Systems and methods are provided for improving the operation of groups of reverse flow reactors by operating reactors in a regeneration portion of the reaction cycle to have improved flue gas management. The flue gas from reactor(s) at a later portion of the regeneration step can be selectively used for recycle back to the reactors as a diluent/heat transport fluid. The flue gas from a reactor earlier in a regeneration step can be preferentially used as the gas vented from the system to maintain the desired volume of gas within the system. This results in preferential use of higher temperature flue gas for recycle and lower temperature flue gas for venting from the system. This improved use of flue gas within a reaction system including reverse flow reactors can allow for improved reaction performance while reducing or minimizing heat losses during the regeneration portion of the reaction cycle.

Systems and methods are provided for improving the operation of groups of reverse flow reactors by operating reactors in a regeneration portion of the reaction cycle to have improved flue gas management. The flue gas from reactor(s) at a later portion of the regeneration step can be selectively used for recycle back to the reactors as a diluent/heat transport fluid. The flue gas from a reactor earlier in a regeneration step can be preferentially used as the gas vented from the system to maintain the desired volume of gas within the system. This results in preferential use of higher temperature flue gas for recycle and lower temperature flue gas for venting from the system. This improved use of flue gas within a reaction system including reverse flow reactors can allow for improved reaction performance while reducing or minimizing heat losses during the regeneration portion of the reaction cycle.

Systems and methods are provided for hydrogenation of CO.sub.2 in a reverse flow reactor environment via a reverse water gas shift reaction. A reverse flow reactor environment is suitable for performing endothermic reactions at high temperatures, where a reactant flow is passed into the reactor in a first portion of the cycle in a first flow direction while a combustion or heating flow is passed into the reactor during a second portion of the reaction cycle from the opposite direction. This can allow for efficient heating of surfaces within the reactor to provide heat for the endothermic reverse water gas shift reaction while reducing or minimizing incorporation of combustion products into the desired reaction products.

An integrated reformer includes an outer chamber, a first inlet, a second inlet, and a cooling unit associated with the outer chamber. The first inlet is configured to obtain a first gas stream into a first space in the outer chamber. The second inlet is configured to obtain a second gas stream into the first space in the outer chamber. The cooling unit is configured to absorb thermal energy from the first gas stream.

Reactors are provided that can include a first set of fluid channels and a second set of fluid channels oriented in thermal contact with the first set of fluid channels. The reactor assemblies can also provide where the channels of either one or both of the first of the set of fluid channels are non-linear. Other implementations provide for at least one of the first set of fluid channels being in thermal contact with a plurality of other channels of the second set of fluid channels. Reactor assemblies are also provided that can include a first set of fluid channels defining at least one non-linear channel having a positive function, and a second set of fluid channels defining at least another non-linear channel having a negative function in relation to the positive function of the one non-linear channel of the first set of fluid channels. Processes for distributing energy across a reactor are provided. The processes can include transporting reactants via a first set of fluid channels to a second set of fluid channels, and thermally engaging at least one of the first set of fluid channels with at least two of the second set of fluid channels.

Reactors are provided that can include a first set of fluid channels and a second set of fluid channels oriented in thermal contact with the first set of fluid channels. The reactor assemblies can also provide where the channels of either one or both of the first of the set of fluid channels are non-linear. Other implementations provide for at least one of the first set of fluid channels being in thermal contact with a plurality of other channels of the second set of fluid channels. Reactor assemblies are also provided that can include a first set of fluid channels defining at least one non-linear channel having a positive function, and a second set of fluid channels defining at least another non-linear channel having a negative function in relation to the positive function of the one non-linear channel of the first set of fluid channels. Processes for distributing energy across a reactor are provided. The processes can include transporting reactants via a first set of fluid channels to a second set of fluid channels, and thermally engaging at least one of the first set of fluid channels with at least two of the second set of fluid channels.

A fuel cell system includes a fuel cell stack, a fuel inlet conduit configured to provide a fuel to a fuel inlet of the fuel cell stack, an electrochemical pump separator containing an electrolyte, a cathode, and a carbon monoxide tolerant anode, a fuel exhaust conduit that operatively connects a fuel exhaust outlet of the fuel cell stack to an anode inlet of the electrochemical pump separator, and a product conduit which operatively connects a cathode outlet of the electrochemical pump separator to the fuel inlet conduit.

A fuel cell system includes a fuel cell stack, a fuel inlet conduit configured to provide a fuel to a fuel inlet of the fuel cell stack, an electrochemical pump separator containing an electrolyte, a cathode, and a carbon monoxide tolerant anode, a fuel exhaust conduit that operatively connects a fuel exhaust outlet of the fuel cell stack to an anode inlet of the electrochemical pump separator, and a product conduit which operatively connects a cathode outlet of the electrochemical pump separator to the fuel inlet conduit.

Hydrogen generation assemblies, hydrogen purification devices, and their components, and methods of manufacturing those assemblies, devices, and components are disclosed. In some embodiments, the devices may include an insulation base having insulating material and at least one passage that extends through the insulating material. In some embodiments, the at least one passage may be in fluid communication with a combustion region.

A method of improving an endothermic process in a furnace utilizing steps a) calibrating the simplified physical model of step c3) by measuring one or more tube temperature for at least a tube impacted by the throttling of a burner in standard and in throttled state, b) acquiring information on a tube temperature for the tubes present in the furnace with all the burners present in the furnace under standard non-throttled conditions, c) getting a map of burners to throttle including c1) choosing at least one parameter representative of the performances of the furnace with a target of improvement, c2) choosing at least one or more power ratio for the burner throttling; c3) utilizing the information of step b) and a simplified physical model of the impact of throttling a burner on the tube temperature, c4) getting a map of burners to throttle, step d) throttling the burners.