The research on post-treatment of diesel engine exhaust revolves around the elimination of NOX and PM.And so many purification measures have emerged. The diesel exhaust purification technology mainly includes exhaust gas recirculation (EGR), oxidation catalytic converter (DOC), diesel particulate filter (DPF), selective catalytic reduction system (SCR), and ammonia escape trap (ASC).
1.EGR (Exhaust Gas Re circulation) exhaust gas recirculation system, which separates a portion of the exhaust gas from the combustion engine and introduces it into the intake side for further combustion, can achieve the effect of suppressing the production of nitrogen oxides and improving fuel economy
2.DOC (Diesel Oxidation Catalyst) is a diesel oxidation catalyst technology that uses catalysts containing precious metals to further oxidize HC, CO, NO, and volatile costs on particle surfaces in engine exhaust, thereby reducing the amount of HC, CO, and PM.
3.DPF (Diesel Particulate Filter) is a type of filter installed in the exhaust system of diesel engines, mainly used to capture particulate matter (PM) in the exhaust.
4.SCR (Selective Catalytic Reduction) system is a technology that uses urea to selectively reduce nitrogen oxides (toxic gases) in exhaust gas into nitrogen and water (which are harmless).
5.ASC (Ammonia Slip Catalyst) ammonia escape catalyst, some trucks' National VI post-treatment will have ASC system, which is installed at the rear end of SCR and reduces the leakage of ammonia (NH3) in the exhaust of SCR rear end through catalytic oxidation.
6.POC is a particulate catalytic oxidizer. The working principle is to pick up particulate matter and burn it off through the high temperature of exhaust gas (250 ℃ -500 ℃) to achieve the goal of reducing particulate matter. POC is commonly used on light trucks. In addition, POC can be actively regenerated, while DPF requires manual intervention.
Post time: Jul-31-2024