EHD-assisted plasma electrostatic precipitator for simultaneous PM collection and incineration

The electrohydrodynamically-assisted (EHD) plasma electrostatic precipitator (called plasma ESP hereafter) was developed not only to collect low-resistive fine particles generated from diesel engine but also to incinerate captured particulates within the same reactor. The plasma ESP is to utilize EHD to transport the charged particles effectively into the low electrostatic field region where electrostatic repulsion force acting on particles by induction charge is very small, resulting in suppression of PM reentrainment. At the same time, collected particulates are incinerated by ozone and oxidation product of NO2 in the flue gas by the surface discharge plasma in the same unit so that no particle storage and handling device are required. The particle-size dependent collection efficiency and particle incineration were evaluated by the Scanning Mobility Particle Sizer (SMPS) for particle size of 20-500 nm and the particle counter (PC) for particle size of 300-5,000 nm. The results indicated that the plasma ESP was able to collect more than 90 % collection efficiency and no reentrainment occurred for all particle size measured. The plasma ESP leads to more economical and compact ESP feasible. No PM handling device and storage are required and therefore has high potential for marine engine and automobiles.