Spatial disparity of life-cycle water use and greenhouse gas emissions from food waste resource conversion in China

Abstract

With the construction of “Zero-Waste” City and the goals of “carbon peaking and carbon neutrality”, the resource utilization of food waste (FW) could not only reduce waste treatment pressure but also be converted into the high-value-added products in China. However, the selection of FW resource utilization technologies in China still remains contentious, with a notable absence of the region-specific guidance that adequately addresses local conditions. This study innovatively constructed a hybrid life cycle assessment framework, incorporating a multi-regional input-output table, to systematically evaluate the impact of spatial disparity on the environmental performance of eight FW resource utilization technologies. Results indicated that spatial disparity have a significant impact on water use and greenhouse gas emissions. Total water use and greenhouse gas (GHG) emissions of eight FW conversion technologies across 30 provinces ranged from 0.8 to 13.2 m³ t⁻¹ and 72.6–573.0 kg CO2-eq t⁻¹, respectively. Additionally, decomposition analysis presented that the sector of electricity and heat production was the primary driver of disparities across 30 provinces, with coefficients of variation ranging from 17.2 %–55.1 % for water consumption and 5.2 %–25.0 % for GHG emissions. Meanwhile, the sensitivity of water use or GHG emissions to electricity exhibited the consistent fluctuating trends but with varying amplitudes. Moreover, due to spatial teleconnection, the highest inter-provincial embodied water use and GHG emissions mainly occurred in Jiangsu and Inner Mongolia, respectively. This study not only emphasizes the importance of spatial disparity on the environmental analysis but also provides a theoretical foundation for formulating regional resource management and emission reduction policies.