Cascading pressure reactor and method for solar-thermochemical reactions
View Patent ↗Reactors and methods for solar thermochemical reactions are disclosed. The reactors and methods include a cascade of reduction chambers at successively lower pressures that leads to over an order of magnitude pressure decrease compared to a single-chambered design. The resulting efficiency gains are substantial, and represent an important step toward practical and efficient solar fuel production on a large scale.
1. A solar thermochemical reactor comprising:
a thermal reduction zone to thermally reduce a plurality of reactive particles through direct heating by solar energy thereby producing a plurality of reduced particles;
wherein the thermal reduction zone comprises two or more thermal reduction sub-zones operating at a corresponding two or more decreasing pressures;
wherein the two or more thermal reduction sub-zones receive separate solar inputs; and
wherein the pressure decreases in the direction of particle flow.
2. The solar thermochemical reactor of claim 1 , wherein the thermal reduction zone is heated by solar input.
3. The solar thermochemical reactor of claim 1 , wherein the two or more thermal reduction sub-zones are two or more reduction reactors.
4. The solar thermochemical reactor of claim 1 , wherein the particles are first reduced in a first reduction reactor of the two or more reduction reactors, and the first reduction reactor is at a pressure of between 10 Pa and 1000 Pa.
5. The solar thermochemical reactor of claim 1 , wherein the two or more thermal reduction sub-zones operate at a temperature greater than 1200° C.
6. The solar thermochemical reactor of claim 1 , further comprising:
a heating zone configured to heat the plurality of reactive particles through direct heating by solar energy to a temperature less than the plurality of reactive particles nominal reduction temperature.
7. The solar thermochemical reactor of claim 1 , wherein reduction of the plurality of reactive particles in the thermal reduction zone produces a reduction product stream.
8. The solar thermochemical reactor of claim 6 , wherein the reduction product stream comprises oxygen.
9. The solar thermochemical reactor of claim 1 , further comprising:
an oxidation zone for receiving the plurality of reduced particles;
wherein the plurality of reduced particles undergo oxidation in the oxidation zone thereby reducing a feedstock and forming an oxidation product.
10. The solar thermochemical reactor of claim 1 , wherein the oxidation product is hydrogen.
11. A method for reducing a redox active material, comprising:
thermally reducing a plurality of reactive particles in a thermal reduction zone through direct heating by solar energy to produce a plurality of reduced particles;
wherein the thermal reduction zone comprises two or more thermal reduction sub-zones operating at a corresponding two or more decreasing pressures;
wherein the solar energy directly heats by separate solar inputs to the two or more thermal reduction sub-zones; and
wherein the pressure decreases in the direction of particle flow.
12. The method of claim 10 , wherein the thermal reduction zone is heated by solar input.
13. The method of claim 10 , wherein the two or more thermal reduction sub-zones are two or more reduction reactors.
14. The method of claim 10 , wherein the particles are first reduced in a first reduction reactor of the two or more reduction reactors, and the first reduction reactor is at a pressure of between 10 Pa and 1000 Pa.
15. The method of claim 10 , wherein the two or more thermal reduction sub-zones operate at a temperature greater than 1200° C.
16. The method of claim 10 , further comprising:
heating zone the plurality of reactive particles in a heating zone through direct heating by solar energy to a temperature less than the plurality of reactive particles nominal reduction temperature.
17. The method of claim 10 , wherein reduction of the plurality of reactive particles in the thermal reduction zone produces a reduction product stream.
18. The method of claim 16 , wherein the reduction product stream comprises oxygen.
19. The method of claim 10 , further comprising:
oxidizing the plurality of reduced particles in an oxidation zone;
wherein oxidation in the oxidation zone reduces a feedstock and forms an oxidation product.
20. The method of claim 10 , wherein the oxidation product is hydrogen.