Complex analysis focused on influence of biodiesel and its mixture on regulated and unregulated emissions of motor vehicles with the aim to protect air quality and environment

Abstract

The main task of this study is to perform a complex analysis dealing with influence of biodiesel and its mixture on regulated and unregulated gaseous emissions of diesel engine, which is installed in a motorcar as a driving unit determined for standard road traffic. As a real technical platform intended for realisation of the required experiments, a motor vehicle equipped with the TDI engine was chosen because just this kind of engine was directly affected by the affair “dieselgate”. This type of piston combustion engine is widely used in the traffic, together with negative impacts on the air quality. Various diesel fuel mixtures, which represented the applied experimental fuels, were created by mixing of the ultra-low sulphur diesel fuel (ULSDF) with the biodiesel, using different mixture ratios. The individual experiments were performed during a 13-mode test cycle especially developed for the diesel engine in such a way, so that it was possible to identify influence of the engine loading and engine speed on the regulated and unregulated gaseous emissions of the given TDI diesel engine. It is possible to say according to the obtained results that a higher portion of the biodiesel in the fuel mixture reduces the amount of the hydrocarbons (HC), carbon monoxide (CO) and particulate matters (PM) in the gaseous emissions, but it increases volume of the nitrogen oxides (NOX). A higher portion of the biodiesel causes a growth of the formaldehyde emissions and acetaldehyde emissions in the case of unregulated diesel engine emissions. The same trend is also typical for the 1,3-butadiene, propene and ethene. The biodiesel additive increases emissions of benzene; however, it reduces emissions of the toluene and xylene within the aromatic substance emissions. The obtained results confirm a fact that all the gaseous emissions are influenced by the engine operational regimes, especially by the engine loading status.