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The potential impact of unsaturation degree of the biodiesels obtained from beverage and food processing biomass streams on the performance, combustion and emission characteristics in a single-cylinder CI engine
2019
Chelladorai, Prabhu | Varuvel, Edwin Geo | Martin, Leenus Jesu | Nagalingam, Bedhannan
The purpose of this study is to experimentally investigate the effect of unsaturation of the biodiesels obtained from grapeseed oil, wheat germ oil and coconut oil (reference fuel) for compression ignition (CI) engine application. Fatty acid profile analysis and physio-chemical properties were determined by standard test procedures. Engine testing was carried out in a 5.2-kW single-cylinder CI engine and the combustion, performance and emission characteristics were analysed. The effect of fuel property variation and the combustion reaction kinetics due to unsaturation difference have been discussed. The maximum brake thermal efficiency at full load for diesel was found to be 32.3% followed by 31.3%, 30.2% and 27.4 %, respectively, for coconut biodiesel (CBD), grapeseed biodiesel (GSBD) and wheat germ biodiesel (WGBD). Maximum heat release rate as observed for diesel, CBD, GSBD and WGBD are 63.2 J/°CA 60.7 J/°CA and 59 J/°CA and 43.4 J/°CA respectively. The brake-specific NO emission at full load is higher for CBD followed by GSBD, WGBD and diesel having values of 9.23 g/kWh, 8.91 g/kWh, 8.21 g/kWh and 7.6 g/kWh respectively. Conversely, the smoke emission is lower for CBD compared to the other tested fuels.
Afficher plus [+] Moins [-]Experimental study on NOx reduction in a grapeseed oil biodiesel-fueled CI engine using nanoemulsions and SCR retrofitment
2020
Stringent emission norms impose challenges to original equipment manufacturer (OEM) in reducing diesel engine emissions. Implementing renewable fuels as alternative energy sources in diesel engines leads to increased emission levels particularly NOₓ. In this work, performance, combustion, and emission parameters from a diesel engine powered with grapeseed oil biodiesel (GSBD) was investigated. Nano additive emulsions of cerium oxide (CeO₂) and zinc oxide (ZnO) at 100 ppm each were added to grapeseed oil biodiesel. To enhance the NOₓ reduction task further, an advanced technology called selective catalytic reduction (SCR) system was used. With easy availability of aqueous urea, careful injection, and distribution of the reductant solution, a paradigm change was brought about in NOₓ reduction technology. The experiments were carried out with and without SCR for better understanding and investigation. The percentage reduction of NOₓ emission by adding cerium oxide and zinc oxide emulsion blends were 4.19% and 13.13%, respectively. The overall reduction in NOₓ emission were 74.16% and 80.06% with SCR for cerium oxide and zinc oxide emulsion blends. The research conclusions make grapeseed oil biodiesel conceivable as an effective alternate fuel for diesel engines without any engine modifications.
Afficher plus [+] Moins [-]Synthesis of rigid polyurethane foams from phosphorylated biopolyols
2019
de Haro, Juan Carlos | López-Pedrajas, Daniel | Pérez, Angel | Rodríguez, Juan Francisco | Carmona Rodríguez, Manuel
Renewable resources are playing a key role on the synthesis of biodegradable polyols. Moreover, the incorporation of covalently linked additives is increasing in importance in the polyurethane (PU) market. In this work, previously epoxidized grape seed oil and methyl oleate were transformed into phosphorylated biopolyols through an acid-catalyzed ring-opening hydrolysis in the presence of H₃PO₄. The formation of phosphate polyesters was confirmed by FT-IR and ³¹P-NMR. However, the synthesis of a high-quality PU rigid foam was not possible using exclusively these polyols attending to their low hydroxyl value. In that way, different rigid PU foams were prepared from the phosphorylated biopolyols and the commercial polyol Alcupol R4520. It was observed that phosphorylated biopolyols can be incorporated up to a 57 wt.% in the PU synthesis without significant structural changes with respect to the commercial foam. Finally, thermogravimetric and EDAX analyses revealed an improvement of thermal stability by the formation of a protective phosphorocarbonaceous char layer.
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