Soot Particle Size Distribution, Regulated and Unregulated Emissions of a Diesel Engine Fueled with Palm Oil Biodiesel Blends

Jun Cong Ge,Nag Jung Choi

doi:10.3390/en13215736

Abstract

In this study, five fuels including pure diesel (B0), pure palm oil biodiesel (B100), and their blends (B10, B20, and B30) were investigated in relation to soot particle distribution and regulated and unregulated emission characteristics in a common rail direct injection (CRDI) diesel engine. The results indicated that CO, hydrocarbon (HC), and particulate matter (PM) regulated emissions were effectively controlled to a very low level by combining the addition of palm oil biodiesel (POB) to diesel with optimized engine operating conditions. Paper filters and TEM grids were used to capture the diesel particles. All the PM primary particles were less than 100 nm in diameter observed by TEM, and the average diameters of the PM primary particles for the biodiesel blends were distributed between 20 and 26 nm. Unregulated emissions such as trace metals including Pb, Mn, and Ba were found in the PM particles, and the xylene, toluene, and benzene unregulated emissions of B100 were reduced by 55.68%, 21.56%, and 18.32%, respectively, compared to those of B0. Therefore, POB is an excellent alternative fuel for diesel engines and has great application potential to solve the current pollution problems of regulated and unregulated emissions.

Highlights

Diesel engines have been used widely in applications such as commercial vehicles, passenger cars, power generators, and construction equipment due to their high thermal efficiency, reliability, and large output power [1,2]
TEM, and the average diameters of the particulate matter (PM) primary particles for the biodiesel blends were distributed between 20 and 26 nm. Unregulated emissions such as trace metals including Pb, Mn, and Ba were found in the PM particles, and the xylene, toluene, and benzene unregulated emissions of B100 were reduced by 55.68%, 21.56%, and 18.32%, respectively, compared to those of B0
The peak in-cylinder pressure (IP) of all tested fuels appeared after top dead center (ATDC) 8◦ ~15◦ crank angle (CA) under all operating conditions

Summary

Introduction

Diesel engines have been used widely in applications such as commercial vehicles, passenger cars, power generators, and construction equipment due to their high thermal efficiency, reliability, and large output power [1,2]. High nitrogen oxide (NOx) and particulate matter (PM) emissions are significant drawbacks of diesel engines [3,4]. It is well known that the relationship between PM and NOx emissions is a tradeoff, which makes it difficult to reduce PM and NOx simultaneously using traditional engine technology. Some new combustion technology, such as low temperature combustion (LTC) [6] and diesel exhaust aftertreatment devices (e.g., DOC: Diesel Oxidation Catalyst; DPF: Diesel Particulate Filter; and SCR: Selective Catalytic Reduction) [7], can limit the regulated emissions (i.e., CO, hydrocarbon (HC), NOx, and PM) to a low value, they will increase purchase and maintenance costs, which is uneconomical

Methods

Results

Conclusion