Best available technology options for the mitigation of environmental impacts in waste plastics

Abstract

The best available technology (BAT) for waste plastics relies on their components and the right technology employed, while the quality of waste plastics depends on the original plastics and the source separation processes simultaneously. In this study, the quality of waste plastics and the potential recycling processes, including recycling granulation, pyrolysis to oil, Green-RDF and incineration technology, were co-related from the economic and technical perspective. A database was established for waste plastic components, considering factors such as plastic fraction, waste composition, moisture content, and impurity rate. The corresponding environmental impacts for the typical resource processes were assessed by life cycle analysis (LCA) and cost–benefit analysis combined. It was found that around 23% ± 1% of waste plastics in residual waste had the resource potential if the stricter classification criteria of plastic wastes were adopted, such as the components, moisture content less than 5% or 8% and impurity rate less than 8%. Pyrolysis to oil had the best environmental benefits in GWP100, reaching -1,683.51 kg CO₂ equivalent (CO₂-eq), determined as the best method for high-value plastics, and incineration depicted poor environmental benefits for low-value plastics. The net income of recycling granulation for middle-value waste plastics would achieve 1383 ± 35 yuan/ton through cost–benefit analysis, which represented the optimal economic benefits. CO₂ emissions for waste plastics could be mitigated around 29.74% by matching BATs compared to the current management system, which would provide policymakers with proper recommendations in terms of the adaptability of waste plastic sources and technologies.

Highlights

Best available technology was assessed based on the characteristics of waste plastics.

23%±1% of waste plastics in residual waste could be extracted for resource utilization.

Pyrolysis and granulation performed well in both environmental and economic impacts.

The employment of BATs in residual waste contributed to 29.74% CO₂ reduction.

Introduction

The usage of takeout boxes, courier packaging, and various plastic products continues to rise in our daily lives, and the global annual production of plastic has exceeded 390 million tons by 2021 [21]. Plastic is an important carrier of fossil carbon, and the co-emission of carbon and pollutants are involved during the entire production, utilization, and treatment processes [11, 22], which approximately 5.5–6.0 tons of CO₂ were released for 1 kg of new plastic producing [12], and over 56 billion tons were supposed to be generated by 2050 [16]. Currently, less than 10% of waste plastics in recyclables with high quality, such as Acrylonitrile butadiene styrene (ABS) are recycled through recycling granulation [7, 24], while most of the other medium and low-value waste plastics are utilized by incineration, sacrificing the effectiveness of resource utilization, and resulting in poor environmental benefits [3]. The pivotal aspect of the resourceful utilization of discarded plastic relies on the systematic classification and quality-based recovery of waste plastics using diverse technologies to maximize the value extracted from the recycling of waste plastics.

The environmental benefits and technology feasibility derived from the recycling of waste plastics are primarily concentrated on investigations conducted by individual resource utilization technology enterprises. Some works have conducted an analysis of the environmental impacts associated with a specific disposal technology, such as the production of recycled materials, pyrolysis for oil production, and power recovery [1, 4, 6, 15, 19, 20]. Several studies on the potential impacts stemming from advancements in recycling technologies have also investigated the technological iterations within the plastic industry in both China and the global economic context [13]. Certain research endeavors have analyzed the environmental pollution issues resulting from the efficiency and energy characteristics of the waste plastic recycling process, and the relationships among raw materials, disposal technologies, and secondary pollutants [14, 15]. Variations in the sources of waste generation across different studies have hindered comparability in the environmental impact of diverse waste plastic disposal technologies, and the economic benefits of waste plastic disposal have not been incorporated into consideration. It is crucial to propose a rule to match the components of waste plastics with BATs, reaching optimal environmental benefits, especially for the waste plastics discarded from the municipal solid waste sectors.

Shanghai has been implementing a four-category waste classification policy since 2019 [26]. Over the past four years, there has been sufficient data accumulation related to garbage classification. The classification features and production characteristics of waste plastics after garbage sorting can be distinctly delineated at both the source and the transfer point. Waste plastics are primarily classified into recyclables and residual waste, and most of the waste plastics with medium/low values are predominantly incinerated. Addressing how to achieve high-value resource utilization of waste plastics in residual waste and mitigate its environmental impact has emerged as a pivotal concern in waste classification, which would improve the waste source separation efficiency.

In this work, the generation features of waste plastics in municipal solid waste (MSW) are surveyed from the components and the generation rate initially, providing an overview of the incoming requirements for various types of plastic waste in mainstream disposal technologies. The relationship between the quality of waste plastics and the appropriate resource recovery techniques available was reviewed and summarized. Subsequently, the environmental and economic benefits of four mainstream large-scale waste plastic treatment technologies are assessed by the LCA method and cost–benefit model combined, and key factors influencing the environmental benefits of different disposal technologies are identified during this evaluation process. Within the frame of refined waste categorization, the recycling potential of waste plastics in residual waste is finally explored by matching different waste plastic components with the BATs.

Materials and methods

Data collection

Waste plastics properties in MSW

To obtain the actual production of household waste plastics in Shanghai, the annual data were firstly obtained on the production of residual waste and recyclables from the Shanghai Greenery and Public Sanitation Bureau. The proportion of particulate waste was extracted in residual waste from the "Annual Report on Physical and Chemical Characteristics Investigation of Shanghai Municipal Solid Waste," which was issued by Shanghai Urban Construction Investment and Development Corporation. The proportion of waste plastics in recyclable materials was retrieved from the Shanghai Municipal Recyclable Materials Digital Management Platform, and the relevant data covered the period from 2016 to 2022. Collaborating with the Shanghai Academy of Environmental Sciences, five transfer stations and distribution centers scattered in different regions were investigated to verify the specific flow of domestic plastic waste in Shanghai (See Table S1).

Classification criteria

To explore the requirements of different waste plastics disposal technologies, on-site investigations were conducted on representative end-of-life disposal enterprises with relevant different technologies, which aimed to summarize the original requirements of various end-of-life disposal technologies for waste plastics. Data collection primarily stemmed from the dominant domestic enterprises involved in mechanical recycling and chemical recycling, and original material standards for various waste plastic disposal technologies were also coupled with literature reviews [4, 8, 20] and the Chinese national standard numbered GB/T 37821–2019.

Plastics resource matrix in residual waste

To explore the maximum recycling potential after refined management of waste plastics, one 3-month component analysis of residual waste was conducted in a typical enterprise called Laogang, which was equipped with the highest residual waste processing capacity in Shanghai. Residual waste was mainly used for incineration, while currently the company aimed to refine the classification of residual waste and extract recyclable materials from residual waste for reuse. The residual waste components came from domestic sources such as Baoshan District and Lingang District, and the components were taken from the average value.

Classification criteria and waste plastics resource matrix

Material requirements of BATs

By matching on-site enterprise research information, literature review of waste plastic disposal technology and Chinese national standards, pyrolysis to oil technology was regarded as the highest requirement for waste plastic materials, followed by recycling granulation, Green-RDF, and incineration. The main raw materials for pyrolysis to oil were PP and PE, which were generally obtained by free radical polymerization. The hydrocarbon-containing compounds in the pyrolysis products could be used to produce basic chemicals. The detailed related standards were shown in Table 1.

Table 1. Material requirements for different waste plastic disposal technologies

	Recycling Granulation	Pyrolysis to Oil	Green-RDF	Incineration
Material requirements	1) Original materials should ideally be free of PVC and the disposal process cannot handle composite films 2) An impurity content of less than 8% and a moisture content of less than 5%	1) For miscellaneous films from domestic sources (mainly express bags, garbage bags, and shopping bags), the original materials require PE/PP as the main materials, (PE, PP, PS) > 95% 2) PS < 20%; LDPE > 50%; HDPE < 50%; PP < 50% 3) PET < 1%; PVC < 1%; 4) Moisture content (after pretreatment and drying) < 5%	1) The moisture content is less than 8% 2) Plastic domestic waste	Plastic Domestic waste

Waste plastics resource matrix

Two main types of plastics in residual waste could be further classified namely plastic films (~ 15%) and rigid plastics (~ 8%). The plastic film consisted of 8% PE film and 7% composite film, and the rigid plastic consisted of 3.5% PP, 2% PS, PET 1.7%, 0.5% HDPE, and 0.2% PVC. The specific types and their proportions were detailed in Fig. 1.

Fig. 1 [Images not available. See PDF.]

Residual waste from domestic sources in Shanghai

LCA method and process description

LCA method and EASEWASTE software

LCA method was increasingly favored and widely applied in environmental impact analyses across various fields, such as energy [18], construction [23], livestock sectors [17], and waste management [2]. EASEWASTE software employs the Danish Environmental Design of Industrial Products (EDIP 1997) as its impact assessment method, providing results at four distinct levels including life cycle inventory (LCI), characterization of impacts, normalized impact profile, and weighted impact profile [5, 10]. The characterization phase translated and aggregated emissions into environmental impact potentials, expressed in terms of characterization values [10, 25], and the typical values were enumerated in Table S2 in SI. The analysis of the characterized pollutant emission inventory included nine types of environmental impacts, including greenhouse effect (GW), photochemical ozone formation (POF), ozone layer depletion (OD), acid deposition (AC), and eutrophication (NE), human toxicity (HTs), ecotoxicity (ETs), groundwater contamination (SGR) and persistent ecotoxicity (SETs). The temporal scope of the impacts considered was 100 years, predominantly influencing the characterization concerning global warming. The functional unit for LCA was the environmental benefit change of processing 1 ton of waste plastic throughout the whole life cycle.

Process description

Around 23% ± 1% of waste plastics in residual waste could be better for resource utilization based on the classification criteria of waste plastics on components, with moisture content less than 5% or 8% and impurity rate less than 8%. The treatment process involved using the granulation method for processing PET and PS waste plastics, employing pyrolysis for oil production to handle PP and PE waste plastics, and utilizing Green-RDF technology for processing PVC and composite film waste plastics. Components in residual waste that could not be utilized were treated through incineration technology (approximately 77%). The four facilities employing these disposal technologies were all situated in Shanghai, with the waste plastic materials sourced from domestic waste.

The system boundary for recycling granulation was illustrated in Fig. 2A. This system encompassed energy input, additional material input, recovery of recycled plastic particles, solid waste disposal, and pollution control. In the waste disposal process, the primary waste generated consisted mainly of waste plastic scraps, which could be further recycled; hence, the solid waste disposal process primarily involved recycling. The system boundary for pyrolysis to oil was depicted in Fig. 2B. This system comprised energy input, additional material input, recovery of pyrolysis oil, solid waste disposal, and pollution control. Notably, the generated solid waste from this company was non-recyclable, necessitating an incineration-based solid waste disposal process. The system boundary for Green-RDF was shown in Fig. 2C, which involved energy input, additional material input, energy recovery, and pollution control. The system boundary for incineration was illustrated in Fig. 2D, which encompassed energy input, additional material input, energy recovery, and pollution control. The LCI of four different waste plastic disposal processes was shown in Table S3 in SI.

Fig. 2 [Images not available. See PDF.]

The system boundary of four different disposal technologies. A: recycling granulation, B: pyrolysis to oil, C: Green-RDF, D: incineration

Sensitivity analysis

Sensitivity analysis constituted a crucial component of LCA as it revealed the impact of chosen data and assessment methodologies on LCA outcomes. The sensitivity coefficient was regarded as a metric to assess the robustness of results, gauging the extent to which minor alterations in input data translate into variations in output results. These coefficients played a vital role in pinpointing sensitive processes and parameters, commonly referred to as critical factors, thereby informing the need for meticulous data collection and uncertainty analysis [9]. In this work, sensitivity analysis was employed to analyze the environmental impact of different waste plastic disposal technologies in response to variations in recycling yield rates.

Scenario analysis

Three scenarios including high-level, baseline-level, and low-level were detailed in Table 2.

Table 2. Scenarios for potential resource utilization of waste plastics in residual waste

Low-level scenario	Base-level scenario	High-level scenario
5% waste plastics in residual waste converted to recyclables, of which 2% PE, 1% PP, 0.5% PS, 0.5% PET, 1% composite film	10% waste plastics in residual waste converted to recyclables, of which 3% PE, 2% PP, 1% PS, 1% PET, 3% composite film	15% waste plastics in residual waste converted to recyclables, of which 4% PE, 3% PP, 1.5% PS, 1.5% PET, 5% composite film

Results

Waste plastics properties in MSW

It was observed that the production of household waste plastics in Shanghai surged from 575,400 tons in 2016 to 1,655,100 tons in 2022. These domestic plastics were predominantly found in residual waste. However, the proportion of plastics in residual waste exhibited a consistent decline annually from 2019 to 2022, which underscored the efficacy of waste classification initiatives. In 2022, the household waste plastic production reached 1,655,100 tons, with recyclables constituting 11.63% of the total volume (See Fig. S1). Waste plastics were primarily categorized into two major segments: residual waste (88.4%) and recyclables (11.6%). Within the residual waste, miscellaneous waste plastics constituted 86.3%, and waste plastic bottles accounted for 2.1%. As for the recyclables, they are further classified into three types including waste PS foam (0.5%), waste PET bottles (6.2%), and waste hybrid plastics (4.9%) (Fig. 3).

Fig. 3 [Images not available. See PDF.]

The source flow and classification of Shanghai’s domestic waste plastics

Through on-site investigations and coupling with the standards of material requirements, different categories of plastic waste were matched with various end-of-life disposal technologies. This exploration aimed to uncover the potential environmental benefits of BAT. Incineration is a disposal technique with relatively poor environmental benefits, and prioritizing other disposal technologies for waste plastics with better environmental outcomes would be highly beneficial for environmental impacts. Pyrolysis to oil (11%) technology was employed for the disposal of PE film (7%) in plastic films and 3.5% PP and 0.5% HDPE in rigid plastics. Recycling granulation (~ 4%) technology was used to dispose of 2% PS and PET 1.7%. Green-RDF (~ 8%) was used to treat 0.2% PVC and 7% composite membrane, and other remaining components were incinerated (Fig. 4).

Fig. 4 [Images not available. See PDF.]

Actual and theoretical “material-technology” matching of residual waste plastics

Environmental impacts

GWP100 and other environmental impacts

This work assessed the environmental impacts of four parts including GWP100, AC, NE, POF, and ES (Fig. 5). CH₄ and CO₂ were identified as key factors influencing GWP100, with CH₄ emerging as a key factor affecting POF. NOx and P emerged as key factors affecting NE, while Chloroform was pinpointed as a key factor impacting ES. NO_x and SO₂ were recognized as key factors affecting AC.

Fig.5 [Images not available. See PDF.]

GWP100 and environmental indicators under different technologies

According to the results of GWP100, pyrolysis to oil had the best environmental benefits, followed by recycling granulation, Green-RDF (refuse-derived fuel) and incineration. Despite accounting for the substitution effect of electricity generation, incineration remained a carbon-positive disposal technology. Regarding the impact on global warming, employing pyrolysis-to-oil technology was estimated to yield approximately -869.58 kgCO₂-eq. Notably, pollution control emerged as the primary contributor to the positive carbon effect, generating around 719.55 kgCO₂-eq. Conversely, the oil recovery from pyrolysis oil stood out as the predominant factor driving the negative carbon effect, amounting to -1,683.51 kgCO₂-eq. Consequently, pyrolysis-to-oil technology presented itself as a disposal method with optimal environmental benefits. Given Green-RDF and incineration disposal technologies, the whole process emitted large amounts of CH₄ and CO₂ which caused poor overall environmental benefits. Even incineration has become a positive carbon disposal technology, with 1,562.5 kgCO₂-eq. The GWP100 of recycling granulation disposal technology was slightly different from the above three technologies. The largest contributor to carbon-positive environmental benefits was electricity consumption, with 289.36 kgCO₂-eq. Regenerated particles had a strong negative carbon effect in replacing primary particles, which caused the overall carbon emissions of recycling granulation -130.75 kgCO₂-eq.

Each ton of waste plastic recycling granulation caused environmental impacts of 6.57 kg SO₂-eq, 3.83 kg NO₃-eq, 0.06 kg C₂H₄-eq and -0.59 m³ soil respectively on AC, NE, POF and ES. In addition, each ton of waste plastic pyrolysis to oil treatment technology caused environmental impacts of -0.50 kgSO₂-eq, 5.34 kg NO₃-eq, 0.33 kg C₂H₄-eq and -14.01 m³ soil respectively on AC, NE, POF and ES. Each ton of waste plastic Green-RDF treatment technology caused environmental impacts of -31.76 kgSO₂-eq, -17.21 kgNO₃-eq, -0.25 kg C₂H₄-eq and -23.92 m³ soil respectively on AC, NE, POF and ES. Furthermore, each ton of waste plastic Incineration treatment technology caused environmental impacts of -7.12 kg SO₂-eq, -1.82 kg NO₃-eq, -0.14 kg C₂H₄-eq and -6.69 m³ soil respectively on AC, NE, POF and ES. Green-RDF showed advantages in AC, NE, POF and ES compared to pyrolysis to oil, incineration, and recycling granulation. In terms of AC and ES, the environmental benefits of regenerating granulation technology were significantly different from other disposal technologies. This was primarily due to the inferior reduction effect of recycled particles instead of primary particles on SO₂ and Chloroform was not as good as other disposal technologies. In terms of POF and NE, there was a significant gap in the environmental benefits of pyrolysis to oil compared with other disposal technologies, which attributed to the greater production of SO₂ and NO_x during the pyrolysis to oil process compared to other technologies.

For the four disposal technologies, the key factors contributing to distinct environmental impacts also varied. The environmental benefits of incineration and Green-RDF were favorable due to the key role of electricity generation in replacing related pollutants. While pyrolysis to oil technology emitted far more SO₂ and NO_x than other disposal technologies during the disposal process.

Changes in recovery yield of substitute products

Sensitivity analyses were conducted to investigate the results influenced by the recovery yield of substitute products. Chen et al. [4] conducted a sensitivity analysis on the yield of different recycling alternatives for waste plastic mechanical recycling and incineration disposal technologies, and Stančin et al. [20] also adopted a relevant sensitivity analysis in waste plastic pyrolysis to oil technology. This study assumed that the recovery alternative yields of pyrolysis to oil, Green-RDF, mechanical recycling, and incineration each increased by 1% and 3% respectively, and explored the changes in the environmental benefits of the four disposal technologies under different recovery alternative yields. A 1% increase in the output of regenerated granulation was labeled as RR1%, and a 3% increase was labeled as RR3%. Similarly, the changes in recovery yields of pyrolysis to oil, Green-RDF, and incineration were recorded as PTO1% and PTO3%, RDF1% and RDF3%, and I1% and I3%, respectively. When the yield of recycled alternatives increased by 3%, Green-RDF would surpass recycling granulation and become the second largest carbon-negative resource utilization technology for waste plastics, followed by pyrolysis to oil.

As far as POF was concerned, the change in yield had little impact on the results. When the yield was increased by 3%, the POD of Green-RDF and incineration technology would decrease by 0.02 and 0.01 kg C₂H₄-eq respectively, compared with the case where the yield was increased by 1%. As for AC, changes in yield had little impact on the results as well. When the yield was increased by 3%, the AC of pyrolysis oil production, Green-RDF and incineration technology would decrease by 0.2, 0.8 and 0.2kg SO₂-eq respectively compared with the case where the yield was increased by 1% (Fig. 6).

Fig.6 [Images not available. See PDF.]

Changes in GWP100, POF & AC under different recycling alternative yields

Economic benefits

The net income from waste plastic granulation was the highest, reaching 1,383 ± 35 yuan/ton. The economic benefits of other waste plastic technologies such as Green-RDF, pyrolysis to oil and incineration were 952 ± 15 yuan/ton, 666 ± 20 yuan/ton, and 16 ± 5 yuan/ton respectively. In terms of cost, incineration had the lowest disposal cost, while the cost of regenerating granulation and pyrolysis to oil technologies was higher, mainly due to the higher cost of raw materials and higher industrial water consumption. Although the costs of recycled granulation and pyrolysis for oil production were higher, the value of the produced recycled particles and heavy oil contributed to higher sales revenue, resulting in a favorable net income. Based on the previous environmental impact results, pyrolysis to oil demonstrated the best environmental benefits, while it ranked third among the four waste plastic disposal technologies from the economic perspective. If applying pyrolysis to oil technology on a large scale was considered in the future, it would be essential to obtain higher value products from pyrolysis. Efforts should be made to explore whether there were potential solid waste byproducts generated during the pyrolysis process that could be recycled, thereby reducing the costs associated with pyrolysis for oil production. In this way, the disposal technology with the best environmental benefits could be mass-produced and applied on a large scale, and its maximum value for environmental benefits could be brought into play (Fig. 7).

Fig.7 [Images not available. See PDF.]

Economic benefits of four waste plastic disposal technologies

Discussions

Potential environmental benefits for applying BATs

Employing the grey prediction model GM (1, 1), a forecast for the generation of residual waste in the year 2025 was conducted (See Text S1), yielding a predicted value of 2.02E + 09 tons. The carbon emission in the base-level scenario was 6.73% lower than in the low-level scenario, while carbon emission in the high-level scenario was 13.45% lower than in the low-level scenario. Using the results regarding the environmental benefits of disposal technologies and the waste plastics production data disposed by each technology as the data source, it was evaluated that the carbon emissions could be reduced by 29.74% when applying BATs to reach the best environmental benefits (See Fig. S2 & Text S2).

Limitations and recommendations

When comparing the four waste plastic treatment technologies, it is imperative to acknowledge the inherent limitations of each technology, stemming from their distinct raw material requirements. Each technology operates within its unique optimal conditions, with pyrolysis technology; for instance, imposing stringent specifications on plastic type, moisture content, and impurity levels. While these studies offer valuable insights into the potential environmental and economic benefits, it is crucial to recognize that their applicability is often constrained by the practical availability and quality of waste plastics encountered in real-world scenarios.

The limitations also involved a narrow focus on specific recycling technologies, the regional specificity of findings to Shanghai, and a lack of long-term sustainability analysis, including the durability of recycled products and the potential for technology obsolescence. The effectiveness of technologies was dependent on local policies and regulations, and practical challenges such as high initial costs and infrastructure needs were not fully explored. Furthermore, the economic feasibility of the recycling technologies was subject to market fluctuations, and it was essential to explore how these technologies handle variability in waste composition and integrate with existing waste management systems. Future research should focus on the advancement of technological and regional adaptation to assess long-term environmental and policy impacts. Practical challenges should be explored in the context of industry developments to develop robust and scalable waste plastics management strategies.

Conclusions

By classifying and summarizing the characteristics of the production and disposal of waste plastics in Shanghai, it is found that waste plastics mainly exist in two parts, including residual waste (88.4%) and recyclables (11.6%). Potential recycling pathways were summarized, revealing that 23% ± 1% of waste plastics in residual waste hold higher value for resource utilization. It was found that among these about 11% could undergo pyrolysis to generate oil, 4% could be recycled into plastic particles through recycling granulation, and 8% could be recycled into electricity through Green-RDF. Combining LCA and cost–benefit analysis, the corresponding resource processes were evaluated. Pyrolysis to oil had the best environmental benefits in GWP100, reaching -1,683.51 kgCO₂-eq, while recycling granulation had the best economic benefits, the net income of which would achieve 1,383 ± 35 yuan/ton. In terms of the critical elements of environmental benefits, the crucial element in the environmental benefits of recycling granulation was electrical consumption, while for the other three disposal technologies, the crucial element lied in the yield of substitute products. Moreover, when the substitute product yield increased by 3%, the environmental benefits of Green-RDF began to outperform recycling granulation technology. Ultimately, residual waste could reduce carbon emission by 29.74% via matching BATs.

Acknowledgements

The authors would like to thank all members of the Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery that contributing to the works, and all the companies that cooperated with the investigations.

Supporting information

The detailed information of on-site survey company; Typical contributing substances and their characterization values; Inventory data of material balance sheets for four different plastic waste treatment processes; Variations of domestic waste plastics production in Shanghai; Carbon emission from different resource utilization scenarios of waste plastics in residual waste from domestic sources in 2025; Detailed description of the grey prediction model; Carbon emission factor method.

Authors’ contributions

JYL: Writing- Reviewing and Editing, Investigation, Data Analysis, Diagramming, Supervision. HYJ: Writing, Methodology, Investigation, Data Analysis, Diagramming. QZ: Diagramming. CQ: Writing- Reviewing and Editing, Supervision. MP: Writing- Reviewing and Editing, Supervision. YZ: Investigation. ZJB: Investigation. WHC: Investigation. ZHY: Data Analysis, Diagramming. ZYL: Conceptualization, Writing- Reviewing and Editing, Supervision, Project administration, Funding acquisition.

Funding

This work was supported by the National Natural Science Foundation of China (42077111, 72261147460), the High-end Foreign Expert Introduction Program (G2022037007L) of China, Technology Innovation and Development Project of the Inner Mongolia Institute of Shanghai Jiao Tong University (2021PT0045-02–01), and the Jinan City Talent Development Project in 2021 (2021GXRC067).

Availability of data and materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Abbreviations

BAT

Best available technology

MSW

Municipal solid waste

LCA

Life cycle assessment

GWP100

Global warming potential with a 100-year horizon

CO₂-eq

CO₂ equivalent

GW

Greenhouse effect

POF

Photochemical ozone formation

AC

Acid deposition

NE

Eutrophication

ETs

Ecotoxicity (soil/air)

PP

Polypropylene

PE

Polyethylene

PS

Polystyrene

PET

Polyethylene Terephthalate

PVC

Polyvinylchloride

SI

Supporting Information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

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