The Effect of Timing and Oxidation on Emissions from Biodiesel-Fueled Engines

Biodiesel de soja: taxa de conversão em ésteres etílicos, caracterização físico-química e consumo em gerador de energia

“…Entre essas alternativas, a transesterificação tem se apresentado como a melhor opção 2,12 , visto que o processo é relativamente simples 1 promovendo a obtenção de um combustível, denominado biodiesel, cujas propriedades são similares às do óleo diesel 3,8,9,13 . O biodiesel pode então ser definido como sendo um mono-alquil éster de ácidos graxos derivado de fontes renováveis, como óleos vegetais e gorduras animais 4,14,15 , obtido através de um processo de transesterificação, no qual ocorre a transformação de triglicerídeos em moléculas menores de ésteres de ácidos graxos 9,12 . Encontra-se registrado na "Environment Protection Agency -EPA -USA" como combustível e como aditivo para combustíveis e pode ser usado puro a 100% (B100), em mistura com o diesel de petróleo (B20), ou numa proporção baixa como aditivo de 1 a 5% 16 ; sua utilização está associada à substituição de combustíveis fósseis em motores do ciclo diesel 6,17 , sem haver a necessidade de nenhuma modificação no motor 18 .…”

Biodiesel effects on particulate radiocarbon (14C) emissions from a diesel engine

“…Biodiesel is believed to decrease CO and THC emissions because of the esterfied oxygen in the fuel, which increases the completeness of combustion. While some have attributed the increase in biodiesel NO x formation to higher combustion temperatures, Monyem et al (Monyem et al 2001) reported biodiesel flame temperatures lower than that of petrodiesel. Increased NO x observed with biodiesel could also be caused by fuel properties such as oxygen content and cetane number.…”

“…Increased NO x observed with biodiesel could also be caused by fuel properties such as oxygen content and cetane number. One theory states that more oxygen available in the reaction zone during combustion leads to a greater likelihood of NO x formation (Monyem et al 2001). Biodiesel has a roughly 10% higher oxygen content than typical diesel fuel (Pahl 2004); the exact difference depends on the feedstock and production process.…”

“…Biodiesel has a roughly 10% higher oxygen content than typical diesel fuel (Pahl 2004); the exact difference depends on the feedstock and production process. Combustion timing has proven to be more advanced for biodiesel than for diesel fuel due to its higher cetane number (Monyem et al 2001). …”

Improvement of Performance of Dual Fuel Engine Operated at Part Load

“…Researchers (Raheman and Ghadge, 2007;Puhan et al, 2005) have reported that the biodiesel derived from Mahua oil (MO) can be used as sole fuel or blends with diesel in diesel engines, with considerable reduction in CO, UBHC and smoke emissions and slightly higher NOx emission. From the literature (Monyem et al, 2001;Nwafor, 2005;Manieniyan and Sivaprakasam, 2008;Banapurmath et al, 2009;Sahoo et al, 2009), it is observed that injection timing is one of the variables which affect the performance and emissions of diesel engines. Hence in the present work, the injection timing was advanced and its effect on engine performance was studied.…”