Effects of oxygen addition on thermal and pollutant emission characteristics of a cylindrical furnace fueled with 1-Hexanol–biodiesel–diesel blends

Abstract

This study aims to investigate the combined effects of oxygen addition to inlet air and utilization of 1-Hexanol, biodiesel, and diesel blends on the thermal and emission characteristics of a cylindrical furnace. The design of experiments was used based on the presence of three-composite fuels and the oxygen inlet flow as independent variables. The experimental tests were conducted on a cylindrical furnace equipped with a diesel burner. The results showed that the combustion temperature increased by up to 11 °C with the increase in the flow rate of oxygen addition. Moreover, the results indicated that with an increase in oxygen addition flow rate, the HC and CO emissions decreased by almost 33% and 18%, respectively. However, there was no significant effect on CO2 emissions. On the other hand, the amount of NOx emissions increased with oxygen addition flow rate by approximately 12.5%. According to the results, the increase in the percentage of biodiesel and hexanol caused an increase in NOx emissions and a reduction in CO and HC emissions. And, the fuel mixture with 50% diesel, 30% biofuel, and 20% 1-Hexanol (D50B30H20) had the maximum NOx emissions and the minimum HC and CO emissions in comparison with other fuel mixtures for all oxygen addition flow rates. The results also indicated that increasing the percentage of biofuels in the fuel mixture, along with an increase in the rate of oxygen addition, leads to a higher reduction rate of HC and CO emissions. Furthermore, oxygen flow rates higher than 5 liters per minute did not significantly affect the formation of CO2 emissions, but prevented the formation of NOx.