Exhaust gas post-processing apparatus and method for sulfur oxide removal

Abstract

The present disclosure relates to an apparatus and a method of post-processing exhaust gas for removing sulfur oxides, and more particularly, relates to an apparatus and a method of post-processing exhaust gas for removing sulfur oxides, in which exhaust gas is produced when fuel is combusted in a diesel internal combustion engine and the exhaust gas is purified by the apparatus for post-processing exhaust gas, and in this case, sulfur oxides (SOx) is produced and stacked in a catalytic device (diesel oxidation catalyst (DOC) and selective catalytic reduction (SCR)) equipped in the apparatus for post-processing exhaust gas during a process of purifying the exhaust gas, and the sulfur oxides is removed.

1 . An apparatus for post-processing exhaust gas for removing sulfur oxides, the apparatus comprising:
 an input unit configured to receive one or more elements of operation information of a vehicle among an engine operation time, an engine fuel consumption quantity, a vehicle trip distance, and sulfur oxides produced quantity;   a memory unit configured to store a first operation information value for processing sulfur oxides and a second operation information value for processing sulfur oxides, wherein the first operation information value and the second operation information value are generated by evaluating the operation information received from the input unit;   a first processing unit configured to determine whether the first operation information value stored in the memory unit reaches a predetermined first reference value, and to generate a low temperature control command when the first operation information value reaches the first reference value;   a second processing unit configured to determine whether the second operation information value stored in the memory unit reaches a predetermined second reference value, and to generate a high temperature control command when the second operation information value reaches the predetermined second reference value; and   a sulfur oxides removal operating unit configured to remove a first sulfur oxides by heating a catalytic device under a first temperature condition when the low temperature control command is generated from the first processing unit, and remove the first sulfur oxides and a second sulfur oxides by heating the catalytic device under a second temperature condition when the high temperature control command is generated from the second processing unit.   
     
     
         2 . The apparatus of  claim 1 , wherein the first processing unit initializes the first operation information value of the memory unit after the low temperature control command is generated, and
 the second processing unit initializes the second operation information value of the memory unit after the high temperature control command is generated.   
     
     
         3 . The apparatus of  claim 2 , wherein when the second processing unit initializes the second operation information value of the memory unit, the second processing unit also initializes the first operation information value of the memory unit. 
     
     
         4 . The apparatus of  claim 1 , wherein in the sulfur oxides removal operating unit, the first temperature condition is 400° C. or higher and the second temperature condition is 600° C. or higher. 
     
     
         5 . The apparatus of  claim 1 , wherein the predetermined first reference value is smaller than the second reference value. 
     
     
         6 . The apparatus of  claim 1 , further comprising:
 a manual control unit configured to generate the high temperature control command,   wherein when the high temperature control command is generated from the manual control unit, the first sulfur oxides and the second sulfur oxides are removed by heating the catalytic device under the second temperature condition, and the first operation information value and the second operation information value of the memory unit are initialized.   
     
     
         7 . The apparatus of  claim 1 , wherein the first sulfur oxides includes ammonium sulfate ((NH4)2SO4), and the second sulfur oxides includes copper sulfate (CuSO4). 
     
     
         8 . A method for post-processing exhaust gas for removing sulfur oxides, the method comprising:
 an input operation of receiving one or more elements of operation information of a vehicle among an engine operation time, an engine fuel consumption quantity, a vehicle trip distance, and sulfur oxides produced quantity from an input unit;   an evaluating operation of generating a first operation information value for processing sulfur oxides and a second operation information value for processing sulfur oxides by evaluating the operation information received from the input operation;   a first command operation of determining whether the first operation information value evaluated in the evaluating operation reaches a predetermined first reference value, and generating a low temperature control command when the first operation information value reaches the predetermined first reference value;   a second command operation of determining whether the second operation information value evaluated in the evaluating operation reaches a predetermined second reference value, and generating a high temperature control command when the second operation information value reaches the predetermined second reference value;   a first removal operation of removing a first sulfur oxides by heating a catalytic device under a first temperature condition when the low temperature control command is generated in the first command operation; and   a second removal operation of removing the first sulfur oxides and a second sulfur oxides by heating the catalytic device under a second temperature condition when the high temperature control command is generated in the second command operation.   
     
     
         9 . The method of  claim 8 , further comprising:
 initializing the first operation information value after the low temperature control command is generated; and   initializing the second operation information value after the high temperature control command is generated.   
     
     
         10 . The method of  claim 9 , wherein when the second operation information value is initialized, the first operation information value is initialized together. 
     
     
         11 . The method of  claim 8 , wherein when the received operation information is the engine operation time, the second reference value is set to a range from 1.5 times to 20 times the first reference value. 
     
     
         12 . The method of  claim 8 , wherein when the received operation information is the engine fuel consumption quantity, the second reference value is set to a range from 1.5 times to 10 times the first reference value. 
     
     
         13 . The method of  claim 8 , wherein when the received operation information is the vehicle trip distance, the second reference value is set to a range from 1.5 times to 5 times the first reference value. 
     
     
         14 . The method of  claim 8 , wherein when the received operation information is the sulfur oxides produced quantity, the first reference value is sulfur oxides storage quantity of a DOC or a first sulfur oxides storage quantity, and the second reference value is a second sulfur oxides storage quantity. 
     
     
         15 . The method of  claim 8 , wherein the first temperature condition is 400° C. or higher and the second temperature condition is 600° C. or higher. 
     
     
         16 . The method of  claim 8 , wherein the predetermined first reference value is smaller than the second reference value. 
     
     
         17 . The method of  claim 8 , wherein a manual control unit generating the high temperature control command is further included, and
 the method further includes, when the high temperature control command is generated from the manual control unit, removing the first sulfur oxides and the second sulfur oxides by heating the catalytic device under the second temperature condition, and initializing the first operation information value and the second operation information value.   
     
     
         18 . The method of  claim 8 , wherein the first sulfur oxides includes ammonium sulfate ((NH4)2SO4), and the second sulfur oxides includes copper sulfate (CuSO4).