Studies of the Morphological Composition and the Possibility of Energy Recovery of Residues After Sorting Plastics and Metals

In view of the growing level of the selective collection of plastic waste, the implementation of the CE, as well as the search for alternative, cheap energy sources, the rational management of residues after the sorting of this waste is becoming increasingly important. The article presents the result of studies carried out at the turn of 2024/2025 in four voivodeships in Poland. The aim of the study was to determine the morphological composition of residues after sorting selectively collected plastics and metals. Knowledge of the detailed morphological composition of sorting residues allows for the assessment of the effectiveness of the sorting process and the suitability of these residues for energy recovery. Innovative studies have shown that about 80% of the weight of sorting residues consists of fractions suitable as components of RDF. Another new aspect of this study is a comparison of the results of studies on selected fuel properties of RDF produced from ballast after the sorting of plastics and metals and those of RDF derived from ballast after the sorting of mixed municipal waste. RDF from plastic sorting residues has almost twice the net calorific value, higher chlorine and zinc content, and lower ash and moisture content. The practical part of the article proposes technological solutions to meet the requirements set for these types of fuels by cement and CHP.