This paper presents a multi-objective optimization approach for biogas supply chains based on a superstructure to satisfy the biogas and biofertilizer demands in a geographical region at the maximum profit and the minimum environmental impact. This approach accounts for the optimal location for processing and purification technologies used to produce the biogas and biofertilizer as well as to determinate if a technology should be installed or not. Two case studies were solved for a geographical region in Mexico to show the applicability of the proposed methodology. One is the sale of purified biogas exclusively and the other one involves the sale of both non-purified and purified biogas. The results show that the implementation of the proposed optimization methodology yields significant economic and environmental benefits due to the simultaneous increase in the total annual profit and greenhouse gas emission savings. (C) 2019 Elsevier Ltd. All rights reserved.