SAFARI BSVI SERVICE MANUAL

KRYOTEC ENGINE 117 P. EXHAUST SYSTEM LAYOUT COMPONENTS Exhaust after treatment consists of mainly: Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), Selective Catalyst Reduction (SCR) and various sensors and actuators. The exhaust gas coming from the engine first passes through the DOC. It then flows through DPF. DPF is a filter which filters carbon soot in the exhaust gas. DOC and DPF contains precious metals which converts hydrocarbons, carbon monoxide etc. in the exhaust gas to harmless constituents. Additionally DPF also removes most of the carbon soot particles in the exhaust gas. The collected carbon soot in the DPF is regenerated to clean the filter. In order to reduce the NOx levels even further, SCR system is used. In SCR system, Diesel Exhaust Fluid (DEF) is injected in the exhaust stream. With the help of injected ammonia in the Diesel Exhaust Fluid (DEF), NOX is also converted into harmless constituents. DIESEL OXIDATION CATALYST (DOC) The exhaust coming from the engine first passes through the DOC. It is flow through filter that contains precious metals to start the oxidation of hydrocarbons, carbon monoxide and unburned fuel and oil. It is mainly used for oxidizing nitrogen oxide (NO) to nitrogen dioxide (NO2), substances that together create NOx. When exhaust gases passed over an oxidation catalyst, carbon monoxide (CO), hydrocarbons (HC), the organic fraction of diesel particulates (OF), as well as non-regulated emissions such as aldehydes or PAHs can be oxidized to harmless products. DIESEL PARTICULATE FILTER (DPF)