Method and system for reducing pollutant emissions of a power system

Abstract

A method for reducing pollutant emissions of a power system may include the steps of providing a first portion of an ethanol additive to a first power source, wherein the first power source includes a combustion chamber. The method may also include supplying a second portion of the ethanol additive to a second power source and providing a primary fuel to the combustion chamber. The method may further include the steps of combusting at least a portion of primary fuel and at least some of the first portion of ethanol additive in the combustion chamber, wherein the combustion results in formation of an exhaust-gas stream, providing a third portion of ethanol additive to the exhaust-gas stream, and exposing the exhaust-gas stream to a selective catalytic reduction system catalyst.

1 . A method for reducing pollutant emissions of a power system, the method comprising: 
 providing a first portion of an ethanol additive to a first power source, wherein the first power source includes a combustion chamber;    supplying a second portion of the ethanol additive to a second power source;    providing a primary fuel to the combustion chamber;    combusting at least a portion of primary fuel and at least some of the first portion of ethanol additive in the combustion chamber, wherein the combustion results in formation of an exhaust-gas stream;    providing a third portion of ethanol additive to the exhaust-gas stream; and    exposing the exhaust-gas stream to a selective catalytic reduction system catalyst.    
   
   
       2 . The method of  claim 1 , wherein the second power source includes a fuel cell.  
   
   
       3 . The method of  claim 2 , wherein the second power source further includes a fuel processor.  
   
   
       4 . The method of  claim 3 , further including: 
 processing at least a portion of the second portion of the ethanol additive to generate at least one of hydrogen, carbon dioxide, or water; and    providing hydrogen to the fuel cell.    
   
   
       5 . The method of  claim 1 , wherein the ethanol additive includes hydrous ethanol.  
   
   
       6 . The method of  claim 5 , wherein the hydrous ethanol includes water in an amount between about 30 percent by volume and about 80 percent by volume.  
   
   
       7 . The method of  claim 1 , wherein the selective reduction catalyst system catalyst includes a lean-NOx catalyst.  
   
   
       8 . The method of  claim 1 , further including: 
 determining a quantity of ethanol additive in the exhaust-gas stream; and    controlling a volume of the third portion of the ethanol additive based on the determination.    
   
   
       9 . The method of  claim 1 , further including: 
 receiving a request for power;    determining a first operational state associated with the first power source and a second operational state associated with the second power source; and    controlling, based on the request and the determination of the first and second operational states, a volume of at least one of the first portion, second portion, or third portion of the ethanol additive.    
   
   
       10 . The method of  claim 9 , wherein determining the first operational state includes identifying a first existing power load on the first power source and determining the second operational state includes identifying a second existing power load on the second power source.  
   
   
       11 . The method of  claim 10 , wherein determining the first operational state further includes determining whether the first power source is available for production of power and determining the second operational state includes determining whether the second power source is available for production of power.  
   
   
       12 . The method of  claim 11 , wherein controlling a volume of at least one of the first portion, second portion, or third portion of the ethanol additive further includes: 
 if the first power source is available for production of power and the first existing power load does not exceed a predetermined threshold, supplying the first portion of ethanol additive to the first power source; and    if the second power source is available for production of power and the second existing power load does not exceed a predetermined threshold, supplying the second portion of ethanol additive to the second power source.    
   
   
       13 . The method of  claim 3 , further including: 
 extracting heat from the first power source; and    providing the heat to the fuel processor.    
   
   
       14 . A system for reducing emissions, the system comprising: 
 a first power source, including a combustion chamber and an exhaust system;    a second power source configured to receive an ethanol additive; and    a controller operatively connected to the first power source and the second power source, wherein the controller is configured to: 
 receive a request for power;  
 determine a first operational state associated with the first power source and a second operational state associated with the second power source; and  
 based on the request and the determination of the first and second states, cause an ethanol additive to be provided to at least one of the first power source, the second power source, or the exhaust system.  
   
   
   
       15 . The system of  claim 14 , wherein the second power source includes a fuel cell.  
   
   
       16 . The system of  claim 14 , further including a fuel processor fluidly connected to the fuel cell.  
   
   
       17 . The system of  claim 16 , wherein the fuel processor is configured to process at least a portion of ethanol additive to yield at least a fuel for the fuel cell.  
   
   
       18 . The system of  claim 14 , wherein the second power source is configured to provide power to at least one of the traction device and the at least one auxiliary device.  
   
   
       19 . The system of  claim 14 , further including a heat exchanger configured to remove heat from the first power source and provide at least a portion of the removed heat to the second power source.  
   
   
       20 . The system of  claim 14 , wherein determining the first operational state includes identifying a first existing power load on the first power source and determining the second operational state includes identifying a second existing power load on the second power source.  
   
   
       21 . The system of  claim 20 , wherein determining the first operational state further includes determining whether the first power source is available for production of power and determining the second operational state includes determining whether the second power source is available for production of power.  
   
   
       22 . The system of  claim 21 , wherein the ethanol additive is provided to the first power source if the first power source is available for production of power and the first existing power load does not exceed a predetermined threshold, and the ethanol additive is provided to the second power source if the second power source is available for production of power and the second existing power load does not exceed a predetermined threshold.  
   
   
       23 . A machine, comprising: 
 a frame;    a traction device;    a first power source operatively connected to the frame and the traction device, wherein the first power source includes: 
 at least one combustion chamber;  
 an exhaust system fluidly connected to the at least one combustion chamber and configured to receive an exhaust-gas stream;  
 a fuel source configured to supply a primary fuel to the at least one combustion chamber;  
 an additive supply device configured to supply a first portion of an ethanol additive to the at least one combustion chamber;  
 a secondary additive supply device configured to supply a second portion of the ethanol additive to the exhaust system; and  
 a selective reduction catalyst system catalyst fluidly connected to the exhaust system and configured to receive the exhaust gas stream; and  
   a second power source configured to receive a third portion of the ethanol additive.    
   
   
       24 . The machine of  claim 23 , wherein the second power source includes a fuel cell.  
   
   
       25 . The machine of  claim 23 , further including a fuel processor.  
   
   
       26 . The machine of  claim 23 , wherein the second power source provides power to at least one of the traction device and at least one auxiliary device.  
   
   
       27 . The machine of  claim 23 , further including a heat exchanger configured to remove energy from the first power source and provide at least a portion of the removed energy to the second power source.