Solar receiver-reactor

Patent metadata

Field	Value
Publication number	US-12240756-B2
Application number	US-201917051693-A
Country	US
Kind code	B2
Filing date	May 3, 2019
Priority date	May 7, 2018
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

The invention relates to a method for producing syngas by means of solar radiation, in which the reactor of a receiver-reactor is periodically heated via an aperture provided in the same for solar radiation by means of the solar radiation to an upper reduction temperature for a reduction process and subsequently cooled to a lower oxidation temperature for an oxidation process in the presence of an oxidation gas, wherein the sunlight is guided through an absorption chamber onto an absorber configured as a reactor, which includes a reducible/oxidizable material, and wherein a gas that absorbs the black-body radiation of the absorber is guided through the absorption chamber and the absorption chamber is configured so that the back radiation of the absorber through the aperture is essentially absorbed by the gas. Radiation losses caused by back radiation of the black-body radiation exiting the optical aperture are thus avoided in accordance with the invention. The heat of the back radiation, however, can be utilized directly in the heat-transporting fluid and is available for a flexible usage. The receiver-reactor has a simple design and is suitable as a low-cost receiver-reactor.

First claim

The invention claimed is:

1. A method for producing syngas by using solar radiation, in which a reactor of a receiver-reactor is periodically heated via an aperture provided therein for solar radiation using the solar radiation to an upper reduction temperature (T O ) for a reduction process and subsequently cooled to a lower oxidation temperature (T U ) for an oxidation process in the presence of an oxidation gas, comprising:
guiding sunlight through an absorption chamber onto an absorber configured as the reactor, which includes a reducible/oxidizable material; and
guiding a gas that absorbs black-body radiation of the absorber through the absorption chamber, wherein an absorption area is configured so that 80% or more of the black-body radiation of the absorber present on a path to the aperture is absorbed.

2. The method for producing syngas using solar radiation according to claim 1 , wherein 85% or more of the black-body radiation of the absorber travelling on the path to the aperture is absorbed.

3. The method according to claim 1 , wherein an at least oxidizing gas is used as an infrared-absorbing gas, said gas being guided through the absorption chamber to the absorber in such a manner that it participates in the redox reaction in the absorption chamber and is reduced by the absorber in the oxidation phase.

4. The method according to claim 3 , wherein the at least oxidizing gas is guided into a separation station downstream from the absorber and syngas is separated from the at least oxidizing gas in the separation station, wherein the oxidizing gas is further guided in the circuit back to the absorption chamber and is cooled in this circuit in a heat exchanger before the absorber in the direction of flow.

5. The method according to claim 3 , wherein the at least oxidizing gas is guided during the reduction process and/or during the oxidation process of the absorber through the same in a such a manner that said gas is heated convectively.

6. The method according to claim 1 , wherein a gas whose partial pressure of oxygen at a temperature prevailing during the reduction phase of the reactor is equal to or less than the higher value of the partial pressure of oxygen of water vapour or CO 2 at this temperature is used as an infrared-absorbing gas, and wherein this gas is guided at least during the reduction phase through the absorption chamber to the absorber in such a manner that the latter is reduced in the presence of this gas.

7. The method according to claim 1 , wherein the absorbing gas is removed as a heat-transporting fluid from the receiver-reactor after absorbing the black-body radiation of the absorber without participating in the redox reaction, and wherein an at least oxidizing gas is fed to the absorber for the redox reaction separately from the absorbing gas.

8. The method according to claim 7 , wherein the at least oxidizing gas is fed to a side of the absorber facing away from the absorption area.

9. The method according to claim 7 , wherein the at least oxidizing gas is guided through the absorber, wherein the absorber is configured as a tube bundle for the oxidizing gas.

10. The method according to claim 1 , wherein a heteropolar gas selected from the group consisting of CO 2 , water vapour, CH 4 , NH 3 , CO, SO 2 , SO 3 , HCI, NO and NO 2 or a mixture thereof is used as an infrared-absorbing gas.

11. The method according to claim 1 , wherein gas heated by absorption of the black-body radiation of the absorber is removed from the absorption area as soon as it is partially heated and/or a partially heated gas is fed to the absorption area, and wherein the feeding into the absorption area takes place at the respective site where the temperature in the absorption area essentially corresponds to the temperature of the partially heated gas.

12. The method according to claim 1 , wherein cerium dioxide (CeO 2 ), doped CeO 2 or perovskite are used as reducible/oxidizable material.

13. A solar reactor-receiver comprising:
an optical aperture for radiation of the sun;
an absorber arranged in a path of incident light;
a redox reactor for a redox reaction;
a transport arrangement in which an oxidizing gas is guided in a serviceable state to and away from the reactor, wherein the absorber is configured as the redox reactor; and
an absorption chamber is arranged between the aperture for the radiation of the sun and the absorber in the path of the incident light and in the path of black-body radiation of the absorber, wherein the transport arrangement includes a circuit line arrangement, in which a heat-transporting fluid circulates, wherein the circuit is configured in such a manner that the heat-transporting fluid can be charged with heat in an absorption area and cooled again in the heat exchanger, wherein the heat-transporting fluid is an infrared-absorbing gas that absorbs black-body radiation of the absorber travelling on a path through the aperture.

14. The solar reactor-receiver according to claim 13 , wherein the heat-transporting fluid is composed and the transport arrangement and the absorption area are configured in such a manner that, during the operation of the reactor, the heat-transporting fluid absorbs≥80% of the black-body radiation of the absorber present on a path through the aperture for the radiation of the sun.

15. The solar reactor-receiver according to claim 13 , wherein the heat-transporting fluid is a gas that is reducible during the oxidation of the absorber and wherein the reducible/oxidizable material of the absorber is arranged on the same in such a manner that it lies in a serviceable state in the flow path of the heat-transporting fluid so that the fluid is reduced in the oxidation phase of the redox reactor.

16. The solar reactor-receiver according to claim 13 , wherein the heat-transporting fluid is an infrared-absorbing gas with a partial pressure of oxygen which, at a temperature prevailing during the reduction phase of the redox reactor, is equal to or not as high as the higher value of the partial pressure of oxygen of water vapour or CO 2 at this temperature, and wherein the circuit line arrangement is configured to guide this gas at least during the reduction phase through the absorption chamber to the absorber in such a manner that the absorber is reduced during operation during its reduction phase in the presence of this gas.

17. The solar reactor-receiver according to claim 13 , wherein the circuit line arrangement further includes a separation station configured to separate syngas from the heat-transporting fluid and make it available for removal from the circuit.

18. The solar reactor-receiver according to claim 13 , wherein the reducible/oxidizable material is arranged on the surface of the absorber facing the absorption chamber and the absorber is configured so as to be plate-shaped.

19. The solar reactor-receiver according to claim 13 , wherein the absorber is configured in such a manner that heat-transporting fluid can flow through it and the surface of the area of flow consists at least partially of reducible/oxidizable material.

20. The solar reactor-receiver according to claim 13 , wherein the receiver-reactor further includes a line arrangement for at least oxidizing gas that guides said gas separately from the absorbing gas.

21. The solar reactor-receiver according to claim 20 , wherein the absorber is linked to the circuit line arrangement and the further line arrangement for oxidizing gas and forms a partition between the flow path of the h

Assignees

• Synhelion Sa
• Eni Spa

Inventors

• Ambrosetti Gianluca
• Good Philipp

Classifications

• B01J2219/1203

  Incoherent waves · CPC title

• B01J2219/0886

  Gas-solid · CPC title

• B01J2219/0871

  Heating or cooling of the reactor · CPC title

• B01J19/127

  Sunlight; Visible light · CPC title

• B01J15/00

  Chemical processes in general for reacting gaseous media with non-particulate solids, e.g. sheet material; Apparatus specially adapted therefor (B01J19/08 takes precedence) · CPC title