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EXHAUST AFTER TREATMENT SYSTEMS (EATS)
THE EXHAUST AFTER TREATMENT SYSTEM
The Reduction Process • The DOC has a metallic or ceramic substrate with channels through which exhaust directly flows • The DPF is usually located past the DOC in the Exhaust After Treatment System (EATS) • The DPF is larger than the DOC, with a ceramic substrate with small channels that are blocked at alternating ends • Exhaust gas flows through the porous walls of the channels, trapping the solid soot particles within the DPF • The DPF is designed to remove particulate matter and soot from the exhaust • DPFs remove up to 85% of the soot found in diesel exhaust emissions, reaching greater removal levels when paired with a DOC • Selective Catalytic Reduction (SCR) is an active emissions control technology system that injects a liquid-reductant agent, Diesel Exhaust Fluid (DEF), through a special catalyst into the exhaust stream of a diesel engine Post-combustion exhaust gases are treated prior to tailpipe emission in a diesel combustion vehicle. Unburned hydro carbons (or unburned diesel) is trapped by the Diesel Particulate Filter (DPF) and burned with the aid of the Diesel Oxidation Catalyst (DOC). When used in conjunction with an Selective Catalytic Reduction Catalyst (SCR), the resulting emission is primarily a very friendly mixture of Nitrogen and water in the form of steam.
Exhaust gas from DPF Outlet containing Nitrogen Oxides (NO x )
CAC
DEF TANK
SCR CATALYST
DPF
DOC
DEF DOSER
TAILPIPE
HC DOSER
Precisely controlled quantities of 32.5% DEF Solution are injected into the exhaust stream. DEF solution hydrolyzes into ammonia gas which mixes with the exhaust gas.
Ammonia and Nitrogen Oxides react in the Catalyst to form Nitrogen (N 3 ) and water (H 2 O)
ENGINE with EGR
OTR ™ Diesel Particulate Filters and Diesel Oxidation Catalysts are not available for sale in California at this time.
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