Boiler Retrofit for the Utilization of Biodiesel

Abstract

Fuel oil used in the boiler is able to substitute with biodiesel. In lower blends, there are no engine modification needed, but some researchers recommended some technical adjustments in order to maintain the boiler's performance and equipment durability. This study consists of the comparison between the performance of boiler before and after retrofitting on the use of biodiesel. The diesel oil was introduced in biodiesel blends of 10% (B10), 20% (B20) and 25% (B25). A fire tube boiler was used for the test with pressure of 3 bar and heat input capacity of 60,000 kcal. The boiler retrofit is conducted by fine tuning the fan damper scale (FDS) and adding a heating feature on fuel system. It was specifically intended to maintain the quality of combustion and boiler efficiency as well as to avoid an increase in fuel consumption. The combustion behaviour was monitored by exhaust emissions of CO, NOx, and SO₂. The fan damper scale (FDS) and fuel temperature is adjusted by the increasing portion of biodiesel used. The fuel heating apparatus was set at temperature of 40^oC for the use of B10, and 60^oC for B20 and B25. The FDS adjustment was successfully resulted a reduction in rate of combustion air by average of 9.2%. The boiler retrofitting for the utilization of B10, B20 and B25 showed an increase in boiler efficiency by 0.64%, 0.42% and 2.6% respectively. The boiler retrofitting is surprisingly reduced the fuel consumption by average of 11.2%.