Research on the Morphological Composition and Recovery Possibilities of Selectively Collected Plastics and Metals—A Case Study

Abstract

The basis for the assessment of the quality of selective waste collection, as well as the direction of modernization of municipal waste sorting technology, should be morphological composition studies. According to research, the gold standard for the assessment of the quality of selective waste collection, as well as the direction of modernization of municipal waste sorting technology, is morphological composition studies. Selective collection of municipal waste is an indispensable element of the waste management system, particularly important in terms of the increasing recycling levels obtained. The recycling of problematic and polluting plastics is one of the main challenges of the European circular economy. By problematic plastics, we mean those that are not suitable for recycling, or their recycling is difficult and expensive for technological reasons, resulting in problems with their management on the market. In 2022, the level of plastic recycling in Europe reached 26.9%. This article presents the results of studies on the morphological composition of selectively collected plastics and metals carried out in the summer and autumn of 2023 for a large city in Poland in the Silesian agglomeration. As a result, the quality of selectively collected waste, the share of pollutants in it, depending on the type of development, and the real possibilities of its recovery were determined. As part of the results obtained, a simulation was also carried out on how the deposit system planned from the first of October 2025 in Poland will affect the morphological composition of plastics and metals currently collected in the yellow container/bag.

1. Introduction

Selective collection of municipal waste is a major challenge in the third decade of the 21st century. The shrinking of natural resources is causing us to turn to recycled materials. A good example here is the selective collection of plastics in the yellow bag and yellow bin system. It is intended to be a material that is recycled and reintroduced to the market. Of course, all processes must comply with the principles of recycling and the Circular Economy [1]. Those principles depend on the region of the world and the socioeconomic conditions and may differ significantly. In the case of Poland, collection is carried out using 1100 L containers or plastic bags. Each segregated fraction has an assigned colour, so plastics and metals are collected together in a yellow bag or container. Such a division of selective collection depends on the type of development. It is assumed that waste segregation into the yellow bag will apply to single-family housing, while segregation into the yellow bin will apply to multi-family housing (e.g., multi-storey housing estates). Therefore, we segregate metals and plastics into yellow bags and containers. Figure 1 shows the idea behind this.

In Poland, the method of separate collection of waste is regulated by the Regulation on the detailed method of separate collection of selected waste fractions of 10 May 2021 (Journal of Laws 2021, item 906) [2]. In accordance with the adopted rules, the yellow bag (container) should be filled with waste: plastic waste, including packaging waste, metal waste, including metal packaging waste, and multimaterial packaging waste. In practice, these containers are filled with nonrecyclable plastics and waste not included in the collection paper, textiles, glass, and other components, as shown by the research results presented in this article.

Recycling rates for separately collected plastics are 13 times higher than those collected via mixed streams. Recycling rates achieved from separate plastic collection are 49.4% compared to 3.8% with mixed waste collection [3].

On the other hand, the results of the study [4] showed that the oversieve fraction of mixed municipal waste in Poland still contains 8–13% of secondary raw materials (including plastics) that can be sorted and recycled.

According to EU waste management policy, separate waste collection is seen as a prerequisite for high-quality recycling and achieving the required recycling levels for packaging waste and other secondary raw materials. Collection efficiency and raw material quality are higher when collection is carried out directly at the premises [5]. The introduction of separate waste collection in a door-to-door model allows for improved quantitative effects and ensures high-quality raw materials for recycling. One of the few comparative studies of the systems in force in the EU-28 member states [5] compared the implemented separate collection models and the results achieved in European capitals.

The recycling of plastics is one of the main challenges of the European circular economy [6]. In 2022, global plastics production amounted to 400.3 million tons, of which Europe’s share in this production is 14% [3,7], which corresponds to 56.04 million tons of plastics produced. It should be noted that the amount of plastics produced in Europe in 2006 was 22% compared to 14% in 2022. With global production of 400.3 million tons of plastics, Europe accounts for 56.04 million tons. According to the available data [3], apart from recycling, we also have processes such as thermal use/recovery of energy and the least desirable process of neutralization—landfilling. In 2022, 32.3 million tons of plastics were managed by waste plastics, where the structure of individual processes was as follows: recycling: 26.9%, storage: 23.5%, energy recovery: 49.6%.

In contrast to European data, in Poland, the level of plastics recovery in recycling is at the level of 21.2%, which corresponds to 452 thousand tons of recycled waste plastics.

Of course, in the stream of waste segregated in the yellow bag/container, we also have metals, as the sum of ferrous and non-ferrous metals. According to data [8], in 2022, 4.9% of waste metals from packaging were generated in the European Union. On the other hand, according to the same data, plastics were produced in the EU in general at 19.4%.

For plastic packaging waste, the recycling rate reached 37.8% in 20221 (7 Mt) [3]. This rate will need to improve even further within the next 3 years to reach the 2018 Packaging and Packaging Waste Directive targets of 50% by 2025 and stay on track for 55% by 2030 [9]. Additionally, an important element of regulatory changes in terms of waste plastics introduced by the EU directive (Directive EU 2019/904) [10] concerning single-use plastic products (Single-Use Plastics Directive), the so-called SUP, sanctioned in 2021 to ban and limit the use of 10 disposable plastic products that have environmentally safe alternatives (plates and cutlery, beauty sticks, balloon sticks, polystyrene boxes and cups (EPS), products made of oxo-degradable materials). Another requirement introduced by EU regulations (Directive EU 2019/904) [10] will be an increase in the share of recyclates in PET bottles. Ultimately, by 2030, 30% of PET bottles by weight shall originate from reprocessing. Moreover, by 2025, 77% of plastic bottles will have to be separately collected, and by 2030, this percentage will increase to 90%.

The analysis of the structure of selectively collected municipal waste in Poland provided by the Central Statistical Office is presented below.

Table 1. Selectively collected plastics and metals according to statistical data [11,12,13,14,15,16].

Year	Plastics	Metals	Sum Plastics and Metals	Selectively Collected Municipal Waste	The Amount of Metals and Plastics Separately Collected
	%	%	%	Thousands of Tons	Thousands of Tons
2010	14.4	2.0	16.4	860	141.04
2015	11.9	0.8	12.7	2537	322.20
2019	10.0	0.4	10.4	3977	413.61
2020	9.9	0.1	10.0	4975	497.50
2021	9.6	0.2	9.8	5440	533.12
2022	10.1	0.1	10.2	5361	546.82
2023	10.4	0.1	10.5	5469	574.24

presents statistical data on selectively collected plastics and metals [11,12,13,14,15,16]. The percentage values of the share of plastics and metals in the table below refer to the mass share of these fractions in separately collected waste in particular years in Poland. The last two columns show the total mass of separately collected municipal waste in Poland and the mass of separately collected plastics and metals.

Separate collection of plastics does not guarantee high recycling rates. Not all plastics are recyclable, and there is not always a developed market for individual types of plastics, which is why it is so important to eco-design packaging to make it recyclable [17,18]. Another issue is the economic viability of plastics recycling, especially in terms of cheap crude oil, which is the primary raw material for the production of plastics, which often makes recycled recyclate more expensive than primary raw material.

In European Community the key conditions for the suitability of packaging for material recycling, which include: an organized general system for the collection of a given packaging waste, the functioning of “industrial recycling capacity”, and the creation of packaging and its components that are friendly to recycling [19]. Used packaging can only be recycled if an efficient collection system, segregation, and quality assurance of the recyclate are ensured.

Chemically recycled plastics represent a small share of the total post-consumer recycled plastics. Chemical recycling, as a complement to mechanical recycling, is essential to maximizing the resource potential of plastic waste currently being sent to landfill and incineration. The transition to a plastics circular economy cannot be achieved without a continent-wide roll-out of chemical recycling technology [3].

Poland provides infrastructure for the mechanical recycling of selected types of plastics, but the capacity of recyclers is not always sufficient for the resulting waste stream. Chemical recycling of plastics does not occur in Poland and does not affect the achieved recycling levels, but its development is planned. Exports of plastics to other countries should be limited due to their high environmental footprint of transport, no possibility of controlling their real use, as well as the principle of proximity, according to which waste should be managed close to its origin.

Numerous studies indicate a high share of pollutants in the waste fractions collected separately, as a result of mistakes made in waste segregation, society’s habituation to the system without separate collection, and insufficient environmental education [20,21,22].

These pollutants hamper treatment processes and reduce the value of the achieved levels of recycling and reuse of waste [23].

The aim of the research presented in this article is to determine the quality of the selective collection of plastics and metals for a selected location in Poland, depending on the type of building. The article presents the results of research aimed at analyzing the share of fractions suitable for mechanical recycling, pollutants in waste collected in a yellow bag or yellow container, and a forecast of changes in the morphological composition of selectively collected waste after the introduction of the deposit system in Poland.

2. Research Methodology

Research on the morphological (material) composition of municipal waste involves manually separating the waste into individual fractions and thus determining the proportions of its individual material components. Depending on the needs, morphological analysis can be expanded to include additional subfractions of the main waste components, enabling detailed analysis, for example, regarding the potential for waste recycling. For example, plastics can be sorted into specific commercial assortments, including poly(ethylene terephthalate) (PET), polyethylene (PE), high-density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS). Additionally, PET can be separated into colors—blue, green, and colorless.

In research, polystyrene was divided into packaging polystyrene (PS) (unexpanded) and expanded polystyrene (e.g., trays or pieces of styrofoam used for packaging electronics and as thermal insulation for buildings). Hard plastics are a type of polymer characterized by high stiffness and mechanical strength, primarily HDPE, e.g., fruit crates. They constitute a separate commercial assortment at municipal waste sorting plants, which is why this group was distinguished in this research.

Obtaining reliable and representative tests of the morphological composition of waste requires the adoption of an appropriate test methodology, which takes into account the method of sampling, its weight, the number of samples taken, the time and place of collection, taking into account the variability of the morphological composition of waste depending on the season, type of buildings, size of the city and other factors.

The research was carried out in the Silesian agglomeration in one of the waste sorting plants. The research was carried out in an area inhabited by 170,000 people. Two scales were used to study the morphological composition: a platform scale and a hook scale with a weighing accuracy of 20 g. Samples for testing with a defect of about 100 kg were collected in accordance with the established procedure, ensuring the representativeness of the tests performed.

One sample for testing the morphological composition of waste from the selective collection of plastics and metals from bag collection from single-family housing consisted of 40–50 full, so-called “yellow bags” selected randomly from various places collected in the hall for the receipt of selectively collected waste in the bag system.

One sample for testing the morphological composition of waste from selective collection of plastics and metals from container collection from multi-family housing (blocks) was taken from a waste heap with a volume of at least 10 m³ with a snow shovel, collecting waste alternately from the top, from the middle, from the bottom, and from different sides of the heap until a sample weighing about 100 kg was obtained.

The morphological composition of waste was carried out in accordance with the methodology recommended by the former Department of Economy of the Ministry of the Environment, based on the Solid Waste Analysis Tool methodology developed as part of the EU research project [24,25].

In the SWA-Tool methodology, the basic principle is to stratify data based on seasons, types of buildings, collection systems, etc. As part of the research, waste was divided into as many as 20/21 material categories, thanks to which the results obtained are a valuable source of information on the quality of selective collection depending on the type of construction, as well as the possibility of further sorting and use of waste.

3. Results

In accordance with the adopted research methodology, studies were conducted on the morphological composition of selectively collected municipal waste fractions. This waste was collected in a yellow bag/container (depending on the type of building where the waste came from), which, according to regulations, should be used for plastics and metals.

Table 2. Results of morphological composition of selectively collected plastics and metals for multi-family housing (blocks)—“yellow container”.

	Fraction Name:	Value Range (June Samples)	Value Range (September Samples)	Average Value	Standard Deviation
		[%]	[%]	[%]	[%]
1	PET colorless (after drinks and mineral water)	6.76–10.67	6.75–9.07	8.31	1.66
2	PET green (after drinks and mineral water)	2.49–2.69	2.27–2.68	2.53	0.17
3	PET blue (after drinks and mineral water)	6.73–7.54	7.06–7.69	7.26	0.38
4	PET other (white, brown, red and other colors, after oils, vegetable trays, PET after household chemicals and after milk)	4.12–5.75	6.03–8.19	6.02	1.45
5	Foils (mix of colors and types)	14.27–20.61	18.66–20.21	18.44	2.51
6	HDPE packaging, PP packaging (household chemicals, food packaging, cups, trays, containers, caps)	9.22–10.97	9.51–13.03	10.68	1.51
7	PS packaging	0.11–2.11	0.01–0.34	0.64	0.86
8	The so-called “hard plastics”	1.3–6.44	3.22–5.85	4.20	2.07
9	PVC	0.3–1.48	0.22–0.69	0.67	0.50
10	Rubber	0.53–0.67	0.39–0.65	0.56	0.11
11	Ferrous metals	3.50–3.71	5.05–6.88	4.79	1.35
12	Non-ferrous metals	2.72–3.19	2.80–3.66	3.10	0.37
13	Hazardous waste	0.50–1.03	0.28–0.98	0.70	0.32
14	Liquid food packaging	3.05–3.42	2.55–3.05	3.02	0.31
15	Multi-material waste (other than Liquid food packaging)	0.28–1.08	0.11–0.60	0.52	0.37
16	“Other” 7	2.63–3.91	2.73–3.28	3.14	0.51
17	Plastics difficult to identify—no marking	0.55–3.91	0.50–1.01	1.49	1.41
18	Pollution (waste not included in the collection—mainly paper, cardboard and textiles, but also glass, diapers, organic and mineral waste)	17.95–32.29	20.65–21.49	23.08	5.47
19	Polystyrene—polystyrene and other trays (expanded polystyrene)	0.28–0.99	0.63–0.85	0.69	0.27
20	LDPE packaging	0.0–0.25	0.11–0.27	0.16	0.11
	SUM:			100

presents the results of morphological composition tests of selectively collected plastics and metals for multi-family housing (blocks)—“yellow container”.

Table 3. Results of morphological composition of selectively collected plastics and metals from single-family housing—“yellow bag”.

	Fraction Name:	Value Range (June Samples)	Value Range (September Samples)	Average Value	Standard Deviation
		[%]	[%]	[%]	[%]
1	PET colorless (after drinks and mineral water)	8.19–9.38	7.22–11.10	8.97	1.45
2	PET green (after drinks and mineral water)	1.88–2.25	1.78–2.84	2.19	0.42
3	PET blue (after drinks and mineral water)	6.58–7.63	8.04–12.40	8.66	2.22
4	PET other (white, brown, red and other colors, after oils, vegetable trays, PET after household chemicals and after milk)	3.91–4.70	5.87–7.16	5.41	1.23
5	Foils (mix of colors and types)	26.07–32.93	20.71–29.91	27.41	4.57
6	HDPE packaging, PP packaging (household chemicals, food packaging, cups, trays, containers, caps)	9.04–13.86	11.21–12.71	11.71	1.80
7	PS packaging	0.58–1.21	0.30–0.31	0.60	0.37
8	The so-called “hard plastics”	3.25–4.28	1.69–3.32	3.14	0.37
9	PVC	0.11–1.07	0.00–1.15	0.58	0.53
10	Rubber	0.46–1.21	0.00–0.21	0.47	0.46
11	Ferrous metals	3.69–4.95	4.02–6.28	4.74	1.00
12	Non-ferrous metals	3.41–5.77	4.33–6.89	5.10	1.33
13	Hazardous waste	0.53–1.53	0.18–0.48	0.68	0.51
14	Liquid food packaging	3.60–4.32	4.22–5.62	4.44	0.73
15	Multi–material waste (other than Liquid food packaging)	0.73–1.06	0.00–0.34	0.53	0.40
16	“Other” 7	3.79–4.31	2.43–5.00	3.88	0.94
17	Plastics difficult to identify—no marking	1.91–2.80	1.36–2.02	2.02	0.51
18	Pollution (waste not included in the collection—mainly paper, cardboard and textiles, but also glass, diapers, organic and mineral waste)	6.85–8.86	7.13–9.66	8.13	1.17
19	Polystyrene—polystyrene and other trays (expanded polystyrene)	0.84–1.21	0.18–0.19	0.60	0.44
20	LDPE packaging	0.27–0.99	0.00	0.32	0.41
21	Toys	0.00	0.0–1.78	0.45	0.77
	SUM:			100

presents the results of tests on the morphological composition of selectively collected plastics and metals for single-family housing—“yellow bag”.

Table 4. Forecast of the impact of the deposit system in Poland on the morphological composition of selectively collected plastics and metals for multi-housing (blocks of flats).

	Fraction Name:	Morphological Composition of Selectively Collected Plastics and Metals for Multi-Family Housing (Blocks of Flats) Before the Entry into Force of the Deposit System in Poland	Deposit System in Poland
			1 Year Efficiency 75%	2 Year Efficiency 80%	3 Year Efficiency 90%
		[%]	[%]	[%]	[%]
1	PET colorless (after drinks and mineral water)	8.31	2.46	1.99	1.02
2	PET green (after drinks and mineral water)	2.53	0.74	0.61	0.31
3	PET blue (after drinks and mineral water)	7.26	2.14	1.73	0.89
4	PET other (white, brown, red and other colors, after oils, vegetable trays, PET after household chemicals and after milk)	6.02	7.12	7.20	7.38
5	Foils (mix of colors and types)	18.44	21.80	22.06	22.62
6	HDPE packaging, PP packaging (household chemicals, food packaging, cups, trays, containers, caps)	10.68	12.62	12.79	13.10
7	PS packaging	0.64	0.76	0.77	0.79
8	The so-called “hard plastics”	4.20	4.96	5.02	5.15
9	PVC	0.67	0.79	0.80	0.82
10	Rubber	0.56	0.66	0.67	0.69
11	Ferrous metals (2% steel cans)	4.79	5.58	5.64	5.76
12	Non-ferrous metals (75% aluminum beverage cans)	3.10	1.60	1.48	1.24
13	Hazardous waste	0.70	0.83	0.84	0.86
14	Liquid food packaging	3.02	3.57	3.61	3.70
15	Multi–material waste (other than Liquid food packaging)	0.52	0.61	0.62	0.64
16	“Other” 7	3.14	3.71	3.76	3.84
17	Plastics difficult to identify—no marking	1.49	1.76	1.78	1.83
18	Pollution (waste not included in the collection—mainly paper, cardboard and textiles, but also glass, diapers, organic and mineral waste)	23.08	27.28	27.61	28.31
19	Polystyrene—polystyrene and other trays (expanded polystyrene)	0.69	0.82	0.83	0.85
20	LDPE packaging	0.16	0.19	0.19	0.20
	SUM:			100

presents a forecast of the impact of the deposit system in Poland, which will be in force from 1 October 2025, on the morphological composition of selectively collected plastics and metals for multi-family housing (blocks of flats).

The following assumptions were made for the forecast:

• It was assumed that in the first year of operation, the deposit system would be 75% effective, in the second year 80%, and in the third year 90%. The assumed effectiveness applies to all packaging covered by the deposit system;
• It was assumed that the deposit system will cover: 100% of the fraction weight—“colorless PET” (the share of 5l of mineral water bottles was omitted), “green PET”, “blue PET”, 2% of the “ferrous metals” fraction in the form of steel beverage cans, 75% of the weight of the “non-ferrous metals” fraction in the form of aluminum beverage cans;
• It was assumed that the share of fractions not covered by the deposit system in the following years after the entry into force of the deposit system would be constant—the same as before the entry of the deposit system in Poland.

Table 5. Comparison of the efficiency of collection and the possibility of mechanical recycling of selectively collected plastics and metals, depending on the type of housing.

Selective Collection of Plastics and Metals Depending on the Type of Housing	“Yellow Container”—Multi-Family Housing [%]	“Yellow Bag”— Single-Family Housing [%]
Pollution (waste not included in the collection—mainly paper, cardboard and textiles, but also glass, diapers, organic and mineral waste)	23	8.1
Share of mechanically recyclable plastics and metals in relation to the entire mass of waste fractions collected (estimated according to Equation (1))	58	67
Possibility of separating plastics and metals from automated sorting plants assuming a sorting efficiency of 85%	49	57

presents a comparison of the efficiency of collection and the possibility of mechanical recycling of selectively collected plastics and metals, depending on the type of development (before the deposit system came into force in Poland).

$$\mathrm{X}=\mathrm{a}+0.5\mathrm{b} \left[\mathrm{\%}\right]$$

(1)

where:

• X—estimated quantity and the weight of mechanically recyclable plastics and metals—adopted based on knowledge of the sales market in Poland [%]
• a—it is assumed that 100% of the following fractions are suitable for mechanical recycling: (colorless PET, blue PET, green PET, HDPE and PP packaging, PS packaging, so-called hard plastics, ferrous metals, non-ferrous metals, Liquid food packaging, expanded polystyrene, LDPE packaging) [%]
• b—it is assumed that 50% of the following fractions are suitable for mechanical recycling: (foil, other PET) [%]

4. Discussion of Results

Regarding the morphological composition of waste collected as a part of the selective collection of plastics and metals, where representative samples of waste were collected from multi-family housing (the so-called blocks), collection in yellow containers was dominated by pollution (23%)—waste not covered by the collection—which consisted mainly of paper, cardboard and textiles, but also glass, diapers, organic and mineral waste. The second largest fraction of film (18.4%) was of various types and colors. PP and HDPE packaging accounted for 10.7% of the morphological composition of the tested waste, colorless PET accounted for 8.3%, blue PET accounted for 7.26%, and green PET accounted for 2.5% of the weight of the tested waste. Ferrous metals accounted for 4.8% and non-ferrous metals for 3.1% of the weight of the surveyed waste. Other recyclable fractions include Liquid food packaging (3.0%), PS (0.64%), “hard” plastics (4.2%), polystyrene (0.69%), and other PET 6.0%. Hazardous waste was mainly packaging of hazardous chemicals and medical waste from households (0.7%).

In the morphological composition of waste collected as part of the selective collection of plastics and metals, where representative samples of waste were collected from bag collection, the so-called “yellow bags” (single-family housing), the fraction of foil (27.4%) of various types and colors dominated. Significant predominance (27.4%) of the foil fraction in the “yellow bags” is due to the greater involvement of residents of single-family homes in waste collection. The ability to monitor the quality of waste collected in transparent bags encourages residents to ensure that all plastics are disposed of in yellow bags. In multi-family buildings, a significant portion of plastics in the form of foil ends up in mixed municipal waste, as research has shown [4].

A large share was characterized by contamination (8.1%)—waste not covered by collection—which consisted mainly of paper, cardboard, and textiles, but also glass, diapers, and organic and mineral waste. PP and HDPE packaging accounted for 11.7% of the morphological composition of the tested waste, colorless PET accounted for 9%, blue PET accounted for 8.7%, and green PET accounted for 2.2% of the weight of the tested waste. Ferrous metals, like non-ferrous metals, were characterized by a similar share and constituted about 5% of the weight of the studied waste. Other recyclable fractions include Liquid food packaging (4.4%), PS packaging (0.6%), so-called “hard” plastics (3.1%), polystyrene (0.6%), or other PET 5.41% (for which there is limited market demand). Hazardous waste was mainly packaging of hazardous chemicals and medical waste from households (0.7%).

The results of the research carried out at the beginning of summer and autumn in the months of June and September were similar in terms of the share of individual fractions, which may be due to the fact that these are months that are part of the barbecue season with similar high temperatures during the day, which is conducive to high consumption of packaged beverages.

5. Conclusions

The conducted research showed significant differences in the quality of selective collection of plastics and metals depending on the type of construction in which the collection is carried out. In single-family housing, the quality of selective collection of plastics and metals is much better, as evidenced by the lower content of pollutants, i.e., waste not covered by collection—about 8% of them are in the yellow bag and about 23% in the yellow container. This may be due to the fact that residents of single-family housing pay more attention to selective waste collection, as well as that the waste displayed in front of the property in a transparent yellow bag is visually inspected by collectors, and in multi-family housing, there is anonymity, which is not conducive to the quality of selectively collected plastics and metals. It should be noted that in multi-family housing, selective collection takes place in up to 1100 L containers, where control is impossible in many cases. Therefore, it is necessary to further educate residents dedicated primarily to residents of multi-family housing.

This paper presents a forecast of changes in the morphological composition of selectively collected plastics and metals for the three-year period after the entry into force of the deposit system in Poland, i.e., from 1 October 2025. The deposit system will cover separately collected plastics and metals, PET bottles (up to 3 L in volume), and metal beverage cans (up to 1 L in volume), which will affect not only the morphological composition of the collected plastics and metals, but also the revenues of waste sorting plants to which the waste was sent before the deposit system came into force. Colorless PET bottles and aluminum beverage cans represent two of the most valuable secondary raw materials of all waste, accounting for around 50% of waste sorting plants’ revenues from their sales and recycling documents.

The research showed what part of the selectively collected plastics and metals, depending on the type of construction, can be mechanically recycled, taking into account the existing market and the efficiency of waste sorting. The analysis of the morphological composition of waste showed that mechanical recycling of selectively collected plastics and metals in single-family housing after the sorting process can include 57% of the weight of collected waste in the yellow bag and 49% of the weight of collected plastics and metals from multi-family housing from the so-called yellow container. Other waste that will not be recycled mechanically or chemically should be managed as an alternative fuel as part of the energy recovery process [26].

Used packaging can only be recycled if an efficient collection system, segregation, and quality assurance of the recyclate are ensured.

The recycling system in Poland needs to be changed to increase the recycling plastic recycling rates achieved by: changing the existing mechanisms of Extended Producer Responsibility—the system should receive many more financial resources and place a greater burden on producers of non-recyclable packaging; developing chemical recycling of plastics; implementing eco-design for plastic packaging and products. The authors of the publication [6] also draw attention to: making certain products compulsory for a minimum content of recycled materials and introducing standardization and certification of the quality of recyclates. This will level the opportunities and open new markets for recycled plastics with uniform and repeatable properties, while ensuring good characteristics, quality, and safety of products.

After the introduction of the deposit system in Poland, there will be a plan to carry out further tests of the morphological composition of selectively collected plastics and metals, which will allow us to verify the forecasts adopted in the article.