Towards Higher Quality of Recycled Plastics: Limitations from the Material’s Perspective

Abstract

The increasing consumption of plastics and plastic products results in correspondingly substantial volumes of waste, which poses considerable environmental burdens. With the ongoing environmental actions, the application of circular economy on this waste stream is becoming inevitable. In this paper, the topics of plastics recycling, circular economy on plastics, and challenges to plastic waste recycling are critically reviewed. In the first part of this paper, the development of research on plastic recycling was viewed from 1950 until 2020 using the scientific database Web of Science, and 682 related studies were found and used to assess the changing research priorities along that timeline. The following sections discuss the potentials and requirements to enhance the quality of the produced recycled plastic, in connection with the factors that currently limit it. In conclusion, the quality of recycled plastic is generally determined by the homogeneity of the recovered plastic feed. There are various strategies which could be implemented to overcome the hindrances identified in the paper and to improve the quality of the recycled plastic, such as working on enhanced product designs for minimised waste heterogeneity and controlling the materials’ degree of contamination by applying advanced sorting.

Overview on the Key Figures with Impact on the Circular Economy Through the Life Cycle of Plastics

“…Actually, "plastic waste management is at a dismal level, especially in developing countries and so, there is need to develop clear mechanisms to address plastic issues for better monitoring, innovations, technology transfer and collaboration between organizations and citizen science to take collective action" [9]. On the other side, "the increasing consumption of plastics and plastic products results in correspondingly substantial volumes of waste, but with the ongoing environmental actions, the application of circular economy on the waste stream is becoming inevitable" [10].…”

Studies on the Possibilities of Improving Plastic Management Services

“…Taking into consideration that the consumption per citizen is constantly increasing, the necessity of developing some population awareness campaigns regarding the environmental benefits brought by the selective collection of waste is imperative [5][6][7][8]. Plastic waste, produced mainly out of products of petroleum processing, that is from non-renewable resources, is perceived as valuable from the point of view of material recovery [5][6][7][8][9].…”

“…Generally, recycling is the most used solution for solving plastic waste problems [5][6][7][8][9]. However, when recycling is not the most feasible solution due to its high thermal power, plastic waste is seen as a potential alternative energy source of interest [5][6][7][8][9].…”

“…After adhering to the European Union (EU), Romania had to adapt its legal regulations to EU standards, including those of environmental policy. The need to implement these standards, among others, the Directive of Packaging and Waste Packaging [10], to the Romanian law, has increased the awareness of decision-makers in Romania regarding the issue of planning and adequate development of waste management systems [9].…”

“…The recovery of material and energy from waste is seen as feasible solutions to the problem of the increasing amounts of waste, also perceived as a step towards sustainable development in modern societies [9].…”