Application of Life Cycle Sustainability Assessment to Used Lubricant Oil Management in South Brazilian Region

Used Lubricant Oil (ULO) is a hazardous waste resulting from lubricant oil used in motorized equipment to reduce friction between moving surfaces that, over time, wear outs and becomes contaminated. The purpose of this study is to compare the sustainability of two ULO management systems in Brazil: one designated in this study by the TTR scenario (which includes transportation, trans-shipment, and re-refining phases), the other designated by the TsTR scenario (without the trans-shipment phase) to evaluate which scenario is socially, economically, and environmentally more efficient. The study uses the life cycle sustainability assessment (LCSA) methodology. As a combination of life cycle assessment (LCA), life cycle cost (LCC), and social life cycle assessment (s-LCA), it integrates the three sustainability dimensions (environmental, social, and economic). The sustainability index was calculated by aggregating data from eight environmental indicators, five economic indicators, and five social indicators. The results showed that the TsTR scenario presented the best values for the sustainability assessment than the TTR scenario. The TsTR scenario had the best social and economic performance, and the TTR scenario had the best environmental performance. The differences observed in those scenarios’ performances were noted by the absence or presence of the trans-shipment center. The absence of this center improved the social and economic performance of the scenario. The social dimension was improved by the elimination of the stage that causes problems related to social and economic dimensions by reducing several costs that can be associated with it. The presence of the trans-shipment center improves the environmental performance scenario by reducing the number of hazards that could impact the re-refining phase. The LCSA methodology enables a comparative life cycle assessment of two alternative system evaluations of ULO management by the sustainability index of each scenario. This index helps to analyze the contributions of each of the 18 categories and subcategories in the perspective of the sustainability dimensions and, consequently, to carry out their integrated evaluation, aiming to define the best sustainability scenario