Maintaining oxygen/carbon ratio with temperature controlled valve

Abstract

Fuel from a source ( 6 ) passes through a hydrogen desulfurizer ( 8 ) and a proportioning mixing valve ( 10 ) to a CPO ( 31 ), the temperature of the output of the CPO being monitored ( 50 ) to provide a signal ( 51 ) which a controller ( 52 ) utilizes to adjust the valve ( 10 ). The output of the CPO may be passed through a water gas shift reactor ( 35 ) and a preferential CO oxidizer ( 40 ) to provide fuel to a fuel cell system ( 26 ). The air provided to the valve ( 10 ) may be humidified, such as by an enthalpy recovery device ( 21 ) receiving the oxidant outflow ( 24 ) from the fuel cell system.

1 . A catalytic partial oxidizer system comprising: 
 a catalytic partial oxidizer having an inlet and an outlet;    a fuel supply;    a source of air;    a proportioning mixing valve having two inlets and an outlet and controllable so as to determine the proportion of gases at the respective inlets which will be provided to the outlet, one inlet being connected to said fuel supply and the other inlet being connected to said source of air, the outlet of said valve being connected to the inlet of said CPO;    a temperature sensor for providing a signal indicative of the temperature of flow at the outlet of said CPO; and    a controller responsive to said signal to control said valve and thereby control the proportions of gas at the respective inlets which are provided through said valve to said CPO.    
   
   
       2 . A system according to  claim 1  wherein: 
 said controller processes said signal with proportional and integral gain.    
   
   
       3 . A system according to  claim 1  wherein: 
 the outflow of said CPO is provided to a fuel cell system having a cathode exhaust passing through an enthalpy recovery device which comprises said source of air.    
   
   
       4 . A system according to  claim 1  wherein: 
 said source of air is a source of humidified air.    
   
   
       5 . A system according to  claim 1  wherein: 
 said fuel supply provides fuel selected from natural gas and liquified petroleum gas.    
   
   
       6 . A system according to  claim 1  wherein: 
 said fuel supply includes a hydrodesulfurizer.