The invention relates to a method for producing a synthetic material, in particular a synthetic fuel or raw material. The invention also relates to the associated device for carrying out the method and to applications of this device in different sectors of industry.
The invention relates both to the production of synthetic fuels (synfuel) and to the production of synthetic raw materials for the chemical industry. Such production methods require energy on the one hand and also, as a basis for the material, hydrogen (H2), oxygen (O2) and carbon (C). In such cases wind or other renewable energies are used in particular, with CO2 incident in other industrial processes also able to be recycled as the basis for the materials.
The changes in the crude oil price as well as in the natural gas price linked to it, stagnating oil production and the prospect of reserves becoming exhausted over the medium term reveal a shortage of these raw materials which is becoming ever greater, which is especially reflected in rising prices. This equally demands the development of environmentally-friendly resources, especially renewable energy generation, i.e. wind and/or solar energy. For wind energy in particular there are currently plans for extensive wind farms, especially also offshore farms. These thus provide sources of electrical energy of which at specific times the energy is not needed.
Previous wind energy was fed exclusively into the power grid, with hydraulic storage (pump storage or pneumatic storage (compressed air/gas stores) being possible as an alternative. The interesting aspect in this context is also the recycling of the wind energy in so-called redox storage, with chemical storage and batteries/rechargeable cells possibly being used for this purpose.
As far as chemical storage is concerned, conversion of the electrical energy generated with wind energy into hydrogen (H2) or furthermore a conversion into methane (CH4) or finally a conversion into higher hydrocarbons is possible. This includes synthetic fuels, which are generally referred to as synfuel.
Apart from the above, an increase in chemical costs is also expected as the oil/gas price increases. This produces competition between energy and raw material supply. To take account in particular of the price increase in raw material costs, a cost-effective conversion of wind energy into chemical raw materials can offer a new perspective.
For wind-chemistry conversion the wind is the decisive energy source, with an associated material source being available through carbon from biomass and/or carbon from carbon-dioxide recycling. Carbon-dioxide recycling in particular is of particular significance because of the global warming.
An object of the invention is to specify methods with which materials can be created in a suitable manner as well as creating the associated devices. In addition different applications of relevance for industrial practice are to be proposed.
The object is achieved by a method, a device and applications according to the independent claims. Developments of the method, the associated device and the specific applications are the subject matter of the dependent claims.
A suitable method is specified by the invention with which synthetic materials can be created from electrical energy or power, especially generated using wind. These materials are principally gaseous, can on the one hand be synthetic fuels (synfuel) similar to known GTL (Gas To Liquid) conversion or reversal of steam reforming (=methanation) but on the other hand can also be raw materials for the chemical industry. A carbon basis is needed for the creation of such materials, for which purpose the exhaust gases containing CO2 incident in industrial processes are now used. To this extent the invention is also suitable as an approach to resolving current questions concerning environmentally correct handling of CO2 and ameliorating the global climate problem.
The particular advantage of the invention is that, especially with the use of surplus power generated in an environmentally-friendly way, i.e. without a separate CO2 burden, and recycling of CO2 otherwise present as waste gas, the overall CO2 balance of the inventively-created synthetic materials can be improved.
The invention makes use in a particular way of the chemistry of water electrolysis. The following chemical processes take place in such chemistry:
2H2O.2H2+O2 (1)
The electrical energy is employed for electrolytic decomposition of the water. This is followed by a catalytic reaction, similar to the standard method used in GTL conversion or the reversal of the steam reforming reaction (=methanation):
4H2+CO2.CH4+2H2O (2)
Carbon dioxide can be recycled from biogenic sources or separately from industrial waste gases in the catalytic process:
(3n+1)H2+nCO2.CnH2n+2+2nH2O (3)
The latter process products, as liquid hydrocarbons, are suitable raw materials for the chemical industry. Depending on how the catalytic process is conducted, functionalized hydrocarbons such as for example alcohols, carbonic acids, ketones, aldehydes, cyclic or aromatic compounds and many more can also be isolated.
These hydrocarbons can feature both aliphatic (straight-chain, branched) and also aromatic (also hetero and polyaromatic systems), saturated and (simple/multiple) unsaturated (e.g. olefinic, etc.) structures as well as possessing structure elements generally functionalized by heteroatoms (especially O, N, S, Halogen, Si), e.g. alcohols, aldehydes, ketones, carbonic acids, amines, amides, thioles, thiocarbonic acids, esters, amino acids, heteroaromatics and many more, as well as combinations of the number of functionalities which can be derived from the specified heteroatoms, in one product molecule.
The invention makes available the above-mentioned material conversion process (similar to GTL or methanation) in a cost-effective manner in which synthetic hydrocarbons are generated as the result of gasification and the known Fischer-Tropsch synthesis, which can be used as diesel fuel or also as benzine for example. In such cases an economic procedure appears conceivable since a comparatively low degree of carbon neutralization ηc is realized. Apart from this an ecological procedure also appears to be produced, the CO2 emissions are higher than for refinery products and can be recycled accordingly.
Further details and advantages of the invention emerge from the description of FIGURE-based exemplary embodiments given below which refer to the drawing in conjunction with the claims.
The single FIGURE shows a schematic diagram of the conversion of electrical energy using a high-temperature electrolysis to generate synthetic materials, for example synthetic fuel, or other raw materials.
Labeled 1 in the FIGURE is a unit for generating electrical energy. This electrical energy is provided especially in accordance with unit 1a by wind energy converters. It can however also be provided in the form of solar energy in accordance with unit 1b, or in accordance with unit 1c also in another form, generally purchased on an electricity exchange for example.
The electrical energy is given to a unit 2 for high-temperature electrolysis (other electrolyzers (PEM/alkali) are also conceivable but not so effective). Connected downstream from the unit 2 are a catalytic reactor 3 and a further unit 4 for conditioning the materials created.
In the unit 2 for high-temperature electrolysis hydrogen (H2) and oxygen (O2) is created from water (H2O). The CO2 from a CO2-source 5 is now added to the end product. Through the reaction of hydrogen and the added CO2, CH4 and water are produced in accordance with the reaction equations below:
Water electrolysis: .2H2O.2H2+O2
Electrical energy is used for electrolytic decomposition of the water.
Catalytic reaction • standard method for methanation:
4H2+CO2.CH4+2H2O
The carbon dioxide from biogenic sources or separately from waste gases is recycled in the catalytic process.
(3n+1)H2+nCO2.CnH2n+2+2nH2O
The products thus created are liquid hydrocarbons, but gaseous and solid hydrocarbons are also conceivable in pure and also in functionalized form (see above), suitable as raw materials for the chemical industry.
An advantageous method of carbon recycling and the reduction/avoidance of the CO2 emissions thus emerges by comparison with (and differentiated from) the known GTL process. Unlike in the GTL method, in the method proposed here, CO2 is not released but is consumed.
Computations have been carried out which demonstrate the economic prospects of conversion of wind energy into synthetic materials. The results of these have been that, with the current high oil price, a cost-effective conversion of wind energy into synthetic materials is possible under certain conditions. The cost effectiveness of the method presented is heavily dependent on the market prices of the primary energy carriers, such as oil and natural gas.
In the event of the power source for the high-temperature electrolysis being implemented by using wind energy it can be shown that with a rise in the oil price an economic conversion of the energy into new materials is produced. Thus the objective of energetic/synthetic recycling of separated carbon dioxide on the one hand and ensuring raw materials for the chemical industry on the other hand is achieved. In particular in addition to the raw materials, the materials created can also be fuels which can be used as fuel for motor vehicles and the like.
Overall a reduction of CO2 emissions by comparison with the known GTL process occurs with the proposed processes. CO2 is not released but consumed. As well as the creation of the synthetic materials, the method is thus suitable for ensuring processing of the CO2 arising in many industries which otherwise has negative global effects as a climate-damaging gas.
Number | Date | Country | Kind |
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10 2008 053 334.3 | Oct 2008 | DE | national |
This application is the US National Stage of International Application No. PCT/EP2009/064090 filed Oct. 26, 2009, and claims the benefit thereof. The International Application claims the benefits of German Application No. 10 2008 053 334.3 DE filed Oct. 27, 2008. All of the applications are incorporated by reference herein in their entirety.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2009/064090 | 10/26/2009 | WO | 00 | 6/28/2011 |