Estabilidade de blendas de diesel e biodiesel em condições distintas de temperatura e umidade

• Ano de defesa: 2018
• Autor(a) principal: Bruna Elói do Amaral
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Envelhecimento acelerado; Condições climáticas; Armazenamento; Degradação; Biodiesel; Envelhecimento natural; Engenharia quimica; Biodiesel Armazenamento
• Link de acesso: http://hdl.handle.net/1843/BUOS-B8UF3B

Diesel/biodiesel blends have great relevance in the market, since they cover needs involving both the economic and environmental sectors. However, the biodiesel introduction in the fuel matrix has led to product stability problems. Such issues depend on blends composition, storage time and conditions. The objective of this work is to evaluate the stability of diesel blends with biodiesels produced from soybeans and from tallow and soybeans, under different storage conditions, at the levels B5, B10, B15, and B20. For this, the samples natural aging was carried out over six months. They were stored in two reservoirs, one kept in normal climatic conditions for Belo Horizonte MG, and the other with high humidity, in order to simulate fuel storage in Amazon region. The stability evaluation was performed monthly, through analysis of physical-chemical properties of the samples, correlating them with the quality standards required by the Brazilian legislation. The results show that blends with higher biodiesel content presented more nonconformities. A reduction in fuel quality could occur in short-term, even for those with antioxidant additives. No significant variations were observed regarding the type of raw material used in biodiesel production. However, it was observed that climatic characteristics have an effective performance in fuel quality, with transport and storage conditions being crucial for the commercialization of a product according to legally required standards. In addition, some parameters contemplated by the legislations should be revised, to suit the reality of fuel degradation processes. Additionally, a comparison between Rancimat accelerated aging method and the natural method was carried out. In this evaluation, similarities were observed between the degradation processes that occurred over time in the different aging methods adopted, but it was not possible to correlate the times of accelerated and natural aging. In general, the study demonstrates the problem generated by the addition of biodiesel to diesel, which can affect different levels of the fuels commercialization chain. Thus, the biofuel should be used in a judicious way, seeking viable alternatives that bypass the problems associated with its use