Exploring the low-carbon development model for a hazardous waste treatment park from a life cycle assessment perspective

Abstract

China is actively committed to mitigating carbon emissions through its “Dual Carbon” and “Zero-Waste Cities” strategies. Hazardous waste (HW) treatment, a significant source of greenhouse gas (GHG) emissions, plays a crucial role in achieving carbon reduction targets. This study systematically assessed the carbon emissions and low-carbon pathways of a representative multi-HW treatment park in Qingdao using life cycle assessment and life cycle cost methodologies. In 2020, the total net GHG emissions of the HW park were 49,669.3 t CO₂-eq, with an average emission intensity of 1181.1 kg CO₂-eq per tonne of HW. Among the various treatment systems, medical waste (MW) incineration exhibited the highest GHG emission intensity (1377.6 kg CO₂-eq/t MW), followed by industrial hazardous waste (IHW) incineration (1076.4 kg CO₂-eq/t IHW), fly ash/slag treatment (9.7 kg CO₂-eq/t HW), and physicochemical treatment (8.5 kg CO₂-eq/t HW). Three integrated low-carbon pathways demonstrated that utilizing waste heat for heating exhibited the highest carbon mitigation potential, achieving up to −403.6 kg CO₂-eq/t IHW, followed by technological improvement and resource recycling. The combined low-carbon scenario could achieve a 49.5% reduction in total carbon emissions compared to the baseline scenario. Furthermore, economic performance improved, with treatment benefits increasing from 3431.3 RMB/t IHW to 3948.5 RMB/t IHW due to enhanced energy efficiency and resource recovery. This study provides a framework for assessing multi-HW parks’ carbon footprints and offers strategic insights for low-carbon, resource-efficient waste management. The findings also support sustainable multi-HW management and contribute to climate and decarbonization efforts.