Performance evaluation of PM, NOx, and hydrocarbon removal in diesel engine exhaust by surface discharge-induced plasma

Kohei Kawakami; Ken Watatani; Haruhiko Yamasaki; Tomoyuki Kuroki; Masaaki Okubo

doi:10.1016/j.jhazmat.2023.132685

Performance evaluation of PM, NO_x, and hydrocarbon removal in diesel engine exhaust by surface discharge-induced plasma

J Hazard Mater. 2024 Jan 15:462:132685. doi: 10.1016/j.jhazmat.2023.132685. Epub 2023 Oct 4.

Authors

Kohei Kawakami¹, Ken Watatani², Haruhiko Yamasaki³, Tomoyuki Kuroki³, Masaaki Okubo⁴

Affiliations

¹ Department of Mechanical Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan.
² Department of Mechanical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan.
³ Department of Mechanical Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan; Department of Mechanical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan.
⁴ Department of Mechanical Engineering, Osaka Metropolitan University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan; Department of Mechanical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai 599-8531, Japan. Electronic address: mokubo@mokubo.com.

PMID: 37862904
DOI: 10.1016/j.jhazmat.2023.132685

Abstract

Diesel engines are characterized by low CO₂ emissions and high fuel efficiency. However, their exhausts contain nitrogen oxides (NO_x), particulate matter (PM), and hydrocarbons (HC) that require removal by aftertreatment. A novel low-temperature plasma-based aftertreatment method has been developed for the simultaneous removal of NO_x, PM, and HC. NO_x could be reduced by reacting with HC and CO in the exhaust gas. The particle and gas concentrations in the exhaust are measured using a scanning mobility particle sizer, a NO_x analyzer, and a total hydrocarbon analyzer. The treatment performance is evaluated using the resulting measurements. The diesel engine is operated under 0%, 25%, 50%, and 75% loads (maximum output of 2 kW), and the exhaust gas is mixed with N₂ + O₂ (13%) gas. The power is adjusted to provide 100, 200, 300, and 400 W input power during the plasma reactor treatment. The aftertreatment removal of NO_x, PM, and HC is evaluated, and the engine exhibits a removal efficiency of 70% for NO_x, 98% for PM, and 67% for HC at 75% engine load and an input power of 100 W.

Keywords: Diesel engine; Hydrocarbon; NO(x); PM; Surface discharge plasma.