Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

Improved processes and systems are disclosed for producing renewable hydrogen suitable for reducing metal ores, as well as for producing activated carbon. Some variations provide a process comprising: pyrolyzing biomass to generate a biogenic reagent comprising carbon and a pyrolysis off-gas; converting the pyrolysis off-gas to additional reducing gas and/or heat; reacting at least some of the biogenic reagent with a reactant to generate a reducing gas; and chemically reducing a metal oxide in the presence of the reducing gas. Some variations provide a process for producing renewable hydrogen by biomass pyrolysis to generate a biogenic reagent, conversion of the biogenic reagent to a reducing gas, and separation and recovery of hydrogen from the reducing gas. A reducing-gas composition for reducing a metal oxide is provided, comprising renewable hydrogen according to a hydrogen-isotope analysis. Reacted biogenic reagent may also be recovered as an activated carbon product. Many variations are disclosed.

The present disclosure relates to systems and methods useful for providing one or more chemical compounds in a substantially pure form. In particular, the systems and methods can be configured for separation of carbon dioxide from a process stream, such as a process stream in a hydrogen production system. As such, the present disclosure can provide systems and method for production of hydrogen and/or carbon dioxide.

The present invention relates to a cold box cycle which allows for independent control of the heat supplied for reboilers associated with the separation columns. More specifically, the invention relates to the tight control of the hydrogen removal separation, thus avoiding the possibility of excess reboiling in this separation. Optimal reboiling also results in a lower temperature of the hydrogen depleted liquid from this separation. As this stream is used to provide a portion of the cooling at the cold end of the primary heat exchanger, lower temperatures facilitate cooling of the incoming syngas feed, reducing carbon monoxide (CO) losses into the crude hydrogen stream from the high pressure separator. Lower CO in the crude hydrogen allows for smaller hydrogen purification equipment.

The invention relates to a method (100) for the recovery of a separation product which contains predominantly hydrocarbons with two carbon atoms, with the use of a separation feedstock which contains predominantly methane, hydrogen and hydrocarbons with two carbon atoms, wherein the methane content of the separation feedstock is up to 20%, and the separation feedstock is provided in a gaseous state. It is provided that, at a first pressure level, the separation feedstock is partially condensed in a single step by cooling from a first temperature level to a second temperature level, thereby obtaining precisely one first liquid fraction and precisely one first gaseous fraction; at least one part of the first gaseous fraction is partially condensed in a single step through further cooling from the second temperature level to a third temperature level, thereby obtaining precisely one second liquid fraction and precisely one second gaseous fraction; at least one part of the second gaseous fraction at the second pressure level is subjected to a contraflow absorption in the contraflow to an absorption liquid containing predominantly methane, thereby obtaining precisely one third liquid fraction and precisely one third gaseous fraction; the first, the second and the third liquid fraction are at least partially combined and, at least partially, at a second pressure level above the first pressure level, subjected to a low-temperature rectification, thereby obtaining a sump liquid and an overhead gas; at least one part of the overhead gas at the second pressure level is partially condensed in a single step through further cooling from the second temperature level to the third temperature level, thereby obtaining a fourth liquid fraction and a fourth gaseous fraction; and the absorption liquid containing predominantly methane is formed through further cooling of at least a part of the fourth gaseous fraction to a fourth temperature level. A corresponding plant also forms the subject matter of the invention.

The invention relates to a process and device for the cryogenic separation of a methane-containing feed gas predominantly consisting of hydrogen and carbon monoxide, that is partially condensed in this case by cooling, in order to obtain a hydrogen-containing first liquid phase predominantly consisting of carbon monoxide and methane, from which first liquid phase, in an H.sub.2 separation column that is heated via a circulation heater, a second liquid phase is generated by separating off hydrogen, from which second liquid phase, in a CO/CH.sub.4 separation column, a carbon monoxide-rich gas phase is obtained having a purity that permits release thereof as carbon monoxide product. It is characteristic in this case that a low-methane material stream is withdrawn from the H.sub.2 separation column and is then applied to the CO/CH.sub.4 separation column as reflux.

Proposed is a process and a plant for production of pure carbon monoxide and hydrogen by steam reforming of hydrocarbons, preferably methane or naphtha, to afford a raw synthesis gas and subsequent, multistage workup, purification and fractionation of the raw synthesis gas to afford the target products, wherein the material streams obtained as by-products of the process chain are also to be advantageously utilized. This is achieved according to the invention by providing the recirculating compressor provided for recycling of the by-product material streams with a plurality of parallel, independently operable compressor stages.

The present disclosure relates to systems and methods useful for providing one or more chemical compounds in a substantially pure form. In particular, the systems and methods can be configured for separation of carbon dioxide from a process stream, such as a process stream in a hydrogen production system. As such, the present disclosure can provide systems and method for production of hydrogen and/or carbon dioxide.

The present invention is directed to a method and system of separating carbon monoxide from syngas mixtures with high methane content by cryogenic means where a partial condensation cycle is generally employed, and more specifically towards combining the methane-rich liquid exiting the distillation column with a lower-boiling mixture so that the boiling point of the combined stream is lower than the boiling point of the methane-rich liquid.

The present invention is directed to a method of separating carbon monoxide from syngas mixtures by cryogenic means where a partial condensation cycle is generally employed, and more specifically varying refrigeration generation based on income feed composition of the hydrocarbon feedstock being processed.