Thesis Format
Integrated Article
Degree
Master of Engineering Science
Program
Chemical and Biochemical Engineering
Collaborative Specialization
Environment and Sustainability
Supervisor
Klinghoffer, Naomi
Abstract
This work explores the effects of torrefaction on Canadian Residential Solid Waste (CRSW) as a pretreatment to enhance energy conversion from waste through thermochemical processes like pyrolysis and gasification. As waste generation increases globally, torrefaction presents an efficient method to improve energy density, reduce moisture content, and enhance calorific value. Studies on CRSW torrefied under different atmospheres (N₂, CO₂, and flue gas) reveal enhanced calorific values and significant energy densification, with CO₂ and flue gas serving as viable, cost-effective substitutes for nitrogen. Results also indicate that different waste fractions respond uniquely to torrefaction, with forest residues and wood wastes balancing high energy recovery and moderate densification, while lemon peels and paper cups show varied performance. This work highlights the need for optimized torrefaction temperature, waste stream selection, and torrefaction medium to maximize the energy potential of CRSW, offering sustainable waste management and energy solutions.
Summary for Lay Audience
This study explores the use of Canadian Residential Solid Waste (CRSW) as a feedstock for processes which operate at high temperatures (500–1000°C) and have the potential to convert waste into sustainable chemicals and fuels. However, the natural characteristics of municipal solid waste, like high moisture content, low energy content, and low combustibility challenges for efficient energy conversion.
Torrefaction is a mild pretreatment method that heats CRSW to 200–300°C under controlled conditions to prevent complete combustion. This process reduces moisture, increases energy content, and enhances the waste’s combustibility, making it more suitable for energy applications. Our study investigates the effect of torrefaction on CRSW, analyzing changes in material properties across various temperatures to identify optimal conditions for its energy recovery.
Additionally, we examine the use of CO₂ and flue gas as economical alternatives to nitrogen for the torrefaction medium. Results indicate that CO₂ and flue gas provide comparable efficiency, supporting their potential for cost-effective, large-scale torrefaction of CRSW. By exploring individual fractions of CRSW, such as paper, plastic, and food waste, this study provides insights into optimizing torrefaction parameters to improve the viability of waste-to-energy processes.
Recommended Citation
Salami, Fatemeh, "Torrefaction of Canadian Residential Solid Waste" (2024). Electronic Thesis and Dissertation Repository. 10682.
https://ir.lib.uwo.ca/etd/10682
Creative Commons License
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