LiuGong CLG835H, Service Manual

Page: 67 / 764

2-29
January 24, 2017 Structure Function Principle
CLG835H Diesel Particle Filter System
Diesel Particle Filter System
Part Structure and Principle Introduction
The main function of DPF (Diesel Particle Filter) is to reduce the harmful substance of engine exhaust in
order to conform with emission standard. Particulates and NOx emission of the model conform with the
emission standard of Tier 4Final/Euro Stage IV.
Terminology:
DOC: Diesel Oxidation Catalyst
SCR: Selective Catalytic Reduction
Diesel particle filter of the model adopts DOC+SCR routine. When exhaust passes DOC, under the
function of catalyzer, hydrocarbon HC is oxidized to CO2 and water. When exhaust passes SCR, nitride
oxides NOx is reduced to nitrogen and water.
The reaction in the DOC:
HC (Hydrocarbon Compounds ) + O2
→
H
2
O + CO
2
The reaction in the SCR:
NO
x
(nitrogen oxides) + NH
3
(a O
2
→
(catalytic reaction)
→
N
2
+ H
2
O.
1. DOC 2. DEF nozzle 3. SCR
P18P00038
Exhaust
1
2
3