Evaluation of technological alternatives for the treatment of urban solid waste: A case study of Minas Gerais, Brazil

Given the problems faced with population growth and the constant increase in Municipal Solid Waste (MSW), there is a greater need for less impactful waste management alternatives. The region of study addressed in this work is Minas Gerais, the second most populous state in Brazil, where technological alternatives are evaluated for the treatment of Municipal Solid Waste from an energetic, economic and environmental point of view. Based on data from the literature, a characterization of the MSW produced in the state was carried out, and different energy recovery technologies were evaluated considering the biochemical and thermochemical routes. Different scenarios were created with the considered technologies in order to verify the best alternatives according to population size in the municipalities of Minas Gerais. After analyzing the technologies, their application was evaluated for municipalities grouped in consortia. To aid the development of the work, a methodology was proposed that can be applied in decision-making for MSW in other Brazilian states as well as any country in the world. The results show that the scenarios that use incineration and gasification in conjunction with anaerobic digestion and recycling allow reaching the highest potential for electricity generation. The viable scenarios from the economic point of view would allow for reaching 56.7% of the total potential for electricity generation existent in the state and a reduction of 34% of the maximum avoided emissions. Through the formation of municipal consortia, it is possible to reach 93.5% of the total electricity generation potential using technologies that are not economically viable in smaller population ranges size. The highest avoided emissions achieved using anaerobic digestion technologies in conjunction with recycling and the scenarios that combine incineration and gasification with anaerobic digestion and recycling. The results aimed to provide the reader with a guide for MSW management, taking into account the population size, the characteristics of the waste and the different technologies that can be used and associated with each other.