GB2504098A

GB2504098A - Synthesis plant for production of organic fuels from carbon dioxide and water using solar energy

Info

Publication number: GB2504098A
Application number: GB1212677.7A
Authority: GB
Inventors: David Andrew Johnston
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-07-17
Filing date: 2012-07-17
Publication date: 2014-01-22
Also published as: GB201212677D0

Abstract

A solar concentrator (1) is used to provide energy to a gas turbine (2). This drives an electrical generator (3), the electricity from which is used in an electrolyser (4) to produce hydrogen (5) from water. Carbon dioxide is captured from the atmosphere using an absorber (8), and fed into a fuel synthesis plant (11) together with the hydrogen (5), where these are used to form synthesis gas, and then a range of hydrocarbons (12) or alcohols (13). Recovered heat (6 and 14) and supplementary solar heating (7) may be used to pre-heat the water in the electrolyser (4).

Description

Synthesis Plant for Production of Organic Fuels from Carbon Dioxide and Water Using Solar Energy This invention relates to a production plant for organic fuels, in which solar energy is used to produce hydrogen, which then reacts with carbon dioxide to form synthesis gas (a mixture of carbon monoxide and hydrogen). This is then converted, via the Fischer-Tropsch process, to a range of hydrocarbons and alcohols.

Petroleum oil is a limited resource, which will become more difficult and costly to extract as reserves become depleted. The difficulties in extraction may limit production to the point where it cannot meet increasing demand. An alternative source of oil, in the medium term, is coal-to-liquid (CTL) synthesis. This however will increase coal production, over and above that required to meet increasing demand for other applications -electricity generation, iron and steel production, etc. Consequently, coal reserves will become depleted sooner than would otherwise be the case.

Furthermore, combustion of both coal and oil, as well as the synthesis of oil from coal, produce carbon dioxide, which is the single largest contributor to global warming.

The Fischer-Tropsch process, used in coal-to-liquid synthesis, can be modified to produce hydrocarbons and alcohols from water and atmospheric carbon dioxide. There are a number of chemical pathways in the initial stages, each of which results in the production of synthesis gas.

One of these is to produce hydrogen from water, typically by electrolysis, and use some of this to form carbon monoxide by reversing the shift reaction. The synthesis gas is then used to form hydrocarbons and alcohols using the same as for Fiseher-Tropsch coal-to-liquid synthesis. The production of hydrogen requires an input of energy. In order that this type of fuel synthesis be sustainable and carbon neutral, the source of energy should be renewable. Solar energy is the most widely considered choice for this purpose.

The present invention is described with reference to Figure 1.

An optical concentrator (1) focuses solar radiation to heat gas in a gas turbine (2). This is used to power an electrical generator(3). The electricity generated is supplied to an electrolyser (4), which electrolyses water to produce hydrogen (5). Optionally, waste heat (6) from the turbine, and a supplementary optical concentrator (7) can be used to pre-heat the water. An absorber (8) extracts carbon dioxide (9) from the atmosphere. This may be placed in storage (10) for later use, or transferred to a fuel synthesis plant (11), together with hydrogen (5) from the electrolyser (4), for production of synthesis gas and subsequent production of hydrocarbons (12) or alcohols (13). Heat (14) recovered from energy-releasing reactions in this plant (11) may be transferred to the electrolyser (4), to further pre-heat the water.

Claims

Claims 1. An organic fuel synthesis plant, wherein solar energy is used to produce organic fuels from water and carbon dioxide.
2. An organic fuel synthesis plant, as claimed in Claim 1, wherein a solar thermal engine is used to generate electricity for the electrolytic production of hydrogen from water.
3. An organic fuel synthesis plant, as claimed in Claim I and Claim 2, wherein optical concentrators are used to provide the solar energy input for the solar thermal engine.
4. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3, wherein the optical concentrators are in the form of mirrors.
5. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3, wherein the optical concentrators are in the form of lenses.
6. An organic fuel synthesis plant, as claimed in Claim I and Claim 2 and Claim 3, wherein the optical concentrators include prisms.
7. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3, wherein the optical concentrators include windows.
8. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3, and as claimed in Claim 4 or Claim 5 or Claim 6 or Claim 7, wherein the optical concentrators include some or all of these components.
9. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3, wherein the solar thermal engine is in the form of a gas turbine.
10. An organic fuel synthesis plant, as claimed in Claim 1 atd Claim 2 and Claim 3 and Claim 9, wherein the solar thermal engine includes reheat in the turbine stages.
11. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3 and Claim 9, wherein the solar thermal engine includes recuperation of heat between the return flow and the heating chamber.
12. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3 and Claim 9, wherein the solar thermal engine includes intercooling in the compressor stages.
13. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 3 and Claim 9, and Claim 10 or Claim 11 or Claim 12, wherein the solar thermal engine includes some or all of these components.
14. An organic fuel synthesis plant, as claimed in Claim I and Claim 2, wherein heat recovered from the solar thermal engine is used to pre-heat the water.
15. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2, wherein a solar photovoltaic array is used to generate electricity for the electrolytic production of hydrogen from water.
16. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 14, wherein high temperature electrolysis is employed.
17. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 14 and Claim 16, wherein the water is in the form of vapour or gas (steam).
18. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 14 and Claim 16 and Claim 17, wherein a solid electrolyte is used.
19. An organic fuel synthesis plant, as claimed in Claim I and Claim 2, wherein a means is provided for extraction of carbon dioxide from the atmosphere.
20. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2, wherein carbon dioxide is derived from the exhaust gases of other industrial processes.
21. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 20, wherein the industrial process involves the combustion of fossil fuels.
22. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 20, wherein the industrial process is the production of cement or concrete.
23. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2, wherein the carbon dioxide is extracted from a storage facility, wherein the carbon dioxide was initially derived from the industrial processes described in Claim 19 or Claim 20 or Claim 21 or Claim 22.
24. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2, and Claim 19 or Claim or Claim 21 or Claim 22 or Claim 23, wherein the carbon dioxide is derived from some or all of these sources.
25. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2, wherein the carbon dioxide and some of the hydrogen are used to produce carbon monoxide, such that the resulting mixture consists of carbon monoxide and hydrogen, also known as synthesis gas.
26. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 25, wherein the synthesis gas is used to produce hydrocarbons.
27. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 25, wherein the synthesis gas is used to produce alcohols.
28. An organic fuel synthesis plant, as claimed in Claim 1 and Claim 2 and Claim 25, and Claim 26 or Claim 27, wherein heat recovered from energy releasing reactions is transferred to the water prior to electrolysis.
29. An organic synthesis plant, incorporating some or all of the processes and technologies described in Claim I to Claim 29, wherein the organic materials produced are Llscd for industrial processes.
30. An organic synthesis plant, as claimed in Claim 1 and Claim 29, wherein the materials produced are used for the fabrication of plastics and similar materials.
31. An organic synthesis plant, as claimed in Claim 1 and Claim 29, wherein the materials produced are used for the fabrication of fibre-reinforced composites.
32. An organic synthesis plant, as claimed in Claim I and Claim 29, wherein the materials produced are used for the fabrication of pharmaceutical products.