BUSCADOR RECOLECTA

This study investigates the suitability of different lignocellulosic sources, namely eucalyptus, apple bagasse, and out-of-use wood, for injection into blast furnaces (BFs). While wastes possess carbon potential, their high moisture renders them unsuitable for direct energy utilization. Additionally, the P and K impurities, particularly in apple bagasse, can pose operational and product quality challenges in BF. Thus, different thermochemical processes were performed to convert raw biomass into a more suitable carbon fuel. Low-temperature carbonization was selected for eucalyptus, yielding a biochar with properties closer to the low-rank coal. Hydrothermal carbonization was chosen for apple bagasse and out-of-use wood, resulting in hydrochars with enhanced fuel characteristics and fewer adverse inorganic species but still limiting the amount in binary PCI blends. Thermogravimetry evaluated the cause–effect relationships between coal and coal- and bio-based chars during co-pyrolysis, co-combustion and CO₂-gasification. No synergistic effects for char formation were observed, while biochars benefited ignition and reactivity during combustion at the programmed temperature. From heat-flow data in combustion, the high calorific values of the chars were well predicted. The CO₂-gasification profiles of in situ chars revealed that lignin-rich hydrochars exhibited higher reactivity and conversion than those with a higher carbohydrate content, making them more suitable for gasification applications., The authors wish to acknowledge the funding support from the European Union’s Horizon 2020 research and innovation program, under grant agreement No. 101006656 GICO Project, and The Spanish National Research Council (CSIC) through the project PIE-202380E010., Peer reviewed

The current urgent need for clean energy has sparked interest in hydrothermal carbonization (HTC) as a sustainable avenue to convert high moisture biomass wastes into an efficient bioenergy source. Without destructive methodologies and offering distinct advantages (e.g. real-time analysis) over traditional assessments, chemometric methods coupled to Fourier Transform Infrared Spectroscopy (FTIR) is presented as an innovative approach for a rapid assessment of the higher heating value (HHV) of hydrochars. With the help of advanced chemometric techniques such as Partial Least Squares (PLS) or Sequentially Orthogonalized PLS (SO-PLS) further insights are gained into the underlying chemical transformations during HTC treatment of a wide variety of biodegradable wastes. Our model predicts the HHV of the diverse hydrochars with an impressive R2 value of 0.961 and an RMSE of 0.845 MJ/kg. The scores and loading plots point out the pivotal functional groups that distinguish the various hydrochars, while also unveiling the inherent similarities among them. A second model has been further devised to predict the HHV of hydrochar as a function of feedstock composition and HTC operation conditions, thus allowing process optimization. This challenging approach can be extrapolated to quickly evaluate other physicochemical parameters of hydrochars designed for various applications., This project belongs to the European Union's Horizon 2020 research and innovation program, under grant agreement No. 101006656 GICO Project. Funding from Principado de Asturias and the ERDF (project IDI/2021/000037) is gratefully acknowledged. The supply of wastes by COGERSA, Sidra Fanjúl, Queseria La Borbolla, DACSA group and Consorcio EDER is highly appreciated., Peer reviewed