Hydrothermal liquefaction of OCC screen rejects for bio-oil, biochar, and water recovery
A hydrothermal liquefaction (HTL) process converts OCC screen rejects into bio-oil, biochar, and recyclable water. Process parameter optimization (temperature, pressure, residence time) targets maximum bio-oil yield and quality for use as a drop-in transportation fuel or for power and heat generation. Biochar supports soil amendment and water treatment, while aqueous-phase treatment and testing (BOD, COD, pH) support safe disposal or reuse. Techno-economic analysis evaluates energy efficiency and integration potential.
Overview
This solution uses hydrothermal liquefaction (HTL) to convert OCC screen rejects into valuable products: bio-oil, biochar, and recovered water. By optimizing process parameters such as temperature, pressure, and residence time, the yield and quality of bio-oil are maximized, supporting use as a drop-in fuel for transportation or direct use in power and heat generation. The produced biochar provides economic value for applications such as soil amendment and water treatment. The approach reduces waste sent to landfill by improving resource utilization.
Technical specifications
- Hydrothermal liquefaction (HTL): Operates under moderate temperatures (250-350℃) and pressures (100-200 bar).
- Feedstock Composition: OCC screen rejects contain 40-60% water, 20-40% plastic, and 5-20% other materials.
- Product Analysis: Includes GC-MS, FTIR, NMR, SEM, and CHNS analysis to characterize bio-oil and biochar quality.
- Aqueous Phase Treatment: Uses biochar for treating the aqueous phase with tests like BOD, COD, and pH to support safe disposal or reuse.
- Techno-economic Analysis: Evaluates energy efficiency and economic viability for integration into existing facilities.
Technology readiness level
This technology is at TRL 9, indicating it is fully mature and has been validated in operational environments, ready for commercial deployment.
About Queen's University
Queen’s University is a comprehensive public research institution with a large student body and global alumni network based in Kingston, Ontario. For industry, it offers a research and technology park with wet/dry labs, shared core facilities, and collaboration models from sponsored research to contract testing. Clinical translation is enabled by integration with Kingston’s major hospital system, providing governed access to patients, clinicians, and health data. Talent pipelines are built through structured internship programs and project-based engagements. Research is backed by Canada’s Tri‑Council agencies and the Canada Foundation for Innovation, plus provincial and industry support, and a dedicated tech transfer office advances IP, licensing, and startups.
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