An investigation of the Turkish forest products industry in terms of circular economy

Growing environmental concerns, resource constraints, and sustainability imperatives have made effective waste management and circular-economy practices a priority in the forest products industry. This thesis examines circularity opportunities and the potential for carbon-emission mitigation in Turkish forest products sector. The study comprises three parts. First, qualitative interviews were conducted with nine large-scale firms and analysed using thematic analysis; the findings indicate that residues are predominantly directed to low value-added uses, while high-quality recycling and industrial symbiosis remain limited. Second, product carbon footprints were quantified for six facilities (sawmill, pellet, furniture, particleboard, door, and waste-processing) under the ISO 14067:2018 framework and IPCC 2006 Tier 1 methodology. Unit-level results show the highest emissions for furniture and door manufacturing (1.57 kg CO₂e/kg ve 2.84 kg CO₂e/kg), and the lowest for pellet production (0.132 kg CO₂e/kg.). Third, a multi-objective mathematical optimisation model was developed to minimise the carbon footprint while maximising time-in-use in the circular utilisation of wood-based residues among these facilities. Model results were tested and interpreted by giving different weights to the objective functions. The study concludes by recommending that the cyclical use of wood-based waste across facilities be encouraged to reduce emissions and extend product lifespans, reflecting the duration of product lifespan within the carbon sink, in line with sustainability and environmental principles. Therefore, it is crucial for policymakers and industry representatives to develop decision-making processes based on multi-objective optimization and incentive mechanisms that prioritize fraction-process compatibility.