Organic sulfur compounds contained in refinery off gas streams having either high ort low concentrations of olefins are converted to hydrogen sulfides which can be then be removed using conventional amine treating systems. The process uses a catalytic reactor with or without a hydrotreater depending on the olefin concentration of the off gas stream. The catalytic reactor operates in a hydrogenation mode or an oxidation mode to convert a majority of organic sulfur compounds into hydrogen sulfides.

The present invention concerns a process for the treatment of a hydrocarbon feed containing hydrogen and hydrocarbons including C.sub.1 to C.sub.4 hydrocarbons, employing a first and a second recontacting step and in which the gaseous effluent obtained from the second recontacting step is recycled to the first recontacting step. The process is of particular application to the treatment of a hydrocarbon feed obtained from catalytic reforming with a view to recovering hydrogen and C.sub.3 and C.sub.4 hydrocarbons.

The present invention concerns a process for the treatment of a hydrocarbon feed containing hydrogen and hydrocarbons including C.sub.1 to C.sub.4 hydrocarbons, employing a first and a second recontacting step and in which the gaseous effluent obtained from the second recontacting step is recycled to the first recontacting step. The process is of particular application to the treatment of a hydrocarbon feed obtained from catalytic reforming with a view to recovering hydrogen and C.sub.3 and C.sub.4 hydrocarbons.

Processes and systems for upgrading a hydrocarbon. In some embodiments, the process for upgrading a hydrocarbon, can include contacting a gas that can include one or more C.sub.1-C.sub.4 hydrocarbons and carbonyl sulfide with a sorbent under conditions sufficient to cause at least a portion of the carbonyl sulfide to sorb onto the sorbent to produce a treated gas lean in carbonyl sulfide and a sorbent rich in carbonyl sulfide. The process can also include contacting the sorbent rich in carbonyl sulfide with a regenerating gas that can include molecular hydrogen, one or more C.sub.1-C.sub.4 hydrocarbons, or a mixture thereof to produce a regenerated sorbent and a desorb effluent that can include a sulfur-based contaminant. The process can also include introducing at least a portion of the desorb effluent into a pyrolysis zone of a steam cracker and recovering a steam cracker effluent from the pyrolysis zone.

Processes and systems for upgrading a hydrocarbon. In some embodiments, the process for upgrading a hydrocarbon, can include contacting a gas that can include one or more C.sub.1-C.sub.4 hydrocarbons and carbonyl sulfide with a sorbent under conditions sufficient to cause at least a portion of the carbonyl sulfide to sorb onto the sorbent to produce a treated gas lean in carbonyl sulfide and a sorbent rich in carbonyl sulfide. The process can also include contacting the sorbent rich in carbonyl sulfide with a regenerating gas that can include molecular hydrogen, one or more C.sub.1-C.sub.4 hydrocarbons, or a mixture thereof to produce a regenerated sorbent and a desorb effluent that can include a sulfur-based contaminant. The process can also include introducing at least a portion of the desorb effluent into a pyrolysis zone of a steam cracker and recovering a steam cracker effluent from the pyrolysis zone.

A method and apparatus for continuously treating acid gases including recovering absorbent chemicals by introducing streams leaving a regenerator and/or leaving an absorber into a static mixing zone wherein supplemental washing water is added to recover absorbent chemicals. Improvements to the prior art methods are provided where one or more absorbent chemical recovery units are included to increase the amount of recovered absorbent chemicals exiting the regenerator and/or exiting the absorber are increased and/or maximized. Absorbent chemical recovery units can include mixing units where liquid is added to the stream of sour gas and absorbent chemical to mix with and absorb the absorbent chemical from the stream.

A method and apparatus for continuously treating acid gases including recovering absorbent chemicals by introducing streams leaving a regenerator and/or leaving an absorber into a static mixing zone wherein supplemental washing water is added to recover absorbent chemicals. Improvements to the prior art methods are provided where one or more absorbent chemical recovery units are included to increase the amount of recovered absorbent chemicals exiting the regenerator and/or exiting the absorber are increased and/or maximized. Absorbent chemical recovery units can include mixing units where liquid is added to the stream of sour gas and absorbent chemical to mix with and absorb the absorbent chemical from the stream.

A method for recovering C2 components in a methane-containing industrial gas includes the steps of (1) cooling a compressed methane-containing industrial gas and performing gas-liquid separation; (2) absorbing C2 components in the gas phase by using an absorbent to obtain an absorption rich liquid; (3) returning the absorption rich liquid to the compression in step (1) or mixing the absorption rich liquid with the liquid phase obtained in step (1) to obtain a mixed liquid, and depressurizing the mixed liquid or the absorption rich liquid; (4) performing methane desorption on the depressurized stream to obtain a rich absorbent, or performing second gas-liquid separation on the depressurized stream, followed by methane desorption on the second liquid phase to obtain a rich absorbent; and (5) desorbing and separating the rich absorbent to obtain a lean absorbent and an enriched gas, and recycling and reusing the lean absorbent.

A method for recovering C2 components in a methane-containing industrial gas includes the steps of (1) cooling a compressed methane-containing industrial gas and performing gas-liquid separation; (2) absorbing C2 components in the gas phase by using an absorbent to obtain an absorption rich liquid; (3) returning the absorption rich liquid to the compression in step (1) or mixing the absorption rich liquid with the liquid phase obtained in step (1) to obtain a mixed liquid, and depressurizing the mixed liquid or the absorption rich liquid; (4) performing methane desorption on the depressurized stream to obtain a rich absorbent, or performing second gas-liquid separation on the depressurized stream, followed by methane desorption on the second liquid phase to obtain a rich absorbent; and (5) desorbing and separating the rich absorbent to obtain a lean absorbent and an enriched gas, and recycling and reusing the lean absorbent.

Process for hydrotreatment of hydrocarbon-containing feedstock comprising sulphur- and nitrogen-containing compounds, comprising: a) separating the feedstock into heavy and light fractions, b) a first hydrotreatment stage wherein the heavy fraction and hydrogen are contacted with a first hydrotreatment catalyst Z1 to produce a first desulphurized effluent, c) separating the first effluent into a first gaseous fraction and a first liquid fraction, d) purifying the first gaseous fraction to produce a hydrogen-rich flow, e) mixing the light fraction with the first liquid fraction to produce a mixture, f) a second hydrotreatment stage wherein the mixture from stage e) and the hydrogen-rich flow from stage d) are contacted with a second hydrotreatment catalyst Z2 to produce a second desulphurized effluent, g) separating the second effluent into a second gaseous fraction and a second liquid fraction, h) recycling at least part of the second gaseous fraction to b) as a flow of hydrogen.