner surface, the inner surface comprising a purge gas outlet for outputting the purge gas into the abatement system; wherein a cross sectional area of the plurality of paths increases from the outer perimeter to the inner surface such that a pressure of the purge gas falls flowing along the paths drops.

Various embodiments disclosed relate to extraction of target materials using a CZTS sorbent. A method of extracting a target material from a medium includes contacting a copper zinc tin sulfur (CZTS) sorbent with the target material in the medium including the target material to form a used CZTS sorbent that includes the target material. The method also includes separating the used CZTS sorbent from the medium.

An agent for removing a halogen gas, such as chlorine, in a waste gas by means of reduction; a method for producing this agent; a method for removing a halogen gas by use of this agent; and a system for removing a halogen gas. The agent for removing the halogen gas contains at least pseudo-boehmite, that serves as a host material, and a sulfur-containing reducing agent, that serves as a guest material. 1-8% by weight of the reducing agent, in terms of elemental sulfur, based on the total amount of the pseudo-boehmite and sulfur-containing reducing agent is present in the agent. At least one inorganic compound selected from among oxides, carbonates salts and hydrocarbon salts of alkaline earth metal elements, transition metal elements and zinc group elements is additionally contained in the agent as a third component.

Processes for removing arsenic compounds from a feed stream using an adsorbent in disclosed. The process includes contacting a feed stream comprising at least arsenic and sulfur compounds with an adsorbent comprising an low-crystallinity manganese oxide, at least one halide and a binder, to provide a treated effluent substantially free of the arsenic and sulfur compounds.

The present invention relates to a process for trapping silicon compounds in a gaseous or liquid feedstock, comprising bringing the feedstock into contact with a trapping mass with a liquid hourly space velocity LHSV of less than 5 h.sup.1 or a gas hourly space velocity GHSV of less than 500 h.sup.1.

Technologies for combusting hazardous compounds such as chemical warfare agents and related compounds are disclosed. In embodiments, the technologies include systems and methods for combusting such compounds in an internal combustion engine, such as a spark ignition internal combustion engine, a diesel engine, or the like. The technologies described herein further include components for treating an exhaust gas stream produced by combustion of hazardous compounds. In embodiments such components include a scrubber that utilizes a scrubbing media such as soil to removing acid gases from the exhaust stream.

The present invention relates generally to the field of emission control equipment for boilers, heaters, kilns, or other flue gas-, or combustion gas-, generating devices (e.g., those located at power plants, processing plants, etc.) and, in particular to a new and useful method and apparatus for: (i) reducing the levels of one or more gas phase selenium compounds and/or one or more other RCRA metals, or RCRA metal compounds (regardless of whether such other RCRA metals or RCRA metal compounds are in the gas phase or some other phase); (ii) capturing, sequestering and/or controlling one or more gas phase selenium compound and/or one or more other RCRA metals, or RCRA metal compounds (regardless of whether such other RCRA metals or RCRA metal compounds are in the gas phase or some other phase) in a flue gas stream and/or in one or more pieces of emission control technology; and/or (iii) capturing, sequestering and/or controlling one or more gas phase selenium compound and/or one or more other RCRA metals, or RCRA metal compounds (regardless of whether such other RCRA metals or RCRA metal compounds are in the gas phase or some other phase) in a flue gas stream prior to desulfurization and/or in one or more pieces of emission control technology prior to one or more desulfurization units.