Integrating circular economy in food waste management: insights from Thailand's shopping mall and community.

This study introduces circular food waste management strategies that promote collaboration between large enterprises and community-based sectors. Thermal dehydration and anaerobic digestion were implemented as treatment technologies in a shopping mall and a local community, respectively. Thermally treated food waste from the shopping mall showed an average moisture content of 1.86% with 49.3% carbohydrates, 21.0% protein, 12.9% fat, 7.0% fiber, 8.7% ash, and a carbon-to-nitrogen (C/N) ratio of 10.4. This dried organic material can be directly used as a soil amendment or supplied to communities as a cosubstrate for anaerobic digestion to improve digestate quality. Community food waste, with a moisture content of 75.6% and a C/N ratio of 12, was anaerobically digested to produce a nutrient-rich digestate (nitrogen = 2.38%, phosphorus = 6.01%, potassium = 0.6%, and C/N ratio = 15.6) that meets Thailand's fertilizer standards. The generated biogas, containing 41.1% methane and 32.7% carbon dioxide, is suitable for use as cooking fuel. Thermal dehydration exhibited strong economic feasibility in the shopping mall (SROI = 1.34), whereas anaerobic digestion yielded moderate social returns under the current operational scale (SROI = 0.59). Integrating these two technologies establishes a circular business model that can be successfully scaled through government support in training, product certification, market development, export facilitation, and infrastructure investment. The findings provide practical insights into addressing food waste challenges in Thailand while strengthening public-private partnerships and advancing SDG12 in alignment with circular economy principles.