Apparatus for enclosing a chemical looping process
The present invention relates generally to an apparatus for housing a chemical looping process comprising of at least one fluidized-bed combustor reactor, at least one entrained riser, at least one particle separator, optionally at least one particle holding reactor, at least one moving-bed reactor, at least one standpipe, at least one L-valve system for solid flow control and interconnecting sections.
1. A chemical looping system comprising:
a fluidized-bed combustor reactor comprising a windbox, a heat exchange surface, and an oxidant distribution grid;
a particle;
a particle separator;
a riser;
a particle receiver; and
a moving-bed reactor;
wherein the fluidized-bed combustor reactor oxidizes the particle, creates a carrier gas, and the riser transports the oxidized particle and the carrier gas to the particle separator; and
wherein the particle receiver receives the oxidized particle from the particle separator and the moving-bed reduces the oxidized particle in the presence of a carbon-based fuel; and
wherein the riser and the moving-bed reactor share a common wall.
2. The chemical looping system of claim 1 , further comprising:
a oxidizer reactor, wherein the reduced particle is partially oxidized in the presence of a steam stream upstream of the fluidized-bed combustor reactor to produce a hydrogen stream and the partially oxidized particle is transported to the fluidized-bed combustor reactor.
3. The chemical looping system of claim 1 , further comprising:
a standpipe, and
a L-valve, wherein the standpipe and the L-valve transport the reduced particle from the moving-bed reactor to the fluidized-bed combustor reactor and the fluidized-bed combustor reactor reoxidizes the reduced particle.
4. The chemical looping system of claim 1 , wherein the common wall is a membrane wall.
5. The chemical looping system of claim 4 , wherein the membrane wall is insulated.
6. The chemical looping system of claim 3 , wherein the distribution grid is a bubble cap-type distributor capable of supplying a oxidant, a fuel, or a oxidant/fuel mixture.
7. The chemical looping system of claim 3 , wherein the heat exchanger surface is a serpentine in-bed heat exchange surface formed from serpentine in-bed heat exchanger tubes.
8. The chemical looping system of claim 7 , wherein a leading edge of the serpentine in-bed heat exchanger tubes are set back from the L-valve.
9. The chemical looping system of claim 3 , wherein the carbon-based fuel is selected from one or more of coal, oil, oil shale, oil sands, biomass, methane-rich gases, flare gases, fuel-rich waste gases from fuel cells, or mixtures of two or more thereof.
10. The chemical looping system of claim 3 , wherein the riser is rectangular in shape.
11. The chemical looping system of claim 3 , wherein the particle receiver comprises an expanded section whereby the velocity of the carrier gas for the oxidized particle is reduced and the oxidized particle drops out of suspension.
12. The chemical looping system of claim 11 , wherein the particle separator further comprises an outlet port for the carrier gas and an eroded oxidized particle.
13. The chemical looping system of claim 3 , wherein at least one wall of the particle separator is a membrane wall and the membrane wall removes thermal energy from the system.
14. The chemical looping system of claim 3 , wherein the carbon-based fuel is introduced at the bottom of the moving-bed reactor and the moving-bed reactor operates with counter current flow.
15. The chemical system of claim 3 , wherein the carbon-based fuel is introduced at the middle of the moving-bed reactor.
16. The chemical looping system of claim 3 , wherein the moving-bed reactor comprises one or more feed ports and the ports introduce a gaseous stream to a bottom portion of the moving-bed reactor.
17. The chemical looping system of claim 3 , wherein the moving-bed reactor is a reformer reactor and a fuel is introduced to the top of the moving-bed reactor, and the moving-bed reactor operates with co-current flow.
18. The chemical looping system of claim 3 , wherein the moving-bed reactor comprises one or more feed ports and the ports introduce a gaseous stream to a top portion of the moving-bed reactor.
19. The chemical looping system of claim 3 , wherein the standpipe contains a moving bed of solids that inhibits mixing of gases between the fluidized-bed combustor reactor and the moving-bed reactor.
20. The chemical looping system of claim 3 , wherein the L-valve controls a flow of solids to the moving-bed reactor.
21. The chemical looping system of claim 3 , wherein the particle is between about 25 micrometers to about 2.5 millimeters wide.
22. The chemical looping system of claim 3 , wherein the system is operated under pressure.
23. The chemical looping system of claim 3 , wherein the system is operated with one or more parallel elements.
24. The chemical looping system of claim 4 , wherein one of water, steam, carbon dioxide, or air flows through the membrane wall.
25. The chemical looping system of claim 1 , wherein the common wall is also shared with the particle separator.
26. The chemical looping system of claim 3 , wherein a CO 2 stream is introduced into the system as an enhancer gas.
27. The chemical looping system of claim 3 , wherein the moving-bed reactor further comprises an outlet gas port at an elevation above that at which the oxidized particle enters the moving-bed reactor.
28. The chemical looping system of claim 10 , wherein the riser further comprises a discharge dipleg.