Electrostatic Precipitators for Cleaning Diesel Exhaust

Electrostatic precipitators have been applied for pre-charging dust particles suspended in diesel exhaust. Followed by a diesel particulate filter (DPF), nano-size particles can be removed from the gas stream efficiently. Removed particles from the gas stream can be oxidized at 600 degree C. However, heat stress occasionally breaks DPF, and low temperature oxidation below 200 degree C is preferable. The purpose of this study is to evaluate the oxidation ability of ozone to diesel exhaust particulate (DEP) at low temperatures. At 200 degree C, O₃ can oxidize simulated carbon particle. At room temperature, however, the oxidation is slow and incomplete. The result suggests that ozone can be used for low temperature oxidation of soot but its energy efficiency is low.