INVESTIGADORES
PEREDA Selva
congresos y reuniones científicas
Título:
Thermodynamic modeling of fast pyrolysis bio-oil by group contribution
Autor/es:
ILLE, YANNIK; F. A. SANCHEZ; DAHMEN, NICOLAUS; PEREDA, SELVA
Reunión:
Congreso; 10th World Congress of Chemical Engineering; 2017
Resumen:
Fast pyrolysis bio-oil oil is a promising alternative to fossil fuels and is currently entering the heating oil market. Moreover, it can be further processed to synthesis gas, from which synthetic fuels and chemicals can be obtained. In pyrolysis plants, particular interest is devoted to the production of a maximum liquid yield, as a high density carrier that can be processed towards valuable products. Furthermore, liquids are a preferred form to store and transport energy carriers. Fast pyrolysis is carried out in diverse types of reactor systems, in which biomass is rapidly heated up by means of a heat carrier, mostly sand, which is separated after reaction, re-heated and recycled back to the reactor. Commercial break-through is not achieved completely today. The most critical step towards further development is the condensation of pyrolysis vapors formed in the reactor. Rapid cooling is required to immediately quench chemical reactions in order to obtain a maximum yield of liquid products. The phase behavior of biomass derived mixtures is highly non-ideal due to the presence of association and solvation effects. The numerous oxygenated derived species belong to certain families of organic compounds (alcohols, carboxylic acids, esters, etc) thus these complex mixtures with hundreds of compounds can be described by a reduced number of functional groups. For this reason the use of a group contribution approach is a logical choice for thermodynamic modeling. The Group Contribution with Association Equation of State(GCA-EoS) is especially suited for this aim. It has already proved excellent predictive capacity to represent the phase behavior of complex mixtures containing natural products and biofuels. As part of this work, GCA-EoS will be extended to describe phase behavior of fast pyrolysis bio-oils. The thermodynamic characterization of the multicomponent mixture is not simple; however, it is known that the bio-oil is composed by: (1) volatile organic compounds (mainly hydroxyacetaldehyde, acetol, acetic acid, and methanol), (2) water, (3) monolignols (4) polar compounds with moderate volatility (furans), (4) anhydrosugars (mainly levoglucosan), (5) extractive-derived compounds, (6) heavy polar compounds (likely oligomers derived from cellulose and hemicellulose), (7) heavy nonpolar compounds (lignin oligomers), and (8) MeOH−toluene insoluble (char). In this work, we will discuss the extension of the model to the groups required to describe monolignols and anhydrosugars.