Fuel Cell Apparatus

Abstract

A fuel cell apparatus comprises a cell stack, a reforming portion (reforming catalyst), a vaporizing portion, a reforming target gas supply, an oxygen-containing gas supply, a water supply, and a controller. The cell stack comprises a plurality of fuel cells electrically connected in series in a housing case. The reforming portion is disposed over the cell stack and is to be exposed to a gas produced by burning a fuel gas from the fuel cells. The reforming catalyst can perform partial oxidation reforming, autothermal reforming and steam reforming as a reforming reaction. The vaporizing portion generates steam to be supplied to the reforming portion. The reforming target gas supply supplies a reforming target gas to the reforming portion. The oxygen gas supply supplies an oxygen gas to the reforming portion. The water supply supplies water to the vaporizing portion. The controller controls the reforming reaction in the reforming portion.

1 . A fuel cell apparatus comprising:
 a cell stack comprising a plurality of fuel cells electrically connected in series in a housing case;   a reforming portion disposed over the cell stack and being to be exposed to a gas produced by burning a fuel gas from the fuel cells and comprising a reforming catalyst, the reforming catalyst can perform partial oxidation reforming, autothermal reforming and steam reforming as a reforming reaction;   a vaporizing portion generating steam to be supplied to the reforming portion;   a supplying portion comprising:
 a reforming target gas supply portion supplying a reforming target gas to the reforming portion; 
 an oxygen-containing gas supply portion supplying an oxygen-containing gas to the reforming portion; 
 a water supply portion supplying water to the vaporizing portion; and a controller controlling the reforming reaction in the reforming portion, 
   wherein, where T 1  represents a temperature at which the steam reforming can be performed and T 2  represents a temperature at which a predetermined amount of steam can be generated by the steam reforming, when the temperature of the reforming portion at the starting time of the fuel cell apparatus is lower than T 1 , the controller controls the supplying portion to perform a first control by which the reforming reaction is performed in the order of the partial oxidation reforming, the autothermal reforming and the steam reforming,   when the reforming portion has T 1  and the temperature of the vaporizing portion is lower than T 2 , at the starting time of the fuel cell apparatus, the controller controls the supplying portion to perform a second control by which the reforming reaction is performed in the order of the autothermal reforming and the steam reforming, and   when the reforming portion has T 1  and the vaporizing portion has T 2 , at the starting time of the fuel cell apparatus, the controller controls the supplying portion to perform a third control by which the reforming reaction is performed by the steam reforming.   
     
     
         2 . The fuel cell apparatus according to  claim 1 , wherein the reforming target gas supply portion and the oxygen-containing gas supply portion are controlled so that the amount of reforming target gas supply for the autothermal reforming is the same between the first control and the second control, and so that the ratio of the amount of oxygen-containing gas supply to the reforming portion to the amount of reforming target gas supply to the reforming portion for the autothermal reforming by the second control is smaller than that for the autothermal reforming by the first control. 
     
     
         3 . The fuel cell apparatus according to  claim 1 , wherein the controller controls the water supply portion so that the amount of steam supply to the reforming portion for the autothermal reforming by the second control is larger than that for the autothermal reforming by the first control, and so that the amount of steam supply to the reforming portion for the steam reforming by the third control is larger than that for steam reforming by the first control. 
     
     
         4 . The fuel cell apparatus according to  claim 1 , wherein the controller controls the reforming target gas supply portion so that the amount of reforming target gas supply to the reforming portion for the autothermal reforming by the second control is smaller than that for the autothermal reforming by the first control, and so that the amount of reforming target gas supply to the reforming portion for the steam reforming by the third control is smaller than that for the steam reforming by the first control. 
     
     
         5 . The fuel cell apparatus according to  claim 1 , further comprising a fuel cell-designating oxygen-containing gas supply portion supplying the oxygen-containing gas to the fuel cells, wherein the controller controls the fuel cell-designating oxygen-containing gas supply portion so that the amount of oxygen-containing gas supply to the fuel cells for the autothermal reforming by the second control is larger than that for the autothermal reforming by the first control, and so that the amount of oxygen-containing gas supply to the fuel cells for the steam reforming by the third control is larger than that for the steam reforming by the first control. 
     
     
         6 . A method for controlling a reforming reaction with a fuel cell apparatus, comprising:
 measuring a temperature of a reforming portion in the fuel cell apparatus at the starting time of the fuel cell apparatus;   measuring a temperature of a vaporizing portion in the fuel cell apparatus at the starting time of the fuel cell apparatus;   performing a first reforming reaction in which partial oxidation reforming, autothermal reforming and steam reforming are performed in that order as the reforming reaction when the temperature of the reforming portion is lower than T 1 , where T 1  represents a temperature at which the steam reforming can be performed;   performing a second reforming reaction in which autothermal reforming and steam reforming are performed in that order as the reforming reaction when the reforming portion has T 1  and the temperature of the vaporizing portion is lower than T 2 , where T 2  represents a temperature at which a predetermined amount of steam can be generated by the steam reforming; and   performing a third reforming reaction in which steam reforming is performed as the reforming reaction when the reforming portion has T 1  and the vaporizing portion has T 2 .   
     
     
         7 . The method for performing a reforming reaction with a fuel cell apparatus according to  claim 6 , further comprising:
 supplying reforming target gas so that the amount of reforming target gas supply for the autothermal reforming is the same between the first reforming reaction and the second reforming reaction; and   supplying oxygen-containing gas so that the ratio of the amount of oxygen-containing gas supply to the reforming portion to the amount of reforming target gas supply to the reforming portion for the autothermal reforming by the second reforming reaction is smaller than that for the autothermal reforming by the first reforming reaction.   
     
     
         8 . The method for performing a reforming reaction with a fuel cell apparatus according to  claim 6 , further comprising:
 supplying steam so that the amount of steam supply to the reforming portion for the autothermal reforming by the second reforming reaction is larger than that for the autothermal reforming by the first reforming reaction, and so that the amount of steam supply to the reforming portion for the steam reforming by the third reforming reaction is larger than that for steam reforming by the first reforming reaction.   
     
     
         9 . The method for performing a reforming reaction with a fuel cell apparatus according to  claim 6 , further comprising:
 supplying reforming target gas so that the amount of reforming target gas supply to the reforming portion for the autothermal reforming by the second reforming reaction is smaller than that for the autothermal reforming by the first reforming reaction, and so that the amount of reforming target gas supply to the reforming portion for the steam reforming by the third reforming reaction is smaller than that for the steam reforming by the first reforming reaction.   
     
     
         10 . The method for performing a reforming reaction with a fuel cell apparatus according to  claim 6 , further comprising:
 supplying oxygen-containing gas so that the amount of oxygen-containing gas supply to fuel cells in the fuel cell apparatus for the autothermal reforming by the second reforming reaction is larger than that for the autothermal reforming by the first reforming reaction, and so that the amount of oxygen-containing gas supply to the fuel cells for the steam reforming by the third reforming reaction is larger than that for the steam reforming by the first reforming reaction.