Sustainable energy generation: Assessing the potential of sewage sludge and polyethylene-based fuel for energy applications

Abstract

This study explored the potential of using sewage sludge (SS) and polyethylene (PE) waste as alternative fuels within a circular economy framework. SS, characterized by a high-water content and the presence of heavy metals, and PE, a byproduct of the automotive industry with a high calorific value, were pelletized and co-incinerated in a fluidized bed combustor. The primary objective of this study was to assess the energy recovery potential and environmental impact of these materials individually and in a 1:1 blend. Life cycle assessment (LCA) methodology was employed to evaluate the environmental footprint, focusing on pollutant emissions and energy consumption during incineration. The results indicated that the co-incineration of SS and PE significantly increased the low heating value of the fuel, enhancing its competitiveness as an energy source. However, this process also led to a notable increase in pollutant emissions, particularly NOx and SO₂. Despite these challenges, this study demonstrates the feasibility of developing a sustainable alternative fuel from SS and PE, contributing to waste reduction and energy recovery in line with circular economic principles.