Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
  • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
  • F25J3/0204—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the feed stream
  • F25J3/0223—H2/CO mixtures, i.e. synthesis gas; Water gas or shifted synthesis gas
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  • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
  • C01B3/50—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification
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  • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
  • C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
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  • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
  • C01B3/50—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification
  • C01B3/501—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification by diffusion
  • C01B3/503—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification by diffusion characterised by the membrane
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  • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
  • C01B3/50—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification
  • C01B3/506—Separation of hydrogen or hydrogen containing gases from gaseous mixtures, e.g. purification at low temperatures
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
  • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
  • F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
  • F25J3/0233—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of CnHm with 1 carbon atom or more
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
  • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
  • F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
  • F25J3/0252—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of hydrogen
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J3/00—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification
  • F25J3/02—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream
  • F25J3/0228—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream
  • F25J3/0261—Processes or apparatus for separating the constituents of gaseous or liquefied gaseous mixtures involving the use of liquefaction or solidification by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream characterised by the separated product stream separation of carbon monoxide
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  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/02—Processes for making hydrogen or synthesis gas
  • C01B2203/0205—Processes for making hydrogen or synthesis gas containing a reforming step
  • C01B2203/0227—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step
  • C01B2203/0238—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step the reforming step being a carbon dioxide reforming step
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  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/02—Processes for making hydrogen or synthesis gas
  • C01B2203/0205—Processes for making hydrogen or synthesis gas containing a reforming step
  • C01B2203/0227—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step
  • C01B2203/0244—Processes for making hydrogen or synthesis gas containing a reforming step containing a catalytic reforming step the reforming step being an autothermal reforming step, e.g. secondary reforming processes
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/02—Processes for making hydrogen or synthesis gas
  • C01B2203/025—Processes for making hydrogen or synthesis gas containing a partial oxidation step
  • C01B2203/0261—Processes for making hydrogen or synthesis gas containing a partial oxidation step containing a catalytic partial oxidation step [CPO]
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
  • C01B2203/0405—Purification by membrane separation
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
  • C01B2203/042—Purification by adsorption on solids
  • C01B2203/043—Regenerative adsorption process in two or more beds, one for adsorption, the other for regeneration
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/04—Integrated processes for the production of hydrogen or synthesis gas containing a purification step for the hydrogen or the synthesis gas
  • C01B2203/0465—Composition of the impurity
  • C01B2203/0475—Composition of the impurity the impurity being carbon dioxide
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  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/08—Methods of heating or cooling
  • C01B2203/0805—Methods of heating the process for making hydrogen or synthesis gas
  • C01B2203/0811—Methods of heating the process for making hydrogen or synthesis gas by combustion of fuel
  • C01B2203/0827—Methods of heating the process for making hydrogen or synthesis gas by combustion of fuel at least part of the fuel being a recycle stream
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/14—Details of the flowsheet
  • C01B2203/148—Details of the flowsheet involving a recycle stream to the feed of the process for making hydrogen or synthesis gas
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
  • C01B2203/80—Aspect of integrated processes for the production of hydrogen or synthesis gas not covered by groups C01B2203/02 - C01B2203/1695
  • C01B2203/84—Energy production
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2205/00—Processes or apparatus using other separation and/or other processing means
  • F25J2205/40—Processes or apparatus using other separation and/or other processing means using hybrid system, i.e. combining cryogenic and non-cryogenic separation techniques
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25J—LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS OR LIQUEFIED GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT OR BY BRINGING THEM INTO THE SUPERCRITICAL STATE
  • F25J2245/00—Processes or apparatus involving steps for recycling of process streams
  • F25J2245/02—Recycle of a stream in general, e.g. a by-pass stream

Definitions

• the present invention relates to a method for reducing carbon dioxide emissions from boilers, gas turbines and / or integrated steam and power generation units at a syngas production site.
• the invention relates to different sectors of activity, such as heavy chemistry, the petrochemical industry, the refining industry, the energy industry, all concerned with environmental protection.
• a synthesis gas is a mixture of CO, H 2 , CH 4 , CO 2 and H 2 O obtained by steam reforming (SMR), the partial oxidation of hydrocarbons or by autothermal reforming ("autothermal reforming" or ATR).
• SMR steam reforming
• autothermal reforming autothermal reforming
• ATR autothermal reforming
• Steam reforming is a process used to produce a high carbon synthesis gas from hydrocarbons ranging from natural gas to heavy naphtha.
• the partial oxidation process or POX is a non-catalytic reaction between hydrocarbons, coke or coal with steam and oxygen at high temperature and pressure.
• the synthesis gas can also be obtained by combining the SMR reforming and the partial oxidation in the same reactor according to the autothermal reforming process.
• the hydrocarbons treated with ATR are generally natural gas and naphtha. This ATR process leads to synthesis gases with a low H 2 / CO ratio.
• the synthesis gas also includes nitrogen when the base reagent is natural gas.
• the invention relates to syngas production sites in which technologies producing heat and / or electricity ("combined heat and / or power" or CHP in English) such as conventional boilers are also used. In the energy industry, these CHP technologies can be electricity cogeneration plants that consist of an open cycle or a combined cycle.
• Cogeneration is the simultaneous generation of electricity and steam where electricity is generated by an alternator driven by a turbine (usually a gas or steam turbine) and where the heat comes from the heat of the exhaust gases from the engine. a boiler producing steam or hot water.
• a turbine usually a gas or steam turbine
• This combined generation of two types of energy leads to high efficiency efficiencies compared to the separate and conventional production of heat and / or electricity.
• syngas, steam and electricity derivatives there is a growing search for production sites that can simultaneously supply syngas, steam and electricity. .
• a common problem of these production sites is to be able to respond to these environmental constraints by limiting the release of carbon dioxide.
• a complementary problem is to find a solution to the storage of the carbon dioxide removed from the gases produced by the synthesis gas unit while having improved reliability, reduced costs and respect for the environment.
• the object of the present invention is to provide a synthesis gas production process, on a site also comprising a heat generating unit and / or electricity, releasing little carbon dioxide.
• Another object of the present invention is to provide a synthesis gas production process, on a site also comprising a heat and / or electricity production unit, releasing little carbon dioxide and not requiring storage of the carbon dioxide.
• Another aim is to propose a synthesis gas production process, on a site also comprising a heat and / or electricity production unit, releasing little carbon dioxide and allowing a control of the H 2 / CO ratio of the synthesis gas produced.
• the invention relates to a process for producing a synthesis gas by means of a synthesis gas production unit comprising:
• At least one synthesis gas production reactor producing from hydrocarbons:
• a raw synthesis gas comprising hydrogen, CO and CO 2 and an exhaust gas comprising CO 2
• a device for removing CO 2 from said crude synthesis gas producing a gas essentially comprising CO 2 , said gas essentially comprising CO 2 being recycled into the synthesis gas production reactor, at an industrial site further comprising:
• At least one of the exhaust gases comprising CO 2 produced by the synthesis gas production reactor or by the heat and / or electricity generating unit is treated in the CO 2 removal device of the combustion exhaust gas from the site, and
• the CO 2 produced by treatment of the exhaust gases of the synthesis gas production unit and / or of the heat and / or electricity production unit by the device for removing CO 2 from the gases Combustion exhaust from the site is recycled at least in part into the syngas production reactor.
• FIGS. 1 to 4 are diagrammatic representations of several variants of the method according to the invention.
• the method according to the invention therefore implements a synthesis gas production unit comprising at least, on the one hand, the synthesis gas production reactor for obtaining the raw synthesis gas, and on the other hand , a device for treating this raw synthesis gas to remove carbon dioxide.
• the synthesis gas production reactor for obtaining the raw synthesis gas may be a steam reforming reactor (SMR) or a partial oxidation reactor (POX) using hydrocarbons to produce the raw synthesis gas comprising hydrogen, carbon monoxide, carbon dioxide and other compounds. It can also be a reactor for the implementation of an ATR process. Due to the implementation of a combustion in the synthesis gas production reactor (combustion intended to raise the temperature of the reactor for the implementation of the synthesis reaction), the synthesis gas production reactor produces also an exhaust gas in addition to the synthesis gas. This exhaust gas comprises CO 2 since it usually comes from the combustion of hydrocarbons.
• the device for treating raw synthesis gas to remove carbon dioxide therefrom is preferably an amine scrubbing method generally using the MDEA (methyldiethanolamine).
• the CO 2 is removed from the raw synthesis gas in the form of a gas comprising essentially CO 2 (i.e. comprising at least 99% by volume of CO 2 ) which is recycled as a reactant in the reactor producing synthesis gas.
• the synthesis gas production unit comprises a device for removing CO from the synthesis gas producing a gas essentially comprising CO and a gas essentially comprising H 2 .
• This mode is implemented when the industrial site aims to produce mainly carbon monoxide.
• This device for removing CO from the synthesis gas is usually disposed after the CO 2 removal device of said raw synthesis gas.
• the device for removing CO from the synthesis gas usually comprises a drying device and a cold box. Thus, the synthesis gas from the CO 2 removal device is first dried before being introduced into a cold box, in which its various compounds are separated cryogenically.
• the cold box produces at least one gas comprising substantially CO (i.e., preferably comprising at least 98% by volume of CO), a gas comprising essentially H 2 (i.e., preferably comprising minus 97% by volume of H 2 ), a gas comprising essentially CH 4 (that is to say preferably comprising at least 99% by volume of CH 4 ) and a residual gas comprising a mixture of H 2 , CO and CH 4 .
• the recycling of CO 2 upstream of the cold box makes it possible to reduce the amount of nitrogen in the gas essentially comprising CO.
• the waste gas, the gas comprising essentially CH 4 and the gas comprising essentially H 2 can be used as fuels in all the combustion reactions implemented at the industrial site and in particular in the combustion reaction implemented in the production reactor.
• the synthesis gas production unit preferably comprises a gas purification device essentially comprising H 2 produced by the device for removing CO from the synthesis gas, said device producing a gas enriched in H 2 .
• This gas purification device comprising essentially H 2 preferably employs a pressure swing adsorption method (PSA).
• This gas purification process essentially comprising H 2 produces a waste gas which essentially comprises a mixture of hydrogen, CO and CH 4 .
• This waste gas can be used as fuel in all the combustion reactions implemented on the industrial site and in particular in the synthesis gas production reactor and the combustion reaction implemented in the heat and / or electricity production unit.
• the synthesis gas production unit comprises a device for adjusting the value of the molar ratio H 2 / CO of the synthesis gas.
• This mode is implemented when the industrial site aims to produce essentially an oxogaz.
• the device for adjusting the value of the molar ratio H 2 / CO of oxogaz generally comprises a membrane permeable to hydrogen.
• the choice of the selectivity of the membrane makes it possible to adjust the H 2 / CO ratio of the oxogas.
• the membrane also produces a hydrogenated permeate that can be used as a fuel in all the combustion reactions at the industrial site and in particular in the synthesis gas production reactor and the combustion reaction implemented in the production unit. heat and / or electricity.
• the permeable membrane may sometimes be preceded by a drying device.
• the industrial site on which the synthesis gas production unit is located furthermore comprises at least one heat and / or electricity production unit (CHP), this unit producing an exhaust gas comprising CO 2 .
• a production unit for heat and / or electricity producing an exhaust gas comprising CO 2 may comprise at least one of the following devices: a gas turbine, a steam production boiler, a steam turbine or a combination thereof, including the combination of the steam boiler with the steam turbine and the combination of the gas turbine with the steam boiler, which may be combined with the steam turbine.
• the gas turbine is a commonly known device comprising an air compressor connected to a gas turbine.
• the compressed air produced is introduced with a fuel into the combustion device of the turbine and the product combustion gases pass through the gas turbine to produce electricity by means of, for example, an alternator.
• the fuel of the gas turbine is usually natural gas; according to the first embodiment of the invention, the natural gas may be mixed with at least one gas chosen from: the gas essentially comprising H 2 produced by the device for removing CO from the synthesis gas, the gas comprising essentially CH 4 produced by the device for removing CO from the synthesis gas, the H 2 enriched gas produced by the purification device, the waste gas from the cold box.
• the steam generating boiler generally consists of a combustion device producing heat to convert water into steam.
• This boiler generally consists of a series of heat exchangers, for example coils, in which water circulates and brought into contact with the heat produced by the combustion.
• This boiler can be combined with a steam turbine: thus, the pressure of the steam produced by the boiler falls back into a steam turbine so as to produce electricity.
• the steam turbine can be either a back-pressure steam turbine that produces steam and electricity, or a steam condensing turbine that produces hot water and electricity.
• the steam turbine may be fed in part by the steam produced by the heat from the synthesis gas production reactor.
• the heat and / or electricity production unit (CHP) produces exhaust gases comprising CO 2 because of the combustions that are implemented therein to provide heat, in particular by combustion of natural gas.
• the industrial site comprises a device for removing CO 2 from the combustion exhaust gas that can be produced on the site.
• This device makes it possible to treat all the exhaust gases resulting from a combustion and comprising CO 2 .
• the exhaust gases from a combustion generally comprise 13 to 16% by volume of oxygen.
• the device for removing CO 2 from these gases must therefore be suitable for the treatment of gases having such an oxygen content. It is not possible, for example, to use the device for removing CO 2 from the raw synthesis gas because a raw synthesis gas contains only a few ppb of oxygen.
• This CO 2 removal device may be an amine wash using MEA (methylethanolamine) or a carbon dioxide adsorption process using sieves or a membrane permeation process.
• MEA methylethanolamine
• a first essential characteristic of the invention is that at least one of the exhaust gases comprising CO 2 produced either by the synthesis gas production reactor or by the heat production unit and / or electricity (CHP), is treated in the CO 2 removal device of the combustion exhaust gas from the site.
• the invention there may be treatment either exhaust gas from the synthesis gas production unit, or exhaust gas from the heat production unit and / or electricity, either exhaust gases from these two units.
• the choice is usually made according to both the CO 2 content of each exhaust gas and the desired recycling rate in the synthesis gas reactor.
• the exhaust gas from the synthesis gas production reactor is preferably mixed with the exhaust gas from the heat and / or electricity production unit (CHP) beforehand its introduction into the CO 2 removal device of the combustion exhaust gas from the site.
• a second essential characteristic of the invention is that the CO 2 produced by the CO 2 removal device of the exhaust gases of the synthesis gas production unit and / or the heat production unit and / or electricity (CHP) is recycled at least in part into the synthesis gas production reactor.
• the CO 2 of the exhaust gas is recycled as a reactant in the synthesis gas reactor. Since the CO 2 produced by the exhaust gas CO 2 device may comprise poisons from the synthesis gas reactor catalysts, this CO 2 may be treated by at least one of the following devices, and preferably both:
• a deoxo reactor charged with alumina for adsorbing iron compounds and comprising downstream a catalyst load of copper and palladium to remove O 2 , C 2 H 4 and NOx.
• the CO 2 can be compressed and undergo temperature changes, for example by means of a heat exchanger, before being reintroduced into the synthesis gas reactor.
• the CO 2 from the CO removal device 2 of the raw synthesis gas and the CO2 treated from the CO removal device 2 of the exhaust gas are mixed before being recycled in the production reactor of synthesis gas.
• the amount of CO 2 produced by the CO 2 removal devices that is recycled to the syngas reactor is adjusted primarily according to the H 2 / CO ratio of the desired synthesis gas.
• the industrial site may require the use of CO 2 as an intermediate in a synthesis step; in this case, some of the CO 2 is not recycled.
• At least a portion of the CO 2 produced by the CO 2 removal devices of the synthesis gas generation and heat and / or electricity generating (CHP) units can be compressed before being recycled as a reactant in the synthesis gas reactor, for example by means of an existing compressor and usually intended for the synthesis gas production unit.
• CHP electricity generating
• the steam turbine of the CHP unit can be coupled to a compressor.
• This compressor can optionally compress the mixture of the exhaust gases produced by the boiler and the synthesis gas production reactor prior to their introduction into the CO 2 removal device of the combustion exhaust gases from the site, particularly if the disposal device is a adsorption process or membrane permeation process. This compression allows improved subsequent treatment of gases.
• the H 2 / CO ratio of the raw synthesis gas can be controlled by the recycle rate of the CO 2 produced by the CO 2 removal devices of the gas production unit. synthesis and the heat and / or electricity production unit in the synthesis gas production reactor.
• the synthesis gas production unit may not comprise a device for adjusting the value of the molar ratio H 2 / CO of the synthesis gas, such as a membrane.
• the process according to the invention making it possible to control the H 2 / CO ratio at the outlet of the synthesis gas production reactor, it is therefore possible to eliminate the device for adjusting the value of the molar ratio H 2. / CO (membrane for example) when the product manufactured by the synthesis gas production unit is an oxogaz.
• FIG. 1 illustrates the method according to the invention.
• Hydrocarbons 2 undergo a catalytic reforming or partial oxidation or autothermal reforming (ATR) reaction in the reactor 1 so as to produce the crude synthesis gas 3.
• the reactor 1 also produces an exhaust gas 4 comprising the gases from the combustion of hydrocarbons used as fuels (and not as reagents).
• the synthesis synthesis gas 3 is treated in the CO 2 elimination unit 5, which produces a CO 2 depleted synthesis gas 19 and a CO 2 -rich effluent 12.
• the CO 2 depleted synthesis gas 19 is then dried in the dryer 13 to increase the removal of CO 2 and water and prevent their presence in the cold box 7.
• the dried gas 16 is treated in a cold box 7.
• the temperature of the Dried synthesis gas 16 is lowered so as to separate the CO from the other compounds (H 2 , N 2 and CH 4 ). It produces a gas comprising essentially CO 18, a gas essentially comprising H 2 9 and a waste gas 15.
• the waste gas 15, which leaves the exhaust column (commonly referred to as "flash gas"), is a mixture of H 2 , CO and CH 4 which can be used as fuel for the synthesis gas production reactor 1 or in a combustion reaction implemented in the heat and / or electricity production unit.
• the purge of methane 31 that leaves the bottom of the CO / CH 4 separation column of the cold box 7 may also be used as fuel or reagents of the synthesis gas production reactor 1, depending on the value of its pressure and the conditions required for the catalytic reaction.
• the gas comprising essentially H 2 9 leaving the cold box 7 can be treated in a hydrogen purification process 22 to produce high purity hydrogen 28 and a waste gas 29 (also called "tail gas" in English) .
• the waste gas 29 is used as a fuel in the synthesis gas production reactor 1 and in the combustion reaction implemented in the heat and / or electricity production unit.
• the industrial site also comprises a heat and / or electricity production unit 6 whose heat is obtained by combustion of hydrocarbons 2 and gas comprising essentially H 2 9 of the cold box.
• This unit 6 produces electricity 23 and an exhaust gas 8 comprising carbon dioxide.
• This exhaust gas 8 is mixed with the exhaust gas of the synthesis gas production reactor 4.
• This exhaust gas mixture (8 + 4) is treated by the CO 2 removal device 10 of the exhaust gas. combustion exhaust of the site.
• This device 10 is preferably selected from CO 2 removal devices for treating a low pressure effluent with a low oxygen content. From this device 10 there emerges a CO 2 poor exhaust gas and a CO 2 -rich effluent 11, which is mixed with the CO 2 -rich effluent from the CO 2 elimination device 5.
• synthesis gas production unit This mixture (11 + 12) rich in CO 2 can be compressed by a compressor 21 before being introduced into the reactor 1 with the hydrocarbons 2.
• the CO 2 poor exhaust gas can be released into the atmosphere with a very low CO 2 content compared to other
• Air or oxygen (not shown) is provided for all devices employing combustion 1, 6.
• FIG. 2 differs from FIG. 1 in that the heat and / or electricity production unit 6 is a combination of a gas turbine 63, a boiler 61 and a steam turbine 62.
• the gas turbine 63 operates by combustion of hydrocarbons 2 and gas comprising essentially H 2 9 of the cold box.
• the boiler 61 receives the exhaust gas 24 from the gas turbine 63; it is supplied with water 17 and produces steam 30 which is used to turn the steam turbine 62 to produce electricity 231.
• the steam turbine 62 can also be fed by the steam 14 produced by the contacting. of water with the reactor 1.
• the water vapor 31 leaving the steam turbine 62 can be used for the implementation of the CO 2 removal treatment in the device 10.
• the gas turbine 63 operates by means of hydrocarbon 2 and gas comprising essentially H 2 9 from the cold box 7. It produces electricity 232 and a combustion gas 24 which is used partly for the combustion implemented in the boiler 61 and partly for combustion implemented in the synthesis gas production reactor 1.
• the electricity produced by the turbines 62 and 63 may be exported or used within the site to operate electrical auxiliaries.
• Figures 3 and 4 differ respectively from Figures 1 and 2 in that the unit of synthesis gas is intended to produce an oxogas. Consequently, the cold box is replaced by a device for adjusting the H 2 / CO molar ratio of the synthesis gas producing an oxogas 27 and a gas comprising essentially hydrogen (and a lower portion of CO) which can be used in the synthesis gas production reactor 1 and in the heat and / or electricity generation unit 6.
• the synthesis gas can be optionally dried by a drying device 13 before being introduced into the membrane. According to one particular embodiment, the dried synthesis gas can directly present the molar ratio H 2 / CO of the desired oxogaz.
• the membrane 26 can then be replaced by a simple condenser, the recovered condensed water can be reused in the synthesis gas production reactor (1) or in the heat production unit and / or electricity (6, 61).
• An advantage of the process is that it makes it possible to reduce the consumption of hydrocarbons, for example natural gas, naphtha or liquefied petroleum gas (LPG) because of the recycling of CO 2 in the synthesis gas production reactor.
• hydrocarbons for example natural gas, naphtha or liquefied petroleum gas (LPG)
• Another advantage of the invention is that a carbon recovery rate of the order of almost 100% can be obtained if the whole of the CO 2 from the exhaust gas is recycled.
• the method according to the invention has the advantage of allowing the reduction of the H 2 / CO ratio downstream of the CO 2 removal device of the synthesis gas production unit. This reduction is obtained by recycling the CO 2 of the various devices producing gases containing CO 2 . By recycling them in the syngas reactor, the product gas has a lower H 2 concentration.
• the base case corresponds to a site including a synthesis gas production unit and a heat and / or electricity production unit in which there is no recycle of CO 2 produced by the unit generating heat and / or electricity (8) or from the exhaust gas of the synthesis gas production reactor to the synthesis gas production unit (4).
• the CO 2 (12) from the CO 2 removal process of the raw synthesis gas is recycled.
• - Case 2 corresponds to the same site as in the base case, but with recycling of CO 2 from the exhaust gases of the synthesis gas production reactor and the CO 2 resulting from the exhaust gas of the unit of production of heat and / or electricity to the synthesis gas production unit.
• the preheated natural gas is introduced into the synthesis gas production reactor which is a steam reforming reactor (SMR), after undergoing a hydrodesulphurization treatment to remove traces of sulfides.
• SMR steam reforming reactor
• the recycled CO 2 from the CO removal device 2 of the unit of production of synthesis gas. This recycled CO 2 is previously compressed. All these reagents are heated to 650 ° C. and introduced into the tubes filled with nickel-based catalysts of the SMR reactor at 25 bars.
• the device for removing CO 2 from the crude synthesis gas is an amine wash. It makes it possible to produce a synthesis gas having a CO 2 content of less than 50 ppm by volume.
• the gas turbine 63 is a Solar Mars 100 model.
• the unit for removing CO 2 from the exhaust gases of the heat and / or electricity production unit is an amine wash
• the purity of the dry CO 2 obtained is 99.9% by volume at room temperature and below about 0.55 effective bar.
• Table 1 compares the processes of each case and their economic impact.
• This example shows the economic interest in recycling the CO 2 produced by all the units in the SMR reactor so as to reduce the consumption of total natural gas (used as reagent and fuel).
• the consumption of the total natural gas consumed by the synthesis gas production unit is already reduced to 71% of the base case.
• the H 2 / CO ratio is lowered to 1.1 and the consumption of the total natural gas consumed by the synthesis gas production unit is reduced by up to 57% compared to the base case. .
• the graph of FIG. 5 gives the molar ratio H 2 / CO (abscissa) at the outlet of the synthesis gas production reactor as a function of the amount of CO 2 (in Nm 3 / h) (ordinate) recycled in the reactor. of synthesis gas production.
• H 2 or CO the process according to the invention makes it possible to flexibly vary the H 2 / CO ratio by adjusting the recycle rate of CO 2 , or even the import of CO 2 . This also makes it possible to avoid the addition of a membrane upstream of the cold box or the PSA.

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• 2005
  • 2005-02-01 FR FR0550297A patent/FR2881417B1/fr not_active Expired - Fee Related
• 2006
  • 2006-01-24 JP JP2007552691A patent/JP2008528423A/ja not_active Withdrawn
  • 2006-01-24 CN CNA2006800035964A patent/CN101111453A/zh active Pending
  • 2006-01-24 KR KR1020077017675A patent/KR20070100962A/ko not_active Application Discontinuation
  • 2006-01-24 EP EP06709434A patent/EP1846324A1/fr active Pending
  • 2006-01-24 WO PCT/FR2006/050050 patent/WO2006082332A1/fr active Application Filing
  • 2006-01-24 US US11/815,250 patent/US20080272340A1/en not_active Abandoned

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