Optimizing bone and biomass co-torrefaction parameters: High-performance arsenic removal from wastewater via co-torrefied bone char

Wei-Hsin Chen; Partha Pratim Biswas; Eilhann E Kwon; Kun-Yi Andrew Lin; Saravanan Rajendran; Jo-Shu Chang

doi:10.1016/j.envres.2024.118990

Optimizing bone and biomass co-torrefaction parameters: High-performance arsenic removal from wastewater via co-torrefied bone char

Environ Res. 2024 Apr 24;252(Pt 3):118990. doi: 10.1016/j.envres.2024.118990. Online ahead of print.

Authors

Wei-Hsin Chen¹, Partha Pratim Biswas², Eilhann E Kwon³, Kun-Yi Andrew Lin⁴, Saravanan Rajendran⁵, Jo-Shu Chang⁶

Affiliations

¹ Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan, 701, Taiwan; Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, 407, Taiwan; Department of Mechanical Engineering, National Chin-Yi University of Technology, Taichung, 411, Taiwan. Electronic address: weihsinchen@gmail.com.
² Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, 407, Taiwan; College of Engineering, Tunghai University, Taichung, 407, Taiwan. Electronic address: myfreedom2013sky@gmail.com.
³ Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul, 04763, Republic of Korea.
⁴ Department of Environmental Engineering & Innovation and Development Center of Sustainable Agriculture, National Chung Hsing University, Taichung, Taiwan; Institute of Analytical and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan.
⁵ Instituto de Alta Investigación, Universidad de Tarapacá, Arica, 1000000, Chile.
⁶ Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung, 407, Taiwan; Department of Chemical and Materials Engineering, Tunghai University, Taiwan; Department of Chemical Engineering, National Cheng Kung University, Taiwan.

PMID: 38670214
DOI: 10.1016/j.envres.2024.118990

Abstract

This study aimed to investigate bone char's physicochemical transformations through co-torrefaction and co-pyrolysis processes with biomass. Additionally, it aimed to analyze the carbon sequestration process during co-torrefaction of bone and biomass and optimize the process parameters of co-torrefaction. Finally, the study sought to evaluate the arsenic sorption capacity of both torrefied and co-torrefied bone char. Bone and biomass co-torrefaction was conducted at 175 °C-300 °C. An orthogonal array of Taguchi techniques and artificial neural networks (ANN) were employed to investigate the influence of various torrefaction parameters on carbon dioxide sequestration within torrefied bone char. A co-torrefied bone char, torrefied at a reaction temperature of 300 °C, a heating rate of 15 °C·min^-1, and mixed with 5 g m of biomass (wood dust), was selected for the arsenic (III) sorption experiment due to its elevated carbonate content. The results revealed a higher carbonate fraction (21%) in co-torrefied bone char at 300 °C compared to co-pyrolyzed bone char (500-700 °C). Taguchi and artificial neural network (ANN) analyses indicated that the relative impact of process factors on carbonate substitution in bone char followed the order of co-torrefaction temperature (38.8%) > heating rate (31.06%) > addition of wood biomass (30.1%). Co-torrefied bone chars at 300 °C exhibited a sorption capacity of approximately 3 mg g^-1, surpassing values observed for pyrolyzed bone chars at 900 °C in the literature. The findings suggest that co-torrefied bone char could serve effectively as a sorbent in filters for wastewater treatment and potentially fulfill roles such as a remediation agent, pH stabilizer, or valuable source of biofertilizer in agricultural applications.

Keywords: Arsenic sorption mechanism; Carbon dioxide sequestration; Co-torrefied bone char; Energy-efficient absorbent; Optimization; Wastewater treatment.