A parametric study of particle size influence on sewage sludge-derived hydrochar and coal char co-gasification: Reactivity and carbon conversion analysis
Azhar Ali Laghari , Asma Leghari , Akash Kumar , Lata Kumari , Muhammad Rizwan , Qurat-ul-ain Abro , Memon Kashif Ali , Yongheng Shen , Qingxia Guo
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引用次数: 0
Abstract
Sewage sludge (SS) poses significant environmental and socio-economic challenges due to its high moisture content and limited disposal options. Hydrothermal carbonization (HTC) has been identified as an effective pretreatment method to enhance the stability and reactivity of hydrochar (HC) for energy applications. This study investigates the co-gasification behavior of pyrolyzed HC derived from SS and coal char in CO2 environments, with a focus on the influence of temperature (850 °C, 900 °C, and 950 °C) and particle size (35 μm, 110 μm, 250 μm, and 430 μm) on gasification reactivity and carbon conversion. Experimental results show that smaller particles (35 μm) exhibited the highest reactivity due to their larger surface area-to-volume ratio, achieving a gasification rate of 0.010945 s⁻1 at 950 °C. Increasing the temperature significantly enhanced carbon conversion, with conversion rates accelerating particularly at 950 °C during the initial phases. Coal char demonstrated rapid thermal degradation, while HC displayed superior thermal stability and reduced reactivity at higher temperatures due to its more condensed carbon structure. Notably, HC concentrations (15 %) improved overall reactivity compared to lower concentrations (5 %), emphasizing the synergistic effects of co-gasification. This study highlights the critical role of temperature and particle size in optimizing waste-to-energy conversion processes, offering actionable insights for enhancing efficiency and sustainability in waste management systems.
期刊介绍:
Biomass & Bioenergy is an international journal publishing original research papers and short communications, review articles and case studies on biological resources, chemical and biological processes, and biomass products for new renewable sources of energy and materials.
The scope of the journal extends to the environmental, management and economic aspects of biomass and bioenergy.
Key areas covered by the journal:
• Biomass: sources, energy crop production processes, genetic improvements, composition. Please note that research on these biomass subjects must be linked directly to bioenergy generation.
• Biological Residues: residues/rests from agricultural production, forestry and plantations (palm, sugar etc), processing industries, and municipal sources (MSW). Papers on the use of biomass residues through innovative processes/technological novelty and/or consideration of feedstock/system sustainability (or unsustainability) are welcomed. However waste treatment processes and pollution control or mitigation which are only tangentially related to bioenergy are not in the scope of the journal, as they are more suited to publications in the environmental arena. Papers that describe conventional waste streams (ie well described in existing literature) that do not empirically address ''new'' added value from the process are not suitable for submission to the journal.
• Bioenergy Processes: fermentations, thermochemical conversions, liquid and gaseous fuels, and petrochemical substitutes
• Bioenergy Utilization: direct combustion, gasification, electricity production, chemical processes, and by-product remediation
• Biomass and the Environment: carbon cycle, the net energy efficiency of bioenergy systems, assessment of sustainability, and biodiversity issues.