2015 年 30 巻 2 号 p. 100-107
Diesel engines have contributed in industry and transportation because of high energy efficiency and durability. The serious drawback of diesel engines is emission of PM and gaseous pollutants, especially NOx. Due to tough regulation of emission, high efficiency and low pressure-drop apparatus for diesel exhaust after-treatment has been required. A potential candidate is an electrostatic precipitation, ESP, for PM (particulate matter) and non-thermal plasma, NTP, process for gaseous pollutants. Due to low electrical conductivity, diesel PM is difficult to remove. In this article, some of novel attempt in ESPs are introduced, together with the effectiveness of the combination of ESP and DPF (Diesel particulate filter).For regeneration, or oxidation of PM deposit, of DPF at low temperature condition can be possible using NTP in DPF. NO in exhaust gas can also be oxidized using NTP, resulting in higher removal efficiency of NOx using SCR (selective catalytic reduction) with ammonia. The engine test using JE05 mode proved the effectiveness of NTP for the after-treatment.