González-Arias, JudithSánchez, Marta ElenaMartínez, Elia JudithCovalski, Camila de AlmeidaAlonso-Simón, AnaGonzález, RubénCara-Jiménez, Jorge2018-02-192021-02-272018-01-192021-02-272020González-Arias, Judith; Sánchez, Marta Elena; Martínez, Elia Judith; Covalski, Camila; Alonso-Simón, Ana; González, Rubén; Cara-Jiménez, Jorge (2020). Hydrothermal carbonization of olive tree pruning as a sustainableway for improving biomass energy potential: Effect of reaction parameters on fuel properties. Processes. ISSN 2227-9717. 8:10, p. 1-20http://hdl.handle.net/10198/23376Hydrothermal carbonization (HTC) allows the conversion of organic waste into a solid product called hydrochar with improved fuel properties. Olive tree pruning biomass (OTP), a very abundant residue in Mediterranean countries, was treated by HTC to obtain a solid fuel similar to coal that could be used in co-combustion processes. Three different reaction temperatures (220, 250, and 280 °C) and reaction times (3, 6, and 9 h) were selected. The hydrochars obtained were extensively analyzed to study their behavior as fuel (i.e., ultimate, proximate, fiber and thermogravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), activation energy, and combustion performance). The concentrations of cellulose, hemicellulose, and lignin in the samples depict a clear and consistent trend with the chemical reactions carried out in this treatment. Regarding O/C and H/C ratios and HHV, the hydrochars generated at more severe conditions are similar to lignite coal, reaching values of HHV up to 29.6 MJ kg-1. The higher stability of the solid is reflected by the increase of the activation energy (≈60 kJ mol-1), and ignition temperatures close to 400 °C. With this, HTC is a proper thermal treatment for the management of raw OTP biomass and its further conversion into a solid biofuel.engBioconversionBioenergyBiofuelCombustionHydrocharHydrothermal carbonizationOlive tree pruning biomassjournal article10.3390/PR8101201