Impact of using adulterated automotive diesel on the exhaust emissions of a stationary diesel engine

The EU Directives and legislation by worldwide environmental authorities impose constantly
lower levels for the airborne pollutant emissions of internal combustion engines towards the
goal of zero emission vehicles. During the last decade, engine manufacturers, refiners and
fuel companies invest highly in order to comply with the increasingly severe emission
requirements.
The diesel engine is widely used for transportation, manufacture, power generation,
construction and farming operations. There are different kinds of diesel engine depending on
their application: small, high speed, indirect-injection engines or low speed, direct -injection
behemoths with cylinders more than one meter in diameter. Their main advantages are the
efficiency, economy and reliability. The physicochemical properties of the diesel fuels and the
engine design affect the operability, the efficiency and the performance of the diesel engine
and they correlate to the exhaust emissions.
In Greece, the diesel fuel market steadily increases during the last years. The fuels produced
by the refineries usually comply with the existing specifications. However, alterations in the
fuel properties may occur through the supply chain to the service stations due to failures of
the distribution system (i.e. contamination with water, tank sludge and residues) or
adulteration with lower value and taxation fuels (heating oil, marine diesel or industrial
solvents).
The transportation sector is a major source of air pollution. It contributes to harmful exhaust
emissions, such as greenhouse gas emissions, carbon monoxide, sulfur oxides (SOx),
nitrogen oxides (ΝΟx), unburned hydrocarbons (HC) and particulate matter (PM) emissions.
In this paper, PM and exhaust emissions from a stationary single cylinder diesel engine were
examined. For comparison purposes, tests were carried out with a typical automotive diesel
fuel of the Greek market and with adulterated fuels with heating oil or white spirit. The noncomplying
diesel fuels gave increased emissions in all cases with only exception the PM
emissions due to adulteration with white spirit. More specifically, the experimental results for
the adulterated fuels with heating diesel showed an increase of the nitrogen oxide emissions
up to 73.9%, of the unburned hydrocarbons up to 29.6% and of PM up to 121% compared to
the baseline diesel fuel emissions.