Dual stage internal combustion engine aftertreatment system using common radiator cooling fluid circuits for exhaust gas intercooling and charger-driven ejector

Abstract

An engine radiator cooling fluid circuit and an exhaust gas intercooler (EGI) radiator cooling fluid circuit are fluidically in parallel with one another. The engine radiator cooling fluid circuit extends from the radiator to an engine associated with a vehicle or a stationary system such as a CHP system. The EGI radiator cooling fluid circuit extends from a radiator to an EGI that cools exhaust gas as it flows through an exhaust conduit that extends from a first catalytic converter to a second catalytic converter. The radiator cooling fluid circuits can share a common radiator coil or each radiator cooling fluid circuit can be associated with a respective radiator coil in the radiator. A gas particulate filter can be coupled to the exhaust conduit or the second catalytic converter. An air-driven exhaust gas ejector (EGE) such as an engine charger compressor injects air into an inlet port in the exhaust conduit.

What is claimed is: 
     
         1 . A system comprising:
 a spark-ignited internal-combustion engine;   a first catalytic converter including a three-way catalyst, the first catalytic converter receiving an exhaust generated by said engine;   an exhaust gas intercooler configured to cool a treated exhaust output of said first catalytic converter;   a radiator;   an EGI radiator cooling fluid circuit in thermal communication with said exhaust gas intercooler and said radiator;   an engine radiator cooling fluid circuit in thermal communication with said engine and said radiator, wherein said engine radiator cooling fluid circuit is fluidically in parallel with said EGI radiator cooling fluid circuit; and   a second stage catalyst for further chemical treatment of the cooled oxygen enriched exhaust gas stream.   
     
     
         2 . The system of  claim 1 , wherein said EGI radiator cooling fluid circuit and said engine radiator cooling fluid circuit share a common radiator cooling fluid path that extends through a common radiator coil in said radiator. 
     
     
         3 . The system of  claim 2 , further comprising a flow control valve disposed between (a) said common radiator cooling fluid path and (b) an EGI radiator cooling fluid path that extends through said EGI, wherein a controller adjusts an operating position of said flow control valve to adjust said flow rate of said radiator cooling fluid through said EGI radiator cooling fluid path, the EGI radiator cooling fluid path comprising a portion of said EGI radiator cooling fluid circuit. 
     
     
         4 . The system of  claim 1 , wherein said EGI radiator cooling fluid circuit passes through a first radiator coil in said radiator and said engine radiator cooling fluid circuit passes through a second radiator coil in said radiator. 
     
     
         5 . The system of  claim 1 , further comprising a controller to adjust a flow rate of radiator cooling fluid through said EGI radiator cooling fluid circuit. 
     
     
         6 . The system of  claim 5 , wherein said controller receives as an input a temperature sensed by a thermocouple disposed proximal to an outlet of the exhaust gas intercooler. 
     
     
         7 . The system of  claim 6 , wherein said controller is in electrical communication with a radiator fluid pump to adjust said flow rate. 
     
     
         8 . An exhaust aftertreatment system comprising:
 a first catalytic converter including a three-way catalyst, the first catalytic converter receiving an exhaust generated by a spark-ignited internal-combustion engine;   a second catalytic converter including an oxidation catalyst or a three-way catalyst;   an exhaust gas intercooler (EGI) disposed between said first catalytic converter and said second catalytic converter, said EGI configured to reduce a temperature of said exhaust to about 300° F. to about 500° F.;   an exhaust conduit extending from said first catalytic converter to said second catalytic converter, said exhaust conduit in thermal communication with said EGI;   an air injector in fluid communication with an inlet port in the exhaust conduit to introduce air into the exhaust conduit;   a radiator;   an EGI radiator cooling fluid circuit in thermal communication with said exhaust gas intercooler and a radiator; and   an engine radiator cooling fluid circuit in thermal communication with said engine and said at least one radiator, wherein said engine radiator cooling fluid circuit is fluidically in parallel with said EGI radiator cooling fluid circuit.   
     
     
         9 . The exhaust aftertreatment system of  claim 8 , wherein said EGI radiator cooling fluid circuit and said engine radiator cooling fluid circuit share a common radiator cooling fluid path that extends through a common radiator coil in said radiator. 
     
     
         10 . The exhaust aftertreatment system of  claim 9 , further comprising a flow control valve disposed between (a) said common radiator cooling fluid path and (b) an EGI radiator cooling fluid path that extends through said EGI, wherein a controller adjusts an operating position of said flow control valve to adjust said flow rate of said radiator cooling fluid through said EGI radiator cooling fluid path, the EGI radiator cooling fluid path comprising a portion of said EGI radiator cooling fluid circuit. 
     
     
         11 . The exhaust aftertreatment system of  claim 8 , wherein said EGI radiator cooling fluid circuit passes through a first radiator coil in said radiator and said engine radiator cooling fluid circuit passes through a second radiator coil in said radiator. 
     
     
         12 . The exhaust aftertreatment system of  claim 8 , further comprising a controller to adjust a flow rate of radiator cooling fluid through said EGI radiator cooling fluid circuit. 
     
     
         13 . The exhaust aftertreatment system of  claim 12 , wherein said controller receives as an input a temperature sensed by a thermocouple disposed proximal to an outlet of the exhaust gas intercooler. 
     
     
         14 . The exhaust aftertreatment system of  claim 13 , wherein said controller is in electrical communication with a radiator fluid pump to adjust said flow rate. 
     
     
         15 . The exhaust aftertreatment system of  claim 12 , further comprising a flow control valve disposed in an air injection conduit that extends from an exhaust gas ejector (EGE) to said inlet port, said controller in electrical communication with said flow control valve to adjust an operating position of said flow control valve. 
     
     
         16 . The exhaust aftertreatment system of  claim 15 , further comprising an oxygen sensor disposed in said exhaust conduit between (a) said inlet port in the exhaust conduit and (b) said second catalytic converter, the oxygen sensor outputting an oxygen content of said exhaust to said controller. 
     
     
         17 . The exhaust aftertreatment system of  claim 8 , wherein said air injector comprises an engine charger compressor. 
     
     
         18 . The exhaust aftertreatment system of  claim 17 , wherein said engine charger compressor is a turbocharger compressor or a supercharger compressor. 
     
     
         19 . The exhaust aftertreatment system of  claim 8 , further comprising a gas particulate filter coupled to said exhaust conduit or said second catalytic converter. 
     
     
         20 . The exhaust aftertreatment system of  claim 19 , wherein said gas particulate filter and said second catalytic converter are integrated as a catalyzed gas particulate filter.