Multi-objective optimization of an integrated biofuel and power production network from Municipal Solid Waste (MSW) for Latin America

Abstract

Despite significant advances in waste management, there are still many challenges that require special and immediate attention. Such as, for example, the existence of uncontrolled open dumps, low recovery rates of waste fractions, expensive and inefficient treatments, and the environmental impact. Therefore, in this work, a multi-objective optimization is proposed to determine the optimal operation policy that considers the energetic valorization of MSW for Latin America, specifically Argentina, Brazil, Colombia, and Mexico. The optimization formulation considers the analysis of four technologies: anaerobic digestion, incineration, gasification, and pyrolysis, and it was developed, including the technical, economic, and environmental dimensions. This work addresses an approach for defining the relationships between the operational policies and the design of MSW management considering the above technologies. The solution to the problem consists of maximizing profit and the net emissions avoided from the operation of the technologies simultaneously. In addition, to attack the multi-objective problem, the epsilon-constraint method was used to find the optimal solutions. In addition, a trade-off solution is selected to present the main results associated with the operational policy of each country and as well with each proposed technology. Minimum sizes for the profitability of each technology were obtained for each country, and it was determined that Colombian plants and incineration technology require the lowest MSW ton managed to obtain profits opposing Brazil plants and pyrolysis technology. The model showed flexibility with the objective correlation, concluding that the economic and environmental objective functions are not necessarily in opposition. The present model is a general model that can be applied to another country or group of countries, considering the exact specifications.