Thermochemical Conversion of Organic Solid Waste and Resource Utilization

Dear Colleagues,

With the continuous acceleration of global urbanization and industrialization, the generation of organic solid waste is increasing rapidly. Organic solid waste originates from a wide range of sources, including agricultural and forestry residues, municipal sludge, food waste, livestock manure, and industrial organic residues. Traditional disposal methods such as landfilling and direct incineration not only occupy substantial land resources but also pose environmental risks including leachate leakage, high energy consumption, and greenhouse gas emissions. Organic solid waste possesses dual attributes of pollutants and resources: improper disposal can cause severe ecological damage and resource wastage, whereas rational conversion can render it a valuable source of renewable energy and carbon materials. In this context, thermal treatment and resource utilization of organic solid waste have become central issues in global environmental governance and the energy transition.

Thermochemical conversion technologies (including drying incineration, pyrolytic carbonization, pyrolysis gasification, hydrothermal carbonization, etc.) have evolved into one of the mainstream routes for organic solid waste disposal, owing to their short reaction times, compact facilities, and capability to recover energy and produce high‑value carbon materials. Organic solid waste contains abundant biomass energy that can be converted into high‑value energy products, such as electricity, heat, biomethane, and green methanol, through efficient thermal treatment and resource recovery technologies, thereby reducing reliance on fossil fuels and contributing to the mitigation of greenhouse gas emission. Moreover, the solid‑phase products through thermal conversion (e.g., biochar) have broad application potential in soil improvement, carbon sequestration, and the production of functional materials.

Currently, this field is at a critical stage in the transition from fundamental research to technological integration and engineering application, yet it still faces a series of core scientific challenges, including difficulties in regulating product distribution due to feedstock complexity; bottlenecks in improving the yield and quality of high‑value products; balancing process efficiency and energy consumption; insufficient understanding of reactor scale‑up principles; and the cascade utilization of energy in polygeneration systems. In recent years, emerging approaches such as catalytic upgrading, chemical looping conversion, microwave/plasma‑assisted heating, smoldering, and AI‑driven process optimization have provided new opportunities to overcome these bottlenecks.

This Special Issue, themed "Thermochemical Conversion and Resource Utilization of Organic Solid Waste," aims to gather cutting‑edge research covering the entire thermochemical conversion chain. Particular attention will be paid to reaction mechanisms and kinetics, novel catalytic materials and processes, targeted regulation of products and valorization pathways, process intensification, and system integration optimization. We cordially invite scholars from around the world to contribute original research articles and review insights, thereby advancing theoretical innovation and technological breakthroughs in this field, and contributing to the efficient resource utilization of organic solid waste.

Topics include, but are not limited to the following:

• Fundamental Thermodynamics and Reaction Kinetics of Thermochemical Conversion.
• Technologies and Process Optimization for Pyrolysis, Gasification, Combustion, and Related Methods.
• Novel Thermal Treatment Technologies and Processes.
• High‑Value Utilization of Thermochemical Conversion Products.
• Synergistic Thermochemical Conversion of Multi‑Source Organic Solid Wastes.
• Application of Artificial Intelligence and Data‑Driven Approaches in Thermochemical Conversion Processes.
• Techno‑Economic Assessment and Life Cycle Analysis of Thermochemical Conversion Systems.

We welcome original research articles, comprehensive reviews, and short communications that advance the fundamental understanding and technological innovation of thermochemical conversion for sustainable waste valorization. Contributions addressing the full spectrum of research topics—from reaction kinetics and novel thermal processes to AI‑driven optimization and life‑cycle sustainability assessment—are particularly encouraged. Interdisciplinary studies that bridge experimental investigation with multiscale modeling, or integrate process development with techno‑economic and environmental evaluation, will receive special consideration.

Thank you for your interest, and we hope you will consider contributing to this Special Issue.

Sincerely,

Dr. Lun Ma
Dr. Jingchun Huang
Dr. Qianshi Song
Guest Editors

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