Particulate emission control for diesel engine by surface discharge electrostatic reactor

Kento Fukui¹, Kohei Kawakami¹, Apeksha Madhukar², Tomoyuki Kuroki¹, Haruhiko Yamasaki¹, Masaaki Okubo^{1, *}

^* The author to whom correspondence should be addressed.

¹ Department of Mechanical Engineering, Osaka Metropolitan University, Japan
² School of Electrical Sciences, Indian Institute of Technology Goa, India

Abstract

Diesel engines have better fuel economy and emit less CO₂ than gasoline engines. However, because their exhaust gas contains large amounts of nitrogen oxides (NO_x), particulate matter (PM), and hydrocarbons (HC), aftertreatment is necessary. We use a new plasma aftertreatment method to remove PM in the exhaust gas. Particle concentrations are measured before and after plasma treatment using a scanning mobility particle sizer (SMPS) and a laser particle counter (LPC). The engine load is set to 0%, 24%, 48%, and 72% using electric heaters. The exhaust gas is diluted with N₂ + O₂ mixed gas (O₂ concentration 13%), and the mixed gas flow rate is adjusted to 5, 10, and 15 L min^-1. The input power of the reactor is adjusted to 100, 200, 300, and 400 W. PM removal performance is measured, and the removal efficiency is 83% or more under all conditions. At flow rates of 5 and 10 L min^-1, a removal efficiency of 95% or more is obtained. At a flow rate of 15 L min^-1, 48% load, and input power of 100W, a removal efficiency of 95% or more is obtained. At a flow rate of 15 L min^-1, the removal efficiency decreases under several conditions. Under these conditions, the residence time is short due to the high flow rate. It is also considered that sufficient removal is not achieved due to the large number of particles before treatment and the low discharge power. The increase in small particles reduces the removal efficiency in the small particle size range. Since previous studies have achieved high removal efficiencies of 67% NO_x and 76% HC using equipment and conditions similar to those of this device, we believe that this surface discharge electrostatic reactor can achieve highly efficient simultaneous removal of PM, NO_x, and HC.

Keywords - Diesel Engine, plasma, NO_x, PM, HC, simultaneous removal.

[Full text PDF]

Citation
BibTeX
RIS

Back to table of contents