Disclosed are methods of using a hot oxygen generator to respond to changes in the characteristic of the feed to a partial oxidation reactor.

The invention provides a process for producing a fermentable gas stream from a gas source that contains one or more constituent which may be harmful to the fermentation process. To produce the fermentable gas stream, the gas stream is passed through a specifically ordered series of removal modules. The removal modules remove and/or convert various constituents found in the gas stream which may have harmful effects on downstream removal modules and/or inhibitory effects on downstream gas fermenting microorganisms. At least a portion of the fermentable gas stream is preferably capable of being passed to a bioreactor, which contains gas fermenting microorganisms, without inhibiting the fermentation process.

Acid gas compounds are removed from a process gas such as, for example, syngas or natural gas, by flowing a feed gas into a desulfurization unit to remove a substantial fraction of sulfur compounds from the feed gas and flowing the resulting desulfurized gas into a CO.sub.2 removal unit to remove a substantial fraction of CO.sub.2 from the desulfurized gas.

The invention is directed to a process for the preparation of a syngas comprising hydrogen and carbon monoxide from a methane comprising gas, which process comprises the steps of: (a) reacting the methane comprising gas with an oxidising gas in an autothermal reformer to obtain a hot raw syngas comprising carbon monoxide and hydrogen; (b) cooling the hot raw syngas resulting from step (a) to obtain the syngas, wherein step (b) comprises cooling the hot raw syngas by indirect heat exchange against the methane comprising gas used in step (a) and wherein sulphur is added upstream of cooling step (b). The invention also relates to a process for the preparation of hydrocarbon products in which a feed syngas is prepared in the process as described above followed by a desulphurisation treatment and the desulphurised syngas is subsequently converted into hydrocarbon products in a Fischer-Tropsch process.

A process for the manufacture of a useful product from carbonaceous feedstock of fluctuating compositional characteristics, comprising the steps of: continuously providing the carbonaceous feedstock of fluctuating compositional characteristics to a gasification zone; gasifying the carbonaceous feedstock in the gasification zone to obtain raw synthesis gas; recovering at least part of the raw synthesis gas from the gasification zone and supplying at least part of the recovered raw synthesis gas to a partial oxidation zone; equilibrating the H.sub.2:CO ratio of the raw synthesis gas in the partial oxidation zone to obtain equilibrated synthesis gas; recovering at least part of the equilibrated synthesis gas from the partial oxidation zone and treating the gas to remove impurities and generate a fine synthesis gas; and converting the optionally adjusted fine synthesis gas into the useful product in a further chemical reaction requiring a usage ratio.

A SOFC system for producing a refined carbon dioxide product, electrical power, and a compressed hydrogen product is presented. The system can include a hydrodesulfurization system, a steam reformer, a water-gas shift reactor system, a hydrogen purification system, a hydrogen compression and storage system, a pre-reformer, and a CO2 purification and liquidification system.

The invention relates to a method of selectively removing hydrogen sulfide H.sub.2S from a gaseous effluent comprising at least H.sub.2S and CO.sub.2, wherein a stage of selective absorption of hydrogen sulfide over CO.sub.2 is carried out by contacting said effluent with a solution comprising (a) water and (b) at least the following diamine: 1,2-bis(2-dimethylaminoethoxy)ethane ##STR00001##
and wherein the absorption selectivity is controlled by adding (c) a viscosifying compound to the absorbent solution.

Proposed are a process and a plant for producing a synthesis gas product stream having an adjustable H.sub.2/CO ratio and a pure hydrogen stream, wherein it is provided according to the invention that a substream of a deacidified synthesis gas stream is supplied to a membrane separation plant fitted with a hydrogen-selective membrane and the remaining substream is supplied to a pressure swing adsorption plant, wherein the latter affords a pure hydrogen stream and a fuel gas stream. The hydrogen-enriched permeate stream obtained from the membrane separation is likewise supplied to the pressure swing adsorption plant, thus enhancing the yield of pure hydrogen. The hydrogen-depleted retentate stream obtained from the membrane separation is discharged as a synthesis gas product stream and if of a suitable composition may be utilized as oxo gas.

A process and system for treating a hydroprocessing unit effluent gas stream for recycling includes introducing the effluent gas stream into a hydrogen purification zone and recovering a hydrogen-rich gas stream and a liquid stream containing a mixture that includes C1 to C4 hydrocarbons and H.sub.2S which is then mixed with an oxidant and fed to an oxidation unit containing catalyst for conversion of the H.sub.2S to elemental sulfur vapors that is separated for recovery of the elemental sulfur, and recovering a sweetened mixture that includes C1 to C4 hydrocarbons. Alternatively, the hydroprocessing unit effluent gas stream containing H.sub.2S is cooled, contacted with a solvent to absorb the C1 to C4 hydrocarbons and H.sub.2S, with the hydrogen-rich stream being recovered for recycling to the hydroprocessing unit, and the rich liquid solvent being flashed to produce a lean solvent stream for recycling to the adsorption zone and a mixed gas stream that includes the C1 to C4 hydrocarbons and H.sub.2S that is passed to an oxidation zone and is reacted with an oxidant in the presence of a catalyst to complete the process as described above for the recovery of elemental sulfur and a mixture that includes the sweetened C1 to C4 hydrocarbons.

Generation of bubbles in an organic-substance production apparatus is suppressed. A gas treatment method including: an adsorption step of passing a source gas containing at least carbon dioxide and nitrogen through an adsorption unit housing an adsorbent for adsorbing carbon dioxide to reduce a carbon dioxide concentration in the source gas; a supply step of supplying the source gas whose carbon dioxide concentration has been reduced by the adsorption step to an organic-substance production apparatus that produces an organic substance; and a monitoring step of monitoring a carbon dioxide concentration and a nitrogen concentration in the source gas before passing through the adsorption unit, a carbon dioxide concentration and a nitrogen concentration in the source gas after having passed through the adsorption unit, or a carbon dioxide concentration and a nitrogen concentration in the source gas having been supplied to the organic-substance production apparatus; wherein the adsorption step has an ability regulation step of enhancing an ability of the adsorption unit to reduce a carbon dioxide concentration in the source gas, when a total concentration of the carbon dioxide concentration and the nitrogen concentration monitored in the monitoring step exceeds a threshold value.