Developing a sustainability-oriented multi-criteria game theoretical decision analysis framework: A case study of sludge management

Decision-making process can be influenced by many factors, including the interests and preferences of stakeholders, their interactions, as well as the considered criteria. This study constructs a methodology framework based on game theory and multi-criteria decision making (MCDM) approach to address the decision-making problem with conflicting interests of different parties for sustainable sludge management. The proposed framework compares the overall sustainability performances of the alternatives for the corresponding stakeholder based on the life cycle sustainability impacts and the weight of each criterion. The weights of considered criteria are determined by the opinions of different groups of stakeholders. Then, game theory is applied to assist the stakeholders share the costs and benefits and guide them to reach a consensus on the final selection for the sludge management technology. A case study applying the proposed framework to analyze the game between sludge treatment facility and the government was carried out. Four different sludge valorization technologies were selected as the alternative strategies for both players, including incineration for electricity production followed by landfill (S1), incineration for power generation followed by cement production (S2), biogas from sludge digestion for electricity generation by fuel cells (S3) and biogas from sludge digestion for electricity generation by combustion (S4). Results show that both the sludge treatment facility and the government may mutually benefit from S3 if the sludge treatment facility pays a tipping fee of $0.19–7.59 per kWh net electricity generation. Sensitivity analysis was also carried out to study the influence of weighting variations and parameter uncertainty on the final strategy selection and results revealed the stability of the proposed framework. The outcome of the framework can contribute to the sustainable decision-making process for the involved players and reach an agreement more efficiently.