Systems and methods are provided for performing hydrocarbon reforming within a reverse flow reactor environment (or another reactor environment with flows in opposing directions) while improving management of CO.sub.2 generated during operation of the reactor. The improved management of CO.sub.2 is achieved by making one or more changes to the operation of the reverse flow reactor. The changes can include using an air separation unit to provide an oxygen source with a reduced or minimized content of nitrogen and/or operating the reactor at elevated pressure during the regeneration stage. By operating the regeneration at elevated pressure, a regeneration flue gas can be generated that is enriched in CO.sub.2 at elevated pressure. The CO.sub.2-enriched stream can include primarily water as a contaminant, which can be removed by cooling while substantially maintaining the pressure of the stream. This can facilitate subsequent recovery and use of the CO.sub.2.

A substantially linear ceramic or metallic radiant of ellipsoidal or polygonal cross section is placed proximate furnace tubes or coils in the radiant section of a fired heater to increase the radiant heat directed to the surface of the tubes or coils.

A fuel cell system includes at least one of plural electrochemical pump separators to separate carbon dioxide from a fuel exhaust stream or a combination of a gas separator and a fuel exhaust cooler located outside a hotbox.

A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.

Configurations and related processing schemes of direct or indirect inter-plants heating systems (or both) synthesized for grassroots medium grade crude oil semi-conversion refineries to increase energy efficiency from specific portions of low grade waste heat sources are described. Configurations and related processing schemes of direct or indirect inter-plants heating systems (or both) synthesized for integrated medium grade crude oil semi-conversion refineries and aromatics complex for increasing energy efficiency from specific portions of low grade waste sources are also described.

The present disclosure is directed to the integration of direct air capture of carbon dioxide with thermochemical water splitting, the latter optionally driven by solar energy. The disclosure is also directed to a process comprising extracting carbon dioxide from an air stream by contacting the air-stream with an alkali metal ion-transition metal oxide of empirical formula A.sub.xMO.sub.2 (0.1<x1), where A represents the alkali metal ion comprising sodium ion, potassium ion, or a combination thereof and M comprises iron, manganese, or a combination thereof to form a transition metal composition comprising an oxidized ion extracted-transition metal oxide.

Methods and systems for producing hydrogen substantially without greenhouse gas emissions, the method including producing a product gas comprising hydrogen and carbon dioxide from a hydrocarbon fuel source; separating hydrogen from the product gas to create a hydrogen product stream and a byproduct stream; injecting the byproduct stream into a reservoir containing mafic rock; and allowing components of the byproduct stream to react in situ with components of the mafic rock to precipitate and store components of the byproduct stream in the reservoir.

Systems and methods are provided for using a high heat capacity gas as at least a portion of the diluent during the regeneration step of a reverse flow reactor process. Instead of using nitrogen or air as the primary diluent gas, CO.sub.2 and/or H.sub.2O can be added as diluent gas for the regeneration step in the reaction cycle. Increasing the heat capacity of the diluent gas provides a reduction in the peak temperature within the reactor relative to the amount of fuel combusted during regeneration. This can allow for a reduction in the volume of diluent used during regeneration and/or an increase in the amount of fuel used. Reducing the volume of diluent can reduce the pressure drop during regeneration, which can provide a corresponding reduction in the amount of compression required for recycle of the diluent. Increasing the amount of fuel can allow for a corresponding increase in the amount of endothermic reaction performed during the reaction step.

Methods and systems for gas separation of syngas applying differences in water solubilities of syngas components, the method including producing a product gas comprising hydrogen and carbon dioxide from a hydrocarbon fuel source; separating hydrogen from the product gas to create a hydrogen product stream and a byproduct stream by solubilizing components in water that are more soluble in water than hydrogen; injecting the byproduct stream into a reservoir containing mafic rock; and allowing components of the byproduct stream to react in situ with components of the mafic rock to precipitate and store components of the byproduct stream in the reservoir.

The present disclosure generally relates to systems and methods for the combustive abatement of waste gas formed during the manufacture of semiconductor wafers. In particular, the systems described herein are capable of combusting air-polluting perfluorocarbons, including those having high greenhouse gas indexes such as hexafluoroethane (C.sub.2F.sub.6) and tetrafluoromethane (CF.sub.4), as well as particulate-forming silicon dioxide precursors, such as silane (SiH.sub.4) and tetraethoxysilane (Si(OC.sub.2H.sub.5).sub.4, abbreviated TEOS), with greater efficiency and lower energy usage than prior abatement systems. More particularly, and in one preferred embodiment, the present disclosure is directed to a waste gas abatement system that utilizes a combination of non-combustible and combustible gases (or gas mixtures) for thermal combustion, which are directed through multiple permeable interior surfaces of a reaction chamber, efficiently combusting waste gas and preventing undesirable accumulation of solid particulate matter on the chamber surfaces.