Torrefaction of Willow in Batch Reactor and Co-Firing of Torrefied Willow with Coal

Hilal Unyay (), Piotr Piersa, Magdalena Zabochnicka, Zdzisława Romanowska-Duda, Piotr Kuryło, Ksawery Kuligowski, Paweł Kazimierski, Taras Hutsol, Arkadiusz Dyjakon, Edyta Wrzesińska-Jędrusiak, Andrzej Obraniak and Szymon Szufa ()
Additional contact information
Hilal Unyay: Faculty of Process and Environmental Engineering, Lodz University of Technology, Wolczanska 213, 90-924 Lodz, Poland
Piotr Piersa: Faculty of Process and Environmental Engineering, Lodz University of Technology, Wolczanska 213, 90-924 Lodz, Poland
Magdalena Zabochnicka: Faculty of Infrastructure and Environment, Czestochowa University of Technology, Dabrowskiego 69, 42-201 Czestochowa, Poland
Zdzisława Romanowska-Duda: Faculty of Biology and Environmental Protection, University of Lodz, Banacha Str. 12/16, 92-237 Lodz, Poland
Piotr Kuryło: Faculty of Mechanical Engineering, University of Zielona Góra, 65-516 Zielona Gora, Poland
Ksawery Kuligowski: Physical Aspects of Ecoenergy Department, The Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14 Str., 80-231 Gdansk, Poland
Paweł Kazimierski: The Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-231 Gdansk, Poland
Taras Hutsol: Department of Mechanics and Agroecosystems Engineering, Polissia National University, Staryi Blvd 7, 10008 Zhytomyr, Ukraine
Arkadiusz Dyjakon: Department of Applied Bioeconomy, Wroclaw University of Environmental and Life Sciences, Chelmonskiego 37a, 51-630 Wroclaw, Poland
Edyta Wrzesińska-Jędrusiak: Department of Technologies, Institute of Technology and Life Sciences—National Research Institute, Hrabska Avenue 3, Falenty, 05-090 Raszyn, Poland
Andrzej Obraniak: Faculty of Process and Environmental Engineering, Lodz University of Technology, Wolczanska 213, 90-924 Lodz, Poland
Szymon Szufa: Faculty of Process and Environmental Engineering, Lodz University of Technology, Wolczanska 213, 90-924 Lodz, Poland

Energies, 2023, vol. 16, issue 24, 1-23

Abstract: The torrefaction process represents a thermal conversion technique conducted at relatively low temperatures ranging between 200 to 300 °C. Its objective is to produce fuel with a higher energy density by decomposing the reactive portion of hemicellulose. In this study, the kinetics of mass loss during torrefaction were investigated for willow. The experiments were carried out under isothermal conditions using thermogravimetric analysis. Batch torrefaction reactor designs were conducted and explained in detail. Co-combustion of willow with hard coal (origin: Katowice mine) in different mass ratios (25% biomass + 75% coal, 50% biomass + 50% coal, and 75% biomass + 25% coal) was conducted in addition to raw biomass torrefaction. TG/MS analysis (a combination of thermogravimetric analysis with mass spectrometry analysis) was performed in the research. The optimal torrefaction conditions for willow were identified as an average temperature of 245 °C and a residence time of 14 min, resulting in the lowest mass loss (30.15%). However, it was noted that the composition of torgas, a by-product of torrefaction, presents challenges in providing a combustible gas with sufficient heat flux to meet the energy needs of the process. Prolonged residence times over 15 min and higher average temperatures above 250 °C lead to excessive energy losses from volatile torrefaction products, making them suboptimal for willow. On the other hand, the co-combustion of torrefied biomass with hard coal offers advantages in reduced sulfur emissions but can lead to increased NOx emissions when biomass with a higher nitrogen content is co-combusted in proportions exceeding 50% biomass. This paper summarizes findings related to optimizing torrefaction conditions, challenges in torgas composition, and the emissions implications of co-combustion.

Keywords: torrefaction; co-torrefaction; biochar; reactor design; TGA-FTIR; TG/MS (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2023
References: View references in EconPapers View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/1996-1073/16/24/8083/pdf (application/pdf)
https://www.mdpi.com/1996-1073/16/24/8083/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:16:y:2023:i:24:p:8083-:d:1301117

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().