TY - JOUR
T1 - Dry and Hydrothermal Co-Carbonization of Mixed Refuse-Derived Fuel (RDF) for Solid Fuel Production
AU - Longo, Andrei
AU - Alves, Octávio
AU - Sen, Ali Umut
AU - Nobre, Catarina
AU - Brito, Paulo
AU - Gonçalves, Margarida
N1 - Funding Information:
The present work was funded by the Fundação para a Ciência e Tecnologia, I.P. (Portuguese Foundation for Science and Technology), by the project (UIDB/04077/2020-2023 and UIDP/04077/2020-2023) of Mechanical Engineering and Resource Sustainability Center—MEtRICs, by the project UIDB/00239/2020 of Forest Research Centre—CEF, by the project UIDB/05064/2020 (VALORIZA—Research Centre for Endogenous Resource Valorization), and by the Regional Operational Program of Alentejo (Alentejo2020) under Portugal 2020 (Operational Program for Competitiveness and Internationalization), grant no. ALT20-05-3559-FSE-000035.
Publisher Copyright:
© 2024 by the authors.
PY - 2024/1/16
Y1 - 2024/1/16
N2 - The present study aims to test several conditions of the thermochemical pretreatment of torrefaction and carbonization to improve the physical and combustible properties of the Portuguese RDF. Therefore, two different types of RDF were submitted alone or mixed in 25%, 50%, and 75% proportions to dry carbonization processes in a range of temperatures between 250 to 350 °C and residence time between 15 and 60 min. Hydrothermal carbonization was also carried out with RDF samples and their 50% mixture at temperatures of 250 and 300 °C for 30 min. The properties of the 51 chars and hydrochars produced were analyzed. Mass yield, apparent density, proximate and elemental analysis, ash mineral composition, and higher heating value (HHV), among others, were determined to evaluate the combustion behavior improvement of the chars. The results show that after carbonization, the homogeneity and apparent density of the chars were increased compared to the raw RDF wastes. The chars and hydrochars produced present higher HHV and lower moisture and chlorine content. In the case of chars, a washing step seems to be essential to reduce the chlorine content to allow them to be used as an alternative fuel. In conclusion, both dry and wet carbonization demonstrated to be important pretreatments of the RDF to produce chars with improved physical and combustion properties.
AB - The present study aims to test several conditions of the thermochemical pretreatment of torrefaction and carbonization to improve the physical and combustible properties of the Portuguese RDF. Therefore, two different types of RDF were submitted alone or mixed in 25%, 50%, and 75% proportions to dry carbonization processes in a range of temperatures between 250 to 350 °C and residence time between 15 and 60 min. Hydrothermal carbonization was also carried out with RDF samples and their 50% mixture at temperatures of 250 and 300 °C for 30 min. The properties of the 51 chars and hydrochars produced were analyzed. Mass yield, apparent density, proximate and elemental analysis, ash mineral composition, and higher heating value (HHV), among others, were determined to evaluate the combustion behavior improvement of the chars. The results show that after carbonization, the homogeneity and apparent density of the chars were increased compared to the raw RDF wastes. The chars and hydrochars produced present higher HHV and lower moisture and chlorine content. In the case of chars, a washing step seems to be essential to reduce the chlorine content to allow them to be used as an alternative fuel. In conclusion, both dry and wet carbonization demonstrated to be important pretreatments of the RDF to produce chars with improved physical and combustion properties.
KW - carbonization
KW - lignocellulosic wastes
KW - polymeric wastes
KW - RDF
KW - waste valorization
UR - http://www.scopus.com/inward/record.url?scp=85188955096&partnerID=8YFLogxK
U2 - 10.3390/reactions5010003
DO - 10.3390/reactions5010003
M3 - Article
AN - SCOPUS:85188955096
SN - 2624-781X
VL - 5
SP - 77
EP - 97
JO - Reactions
JF - Reactions
IS - 1
ER -