Lummus Technology LLC

The present disclosure relates generally to processes and systems for dehydrogenating alkanes. The present disclosure relates specifically to processes and systems for dehydrogenating alkanes that include purging the one or more catalyst beds by flowing therethrough a first purge gas stream having no more than 5 vol % O 2 and in a first pressure reduction reducing the pressure in the dehydrogenation reactor to no more than 0.5 bar.

A method of converting carbon oxides to olefins is provided. The method can include directing a renewable hydrogen feed stream and a carbon oxide feed stream to a methanation reactor to generate an oxidative coupling of methane (OCM) feed stream that includes methane. The OCM feed stream and an oxidant feed stream including oxygen are directed to an OCM reactor containing an OCM catalyst to produce an OCM effluent that includes ethylene. A system for converting carbon oxides to olefins is also provided. The methods and systems produce olefins including ethylene with negative carbon emissions.

A pyrolysis process for converting a hydrocarbon mixture to produce olefins including preheating a hydrocarbon feed, mixing the pre-heated hydrocarbon stream with a steam feed, feeding the mixed hydrocarbon steam stream to a second preheat zone, heating air, combusting the combustion air feed, cracking hydrocarbons, recovering a cracked hydrocarbon product, and quenching the cracked hydrocarbon product. A pyrolysis system for converting a hydrocarbon mixture to produce olefins including a pyrolysis heater, a first and a second preheat zone of a convection heating zone, an electric heater, a heat transfer fluid heating coil, an air feed electric heater, a radiant heating zone, and a feed line. Also disclosed is a process for retrofitting an existing pyrolysis system including removing a secondary transfer line exchanger, adding an electric heater, adding a flow line, replacing or repurposing one or more coils, and adding an air feed electric heater.

A system for steam cracking a whole crude that may include a volatilization device, a control system, a separator, and a steam pyrolysis reactor. The volatilization device may be configured to separate a vapor phase from a liquid phase. The control system may be configured to maintain a flow rate of the whole crude and steam, at an initial relative velocity of less than 30 m/s. The separator may be fluidly connected to the volatilization device and configured to separate the liquid phase into a second vapor phase, and a second liquid phase. The steam pyrolysis reactor may include a convection section and a steam pyrolysis heater section, the convection section configured to heat the vapor phase, the liquid phase, and the second vapor phase, and the steam pyrolysis heater section configured to steam crack hydrocarbons in the vapor phase thereby generating a cracked hydrocarbon product.

Catalysts and catalytic methods are provided. The catalysts and methods are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane.

A process for dehydrogenating a paraffinic feedstock, producing olefins and/or dienes. The process includes feeding a paraffinic hydrocarbon feedstock comprising one or more C2+ paraffinic hydrocarbons and a fuel gas stream to a dehydrogenation reactor preheater, combusting the fuel gas stream in the dehydrogenation reactor preheater and heating the paraffinic hydrocarbon feedstock to a temperature in the range of 500-650° C., producing a heated paraffinic feedstock, feeding the heated paraffinic feedstock to a first dehydrogenation reactor operating in a reaction mode and containing an active dehydrogenation catalyst and at least one first electrical heating element, heating the heated paraffinic feedstock in the first dehydrogenation reactor using the at least one first electrical heating element, and contacting the heated paraffinic feedstock with the active dehydrogenation catalyst and the at least one electrical heating element thereby producing an olefinic product stream comprising one or more olefins.

A process and system for producing bio or fossil fuels is provided. The process includes: feeding mixed hydrocarbon to a fixed-bed reactor system containing a zeolite catalyst; operating the fixed-bed reactor system for oligomerization of one or more C3-C8 hydrocarbons to form an oligomerized effluent; separating the oligomerized effluent into a C3-fraction, a gas stream, and a liquid stream in a gas/liquid separation unit; feeding at least a first portion of the liquid stream to a distillation unit; recycling at least a second portion of the liquid stream to the fixed-bed reactor system; separating the first portion of the liquid stream in the distillation unit into, a light fraction and a heavy fraction; and recycling the light fraction to the fixed-bed reactor system.

Processes and systems for recovering hydrogen include feeding a gas stream, comprising hydrogen and additional gases, to a pressure swing adsorption (PSA) system and feeding a membrane permeate stream comprising hydrogen to the PSA system. In the PSA system, a portion of the hydrogen is separated from the additional gases to recover a hydrogen product stream and a PSA tail gas stream comprising unseparated hydrogen and the additional gases. The PSA tail gas stream is fed to a membrane separation unit for separating hydrogen from the additional gases and to recover (i) the membrane permeate stream comprising hydrogen fed to the PSA system and (ii) a membrane tail gas stream comprising the additional gases. Processes and systems herein may additionally include a refrigeration system for partially condensing one or both of the feed gas stream and the PSA tail gas stream, enhancing the efficiency of the membrane separation unit.

Systems and processes for the production of a high purity isobutylene stream, a high purity isooctene stream or for the co-production of a high purity isobutylene and a high purity isooctene. The systems and processes advantageously process mixed C4 hydrocarbon streams via etherification, back cracking, isomerization, and/or dimerization, along with various separation systems, to produce the desired high purity streams.

Systems and processes for the flexible production of gasoline and jet fuel via alkylation of C4 and C5 olefins.