A process for membrane separation of a mixture containing as main, or even major, components hydrogen and carbon dioxide and also at least one other component, for example chosen from the following group: carbon monoxide, methane and nitrogen, including: heating of the mixture in the heat exchanger, permeation of the reheated mixture in a first membrane separation unit making it possible to obtain a first permeate which is a hydrogen and carbon dioxide enriched relative to the mixture, and a first residue which is hydrogen and carbon dioxide lean, permeation of the first residue in a second membrane separation unit making it possible to obtain a second residue, at least one portion of the first permeate is compressed in a booster compressor and the second residue is expanded in a turbine, the booster compressor being driven by the turbine.

A circular carbon process involves: a) reacting hydrogen and carbon monoxide to produce methane and water, b) decomposing methane into carbon and hydrogen, and c) using carbon as reducing agent and/or using carbon in a carbon-containing material as reducing agent, in a chemical process to produce carbon monoxide and a reduced substance. The methane produced in a) is used in b), the carbon produced in b) is used in c), and carbon monoxide produced in c) is used in a).

A circular carbon process involves: a) reacting hydrogen and carbon monoxide to produce methane and water, b) decomposing methane into carbon and hydrogen, and c) using carbon as reducing agent and/or using carbon in a carbon-containing material as reducing agent, in a chemical process to produce carbon monoxide and a reduced substance. The methane produced in a) is used in b), the carbon produced in b) is used in c), and carbon monoxide produced in c) is used in a).

Method and plant for generating a synthesis gas which consists mainly of carbon monoxide and hydrogen and has been freed of acid gases, proceeding from a hydrocarbonaceous fuel, and air and steam, wherein low-temperature fractionation separates air into an oxygen stream, a tail gas stream and a nitrogen stream, wherein the tail gas stream and the nitrogen stream are at ambient temperature and the nitrogen stream is at elevated pressure, wherein the hydrocarbonaceous fuel, having been mixed with the oxygen stream and steam at elevated temperature and elevated pressure, is converted to a synthesis gas by a method known to those skilled in the art, and wherein acid gas is subsequently separated therefrom by low-temperature absorption in an absorption column, wherein the nitrogen stream generated in the fractionation of air is passed through and simultaneously cooled in an expansion turbine and then used to cool either the absorbent or the coolant circulating in the coolant circuit of the compression refrigeration plant.

Method and plant for generating a synthesis gas which consists mainly of carbon monoxide and hydrogen and has been freed of acid gases, proceeding from a hydrocarbonaceous fuel, and air and steam, wherein low-temperature fractionation separates air into an oxygen stream, a tail gas stream and a nitrogen stream, wherein the tail gas stream and the nitrogen stream are at ambient temperature and the nitrogen stream is at elevated pressure, wherein the hydrocarbonaceous fuel, having been mixed with the oxygen stream and steam at elevated temperature and elevated pressure, is converted to a synthesis gas by a method known to those skilled in the art, and wherein acid gas is subsequently separated therefrom by low-temperature absorption in an absorption column, wherein the nitrogen stream generated in the fractionation of air is passed through and simultaneously cooled in an expansion turbine and then used to cool either the absorbent or the coolant circulating in the coolant circuit of the compression refrigeration plant.

Provided is a method for preparing synthesis gas and aromatic hydrocarbons, and more particularly, a method for preparing synthesis gas and aromatic hydrocarbons including: supplying a pyrolysis fuel oil (PFO) stream containing PFO and a pyrolysis gas oil (PGO) stream containing PGO to a distillation tower as a feed stream (S10), the PFO stream and the PGO stream being discharged in a naphtha cracking center (NCC) process; and supplying a lower discharge stream from the distillation tower to a combustion chamber for a gasification process and supplying an upper discharge stream from the distillation tower to a BTX preparation process (S20).

Provided is a method for preparing synthesis gas and aromatic hydrocarbons, and more particularly, a method for preparing synthesis gas and aromatic hydrocarbons including: supplying a pyrolysis fuel oil (PFO) stream containing PFO and a pyrolysis gas oil (PGO) stream containing PGO to a distillation tower as a feed stream (S10), the PFO stream and the PGO stream being discharged in a naphtha cracking center (NCC) process; and supplying a lower discharge stream from the distillation tower to a combustion chamber for a gasification process and supplying an upper discharge stream from the distillation tower to a BTX preparation process (S20).

A method can be employed to regulate and stably operate a steam reforming system that is operated by steam reforming, that has a capacity utilization level that can be regulated, and that comprises a steam reformer, a hydrogenating and desulfurizing unit that is positioned upstream of the steam reformer and is configured for feedstock desulfurization, and a firing unit of the steam reformer. According to the method, a mandated capacity utilization level for the steam reforming system is established with automated regulation of the following continuously monitored parameter ratios: a hydrogen-to-feedstock ratio in the hydrogenating and desulfurizing unit, a steam-to-carbon ratio in the steam reformer, and a fuel-to-air ratio in the firing unit of the steam reformer.

A method can be employed to regulate and stably operate a steam reforming system that is operated by steam reforming, that has a capacity utilization level that can be regulated, and that comprises a steam reformer, a hydrogenating and desulfurizing unit that is positioned upstream of the steam reformer and is configured for feedstock desulfurization, and a firing unit of the steam reformer. According to the method, a mandated capacity utilization level for the steam reforming system is established with automated regulation of the following continuously monitored parameter ratios: a hydrogen-to-feedstock ratio in the hydrogenating and desulfurizing unit, a steam-to-carbon ratio in the steam reformer, and a fuel-to-air ratio in the firing unit of the steam reformer.

A plant complex may include a unit that produces CO.sub.2-containing gases, a gas conducting system for CO.sub.2-containing gases, a gas/liquid separation system, a reformer that is connected to the gas conducting system and where the CO.sub.2-containing gas reacts with H.sub.2 and/or hydrocarbons to give a CO— and H.sub.2-containing synthesis gas mixture. The reformer is connected to a reactor for producing higher alcohols in which the synthesis gas mixture reacts with H.sub.2 to give a gas/liquid mixture containing higher alcohols. For separating off the alcohols of the gas/liquid mixture, the gas/liquid separation system is connected to the reactor for producing higher alcohols.