Assessing the environmental impact of waste management: a comparative study of CO2 emissions with a focus on recycling and incineration

In waste management, the assessment of CO₂ emissions offers the possibility to evaluate and compare the environmental impact of different waste treatment processes. Here, we compare the performance of waste incineration with alternative thermal treatment scenarios and recycling scenarios to the primary production of materials to analyze the respective CO₂ emissions. The aim is to determine whether thermal and material recycling of waste results in (net) CO₂ surpluses or reductions, thus, showing whether it makes sense for climate ambitions to recover waste, thermally or materially. A case study of an internationally active waste management company in Austria is analyzed, conducting a life cycle assessment of its thermal and material waste recycling. On thermal waste treatment the core of the analysis is the comparison with primary energy sources. Using waste as an energy source, especially in cement plants and the paper industry, has proven to be an effective technology for reducing CO₂ emissions. We also find current practices in material recycling to be of lower CO₂ emissions than alternative primary material supply. Scaling results to the national level we find that for the case of Austria current waste management practices have the potential to save an equivalent of 2.6% of Austria's total CO₂ emissions (all sectors) for thermal fractions and an equivalent of 1% for material recycling.