SYSTEM NETWORK AND METHOD FOR OPERATING A SYSTEM NETWORK OF THIS TYPE FOR PRODUCING HIGHER ALCOHOLS

Abstract

A plant complex may include a unit that produces CO.sub.2-containing gases, a gas conducting system for CO.sub.2-containing gases, a gas/liquid separation system, a reformer that is connected to the gas conducting system and where the CO.sub.2-containing gas reacts with H.sub.2 and/or hydrocarbons to give a CO— and H.sub.2-containing synthesis gas mixture. The reformer is connected to a reactor for producing higher alcohols in which the synthesis gas mixture reacts with H.sub.2 to give a gas/liquid mixture containing higher alcohols. For separating off the alcohols of the gas/liquid mixture, the gas/liquid separation system is connected to the reactor for producing higher alcohols.

Claims

1.-15. (canceled)

16. A plant complex comprising: a unit that produces CO.sub.2-containing gases; a gas conducting system for CO.sub.2-containing gases; a gas/liquid separation system; and a reformer that is connected to the gas conducting system, wherein the reformer is configured so that the CO.sub.2-containing gases react with H.sub.2 and/or hydrocarbons in the reformer to give a CO— and H.sub.2-containing synthesis gas mixture, the reformer being connected to a reactor for producing higher alcohols in which the synthesis gas mixture reacts with H.sub.2 to give a gas/liquid mixture containing higher alcohols, wherein for separating off the alcohols of the gas/liquid mixture, the gas/liquid separation system is connected to the reactor for producing higher alcohols.

17. The plant complex of claim 16 wherein the unit comprises a blast furnace configured to produce pig iron and a converter steel works configured to produce crude steel, wherein the gas conducting system conducts gases formed in the production of pig iron and/or gases formed in the production of crude steel.

18. The plant complex of claim 17 wherein the unit comprises a coke-oven plant, wherein the gas conducting system includes a gas distribution for coke-oven gas that is formed in a coking process in the coke-oven plant.

19. The plant complex of claim of claim 16 comprising a gas compression unit.

20. The plant complex of claim 16 comprising a gas purification unit.

21. The plant complex of claim 16 wherein the gas/liquid separation system is configured to separate off alkanes and alkenes of the gas/liquid mixture.

22. The plant complex of claim 16 wherein the gas/liquid separation system includes a recycle conduit connected to the reformer that is configured to return, into the reformer, gas components including CO, CO.sub.2, H.sub.2, and methane that are present in the gas/liquid mixture as reactants and by-products.

23. The plant complex of claim 22 comprising a pressure swing adsorption unit that is connected to an outlet for discharge of synthesis residual gas, wherein the pressure swing adsorption unit is configured to recover H.sub.2 by pressure swing adsorption and then recycle the H.sub.2 into the reformer and/or the reactor for producing higher alcohols.

24. The plant complex of claim 16 comprising: a second unit that is downstream of the gas/liquid separation system and is configured to separate the alcohols from the hydrocarbons; a hydration unit that is connected to the second unit and is configured to convert alkenes to alcohols; and an alcohol/alkane separation device, wherein the hydration unit is connected to the alcohol/alkane separation device, wherein the hydration unit and the alcohol/alkane separation device are configured such that the alcohols obtained by hydration are separated off from the alkanes and unconverted alkenes to be recycled into the plant.

25. A process for producing higher alcohols from CO.sub.2-containing gases with a plant complex comprising a unit that produces CO.sub.2-containing gases, a gas conducting system for CO.sub.2-containing gases, a reformer, a reactor for producing higher alcohols, and a gas/liquid separation system, wherein the process comprises: V1) reacting hydrocarbons with the CO.sub.2-containing gases and/or CO.sub.2 and/or O.sub.2 and/or H.sub.2O as oxygen sources to give a CO— and H.sub.2-containing synthesis gas mixture in the reformer; V2) reacting the synthesis gas mixture with H.sub.2 to give a gas/liquid mixture containing higher alcohols in the reactor for producing higher alcohols; and V3) separating off liquid alcohols of the gas/liquid mixture in the gas/liquid separation system from gas components.

26. The process of claim 25 comprising: recovering the H.sub.2 present in the synthesis residual gas by pressure swing adsorption in a pressure swing adsorption unit; and supplying the H.sub.2 to the reformer and/or to the reactor for producing higher alcohols.

27. The process of claim 25 comprising: obtaining H.sub.2 from compressed coke-oven gas by pressure swing adsorption in a pressure swing adsorption unit; and supplying the H.sub.2 to the reformer and/or to the reactor for producing higher alcohols.

28. The process of claim 25 comprising operating the reformer in a temperature range from 600° C. to 1200° C.

29. The process of claim 25 comprising separating alkanes and alkenes of the gas/liquid mixture off in the gas/liquid separation system.

30. The process of claim 25 wherein after separating off liquid alcohols of the gas/liquid mixture in the gas/liquid separation system from gas components, the process comprises separating the alcohols from the hydrocarbons and supplying the hydrocarbons to a hydration unit where alkenes are converted to alcohols, wherein in an alcohol/alkane separation device the alcohols obtained by hydration are then separated off from alkanes and unconverted alkenes to be recycled into the process.

Description

[0048] The invention is described below on the basis of exemplary embodiments with reference to the enclosed drawings. In the figures:

[0049] FIG. 1: A schematic diagram of a plant complex according to the invention,

[0050] FIG. 2: A schematic diagram of a further plant complex according to the invention,

[0051] FIG. 3: A schematic diagram of a further plant complex according to the invention, and

[0052] FIG. 4: A schematic diagram of the process according to the invention.

[0053] In the various figures, identical parts are always provided with the same reference signs and are therefore also generally each named or mentioned only once.

[0054] FIG. 1 shows an example of a plant complex 1 according to the invention, in which CO.sub.2-containing gases C from a unit that produces CO.sub.2-containing gases are brought in a gas compression unit 2 to a pressure that is predeterminable for the following processes, in order thereby to be able to adjust the reaction rate for the following chemical reactions. Then, in a gas purification unit 3, the compressed CO.sub.2-containing gases are purified of chemical substances that impair the catalyst of the reactor for producing higher alcohols in terms of its functioning and service life, in particular cyanides and sulfur and ammonium compounds.

[0055] Hydrocarbons then react with the CO.sub.2-containing gases C and/or CO.sub.2 and/or O.sub.2 and/or H.sub.2O as oxygen sources to give a CO— and H.sub.2-containing synthesis gas mixture in a reformer 4. The synthesis gas produced by the reformer 4 and for the production of the higher alcohols contains CO and CO.sub.2. It is a particular advantage that, when using the reformer 4, it can be used to adjust the equilibrium of the reverse water-gas shift reaction. Optimally, this is shifted to the product side, so that a particularly high conversion of the CO.sub.2, for example from smelter gases, to CO is achieved, which in turn improves the efficiency of the synthesis of higher alcohols. The adjustment of the equilibrium of the reverse water-gas shift reaction, so as to achieve a particularly high conversion of the CO.sub.2 to CO, is achieved in a particularly advantageous manner in the plant complex 1 according to the invention by operating the reformer 4 in a temperature range from 600 to 1200° C., in particular 1050 to 1150° C.

[0056] After the synthesis gas mixture has been produced in the reformer 4 with the highest possible content of CO, it is catalytically reacted, in a reactor for producing higher alcohols 5, with H.sub.2 to give a gas mixture containing higher alcohols, whereupon this gas mixture is separated into a liquid phase and a gas phase.

[0057] Subsequently—as is also shown in FIG. 1—the gas/liquid mixture for separating off the alcohols is passed into a gas/liquid separation system 6 which is connected to the reactor 5 and in which the higher alcohols, in particular ethanol, propanol and butanol, are separated off and in a downstream distillation unit 7 are separated into their individual constituents.

[0058] The gas/liquid separation system 6 has a gas recycle conduit connected to the reformer for returning the gas components of the gas/liquid mixture, in order to recycle the gas components G to further improve the carbon efficiency.

[0059] In the plant complex illustrated in FIG. 1, the H.sub.2 for the reformer 4 and the reactor for producing higher alcohols 5 is provided, inter alia, via H.sub.2 recovery in a pressure swing adsorption unit 8 from the synthesis residual gas P departing the reformer 4, which is separated off from the gas components G, in order to reduce the dependence on external H.sub.2 sources and increase the H.sub.2 self-sufficiency.

[0060] Particular preference with regard to minimizing the dependence on external H.sub.2 sources is given, in accordance with the further-developed plant complex according to the invention illustrated in FIG. 2, to providing the H.sub.2 for the reformer 4 and the reactor for producing higher alcohols 5 via the purification/obtaining of the H.sub.2 from coke-oven gas (H.sub.2-rich) K by means of H.sub.2 recovery (pressure swing adsorption) and also the recovery of H.sub.2 from the synthesis residual gas P.

[0061] FIG. 3 shows a further preferred configuration of the plant complex according to the invention. In this plant complex, connected upstream of the reactor for producing higher alcohols 5 is an additional reactor for optimizing/fine-tuning the synthesis gas composition 4a, in which in particular the equilibrium of the water-gas shift reaction can be adjusted, as a result of which the efficiency when producing higher alcohols can be further improved. In addition, this plant complex according to the invention has a further stage by means of which separation of the alcohols from the hydrocarbons is made possible, for example a distillation unit 7. The hydrocarbons separated off are supplied to a hydration unit 9 in which the alkenes are converted to alcohols. The alcohols obtained by the hydration are then separated off from the alkanes and unconverted alkenes to be recycled into the process in an alcohol/alkane separation device 10. The alkanes and alkenes are preferably recycled by introduction into the reformer.

[0062] FIG. 4 shows a schematic diagram of the process according to the invention. In process step V0a, for protecting the catalyst disposed in the reactor for producing higher alcohols, aggressive constituents of the CO.sub.2-containing gases, in particular cyanides and sulfur or ammonium compounds, are removed in the gas purification unit in order to increase the service life of the catalyst located in the reactor for producing higher alcohols. Subsequently, the CO.sub.2-containing gases are brought to a defined pressure V0b in a gas compression unit in order to be able to perform the following process steps optimally. A multiplicity of different compressors may also be provided, since the gas purification and the gas synthesis proceed at different pressures. The CO.sub.2-containing gases are then reacted in the reformer 4 with H.sub.2 and/or hydrocarbons to give a CO— and H.sub.2-containing synthesis gas mixture, which is then passed into the reactor for producing higher alcohols 5. Finally, the alcohols A of the gas/liquid mixture in the gas/liquid separation system 6 are separated off from the gas components.

LIST OF REFERENCE SIGNS

[0063] 1 Plant complex [0064] 2 Gas compression unit [0065] 3 Gas purification unit [0066] 4 Reformer [0067] 4a Reactor for adjusting the synthesis gas composition [0068] 5 Reactor for producing higher alcohols [0069] 6 Gas/liquid separation system [0070] 7 Distillation unit [0071] 8 Pressure swing adsorption unit [0072] 9 Hydration unit [0073] 10 Alcohol/alkane separation device [0074] A Alcohols, alkanes, alkenes [0075] Alk Alcohols [0076] C CO.sub.2-containing gases [0077] G Gas components [0078] H H.sub.2 [0079] K Coke-oven gas [0080] P Synthesis residual gas [0081] V0a Gas purification [0082] V0b Gas compression [0083] V1 Reaction of the CO.sub.2-containing gases to give synthesis gas mixture [0084] V2 Reaction of the synthesis gas mixture to give a gas/liquid mixture containing higher alcohols [0085] V3 Separating-off of the liquid higher alcohols