Semi-continuous biomass gasification with water under sub critical conditions

• Published in: Fuel (Guildford) 2013-10, Vol.112, p.249-253
• Main Authors: Molino, A., Migliori, M., Nanna, F., Tarquini, P., Braccio, G.
• Format: Article
• Language: English
• Subjects: Almond shell; Applied sciences; Biomass; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fuels; Gasification; Natural energy; Prunus dulcis; Subcritical conditions; Water
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2013.05.020

•Results of the gasification process with water in near critical point.•Sodium oxide effect was evaluated in order to establish its effect on the products.•Hydrothermal process of biomass and wastes.•Possible to obtain a liquid phase that includes some precursor of different products. The paper reports on gasification of almond shells with water at high pressure (above critical value) and temperature. The experimental set up was a semi-continuous reactor, an innovative configuration allowing to continuously remove the gas product from the reaction vessel. The adoption of pressure conditions well above water critical value (30MPa) and relatively low temperature (300°C) confirmed suitable reaction pathways for biomass conversion with high efficiency leading to a liquid phase rich of some interesting compounds (HMF, furfural). In order to increase the process performances, sodium hydroxide was added as promoter of the gasification reactions. According to an already proposed reaction scheme, results confirmed a positive impact of the additional compound to the liquid yield and quality, while the gaseous phase was enriched in carbon dioxide.