Resumo:
The growing global demand for power generation using renewable energy sources is
fundamental for the longevity of modern civilization. With the prospects for mitigating the
environmental impacts arising from fuels, technological solutions are needed from the scientific
community to promote the maximization of fuel conversion efficiency and the reduction of
pollutant emission levels in internal combustion engines. Concerning biofuels, the use of
biomass and wastes as sources of energy are interesting options, as they are abundant resources
and present an approximately neutral CO2 emission cycle. In this context, this work aimed to
develop an experimental setup to study the combustion, performance and pollutant emissions
of a single-cylinder compression ignition engine, using renewable diesel from sugarcane
(Farnesane) and waste cooking oil (WCO) biodiesel. The methodology consisted of the
development of the test bench with all instrumentation, preparation and characterization of
biofuels, methods of data analysis and measurement uncertainties calculation, and analysis of
parameters of interest. Moreover, the testing procedure aimed at the application of small scale
motor-generators. Experiments were divided into two stages: tests using Farnesane compared
to conventional Diesel and tests using Farnesane with WCO biodiesel. Additionally, external
and cooled exhaust gas recirculation (EGR) was applied and its influence analyzed. The results
obtained with Farnesane presented lower values of ignition delay, peak heat release rate and
diffusive combustion duration, with fuel conversion efficiency gains of up to 5.9% compared
to Diesel. Furthermore, reduced levels of NOx, HC, CO and particulate matter (PM) emissions
were achieved. Farnesan with EGR application, mainly through the dilution and thermal effects,
improved the NOx-PM trade-off, as Farnesane further reduced the NOx emissions level up to
48.6% and presented PM values around 75% lower than conventional diesel combustion. The
results of the 10% and 20% by volume addition of WCO biodiesel to Farnesane showed
technical potential for operation and emission reduction compared to conventional diesel,
favoring the already consolidated production and distribution chain of biodiesel and the national
tendency to use the renewable diesel blended with waste-derived biodiesel.
