Analysis of Exhaust Gases and Soot Collected from The Automobile Engine Operated with Biodiesel and Diesel

Abstract

The objective of this study is to compare engine performance, exhaust gases and soot of biodiesel and diesel. In the present work, with same test engine the perfor- mance of biodiesel and diesel has been investigated with di erent aspects namely, engine performance, exhaust gas and soot particle analysis. Some preliminary exper- iments have been conducted to optimized the engine parameters namely, compression ratio and injection timing. For the best performance we found CR 18 and 15° BTDC is the best for complete combustion. We set these parameters on the test engine and perform experiments on engine to nd out emission of di erent gases and to collect soot using biodiesel and diesel as a fuel. Further experiments using biodiesel and diesel have been conducted with engine test rig for performance testing like fuel consumption (BSFC), Break power (BP), Break Thermal E ciency (BTHE), Mechanical e ciency and Air Fuel ratio. For both biodiesel and diesel mechanical e ciency increases with increasing the load on engine. It is also observed that the mechanical e ciency of diesel is higher compare to biodiesel. Apart from these ex- periments, according to the objectives the exhaust gas from the engine like CO2, CO, O2, HC, NOx and metal emission like Al, Fe, Mg, Cr, Ca, Zn and Pb have been analyzed for both biodiesel and diesel. Regarding to the metal emission, biodiesel emits less heavy metals in engine exhaust compared to diesel. For both biodiesel and diesel the exhaust soot is also critically analyzed and discussed. We also compare the particle size, structure of the particle for di erent engine load condition using diesel and biodiesel as a fuel. At full load in the both cases total organic carbon is approximately same. The engine exhaust soot consists of total organic carbons and di erent metals. It is observed that the average particle size of biodiesel exhaust is smaller compare to that of diesel. Study revealed that particle size of biodiesel and diesel is in the range of 40- 50 nanometre. The transmission electron microscope (TEM) images shows the strong agglomeration of soot particles in the samples and similar observations are also noticed in the results obtained using particle size distribution analyzer and scanning electron microscope (SEM) micrographs. At full load condition, total organic carbon (TOC) is about 78.53% and 80.01% by weight for biodiesel and diesel, respectively. Combustion phenomenon of biodiesel is approximately same as that of fossil diesel. So biodiesel can be directly used in the diesel engine without any modi cation in the diesel engine.