Ignition method of fuel reformer using partial oxidation reaction of the fuel for SOFC fuel cell start-up
In accordance with one or more embodiments of the present disclosure, a method of starting a fuel reformer including a heating element and a subsequent autothermal reformer includes contacting a first fluid comprising oxygen with the heating element, passing the first fluid into the autothermal reformer to preheat a reformer catalyst within the autothermal reformer to a first temperature, reducing flow of the first fluid into the autothermal reformer, introducing a fuel into the autothermal reformer subsequent to preheating the reformer catalyst to initiate a partial oxidation reaction and generating additional heat, increasing flow of the fuel and first fluid to initiate autothermal reforming, and controlling the temperature of the reformer catalyst by supplying a cooling fluid, the first fluid, and the fuel and adjusting flow of each.
1. A method of starting a fuel reformer, the fuel reformer including a heating element and an autothermal reformer disposed at a rear end of the heating element, the method comprising in this order of steps:
I. contacting a first fluid comprising oxygen with the heating element;
II. passing the first fluid into the autothermal reformer to preheat a reformer catalyst contained within the autothermal reformer to a first temperature;
III. reducing flow of the first fluid into the autothermal reformer;
IV. introducing a fuel into the autothermal reformer subsequent to preheating the reformer catalyst to initiate a partial oxidation reaction within the autothermal reformer to generate additional heat;
V. increasing flow of the fuel and the first fluid to initiate autothermal reforming; and
VI. controlling the temperature of the reformer catalyst by supplying a cooling fluid, the first fluid, and the fuel to the autothermal reformer and adjusting flow of each of the cooling fluid, the first fluid, and the fuel.
2. The method of claim 1 , wherein the first fluid is air.
3. The method of claim 1 , wherein the fuel is diesel.
4. The method of claim 1 , wherein the cooling fluid comprises water.
5. The method of claim 1 , wherein step V comprises increasing flow of the fuel and the first fluid in a stepwise manner.
6. The method of claim 1 , wherein step V comprises initiating the increase of the flow of the fuel prior to initiating the increase in the flow of the first fluid.
7. The method of claim 1 , wherein step V is initiated upon verification of initiation of the partial oxidation reaction within the autothermal reformer.
8. The method of claim 1 , wherein the fuel reformer further includes a nozzle disposed at a front end of the heating element, the nozzle configured to supply the first fluid and the fuel to the fuel reformer.
9. The method of claim 8 , wherein the nozzle is a two-fluid nozzle.
10. The method of claim 1 , wherein the autothermal reformer comprises a monolithic catalyst.
11. The method of claim 10 , wherein the monolithic catalyst comprises nickel.
12. The method of claim 1 , further comprising terminating operation of the heating element after the reformer catalyst reaches a second temperature, wherein the second temperature is greater than the first temperature.
13. The method of claim 12 , wherein the cooling fluid comprises water and wherein the water is heated to the second temperature exterior to the autothermal reformer prior to the supplying the cooling fluid to the autothermal reformer.
14. The method of claim 12 , wherein the first temperature is 200° C. to 300° C. and the second temperature is 450° C. to 550° C.
15. The method of claim 1 , wherein the first fluid in steps I and II is recirculated from an outlet of the fuel reformer to an inlet of the fuel reformer.
16. A method of starting a diesel fuel reformer, the diesel fuel reformer including a heating element and an autothermal reformer disposed at a rear end of the heating element, the method comprising in this order of steps:
I. contacting air with the heating element;
II. passing the air into the autothermal reformer to preheat a reformer catalyst contained within the autothermal reformer to a first temperature;
III. reducing flow of the air into the autothermal reformer;
IV. introducing diesel into the autothermal reformer subsequent to preheating the reformer catalyst to initiate a partial oxidation reaction within the autothermal reformer to generate additional heat;
V. increasing flow of the diesel and the air to initiate autothermal reforming; and
VI. controlling the temperature of the reformer catalyst by supplying a cooling fluid comprising water, the air, and the diesel to the autothermal reformer and adjusting flow of each of the cooling fluid, the air, and the diesel.
17. The method of claim 16 , wherein step V comprises increasing flow of the diesel and the air in a stepwise manner.
18. The method of claim 16 , wherein step V comprises initiating the increase of the flow of the diesel prior to initiating the increase in the flow of the air.
19. The method of claim 16 , wherein step V is initiated upon verification of initiation of the partial oxidation reaction within the autothermal reformer.
20. The method of claim 16 , further comprising terminating operation of the heating element after the reformer catalyst reaches a second temperature, wherein the second temperature is greater than the first temperature.
21. The method of claim 20 , wherein the first temperature is 200° C. to 300° C. and the second temperature is 450° C. to 550° C.
22. The method of claim 16 , wherein the air in step I is recirculated from an outlet of the diesel fuel reformer to an inlet of the diesel fuel reformer.