Method and Device for Addition of a Reducing Agent in an Exhaust Gas Line of an Internal Combustion Engine of a Motor Vehicle

Abstract

The invention relates to a method and a device for the addition of a reducing agent in an exhaust gas line of an internal combustion engine of a motor vehicle, with at least one NO x storage catalyst that is arranged in the exhaust gas line of the internal combustion engine, and with a metering device, by means of which a preset amount of a reducing agent is introduced into the exhaust gas line at preset times. The metering device is created from a stationary gas line connecting element that is made up of multiple parts at a defined position on the exhaust gas line and a connecting counter-element that can be connected in a detachable manner to this connecting element and that can be arranged independently of the exhaust gas line and motor vehicle, in particular removed from the motor vehicle, in such a way that the connecting counter-element, during service, in particular when the motor vehicle is parked and/or the internal combustion engine is idling, is connected to the exhaust gas line connecting element, and then, for purposes of regeneration of at least one NO x storage catalyst for a preset time, a preset amount of reducing agent is introduced into the exhaust gas line. After the regeneration, the connecting counter-element is again detached from the exhaust gas line connecting element and stored at a preset location.

1 . A method for the addition of a reducing agent in an exhaust gas line of an internal combustion engine of a motor vehicle,
 with at least one NO x  storage catalyst that is arranged in the gas line of the internal combustion engine, and   with a metering device, by means of which a preset amount of a reducing agent is introduced into the exhaust gas line at preset times, wherein   the metering device is created from a stationary gas line connecting element that is made up of multiple parts at a defined position on the exhaust gas line and a connecting counter-element that can be connected in a detachable manner to this connecting element and that can be arranged independently of the exhaust gas line and motor vehicle and in particular removed from the motor vehicle, in such a way that the connecting counter-element, for service, in particular when the motor vehicle is parked and/or the internal combustion engine is idling, is connected to the exhaust gas line connecting element, and then, for purposes of regeneration of at least one NO x  storage catalyst for a preset time, a preset amount of reducing agent is introduced into the exhaust gas line, whereby after the regeneration, the connecting counter-element can again be detached from the exhaust gas line connecting element.   
   
   
       2 . The method according to  claim 1 , wherein the internal combustion engine is operated with a fuel whose sulfur content is less than or equal to 30 ppm, in particular less than or equal to 10 ppm. 
   
   
       3 . The method according to  claim 1 , wherein the reducing agent is a mixture of substances with a sulfur content of less than or equal to 30 ppm, in particular less than or equal to 10 ppm. 
   
   
       4 . The method according to one of  claims 1 , wherein the reducing agent is heated to a preset reducing agent temperature before the addition. 
   
   
       5 . The method according to one of  claims 1 , wherein the regeneration speed of the internal combustion engine that is preset for service or regeneration is the idle speed of the internal combustion engine. 
   
   
       6 . A device for the addition of a reducing agent in an exhaust gas line of an internal combustion engine of a motor vehicle, with at least one NO x  storage catalyst that is arranged in the exhaust gas line of the internal combustion engine, and
 with a metering device, by means of which at preset times, a preset amount of a reducing agent can be introduced into the exhaust gas line, wherein the metering device is created from a stationary gas line connecting element that is made up of multiple parts at a defined position on the exhaust gas line and a connecting counter-element that can be connected in a detachable manner to this connecting element and that can be arranged independently of the exhaust gas line and motor vehicle, in particular removed from the motor vehicle.   
   
   
       7 . The device according to  claim 6 , wherein the connecting counter-element is a component of a stationary or mobile desulfurization device that is arranged at a service facility or an auto repair shop. 
   
   
       8 . The device according to  claim 6 , wherein the connecting counter-element and the exhaust gas line connecting element are connected to one another in a detachable manner with a quick-coupling connection that is designed to be gas-tight and/or liquid-tight when in the connected state. 
   
   
       9 . The device according to  claim 7 , wherein the desulfurization device has a reducing agent reservoir for a reducing agent as well as a control and/or regulating device for defined charging of the exhaust gas line with a reducing agent. 
   
   
       10 . The device according to  claim 9 , wherein the desulfurization device has a line connection, in particular a hose line connection, between the reducing agent reservoir and the connecting counter-element, and wherein the control and/or regulating device is coupled indirectly or directly into the hose line connection in the area between the connecting counter-element and the reducing agent reservoir. 
   
   
       11 . The device according to one of  claims 7 , wherein the desulfurization device has a heating device by means of which the reducing agent can be heated to a preset temperature. 
   
   
       12 . The device according to one of  claims 6  wherein the exhaust gas line connecting element is arranged in the exhaust gas line in the area between a diesel particle filter and an NO x  storage catalyst. 
   
   
       13 . A method of desulferizing the catalytic converter of a motor vehicle comprising:
 detachably connecting a fluid line to a portion of the exhaust gas line of said vehicle, between the engine and catalytic converter thereof, when said vehicle is located at a selected site; and   introducing a sulfur reducing agent into said exhaust gas line, through said fluid line.   
   
   
       14 . A method according to  claim 13  including operating said engine under a selected condition during introduction of said agent. 
   
   
       15 . A method according to  claim 13  including heating said reducing agent. 
   
   
       16 . A method according to  claim 13  including introducing said agent for a selected period of time. 
   
   
       17 . A system for desulferizing the catalytic converter of a motor vehicle comprising:
 means for holding supply of a sulfur reducing agent at a selected site, provided with a line for dispensing said agent, detachably connectable to a portion of the exhaust gas line between the engine and the catalytic converter of a vehicle situated at said selected site; and   means for metering a supply of said agent through said dispensing line.   
   
   
       18 . A system according to  claim 17  including means for heating said agent. 
   
   
       19 . A system according to  claim 17  wherein said dispensing line and said portion of said exhaust gas line are provided with fluid coupling members,