An environment control system utilizes oxygen and humidity control devices that are coupled with an enclosure to independently control the oxygen concentration and the humidity level within the enclosure. An oxygen depletion device may be an oxygen depletion electrolyzer cell that reacts with oxygen within the cell and produces water through electrochemical reactions. A desiccating device may be g, a dehumidification electrolyzer cell, a desiccator, a membrane desiccator or a condenser. A controller may control the amount of voltage and/or current provided to the oxygen depletion electrolyzer cell and therefore the rate of oxygen reduction and may control the amount of voltage and/or current provided to the dehumidification electrolyzer cell and therefore the rate of humidity reduction. The oxygen level may be determined by the measurement of voltage and a limiting current of the oxygen depletion electrolyzer cell. The enclosure may be a food or artifact enclosure.

The invention relates to a process for preparing ammonia gas and CO.sub.2 for urea synthesis. In the process of the invention, a process gas containing nitrogen, hydrogen and carbon dioxide as main components is produced from a metallurgical gas. The metallurgical gas consists of blast furnace gas, or contains blast furnace gas at least as a mixing component. The process gas is fractionated to give a gas stream containing the CO.sub.2 component and a gas mixture consisting primarily of N.sub.2 and H.sub.2. An ammonia gas suitable for the urea synthesis is produced from the gas mixture by means of ammonia synthesis. CO.sub.2 is branched off from the CO.sub.2-containing gas stream in a purity and amount suitable for the urea synthesis.

Applying a sufficient quantity of an Alkali metal or an Alkaline earth metal to a fluid in a stripping process loop 106 to form a first intermediary compound and thereby, to strip the undesired element from the process fluid 102. The first intermediary compound 130 is processed in a recovery process loop 110 to recover the Alkali metal or Alkaline earth metal. The recovered Alkali metal or Alkaline earth metal is then re-introduced to an additional quantity of process fluid to strip and clean the undesired element from the additional quantity of the process fluid. A recovery process loop 110 may include either or both of a chemical substitution process, and an electrolytic process, effective to separate the Alkali metal or Alkaline earth metal from the undesired element or another compound.

A method of treating a carbon dioxide rich flue gas and a flue gas treatment system for treatment of a carbon dioxide rich flue gas are provided. A boiler system includes a boiler, being operative for combusting a fuel and generating a carbon dioxide rich flue gas, and the flue gas treatment system. The flue gas treatment system includes a gas cleaning system, a nitrogen oxides reduction unit, being operative for reducing at least a portion of a nitrogen oxide(s) content of the flue gas, and a compression and cooling device being operative for pressurizing and cooling at least a portion of the flue gas treated by the gas cleaning system and the nitrogen oxide(s) reduction unit.

Provided are a waste gas processing device, a vacuum coating system, and an operation method of a waste gas processing device. The waste gas processing device is configured to remove and recover arsenic in waste gas, and includes a condensation portion and a scraping portion. The condensation portion is provided with a condensation cavity, and an air inlet, an air outlet and a discharge port communicated with the condensation cavity. The condensation portion is configured to cool waste gas charged into the condensation cavity from the air inlet, so that gaseous arsenic in the waste gas is condensed on an inner wall surface of the condensation cavity by cooling to form solid arsenic. The scraping portion is rotatably provided in the condensation cavity, and a partial surface of the scraping portion abuts against the inner wall surface of the condensation cavity.

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.

Methods and systems for producing aromatics and light olefins from a mixed plastics stream are described. The method may include feeding a plastic feedstock to a dechlorination operation to melt the plastic feedstock to release HCl and generate a liquid plastic stream; feeding the liquid plastic stream to a pyrolysis reactor, the pyrolysis reactor to generate hydrocarbon vapors; feeding the hydrocarbon vapors to an acid gas removal reactor with a solid inorganic alkali salt disposed within the reaction vessel to remove residual HCl and sulfur-containing compounds from the hydrocarbon vapors to generate a plastic derived oil; and feeding the plastic derived oil to a fluid catalytic cracking reactor to generate a product stream comprising light olefins having a carbon number of C.sub.2-C.sub.4 and aromatics. The associated system for processing mixed plastics into aromatics and light olefins is also described.

A system and method for recovering high-quality biomethane (RNG) from biogas sources is provided. The gas stream is compressed and liquids are separated from the gas stream at elevated pressure and reduced temperature. The compressing is performed using a plurality of compressors operating in parallel with common control set points. The system and method improve upon conventional practices and yield a biomethane product which meets strict gas pipeline quality specifications. Additionally, the system and method are an improvement to the overall methane recovery efficiency for biogas processing facilities.

A system and method for recovering high-quality biomethane (RNG) from biogas sources are provided. The system and method improve upon conventional practices and yield a biomethane product which meets strict gas pipeline quality specifications. An online sample is captured of a gas stream in near real-time at a pressure swing adsorption vessel, and the online sample is analyzed to detect the presence of one or more targeted products such as CH.sub.4, CO.sub.2 or N.sub.2. The system and method are an improvement to the overall methane recovery efficiency for biogas processing facilities, specifically with regard to PSA control to prevent over or under saturation of the PSA media.

Disclosed are metal organic frameworks (MOFs) for adsorbing guest species, methods for the separation of gases using the MOFs, and systems comprising the MOFs. The MOFs comprise a plurality of secondary building units (SBUs), each SBU comprising a repeating unit of one metal cation connected to another metal cation via a first moiety of an organic linker; a layer of connected adjacent SBUs in which a second moiety of the linker in a first SBU is connected to a metal cation of an adjacent SBU, and wherein adjacent layers are connected to each other via linker-to-linker bonding interactions.