A bi-level optimized approach for promoting the mixed treatment of municipal sludge and food waste

Environ Sci Pollut Res Int. 2023 Mar;30(14):41120-41141. doi: 10.1007/s11356-022-24683-1. Epub 2023 Jan 11.

Abstract

The mixed treatment of municipal sludge and food waste can generate renewable energy, solve the environmental and economic challenges caused by this waste, and has attracted significant research attention. Using environmentally friendly anaerobic co-digestion of municipal sludge and food waste can improve the effects of anaerobic mono-digestion and produce more biogas. However, as the municipal sludge and food waste managers are different, balancing the interests of both managers is needed to encourage anaerobic co-digestion development. By fully considering the interests of the local authority, the waste water treatment plants, and the food waste anaerobic digestion treatment plants, this paper developed a bi-level optimization approach based on Stackelberg equilibrium theory to resolve the conflicts between the different stakeholders, in which uncertain parameters were used to describe the uncertainties. The proposed model was then applied to a real case in Chongqing, China, to test its practicality, and scenario analyses under different policy parameter values were conducted to provide guidance for local authorities, waste water treatment plants, and food waste treatment plants. The proposed approach was found to provide balanced strategies for all three stakeholders, increase the renewable energy output of municipal sludge and food waste treatment 14.2 times, and reduce carbon emissions by 50%, thereby protecting the environment and achieving a circular economy.

Keywords: Anaerobic co-digestion; Circular economy; Optimization model; Policy research; System decision; Waste treatment.

MeSH terms

  • Anaerobiosis
  • Biofuels / analysis
  • Bioreactors
  • Food
  • Methane / analysis
  • Refuse Disposal*
  • Sewage / analysis
  • Water Purification*

Substances

  • Sewage
  • Biofuels
  • Methane