Synergistic Benefits of Pollution Reduction and Carbon Mitigation from Converting Food Waste into Carbon Sources for Wastewater Treatment Plants
The resource utilization of food waste contributes to reducing environmental pollution, driving nutrient cycling and biomass energy development, and promoting the resource recycling industry, achieving a win-win outcome for environment and economy. This study evaluated the resource recovery performance and environmental impacts of producing carbon sources for wastewater treatment through hydrolysis and acidification of food waste, comparing with two conventional alternatives: anaerobic fermentation and incineration. Results showed that among the three technologies, hydrolysis for carbon source production ranked middle in resource recycling efficiency, but its environmental benefits were superior to incineration and anaerobic fermentation. The hydrolysis process did not produce additional wastewater requiring treatment, and its greenhouse gas emissions and solid waste generation intensity were relatively low, at -40.7 kg CO2-eq/t and 9.3%, respectively. Carbon sources derived from food waste can replace commercial alternatives, reducing wastewater treatment costs and promoting synergies between pollution reduction and carbon mitigation. Sensitivity analysis revealed that water content in food waste significantly influences solid impurity generation and energy recovery efficiency of hydrolysis technology. In regions with high food waste generation and carbon source demand, hydrolysis technology is recommended to facilitate large-scale synergistic treatment of wastewater and food waste.