Classifications

• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • 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
  • C01B3/32—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air
  • C01B3/34—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents
  • C01B3/36—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by reaction of gaseous or liquid organic compounds with gasifying agents, e.g. water, carbon dioxide, air by reaction of hydrocarbons with gasifying agents using oxygen or mixtures containing oxygen as gasifying agents
• • C—CHEMISTRY; METALLURGY
  • C01—INORGANIC CHEMISTRY
  • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
  • C01B32/00—Carbon; Compounds thereof
  • C01B32/40—Carbon monoxide
• • 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
  • C01B2203/0205—Processes for making hydrogen or synthesis gas containing a reforming step
  • C01B2203/0211—Processes for making hydrogen or synthesis gas containing a reforming step containing a non-catalytic reforming step
  • C01B2203/0222—Processes for making hydrogen or synthesis gas containing a reforming step containing a non-catalytic reforming step containing a non-catalytic carbon dioxide reforming step
• • 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
  • C01B2203/0255—Processes for making hydrogen or synthesis gas containing a partial oxidation step containing a non-catalytic partial oxidation step
• • 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
  • C01B2203/0415—Purification by absorption in liquids
• • 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
  • C01B2203/12—Feeding the process for making hydrogen or synthesis gas
  • C01B2203/1205—Composition of the feed
  • C01B2203/1211—Organic compounds or organic mixtures used in the process for making hydrogen or synthesis gas
  • C01B2203/1235—Hydrocarbons
• • 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
  • C01B2203/12—Feeding the process for making hydrogen or synthesis gas
  • C01B2203/1258—Pre-treatment of the feed

Definitions

• the invention relates to a method for producing a synthesis gas mixture.
• a material use of by-product streams can be made possible by special gasification technologies in which the by-product stream is converted to synthesis gas together with gasifying agents such as pure oxygen, steam and/or CO2, which contains carbon monoxide (CO) and hydrogen (H2) as valuable components.
• gasifying agents such as pure oxygen, steam and/or CO2, which contains carbon monoxide (CO) and hydrogen (H2) as valuable components.
• fossil carbon carriers such as coal, refinery residues (HVR - heavy vacuum residue) or natural gas, or biogenic materials such as wood or straw are converted into a synthesis gas in a gasifier.
• HVR refinery residues
• biogenic materials such as wood or straw are converted into a synthesis gas in a gasifier.
• the disadvantage is that the conversion takes place with the formation of CO2.
• Carbonaceous input materials such as coal, refinery residues or gaseous substances such as natural gas are partially oxidized in the gasifier in a non-catalytic, autothermal high-temperature and high-pressure process (POX process).
• POX process autothermal high-temperature and high-pressure process
• Carbon monoxide represents one product of value
• the other product of value is hydrogen.
• the amount produced depends on the amount of bound hydrogen in the feedstock and the amount of water vapor added.
• the cleaned product gas stream which essentially consists of hydrogen and carbon monoxide, is referred to as synthesis gas.
• the H2/CO ratio can vary. It depends on the feedstock used and the gasification process selected and can be 0.6-0.8 for coal, 0.8-1.0 HVR and 1.5-1.9 for natural gas.
• the object of the invention is to provide a method for producing synthesis gas in which a synthesis gas with an H2/CO ratio suitable for the oxo synthesis is obtained.
• the object of the invention is also to use carbonaceous material streams occurring as by-products, which would otherwise be thermally utilized, and thus to reduce CC>2 emissions overall.
• the object of the invention is also to provide a method for the production of synthesis gas which can function as a CC>2 sink.
• the object is achieved by a method for producing a synthesis gas mixture containing hydrogen and carbon monoxide by non-catalytic partial oxidation of hydrocarbons in the presence of oxygen and carbon dioxide, in which at least one reactant gas containing hydrocarbons, one reactant gas containing oxygen and one reactant gas containing carbon dioxide are fed into a partial oxidation reactor and reacted at a temperature in the range from 1200 to 1550 °C to form a product gas mixture containing hydrogen, carbon monoxide and carbon dioxide, with at least part of the carbon dioxide being separated off from the product gas mixture and returned to the partial oxidation reactor, characterized in that that the carbon dioxide fed into the partial oxidation reactor contains additional, imported carbon dioxide, whereby in the partial oxidation reactor a product gas mixture with a molar ratio of W hydrogen to carbon monoxide in the range of 0.8:1 to 1.6:1 is obtained.
• Hydrocarbons within the meaning of the present invention are compounds containing carbon and hydrogen and can also include oxygenates such as methanol, ethanol and dimethyl ether. These are often present as secondary components in the hydrocarbon-containing reactant streams.
• the educt hydrocarbons contain at least 80% by volume of hydrocarbons containing only C and H, such as alkanes, cycloalkanes, alkenes and aromatic hydrocarbons, preferably they contain at least 80% by weight of alkanes (straight-chain, branched and optionally cyclic alkanes ) with generally 1 to 6 carbon atoms.
• the new process allows the generation of a synthesis gas with CC>2 consumption.
• the H2/CO ratio By additionally importing further CO2 from external sources, it is possible to set the H2/CO ratio optimally. It is even possible to adjust the H2/CO ratio of approx. 1:1 required for the oxo synthesis directly in the synthesis gas generation stage without subsequent enrichment or depletion stages.
• the methane content at the outlet of the synthesis gas reactor is generally ⁇ 1.5% by volume, preferably ⁇ 0.2% by volume or even ⁇ 0.05% by volume.
• the method according to the invention allows the material use of carbon-containing by-product streams and CO2 released in any other production processes, whereby a maximum amount of carbon is bound in the synthesis gas. If required process heat or mechanical process energy is provided by renewable energy sources, otherwise thermally utilized carbonaceous by-product streams are free for material utilization. Carbon-containing material streams that would otherwise have been burned to generate heat or steam, releasing CO2, can be used according to the invention as feedstock for the synthesis gas generation. What are great hydrogen to carbon ratios in the educt hydrocarbons are advantageous because then large amounts of carbon dioxide can be imported into the process and recycled.
• the optimal reactant hydrocarbon is methane with a hydrogen to carbon ratio of 4:1.
• the reaction generally takes place under high pressure, generally at pressures of from 1 to 100 bar, preferably from 10 to 60 bar, particularly preferably from 20 to 60 bar.
• the interior of the partial oxidation reactor is generally cylindrical, with one or more burners being located on the top surfaces. Local temperatures of over 2000°C are possible in the area where oxygen enters (flame).
• dry reforming, sum equation CH4 + 2CO + 2H2 the gas phase cools down and reactor outlet temperatures of 1200 to 1550°C are reached.
• This gas reforming reaction at 1200 to 1550° C., preferably 1250 to 1400° C., achieves the high synthesis gas yield and almost complete hydrocarbon conversion (in particular methane conversion).
• the carbon dioxide produced during the partial oxidation in the gasifier is then separated from the raw synthesis gas by means of gas scrubbing and returned to the gasifier.
• the gas scrubbing can be carried out according to the prior art.
• the raw synthesis gas is washed with an amine-containing washing agent in a washing column in countercurrent, with the CO2 contained in the raw synthesis gas being almost completely absorbed by the amine.
• the raw synthesis gas is cooled down to 30-70°C before it enters the washing column in order to avoid thermal stress on the amine.
• the CO2-enriched scrubbing agent is then regenerated in a desorber column with the addition of heat.
• the regenerated detergent can then be used again in the washing column in a circuit.
• the CO2 generally leaves the desorber column at the top of the column without pressure. To return the CO2 to the partial oxidation reactor, it is first brought to system pressure in a compressor.
• additional CO2 is imported from external sources depending on the required H2/CO ratio.
• the mole fractions of the educts C x H y / CO2/ O2 fed to the partial oxidation process, including the recirculated CO2, are 0.19 - 0.57 / 0.02 - 0, depending on the H/C ratio in the educt hydrocarbon stream .30 / 0.31 - 0.70, depending on the desired H2/CO ratio in the raw synthesis gas.
• Exemplary CxHy / CO2/ 02 molar fractions Mol / SMoI; Total 1.0
• Table 1 Educt compositions for the gasifier in mol/mol for different H2/CO ratios for a reactor outlet temperature of 1250 °C and at 46 bar(a)
• the molar ratio of hydrogen to carbon monoxide in the product gas mixture of the partial oxidation is in the range from 0.8:1 to 1.6:1.
• a molar ratio of hydrogen to carbon monoxide of 0.8:1 to 1.2:1 is preferred , more preferably from 0.9:1 to 1.1:1.
• the carbonaceous component is methane.
• the molar proportions of the reactants CH4 / CO2 / O2 fed into the partial oxidation process, without the recycled CO2 are 0.50 / 0.13 / 0.37.
• Methane as an educt hydrocarbon thus enables the largest C0 2 import at a hh / CO ratio of 1: 1 in the synthesis gas. This can be used directly, ie without further concentration or depletion stages, in subsequent syntheses (oxo syntheses, hydroformylation).
• H2:CO 1:1
• This amount decreases with increasing chain length of the educt hydrocarbon and is still 0.201 C0 2 /t for ethane, 0.131 C0 2 /t for propane, 0.101 CO2 for butane and for
• the hydrocarbon-containing reactant gas from the partial oxidation preferably contains methane.
• the molar ratio is methane:oxygen:carbon dioxide in the reactant gases of the overall process, ie comprehensively imported and recycled CO2, in total preferably 0.39 to 0.57:0.30 to 0.40:0.05 to 0.30, more preferably 0.39 to 0.57:0.31 to 0.38:0, 05 to 0.30.
• the methane contained in the educt gas of the partial oxidation is preferably obtained in a steamer field.
• the naphtha produced in a petroleum refinery is often used as the educt mixture for the steam cracking process.
• the actual cracker is a tubular reactor with a chromium/nickel alloy coil and is located in a flame-heated furnace.
• the educt mixture is, for example, preheated to 550 to 600° C. at about 12 bar in the convection zone of the furnace.
• Process steam at a temperature of 180 to 200°C is also added in this zone. This brings about a reduction in the partial pressure of the individual reactants and also prevents polymerization of the reaction products.
• the completely gaseous educt mixture reaches the radiation zone. Here it is cracked at, for example, 1050°C to form the low-molecular hydrocarbons.
• the residence time is, for example, about 0.2-0.4 s.
• Ethene, propene, 1,2- and 1,3-butadiene, /7- and butene, benzene, toluene, xylenes are formed.
• hydrogen and methane are also formed in considerable amounts of, for example, about 16% by weight, as well as other, sometimes disruptive, by-products such as ethyne, propyne (in traces), propadiene (in traces) and, as part of the pyrolysis gasoline, n -, A and cj/c/o paraffins and olefins, Cg and Cio aromatics.
• the heaviest fraction is the so-called ethylene cracker residue with a boiling range of, for example, 210-500°C.
• the hot cracked gas is abruptly cooled in a heat exchanger to around 350 to 400°C.
• the hot cracked gas is then additionally cooled with quench oil to 150 to 170°C for the subsequent fractionation.
• the product flow at the furnace outlet contains a large number of substances that are then separated from one another.
• the valuable products ethene and propene are generally obtained in a very high purity.
• the substances that you do not want to win as a product are partly returned to the cracker, partly incinerated.
• Processing begins with the oil wash and the water wash, in which the still hot gas is further cooled and heavy impurities such as coke and tar are separated out.
• the cracked gas is first compressed in stages to, for example, approx. 30 bar.
• the acidic gases are absorbed in a caustic wash.
• An adsorptive dryer removes water.
• Methane can, for example, be separated from ethyne, ethene and ethane at 13 bar and -115°C.
• the main products especially ethene and propene, are obtained in pure form.
• the butene isomers can be used for various petrochemical processes, e.g. the /so-butene for the production of MTBE and ETBE, /butenes for the production of alkylate.
• Pyrolysis gasoline is the raw material for the production of benzene and toluene.
• Fractions that are not desired as products, especially alkanes, can be recycled to the cracker.
• the fractions that are not suitable for cracking, in particular hydrogen and methane, have so far mostly been burned in the cracking furnaces and supply the energy required for the process.
• the tar-like residue is either burned in a power plant, sold as a binder to make graphite electrodes, or used to make carbon black.
• the methane is obtained as a by-product in the propane dehydrogenation.
• the carbon dioxide contained in the at least one reactant gas stream is obtained in the ammonia synthesis.
• Ammonia is produced by the equilibrium reaction between hydrogen and nitrogen (N2+ 3H 2 2NH3).
• the hydrogen is produced on an industrial scale by steam reforming natural gas, which in the first step produces a synthesis gas mixture of H2 and CO.
• a subsequent water-gas shift stage CO + H2O - H2 + CO2
• the hydrogen produced in this way generates around 10 tons of carbon dioxide per ton of hydrogen.
• the CO2 is separated by an acid gas scrubber and, after a compression stage, is available in pure form as a starting material for the partial oxidation process described here.
• the carbon dioxide imported into the partial oxidation reactor is obtained in the ethylene oxide synthesis.
• the large-scale production of ethylene oxide takes place through the catalytic oxidation of ethene with oxygen at temperatures of 230-270°C and pressures of 10-20 bar.
• Finely divided silver powder which is applied to an oxidic support, preferably aluminum oxide, is used as the catalyst.
• the reaction is carried out in a tube bundle reactor, in which the considerable heat of reaction is dissipated with the aid of molten salt and used to generate superheated high-pressure steam.
• the yield of pure ethylene oxide is, for example, 85%.
• the complete oxidation of ethene to carbon dioxide and water occurs as a side reaction.

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• 2022
  • 2022-03-24 US US18/283,886 patent/US20240051825A1/en active Pending
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