An engine system lubricated by means of a lubrication oil that forms ammonia-soluble ash when combusted, and a vehicle comprising such an engine system

Abstract

An engine system comprising an internal combustion engine operated by a fuel and lubricated by a lubrication oil comprising at least one additive that renders ash formed by combustion of the lubrication oil ammonia-soluble ash; an exhaust gas system for cleaning an exhaust gas flow from the internal combustion engine , the exhaust gas system comprising a diesel particulate filter to capture particulate matter from the exhaust gases, wherein the particulate matter comprises the ammonia-soluble ash; an exhaust gas conduit to lead exhaust gases from the internal combustion engine through the exhaust gas system; and an injection device to add a solvent comprising ammonia or an ammonia-forming compound into the exhaust gas flow upstream of the diesel particulate filter, wherein the exhaust gas conduit collects the solvent and lead the solvent through the diesel particulate filter, thereby dissolving and thus removing the ammonia-soluble ash from the diesel particulate filter.

1 . An engine system comprising:
 an internal combustion engine arranged to be operated by a fuel and to be lubricated by a lubrication oil comprising at least one additive that renders ash formed by combustion of the lubrication oil ammonia-soluble ash;   an exhaust gas system for cleaning an exhaust gas flow from the internal combustion engine, the exhaust gas system comprising a diesel particulate filter arranged to capture particulate matter from the exhaust gases, wherein the particulate matter comprises the ammonia-soluble ash;   an exhaust gas conduit arranged to lead exhaust gases from the internal combustion engine through the exhaust gas system; and   an injection device arranged to add a solvent comprising ammonia or an ammonia-forming compound into the exhaust gas flow upstream of the diesel particulate filter,   wherein the exhaust gas conduit is arranged to collect the solvent and lead the solvent through the diesel particulate filter, thereby dissolving and thus removing the ammonia-soluble ash from the diesel particulate filter.   
     
     
         2 . An engine system according to  claim 1 , wherein that the injection device comprises a valve which is fluidly connected to a solvent reservoir, wherein the solvent is arranged to be fed from the solvent reservoir to the injection device by means of a feeding pump. 
     
     
         3 . An engine system according to  claim 1 , wherein the injection device is further arranged to inject a reducing agent into the exhaust gas flow upstream of the diesel particulate filter. 
     
     
         4 . An engine system according to  claim 3 , wherein the solvent is the reducing agent and the solvent reservoir also constitutes a reservoir for the reducing agent. 
     
     
         5 . An engine system according to  claim 3 , wherein the injection device comprises a valve arranged to be positioned in a first position in which it is arranged to inject the reducing agent into the exhaust gas flow and a second position in which it is arranged to inject the solvent into the exhaust gas flow. 
     
     
         6 . An engine system according to  claim 1 , wherein the engine system further comprises a control system arranged to control the operation of the injection device. 
     
     
         7 . An engine system according to  claim 6 , wherein the control system is arranged to control the operation of the injection device at pre-determined intervals and/or pre-determined conditions. 
     
     
         8 . An engine system according to  claim 7 , wherein the exhaust gas system further comprises a first sensor arranged upstream of the diesel particulate filter for measuring a pressure drop over the diesel particulate filter or a pressure of the exhaust gas flow before filtration, and the first sensor is connected to the control system. 
     
     
         9 . An engine system according to  claim 8 , wherein the control system comprises means arranged to compare the measured pressure drop value or the value for the pressure of the exhaust gas flow with a predetermined value for the pressure drop or the pressure of the exhaust gas flow and create an error code if the pressure drop value or the pressure value differs from the predetermined value. 
     
     
         10 . An engine system according to  claim 8 , wherein the exhaust gas system comprises a second sensor arranged downstream of the diesel particulate filter for measuring the pressure of the exhaust gas flow after filtration and the second sensor is connected to the control system. 
     
     
         11 . An engine system according to  claim 10 , wherein the control system comprises means arranged to calculate a pressure drop over the diesel particulate filter from the received measuring signals from the first sensor and the second sensor. 
     
     
         12 . An engine system according to  claim 11 , wherein the control system comprises means arranged to compare the calculated pressure drop value with a predetermined pressure drop value and create an error code if the measured pressure drop value differs from the predetermined value. 
     
     
         13 . An engine system according to  claim 8 , wherein the control system comprises means arranged to control the injection device so as to add the solvent into the exhaust gas flow. 
     
     
         14 . An engine system according to  claim 13 , wherein the control system further comprises means arranged to control the internal combustion engine or the engine system based on the measured or calculated pressure drop value or value for the pressure of the exhaust gas flow so as to increase an amount of condensed water. 
     
     
         15 . A vehicle comprising an engine system comprising:
 an internal combustion engine arranged to be operated by a fuel and to be lubricated by a lubrication oil comprising at least one additive that renders ash formed by combustion of the lubrication oil ammonia-soluble ash;   an exhaust gas system for cleaning an exhaust gas flow from the internal combustion engine, the exhaust gas system comprising a diesel particulate filter arranged to capture particulate matter from the exhaust gases, wherein the particulate matter comprises the ammonia-soluble ash;   an exhaust gas conduit arranged to lead exhaust gases from the internal combustion engine through the exhaust gas system; and   an injection device arranged to add a solvent comprising ammonia or an ammonia-forming compound into the exhaust gas flow upstream of the diesel particulate filter,   wherein the exhaust gas conduit is arranged to collect the solvent and lead the solvent through the diesel particulate filter, thereby dissolving and thus removing the ammonia-soluble ash from the diesel particulate filter.   
     
     
         16 . A vehicle according to  claim 15 , wherein the injection device comprises a valve which is fluidly connected to a solvent reservoir, wherein the solvent is arranged to be fed from the solvent reservoir to the injection device by a feeding pump. 
     
     
         17 . A vehicle according to  claim 15 , wherein the injection device is further arranged to inject a reducing agent into the exhaust gas flow upstream of the diesel particulate filter. 
     
     
         18 . A vehicle according to  claim 17 , wherein the solvent is the reducing agent and the solvent reservoir also constitutes a reservoir for the reducing agent. 
     
     
         19 . A vehicle according to  claim 17 , wherein the injection device comprises a valve arranged to be positioned in a first position in which it is arranged to inject the reducing agent into the exhaust gas flow and a second position in which it is arranged to inject the solvent into the exhaust gas flow. 
     
     
         20 . A vehicle according to  claim 15 , wherein the engine system further comprises a control system arranged to control the operation of the injection device.