The invention relates to a process for the start-up of an autothermal reformer, wherein syngas is produced in the autothermal reformer during start-up through steam reforming. To facilitate autoignition in the autothermal reformer reactor of the autothermal reformer, the reformed syngas is recycled to an upstream section of the autothermal reformer reactor and is mixed with process steam and a hydrocarbon containing process stream. As soon as a minimum hydrogen threshold concentration at the upstream section of the autothermal reformer reactor is reached in the mixed process stream, oxygen is added to the burner of the ATR reactor to obtain autoignition of the mixed process stream. Due to the process of the invention, an external hydrogen source for facilitating autoignition of the mixed stream can be omitted. The invention further relates to a plant configured to carry out the process of the invention.

A plant, such as a hydrocarbon plant, is provided, which has a syngas stage (A) for syngas generation and a synthesis stage (B) where said syngas is synthesized to produce syngas derived product, such as hydrocarbon product. The syngas stage (A) primarily includes electrically heated reverse water gas shift (e-RWGS) section. Additionally, an electrically-heated steam methane reforming (e-SMR) section (II) can be arranged in parallel to the e-RWGS section (I). The plant makes effective use of various streams; in particular CO2 and H2. A method for producing a product stream, such as a hydrocarbon product stream is also provided.

The disclosure relates to methods, systems, and apparatus arranged and designed for converting non-methane hydrocarbon gases into multiple product gas streams including a predominately hydrogen gas stream and a predominately methane gas steam. Hydrocarbon gas streams are reformed, cracked, or converted into a synthesis gas stream and methane gas stream by receiving a volume of flare gas or other hydrocarbon liquid or gas feed, where the volume of hydrocarbon feed includes a volume of methane and a volume of nonmethane hydrocarbons. The hydrogen contained in the syngas may be separated into a pure hydrogen gas stream. A corresponding gas conversion system can include a super heater to provide a hydrocarbon feed/steam mixture, a heavy hydrocarbon reactor for synthesis gas formation, and a hydrogen separator to recover the hydrogen portion of the synthesis gas.

A process for the production of hydrogen comprises: a first steam reforming step of a feedstock containing hydrocarbons to obtain a first synthesis gas; a first synthesis gas shift and cooling step on the first synthesis gas; a separation step for separating the first synthesis gas into a high concentration hydrogen stream and a tail gas stream; a second low pressure steam reforming step performed on the tail gas to obtain a second synthesis gas; a second synthesis gas shift and cooling step on the second synthesis gas; a CO2 removal step performed on the stream of hydrogen and carbon dioxide exiting the second synthesis gas shift and cooling step in order to separate a CO2 stream from a fuel grade hydrogen stream; a step of feeding at least a part of the fuel grade hydrogen stream to the first steam reforming step.

A process and apparatus for producing a hydrogen-enriched product and recovering CO.sub.2 from an effluent stream from a hydrogen production process unit are described. The process utilizes a CO.sub.2 recovery system integrated with a PSA system that produces at least two product streams to recover additional hydrogen and CO.sub.2 from the tail gas stream of a hydrogen PSA unit in the hydrogen production process.

A process and apparatus for producing a hydrogen-enriched product and recovering CO.sub.2 from an effluent stream from a hydrogen production unit are described. The effluent from the hydrogen production unit, which comprises a mixture of gases comprising hydrogen, carbon dioxide, water, and at least one of methane, carbon monoxide, nitrogen, and argon, is sent to a PSA system that produces at least two product streams for separation. The PSA system that produces at least two product streams separates the gas mixture into a high-pressure hydrogen stream enriched in hydrogen, optionally a second gas stream containing the majority of the impurities, and a low-pressure tail gas stream enriched in CO.sub.2 and some impurities. The CO.sub.2-rich tail gas stream is compressed and sent to a CO.sub.2 recovery unit, where a CO.sub.2-enriched stream is recovered. The CO.sub.2-depleted overhead gas stream is recycled to the PSA system that produces at least two product streams.

A syngas stage, for use in a chemical plant, is provided, which includes a methanation section and an autothermal reforming section. The syngas stage makes effective utilization of CO2 rich stream and H2 rich stream. The syngas stage may include an external feed of hydrocarbons. A method for producing a syngas stream is also provided.

The invention includes a gas processing system for transforming a hydrocarbon-containing inflow gas into outflow gas products, where the system includes a gas delivery subsystem, a plasma reaction chamber, and a microwave subsystem, with the gas delivery subsystem in fluid communication with the plasma reaction chamber, so that the gas delivery subsystem directs the hydrocarbon-containing inflow gas into the plasma reaction chamber, and the microwave subsystem directs microwave energy into the plasma reaction chamber to energize the hydrocarbon-containing inflow gas, thereby forming a plasma in the plasma reaction chamber, which plasma effects the transformation of a hydrocarbon in the hydrocarbon-containing inflow gas into the outflow gas products, which comprise acetylene and hydrogen. The invention also includes methods for the use of the gas processing system.

A process for producing and storing hydrogen includes providing an intermediate gas mixture having an increased proportion of hydrogen and contacting of the intermediate gas mixture with a hydrogen carrier medium in order to hydrogenate the hydrogen carrier medium.

A process can be used to treat a synthesis gas stream comprising steam reforming firstly in a primary reformer and subsequently in a secondary reformer. Crude synthesis gas exiting the secondary reformer may be cooled in a steam generator and then further cooled in a steam superheater. The crude synthesis gas stream after exiting the secondary reformer may be split into at least two gas substreams, of which only a first gas substream is fed to the steam generator. A second gas substream may be supplied to the steam superheater, bypassing the steam generator. Only the first gas substream, after flowing through the steam generator, may be subjected to a CO conversion reaction in a first CO conversion reactor before the first gas substream is supplied to the steam superheater.