Solid biofuels production from agricultural residues and processing by-products by means of torrefaction treatment: the case of sunflower chain
AbstractThe high heterogeneity of some residual biomasses makes rather difficult their energy use. Their standardisation is going to be a key aspect to get good quality biofuels from those residues. Torrefaction is an interesting process to improve the physical and chemical properties of lignocellulosic biomasses and to achieve standardisation. In the present study torrefaction has been employed on residues and by-products deriving from sunflower production chain, in particular sunflower stalks, husks and oil press cake. The thermal behaviour of these materials has been studied at first by thermogravimetric analysis in order to identify torrefaction temperatures range. Afterwards, different residence time and torrefaction temperatures have been tested in a bench top torrefaction reactor. Analyses of raw and torrefied materials have been carried out to assess the influence of the treatment. As a consequence of torrefaction, the carbon and ash contents increase while the volatilisation range reduces making the material more stable and standardised. Mass yield, energy yield and energy densification reach values of about 60%, 80% and 1.33 for sunflower stalks and 64%, 85% and 1.33 for sunflower oil press cake respectively. As highlighted by the results, torrefaction is more interesting for sunflower stalks than oil cake and husks due to their different original characteristics. Untreated oil press cake and husks, in fact, already show a good high heating value and, for this reason, their torrefaction should be mild to avoid an excessive ash concentration. On the contrary, for sunflower stalks the treatment is more useful and could be more severe.
PlumX Metrics provide insights into the ways people interact with individual pieces of research output (articles, conference proceedings, book chapters, and many more) in the online environment. Examples include, when research is mentioned in the news or is tweeted about. Collectively known as PlumX Metrics, these metrics are divided into five categories to help make sense of the huge amounts of data involved and to enable analysis by comparing like with like.
Copyright (c) 2014 Daniele Duca, Giovanni Riva, Ester Foppa Pedretti, Giuseppe Toscano, Chiara Mengarelli, Giorgio Rossini
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.