Fuel Cell with Low Water Consumption

Abstract

A technique to provide fuel to a solid oxide fuel cell with low water consumption is described that includes providing an initial fuel mixture with air and hydrocarbon, and partially oxidizing the fuel mixture with a catalyst to provide a reformed fuel mixture. Also included is adding an amount of water to the reformed fuel mixture to reduce formation of elemental carbon from carbon monoxide in the reformed fuel mixture and supplying a portion of the reformed fuel mixture combined with water to an electrochemical device that produces electrical power from hydrogen in the reformed fuel mixture.

1 - 16 . (canceled) 
     
     
         17 . An apparatus comprising:
 a mixer that receives an air stream and a fuel stream, and produces a mixed fuel stream;   a reformer having a partial oxidation catalyst that reacts the mixed fuel stream to produce a hydrogen-enriched stream;   a suppression device that adds an effective amount of water to the hydrogen-enriched stream to produce a combined stream, wherein the effective amount of water comprises an amount of water sufficient to reduce a rate of a reaction to form carbon from carbon monoxide in the combined stream; and   a solid oxide fuel cell that generates electricity from the combined stream.   
     
     
         18 . The apparatus according to claim  16  wherein the suppression device comprises a steam supply and a steam valve configured to control a steam addition rate to the hydrogen-enriched stream. 
     
     
         19 . The apparatus according to claim  16  further comprising means for maintaining the hydrogen-enriched stream at a temperature below about 600 degrees C. 
     
     
         20 . The apparatus according to claim  16  further comprising means for providing the effective amount of water so that the rate of the reaction:
   CO+H 2 →C+H 2 O
 
 
       is reduced by a factor of at least 2. 
     
     
         21 . The apparatus according to claim  16  further comprising means for providing the effective amount of water so that the combined stream comprises a specified water concentration. 
     
     
         22 . The apparatus according to claim  16 , further comprising an ambient humidity module configured to interpret an ambient air water content, and further comprising means for providing the effective amount of water so that the combined stream comprises a specified water concentration based on the ambient water content. 
     
     
         23 . A system comprising:
 a mixer that receives an air stream and a fuel stream, and provides an initial fuel mixture;   a reformer having a partial oxidation catalyst that reacts the initial fuel mixture to produce a hydrogen-enriched stream;   a suppression device that adds an effective amount of water to the hydrogen-enriched stream to produce a combined stream, wherein the effective amount of water comprises an amount of water sufficient to reduce a rate of a reaction to form carbon from carbon monoxide in the combined stream;   a solid oxide fuel cell that generates electricity from the combined stream; and a vehicle carrying the mixer, reformer, suppression device, and solid oxide fuel cell, the vehicle including a drive train at least partially powered by the electricity from the solid oxide fuel cell.   
     
     
         24 . A system according to  claim 23 , further comprising a water supply tank that supplies water to the suppression device. 
     
     
         25 . A system according to  claim 23 , wherein the suppression device further comprises a steam generator that vaporizes the water from the water supply tank.