WO2013135667A1

WO2013135667A1 - Method for producing synthesis gas

Info

Publication number: WO2013135667A1
Application number: PCT/EP2013/054959
Authority: WO
Inventors: Alexander Karpenko; Vanessa GEPERT; Emanuel Kockrick; Leslaw Mleczko; Albert TULKE; Daniel Gordon Duff; Ludger KASTER; Daniel Wichmann
Original assignee: Bayer Intellectual Property Gmbh
Priority date: 2012-03-13
Filing date: 2013-03-12
Publication date: 2013-09-19

Abstract

The method comprises the steps of providing a flow reactor, defining threshold values, comparing energy prices, energy composition with regard to renewable sources, and/or desired ratios of H₂ to CO, and selecting between the operating modes of dry reforming/steam reforming and reverse water gas shift reaction. The threshold value S1 concerns the costs of the electrical energy available for the flow reactor, and the threshold value S2 concerns the relative share of electrical energy from renewable sources of the electrical energy available for the flow reactor. A third threshold value S3 contains the desired H₂/CO ratio in the product gas. Either dry reforming and/or steam reforming or RWGS is performed depending on the threshold values.

Description

V experienced for the production of svnthesegas

The present invention relates to a process for the production of synthesis gas, comprising the steps of providing a flow reactor, setting thresholds, comparing energy prices, energy composition with respect to regenerative sources and / or desired ratios of IL to CO, and selection between dry reforming / steam reforming modes on the one hand and reverse water gas shift reaction on the other.

Due to the increased expansion of renewable energies, a fluctuating supply of energy in the power grid is created. In phases of favorable electricity prices results for the operation of reactors for carrying out endothermic reactions, preferably for the production of synthesis gas, the possibility of an economical and economically meaningful operation taking advantage of renewable energies when they are electrically heated.

In phases in which no regeneratively generated electrical energy is available, then another form of energy supply of the endothermic reactions must be selected.

Conventionally, the synthesis of synthesis gas takes place by means of the steam reforming of methane. Due to the high heat demand of the reactions involved erfo lling their implementation in externally heated reformer tubes. Characteristic of this method is the limitation by the reaction equilibrium, a Wärmransportiimitierung and especially the pressure and temperature limitation of the reformer tubes used (nickelbased steels). Temperature and pressure side results in a limitation to a maximum of 900 ° C at about 20 to 40 bar.

An alternative method is autothermal reforming. In this case, a portion of the fuel is burned by the addition of oxygen within the reformer, so that the reaction gas is heated and the expiring endothermic reactions are supplied with heat.

Some proposals for internal heating of chemical reactors have become known in the art. For example, Zhang et al., International Journal of Hydrogen Energy 2007, 32, 3870-3879, describe the simulation and experimental analysis of a coaxial, cylindrical methane steam reformer using an electrically heated alumite catalyst (EHAC).

With regard to alternating operation, DE 10 2007 022 723 A1 and US 2010/0305221 describe a process for the production and conversion of synthesis gas, which is characterized in that it has a plurality of different operating states which essentially comprise the alternating (i) daytime operation and (ii) nighttime operation where the daily operation (i) mainly comprises dry reforming and steam reforming under the supply of regenerative energy and night operation (ii) mainly the partial oxidation of hydrocarbons and wherein the produced synthesis gas is used for the production of value products. US 2007/003478 Al discloses the production of synthesis gas with a combination of steam reforming and oxidation chemistry. The process involves the use of solids to heat the hydrocarbon feed and cool the gaseous product. According to this publication, heat can be conserved by reversing the gas flow of feed and product gases at intervals. WO 2007/042279 AI deals with a reformer system with a reformer for the chemical reaction of a hydrocarbon-containing fuel in a hydrogen gas-rich reformate gas, and electric heating means by which the reformer heat energy for producing a reaction temperature required for the feed can be supplied, wherein the reformer system further comprises a capacitor has, which can supply the electric heating means with electric current.

WO 2004/071947 A2 / US 2006/0207178 A1 relate to a system for the production of hydrogen, comprising a reformer for generating hydrogen from a hydrocarbon fuel, a compressor for compressing the hydrogen produced, a renewable energy source for converting a hydrogen renewable resource into electrical energy for driving the compressor and a storage device for storing the hydrogen from the compressor.

From what has been said above, it becomes clear that an economically sensible production of synthesis gas by utilizing regenerative energy sources places certain demands on the process procedure and the reactor used therein. On the one hand, an efficient electrical heating of the reactor, that is an efficient heat supply of the endothermic reaction must be realized. On the other hand, for phases in which no regeneratively generated energy is available, the possibility for other operation of the reactor should be present.

The object of the present invention is to provide such a method. In particular, it has set itself the task of specifying a method for the production of synthesis gas, which is suitable for an alternating operation between two different modes of operation.

This object is achieved by a method for the production of synthesis gas, comprising the steps a) providing a flow reactor, which is arranged for the reaction of a fluid comprising reactants, wherein the reactor comprises at least one heating level, which is electrically heated by means of one or more heating elements, wherein the heating level can be traversed by the fluid and at least one heating element, a catalyst is arranged and is heated there; b) setting a threshold value S l for the costs of the electrical energy available for the flow reactor and / or a threshold value S2 for the relative proportion of electrical energy from regenerative sources of the electrical energy available for the flow reactor and / or a threshold S3 for a desired ratio of hydrogen to carbon monoxide in the resulting synthesis gas; and c) comparing the costs of the electrical energy available for the flow reactor with the threshold value S l and / or the relative proportion of electrical energy from regenerative sources of the electrical energy available for the flow reactor with the threshold value S2 and / or the ratio from hydrogen too

Carbon monoxide in the resulting synthesis gas with the threshold S3; d) reaction of hydrocarbons with carbon dioxide and / or water in the flow reactor, wherein carbon monoxide and hydrogen are formed, with electric heating by one or more heating elements, when the threshold value S l falls below and / or the floating value S2 exceeded and / or the Threshold S3 be fallen below, wherein at least a portion of the hydrogen formed is fed to a storage and / or a reaction in another reactor is fed; e) Reaction of carbon dioxide with hydrogen in the flow reactor, wherein carbon monoxide and water are formed, under electrical heating by one or more heating elements, when the threshold value S 1 is exceeded and / or the threshold value S2 is exceeded and / or the threshold value S3 is exceeded in which at least part of the hydrogen used originates from the previously stored hydrogen and / or originates from a reaction in another reactor. In the method according to the invention for the alternate operation of a synthesis gas production, one determines which mode of operation is to be selected on the basis of one or more threshold values. The first threshold S l relates to the electricity costs for the reactor, in particular the cost of electrical heating of the reactor by the heating elements in the Fleizebenen. Here it can be determined to what extent the electric heating of the respective endothermic reaction is still economically reasonable.

The second threshold S2 relates to the relative proportion of electrical energy from regenerative sources available to the reactor and, in particular, to the electrical heating of the reactor by the heating elements in the heating levels. The relative proportion is in this case based on the total electrical energy of the electric current available for the flow reactor and can of course vary over time. Examples of regenerative sources from which electrical energy can be derived are wind, solar, geothermal, wave and hydro. The relative share can be determined by providing information to the energy supplier. If, for example, a plant's own regenerative energy sources such as solar power plants and wind turbines are used, this relative proportion of energy can also be indicated via performance monitoring.

The third threshold S3 relates to the requirements of the users of the synthesis gas in terms of its composition. Depending on your wishes, you can operate between an excess of hydrogen and a deficit.

Just as the threshold value S l can be understood as a price upper limit, for example, the visual threshold value S2 can be regarded as a requirement to use renewable energies to the greatest extent possible. For example, S2 may mean that from a proportion of 5%, 10%, 20% or 30% of electrical energy from renewable sources, the electrical heating of the reactor should take place.

A comparison of the desired values with the actual values in the method can now reach the conclusion that electrical energy is available inexpensively, enough electrical energy is available from renewable sources and / or the desired composition of the synthesis gas is maintained. Then the flow reactor is operated so that, for example, run a dry reforming reaction or a steam reforming reaction. The hydrocarbons involved are preferably alkanes, alkenes, alkynes, alkanols, alkenols and / or alkynols. Among the alkanes, methane is particularly suitable, among the alkanols methanol and / or ethanol are preferred. These reactions are exemplified below: Dry reforming of methane (DR): CH ₄ + C0 ₂ ^ 2 CO + 2H ₂

Steam reforming of methane (SMR): CH ₄ + IH) ^ 3 Hz + CO The dry reforming reaction of methane is strongly endothermic with +247 kJ / mol and the corresponding steam reforming reaction with +206 kJ / mol is also endothermic. Thus, the operation of the reactor requires comparatively much energy for the electrical heating.

If the target / actual comparison reveals that electrical energy is too expensive, too much energy should be used from non-regenerative sources and / or the synthesis gas has too high a hydrogen content, the operating mode of the flow reactor is changed and a reverse water gas shift Reaction takes place.

Reverse Water Gas Shift Reaction (RWGS): C0 ₂ + H ₂ ^ CO + IM ⁾

The RWGS reaction of methane is much less endothermic at +41 kJ / mol and is therefore suitable for times of high energy prices or too low a share of electrical energy from renewable sources.

Furthermore, as an additional heating method, the combustion of hydrogen can be used. It is both possible that the combustion of hydrogen in the RWGS reaction by metering of O2 into the educt gas (ideally, a locally distributed or lateral metering) takes place, as well as possible hydrogen-rich residual gases (for example, PSA exhaust gas), as be incurred in the purification of the synthesis gas, recycled and burned together with O2, which then the process gas is heated.

In general, endothermic reactions are heated from the outside through the walls of the reaction tubes. Opposite is the autothermal reforming with 02 addition. In the reactor operation described here, the endothermic reaction can be efficiently internally supplied with heat via an electrical heating within the reactor (the undesired alternative would be electrical heating via radiation through the reactor wall). This type of reactor operation is particularly economical if the excess supply resulting from the expansion of renewable energy sources can be used cost-effectively. In the process according to the invention, it is provided that during the hydrogen-forming reactions at least part of this hydrogen is fed to a storage and / or is fed to a reaction in another reactor. During the RWGS reaction, in which no hydrogen is currently being formed, the hydrogen required for the desired ifc / CO ratio can then be added again. The first option is to store the hydrogen withdrawn during the DR and SMR reactions in suitable storage tanks and then add it to the product of the RWGS reaction in an appropriate amount. The cheaper for a Verbund site under certain circumstances - in a variant, the extracted hydrogen is consumed in other reactions and, if necessary, is taken from hydrogen-producing reactions elsewhere in the Verbund site. Likewise, it is possible to feed the hydrogen into a central line of the site and to remove the required hydrogen from this line. The process according to the invention provides for the DR, SMR and RWGS reactions to proceed in the same reactor. A mixed operation of two or three of the reactions is expressly intended. One of the advantages of this approach is the gradual onset of the other reaction, for example, by continuously reducing the hydrogen supply while increasing the methane feed, or by continuously increasing the hydrocarbon feed while reducing the methane feed. Overall, the degree of endothermy can be set arbitrarily.

The present invention including preferred embodiments will be further explained in connection with the following drawings without being limited thereto. The forms of execution can be combined with each other as long as the opposite of the context is not clear.

FIG. 1 shows schematically a flow reactor in an expanded representation.

In one embodiment of the process according to the invention, the hydrogen is stored in pressure accumulators, in caverns, in the form of hydrides and / or in the form of organic compounds. Suitable pressure accumulators are, for example, pressure vessels, tube stores or pipelines. Suitable hydride compounds are especially elemental hydrogen compounds such as PtH ₂ , Mni l. CrH, TiH ₂ , VH ₂ , CrH ₂ and CeH ₂ , Mg ₂ NiH ₄ and / or Mg (BI U): With regard to the storage in the form of organic compounds in particular gaseous alkanes, alkenes and alkynes having 1 to 5 carbon atoms and liquid alcohols such as methanol and ethanol and organic acids (formic acid), ethers (dimethyl ether), aldehydes and ketones into consideration.

In a further embodiment of the process according to the invention, in the reaction of carbon dioxide with hydrogen, at least part of the hydrogen used originates from the electrolysis of water. In this way it can also be achieved that a sufficient amount of hydrogen is available during longer RWGS phases. The operating strategy of the water electrolysis can also be coupled to the parameters S l and S2: the electrolysis is carried out when the eleutische electric energy is cheap and / or if the proportion of electrical energy from renewable sources is large enough. This operating strategy yields an additional degree of freedom for the initial hydrogenation of RWGS phases. In a further embodiment of the method according to the invention, the flow reactor comprises in the flow direction of the fluid a plurality of heating levels, which are electrically heated by heating elements and wherein the heating levels are permeable by the fluid, wherein a catalyst is arranged on at least one heating element and is heatable there, wherein further at least once an intermediate plane between two heating levels is arranged and wherein the intermediate plane is also traversed by the fluid.

The in FIG. 1 schematically shown flow reactor used according to the invention is flowed through by a fluid comprising reactants from top to bottom, as shown by the arrows in the drawing. The fluid may be liquid or gaseous and may be single-phase or multi-phase. Preferably, also in view of the possible reaction temperatures, the fluid is gaseous. It is conceivable that the fluid contains only reactants and reaction products, but also that additionally inert components such as inert gases are present in the fluid. As seen in the direction of flow of the fluid, the reactor has a plurality of (four in the present case) heating levels 100, 101, 102, 103, which are electrically heated by means of corresponding heating elements 110, 111, 112, 13. The heating levels 100, 101, 102, 103 are flowed through during operation of the reactor of the fluid and the heating elements 1 10, 1 1 1, 1 12, 1 13 are contacted by the fluid. At least one heating element 1 10, 1 1 1, 1 12, 1 13, a catalyst is arranged and is heated there. The catalyst may be directly or indirectly connected to the heating elements 1 10, 1 1 1, 1 12, 1 13, so that these heating elements represent the catalyst support or a support for the catalyst support.

In the reactor, therefore, the heat supply of the reaction takes place electrically and is not introduced from the outside by means of radiation through the walls of the reactor, but directly into the interior of the reaction space. It is realized a direct electrical heating of the catalyst.

For the Fleizelemente 1 10, 1 1 1, 1 12, 1 13 are preferably Heizleiterlegierungen such as FeCrAl alloys used. In addition to metallic materials, it is also possible to use electrically conductive Si-based materials, particularly preferably SiC. In the reactor at least once more preferably a ceramic intermediate level 200, 201, 202 between two levels of fuel 100, 101, 102, 103 are arranged, wherein the intermediate level (s) 200, 201, 202 are also traversed by the fluid in the operation of the reactor. This has the effect of homogenizing the fluid flow. It is also possible that additional Catalyst in one or more intermediate levels 200, 201, 202 or further Isolationsseiementen in the reactor is present. Then an adiabatic reaction can take place. If necessary, the intermediate levels can act as a flame barrier, especially in the POX reaction. Said at least one intermediate ceramic layer is preferably supported by a ceramic or metallic support frame and / or a ceramic or metallic support plane.

When using FeCrAl heating conductors, the fact can be exploited that the material forms an AhC protective layer by the action of temperature in the presence of air / oxygen. This passivation layer can serve as a basecoat of a washcoat, which acts as a catalytically active coating. Thus, the direct resistance heating of the catalyst or the heat supply of the reaction is realized directly through the catalytic structure. It is also possible, when using other heating conductors, the formation of other protective layers such as Si-O-C systems. The pressure in the reactor can take place via a pressure-resistant steel jacket. Using suitable ceramic insulation materials it can be achieved that the pressure-bearing steel is exposed to temperatures of less than 200 ° C and, if necessary, less than 60 ° C. By means of appropriate devices, it can be ensured that, when the dew point is undershot, there is no condensation of water on the steel jacket. The electrical connections are shown in FIG. 1 only shown very schematically. They can be performed in the cold area of the reactor within an insulation to the ends of the reactor or laterally from the Heizel ementen 1 10, 1 1 1, 1 12, 1 13 performed so that the actual electrical connections can be provided in the cold region of the reactor can. The electrical heating is done with direct current or alternating current. By appropriate shaping an increase in surface area can be achieved. It is possible that in the heating levels 100, 101, 102, 103 heating elements 1 10, 1 1 1, 1 12, 1 13 are arranged, which are spirally, meandering, lattice-shaped and / or net-shaped.

It is also possible for at least one heating element 1 10, 11 1, 12, 13 to have a different amount and / or type of catalyst than the remaining heating elements 110, 11, 12, 13. Preferably, the heating elements 1 10, 1 1 1, 1 12, 1 13 are arranged so that they can each be electrically heated independently.

As a result, the individual heating levels can be individually controlled and regulated. In the reactor inlet area can be dispensed with a catalyst in the heating levels as needed so that only the heating and no reaction takes place in the inlet area. This is particularly advantageous in view of starting the reactor. If the individual heating levels 100, 101, 102, 103 differ in power input, catalyst charge and / or type of catalyst, a temperature profile adapted for the respective reaction can be achieved. With regard to the application for endothermic equilibrium reactions, this is, for example, a temperature profile which reaches the highest temperatures and thus the highest conversion at the reactor outlet.

The (for example ceramic) intermediate levels 200, 201, 202 or their contents 210, 21 1, 212 comprise a material resistant to the reaction conditions, for example a ceramic foam. They serve for mechanical support of the heating levels 100, 101, 102, 103 and for mixing and distribution of the gas stream. At the same time an electrical insulation between two heating levels is possible. It is preferred that the material of the content 210, 2 1 1, 212 of an intermediate level 200, 201, 202 comprises oxides, carbides, nitrides, phosphides and / or borides of aluminum, silicon and / or zirconium. An example of this is SiC. Further preferred is cordierite.

The intermediate level 200, 201, 202 may comprise, for example, a loose bed of solids and / or a one-piece porous solid. These solids themselves may be porous or solid, so that the fluid flows through gaps between the solids. The case of the one-piece porous solid is shown in FIG. 1 shown. The fluid flows through the intermediate plane via the pores of the solid. Preference is given to honeycomb monoliths, as used for example in the exhaust gas purification of internal combustion engines. It is preferred that the material of the solid bodies comprises oxides, carbides, nitrides, phosphides and / or borides of aluminum, silicon and / or zirconium. An example of this is SiC. Further preferred is cordierite. Another conceivable possibility is that one or more of the intermediate levels are voids.

With regard to the structural dimensions, it is preferred that the average length of a heating level 100, 101, 102, 103 is viewed in the direction of flow of the fluid and the average length of an intermediate level 200, 201, 202 in the direction of flow of the fluid is in a ratio of> 0.01: 1 to <100: 1 to each other. Even more advantageous are ratios of> 0, 1: 1 to <10: 1 or 0.5: 1 to <5: 1.

Suitable catalysts can be selected for example from the group consisting of: (I) mixed metal oxides of the formula A _(i-w-x) A 'A _"x B (iy _z) B' _y B" _z 03-Deita where:

A, A 'and A "are independently selected from the group: Mg, Ca, Sr, Ba, Li, Na, K, Rb, Cs, Sn, Sc, Y, La, Ce, Pr, Nd, Pm, Sm Lu, Gd, Tb, Dy, Ho, Er, Tm. Yb, i ^' l, Lu.

Ni, Co, Pb, Bi and / or Cd; and B, B 'and B "are independently selected from the group: Cr, Mn, Fe, Bi, Cd,

Co, Cu, Ni, Sn, Al. Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, I i f. Zr, Tb, W, Gd. Yb. Mg, Li. Na, K. Ce and / or Zn; and

0 <w <0.5; 0 <x <0.5; 0 <y <0.5; 0 <z <0.5 and -1 <deita <1;

(II) mixed metal oxides of the formula A (ΐ - "- _χ) Α" A _"x B B _'y B (i _{_y, z..)"} _Z 03-Deita which applies here:

A, A 'and A "are independently selected from the group: Mg, Ca, Sr, Ba, Li, Na, K. Rb, Cs, Sn, Sc, Y. La, Ce, Pr. Nd, Sm. Lu Gd, Tb, Dy. Ho, Er, Tm. Yb. Γ1, Lu, Ni,

Co, Pb and / or Cd; and

B is selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb. I i f. Zr. Tb. W, Gd. Yb. Mg, Cd, Zn, Re, Ru. Rh. Pd, Os, Ir and / or Pt; and

B 'is selected from the group: Re, Ru, Rh, Pd, Os, Ir and / or Pt; and

B "is selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb, II, Zr, Tb W, Gd, Yb, Mg, Cd and / or Zn; and

0 <w <0.5; 0 <x <0.5; 0 <y <0.5; 0 <z <0.5 and -1 <delta <1; (III) mixtures of at least two different metals Ml and M2 on a support comprising an oxide of Al, Ce and / or Zr doped with a metal M3; where:

Ml and M2 are independently selected from the group: Re, Ru, Rh, Ir, Os, Pd and / or Pt; and

M3 is selected from the group: Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, I lo, Er, Tm, Yb and / or Lu;

(IV) mixed metal oxides of the formula LO _x (M ( _y / _z ) Al (2- _y / z) 03) z; where:

L is selected from the group: Na, K, Rb. Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Pd, Mn, In,

Tl, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, I m. Yb and / or Lu; and

M is selected from the group: ^" I i, Zr, II for V, Nb, Ta, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Zn, Cu, Ag and / or Au, and

1 <x <2; 0 <y <12; and 4 <z <9;

(V) mixed metal oxides of the formula LO (AhO 3) z; where:

L is selected from the group: Na, K, Rb. Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Mn, In, Tl, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and / or Lu; and

4 <z <9;

(VI) Oxide catalyst comprising Ni and Ru.

(VII) metal Ml and / or at least two different metals Ml and M2 on and / or in a carrier, wherein the carrier is a carbide, oxycarbide, carbonitride, nitride, boride, silicide, germanide and / or selenium id of metals A and / or B is; where:

Ml and M2 are independently selected from the group: Cr, Mn, Fe, Co, Ni, Re, Ru, Rh, Ir, Os, Pd, Pt, Zn, Cu, La, Ce, Pr, Nd, Sm, Eu , Gd, Tb, Dy, FIo, Er, Tm, Yb, and / or Lu;

A and B are independently selected from the group: Be, Mg, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Y, Zr, Nb, Mo, I I f. Ta, W, La. Ce, Pr. Nd, Sm. Eu, Gd. Tb. Y. l io. He,

Tm, Yb, and / or Lu; and or

Reaction products of (I), (II), (III), (IV), (V), (VI) and / o of (VII) in the presence of carbon dioxide, hydrogen, carbon monoxide and / or water at a temperature of> 700 ° C.

The term "reaction products" includes the catalyst phases present under reaction conditions. Preferred are for:

(I) LaN OK; and or

(especially LaNio, gFeo, 203)

(II) LaNio, 9-o, 99Ruo, oi-o, iO3 and / or LnNo, 9-o, 99Rho, o ι -o, ιO3 (especially LaNio, 95Ruo, o503 and / or LaNio ^ sRho. oscB).

(III) Pt-Rh on Ce-Zr-Al oxide, Pt-Ru and / or Rh-Ru on Ce-Zr-Al oxide

(IV) BaNiAl _n Oi9, C a N i A I1 1O 19,

BaNio, 92Ruo, o8Ai nOi9, BaNio, 84Pto, i6A1 nOi9 and / or BaRuo.osA 1,95019

(V) BaA1i ₂ 0i9, SrAli ₂ 0 _{! 9} and / or CaAl _{! 2} 0i9

(VI) Ni and Ru on Ce-Zr-Al oxide, on an oxide of the class of perovskites and / or on an oxide of the class of hexaaluminates

(VII) Cr, Mn, Fe, Co, Ni, Re, Ru. Rh, Ir, Os, Pd, Pt, Zn, Cu, La, Ce, Pr, Nd, Sm, Hu. Gd, I b. Dy,

Ho, Er, Tm, Yb, and / or Lu on M0 ₂ C and / or WC.

The reactor according to the invention may be modular. A module may include, for example, a heating level, an intermediate level, the electrical contact and the corresponding further insulation materials and thermal insulation materials.

In the process according to the invention, an electric heating of at least one of the heating elements 110, 1111, 112, 13 takes place in the reactor provided. This can, but does not have to, be before the passage of a reactant through the flow reactor under at least partial reaction of the reactants of the fluid respectively.

The reactor can be modular. A module can contain, for example, a heating level, an insulation level, electrical contact, and the corresponding further insulation materials and thermal insulation materials.

As already mentioned in connection with the reactor, it is advantageous if the individual heating elements 110, 111, 112, 113 are operated with a respective different heating power.

With regard to the temperature, it is preferred that the reaction temperature in the reactor is at least in places> 700 ° C to <1300 ° C. More preferred ranges are> 800 ° C to <1200 ° C and> 900 ° C to <1100 ° C, The average (median) contact time of the fluid to a heating element 110, 111, 112, 113 may be for example> 0.01 seconds to <1 second and / or the average contact time of the fluid to an intermediate level 110, 111, 112, 113 may For example, be> 0.001 seconds to <5 seconds. Preferred contact times are> 0.005 to <1 second, more preferably> 0.01 to <0.9 seconds.

The reaction can be carried out at a pressure of> 1 bar to <200 bar. Preferably, the pressure is> 2 bar to <50 bar, more preferably> 10 bar to <30 bar.

Claims

Method for producing synthesis gas, comprising the steps: a) Providing a flow reactor which is set up to react a fluid comprising reactants, the reactor comprising at least one heating level (100, 101, 102, 103), which is heated by means of one or more heating elements ( 1 10,

111, 112, 113) is heated electrically, wherein the heating level (100, 101, 102, 103) can be flowed through by the fluid and at least one heating element (110, 111,

112, 113) a catalytic converter is arranged and can be heated there; b) determining a threshold value S l for the costs of the electrical energy available for the flow reactor and/or a threshold value S2 for the relative proportion of electrical energy from renewable sources of the electrical energy available for the flow reactor and/or a threshold value S3 for a desired ratio of hydrogen to carbon monoxide in the synthesis gas obtained; and c) comparing the costs of the electrical energy available for the flow reactor with the threshold value S1 and/or the relative proportion of electrical energy from renewable sources of the electrical energy available for the flow reactor with the threshold value S2 and/or the ratio of Hydrogen to carbon monoxide in the synthesis gas obtained with the threshold value S3; d) Reaction of hydrocarbons with carbon dioxide and/or water in the flow reactor, whereby carbon monoxide and hydrogen are formed, under electrical heating by one or more heating elements (110, 111, 112, 113), if the threshold value Sl is undershot and/or the threshold value S2 is exceeded and/or the threshold value S3 is not reached, with at least part of the hydrogen formed being fed to storage and/or fed to a reaction in another reactor; e) reaction of carbon dioxide with hydrogen in the flow reactor, whereby carbon monoxide and water are formed, under electrical heating by one or more heating elements (110, 111, 112, 113) when the threshold value S1 is exceeded and/or the threshold value S2 is undershot and / or the threshold value S3 is exceeded, with at least part of the hydrogen used comes from previously stored hydrogen and/or comes from a reaction in another reactor.

2. The method according to claim 1, wherein the hydrogen is stored in pressure accumulators, in caverns, in the form of hydrides and / or in the form of organic compounds.

3. The method according to claim 1 or 2, wherein in the reaction of carbon dioxide with hydrogen at least part of the hydrogen used comes from the electrolysis of water.

4. The method according to any one of claims 1 to 3, wherein the flow reactor, viewed in the flow direction of the fluid, comprises a plurality of heating levels (100, 101, 102, 103), which are provided by means of heating elements (1 10, 1 1 1, 1 12, 1 13 ) are electrically heated and wherein the fluid levels (100, 101, 102, 103) can flow through, a catalyst being arranged on at least one heating element (100, 101, 102, 103) and being heated there, furthermore at least once a ceramic intermediate level (200, 201, 202) is arranged between two heating levels (100, 101, 102, 103) and the fluid can also flow through the intermediate level (200, 201, 202).

5. The method according to claim 4, wherein in the heating levels (100, 101, 102, 103) heating elements (1 10, 1 1 1, 1 12, 1 13) are arranged, which are spiral, meandering. have a grid-shaped and/or net-shaped structure.

6. The method according to claim 4 or 5, wherein at least one heating element (1 10, 1 1 1, 1 12, 1 13) has a different amount and from the other heating elements (1 10, 1 1 1, 1 12, 1 13). /or type of catalyst is present.

7. The method according to any one of claims 4 to 6, wherein the heating elements (1 10, 1 1 1, 1 12, 1 13) are set up so that they can each be electrically heated independently of one another.

8. The method according to any one of claims 4 to 7, wherein the material of the content (210, 21 1, 212) of an intermediate level (200, 20 1, 202) is oxides, carbides, nitrides, phosphides and / or borides of aluminum, silicon and / or zirconium.

9. The method according to any one of claims 4 to 8, wherein the intermediate level (200, 201, 202) comprises a loose bed of solids and / or a one-piece porous solid.

10. The method according to any one of claims 4 to 9, wherein the average length of a heating level (100, 101, 102, 103) viewed in the flow direction of the fluid and the average length of an intermediate level (200, 201, 202) viewed in the flow direction of the fluid have a ratio of > 0.01: 1 to < 100: 1 to each other. 11. The method according to any one of claims 1 to 10, wherein the catalyst is selected from the group consisting of:

(I) Mixed metal oxides of the formula A (i- _w -x)A ^! _w A" _x B(i. _y . _z )B' _y B" _z 03-deita where the following applies:

A, A' and A" are independently selected from the group: Mg, Ca, Sr, Ba, Li, Na, K, Rb, Cs, Sn, Sc, Y, La. Ce, Pr, Nd, Pm, Sm , hu. Gd, Tb, Dy, Ho, Er, i m. Yb, Tl , Lu, Ni, Co, Pb, Bi and/or Cd; and

B, B' and B" are independently selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn. Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb Hf, ZR, Tb. W, Gd. Yb, Mg, Li, Na, K, Ce and/or Zn; and 0 <0.5; 0 <x <0.5; 0 <0.5; 0 <z < 0.5 and - 1 < delta < I ;

(II) Mixed metal oxides of the formula A (i. _w -x)A' _w A" _x B(i- _y - _z )B' _y B" _z 03-deita where the following applies:

A, A' and A" are independently selected from the group: Mg, Ca, Sr, Ba. Li. Na, K. Rb, Cs, Sn, Sc, Y. La, Ce, Pr, Nd, Sm, Eu , Gd. Tb. Dy, Ho, Er, im. Yb. Tl , Lu, Ni, Co, Pb and/or Cd; and

B is selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti, V, Nb, Ta, Mo, Pb. I i f. Zr, Tb, W, Gd. Yb. Mg, Cd. Zn. Re, Ru. Rh. Pd, Os, ir and/or Pt; and

B' is selected from the group: Re, Ru, Rh, Pd, Os, Ir and/or Pt; and B" is selected from the group: Cr, Mn, Fe, Bi, Cd, Co, Cu, Ni, Sn, Al, Ga, Sc, Ti,

V, Nb, Ta, Mo, Pb, Hf, Zr, Tb. W. Gd, Yb. Mg, Cd and/or Zn: and

0<w<0.5;0<x<0.5; 0 < y <0.5; 0 < z < 0.5 and - I < delta <1; (III) mixtures of at least two different metals M 1 and M2 on a support comprising an oxide of Al, Ce and/or Zr doped with a metal M3; where the following applies here: Ml and M2 are independently selected from the group: Re, Ru, Rh, Ir,

Os, Pd and/or Pt; and

M3 is selected from the group: Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er,

Tm, Yb and/or Lu;

(IV) mixed metal oxides of the formula LO _x (M( _y / _z )Al(2-y/z)03)z; where the following applies here:

L is selected from the group: Na, K, Rb, Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Pd, Mn, In, Tl. La, Ce, Pr, Nd, Sm. Eu , Gd, Tb, Oy. Ho, Er, Tm. Yb and/or Lu; and

M is selected from the group: Ti, Zr,

1 1 f , V, Nb, l ^' a, Cr, Mo, W, Mn, Re, Fe, Ru, Os, Co, Rh. Ir, Ni, Pd. Pt. Zn, Cu, Ag and/or Au; and 1 < x <2; (X y < 1 2; and 4 < z <9;

(V) mixed metal oxides of the formula LO(A1i03) _z ; where the following applies here:

1. is selected from the group: Na, K. Rb. Cs, Mg, Ca, Sr, Ba, Sc, Y, Sn, Pb, Mn,

In, Tl, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and/or Lu; and 4 < z < 9;

(VI) oxide catalyst comprising Ni and Ru.

(VII) metal Ml and/or at least two different metals Ml and M2 on and/or in a carrier, the carrier being a carbide, oxycarbide, carbonitride, nitride, boride, silicide, germanide and/or selenide of the metals A and/or Are; where the following applies here: Ml and M2 are independently selected from the group: Cr, Mn, Fe, Co, Ni, Re, Ru. Rh, Ir, Os, Pd, Pt, Zn, Cu, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb. Dy, Ho, Er, I m, Yb, and/or Lu; and

A and B are independently selected from the group: Be, Mg, Ca, Sc, I i, V, Cr, Mn, Fe, Co, Ni, Y, Zr, Nb, Mo, I I f. Ta, W, La , Ce, Pr. Nd, Sm, Eu, Gd, Tb.

Dy, Ho, Er, Tm, Yb, and/or Lu; and or

Reaction products of (I), (II), (III), (IV), (V), (VI) and/or (VII) in the presence of carbon dioxide, hydrogen, carbon monoxide and/or water at a temperature of > 700 ° C

12. The method according to any one of claims 4 to 1 1, wherein the individual heating elements (1 10,

1 1 1 , 112, 1 13) can be operated with a different heating output.

13. The method according to any one of claims 1 to 12, wherein the reaction temperature in the reactor is at least in places >700 °C to <1300 °C.

14. The method according to any one of claims 4 to 13, wherein the average contact time of the fluid to a heating element (1 10, 1 1 1, 1 12, 1 13) is > 0.001 seconds to < 1 second and / or the average contact time of the fluid to an intermediate level (1 10, 1 1 1 ,

1 12, 113) > 0.001 seconds to < 5 seconds.

15. The method according to any one of claims 1 to 14, wherein the selected reaction is carried out at a pressure of >1 bar to <200 bar.