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We Need to Modernize Mixed Plastic Recycling

January 18, 2024

mixed recycling

Fifty-plus years since the first plastic recycling facility opened its doors in Conshohocken, Pennsylvania and the United States is still only recycling approximately 5% of plastic, according to a report from Greenpeace. The global numbers are nominally better–9% according to The Economist. But with production of new plastic soaring–459 million tons in 2019 compared to 51 million tons in 1973– these levels are not going to solve the problem. There needs to be new thinking to modernize the way we recycle. 

A big part of the problem is that different kinds of plastics have different recycling needs. From the ordinary soda bottle (PET) to laundry detergent containers (HDPE) to PVC pipes and beyond, the seven kinds of plastic identification codes each require their own recycling systems. The term “mixed plastics” refers to a combination of these different plastic types, making their recycling process complex and costly.

While plastic has been part of the landscape for nearly 200 years, it was not until the end of the second World War that its use really took off. Suddenly plastics were used in virtually every product imaginable from household products like dishes and cups to furniture and automotive components.

However, plastics have pretty much been a one-way path from manufacturer to landfill. Efforts to recycle them have done little to stem the growing surge of plastic waste. Plastic waste that ends up in a landfill effectively stays there forever because plastics don’t decompose in the traditional, organic sense.

Instead, plastic breaks down into smaller and smaller pieces until it becomes known as microplastic. Measuring less than 5 millimeters in length (about the size of a seed and smaller), these tiny globules of plastic have been found in every corner of the earth, from deep ocean trenches to the heights of mountaintops.

And there is no let-up in sight. Plastics production has increased substantially nearly every year since 1950. With more plastic pouring out of manufacturers every day and no path in place to get rid of what already exists, our unsustainable dependence on plastic has led to a mounting environmental crisis. In order to address this issue, it is crucial to modernize mixed plastic recycling and embrace sustainable materials management practices.

Plastic and the World's Unsustainable Dependence on It

While sources don’t all agree on the amount of plastic that is currently being recycled, they all agree that the numbers are not good. The Organisation for Economic Co-operation and Development (OECD) reports that only 9% of plastic produced worldwide gets recycled.

The world's dependence on plastic has reached unsustainable levels. The production and consumption of plastic have surged exponentially over the past few decades, resulting in severe environmental consequences. One of the main issues lies in the inherent nature of plastic. It is designed to be durable and long-lasting, which makes it highly resistant to natural degradation processes. As a result, plastic waste persists in the environment for hundreds of years, causing significant harm to ecosystems and wildlife.

And it’s not just the existence of plastic that’s the problem. The extraction of fossil fuels, which serves as the raw material for plastic production, contributes to greenhouse gas emissions and climate change. Moreover, the manufacturing process itself requires significant amounts of energy, further exacerbating the environmental footprint of plastic.

Disposal of plastic waste poses a monumental challenge. Despite recycling efforts, a considerable portion of plastic ends up in landfills or is improperly discarded, ultimately finding its way into water bodies, polluting oceans and harming marine life.

Addressing the unsustainable dependence on plastic requires a multifaceted approach. It involves reducing the production and consumption of single-use plastics, promoting alternatives and sustainable materials, improving waste management systems, and enhancing recycling technologies. Efforts are being made to ban certain types of single-use plastics, encourage reusable alternatives, and promote a shift towards a circular economy model that emphasizes waste reduction, recycling, and reuse.

Trying to Solve the Issue with Plastic Recycling: Successes and Failures

Plastic recycling has been widely regarded as a potential solution to mitigate the environmental impact of plastic waste. While there have been notable successes in certain aspects of plastic recycling, there have also been significant challenges and failures that need to be addressed. 

  • Polyethylene Terephthalate (PET) Bottle Recycling:
    One of the notable success stories in plastic recycling is the recycling of PET bottles. PET bottles are widely collected and recycled, primarily due to their high market demand as a raw material for new products. This success can be attributed to effective collection systems, consumer awareness campaigns, and the existence of a well-established recycling infrastructure.

    As a result, the recycling rate for PET bottles has been relatively high in many regions, contributing to resource conservation and waste reduction. For instance, countries like Germany, Norway, and Sweden have achieved recycling rates above 90% for PET bottles. Things haven’t fared so well in developing countries and countries with weak waste management infrastructure. Limited access to recycling facilities, insufficient collection mechanisms, and challenges in raising public awareness and participation can hamper recycling efforts.

  • Deposit-Refund Systems:
    Deposit-refund systems have proven successful in boosting recycling rates for certain types of plastic containers, particularly beverage containers. These systems encourage consumers to return their empty containers to designated collection points in exchange for a refund. This initiative has been effective in countries such as Germany, Sweden, and South Australia, where high recycling rates for beverage containers have been achieved. The success of deposit-refund systems lies in their ability to incentivize consumers and establish a closed-loop recycling process.

  • Plastic Bag Bans and Fees:
    Another notable success in plastic recycling efforts is the implementation of plastic bag bans or fees. By discouraging the use of single-use plastic bags, many regions have witnessed a significant reduction in plastic bag consumption. This reduction translates into less plastic waste being generated and fewer bags ending up in landfills or polluting the environment. California’s ban on plastic bags has reportedly reduced consumption by over 70%. Countries like Ireland, Bangladesh, and Rwanda have successfully implemented plastic bag bans, resulting in significant positive environmental outcomes.

Despite these successes, the recycling of mixed plastics remains a major challenge.

Mixed plastic recycling efforts are hindered by contamination and inadequate sorting. For mixed plastic to be recycled efficiently, it needs to be sorted into different plastic types. When plastic types are mixed or contain non-recyclable materials, it is considered contaminated, and the quality and value of the recycled plastic is negatively impacted. Contaminated plastics must be sorted before they can be recycled. But insufficient sorting infrastructure and processes make it challenging to separate different plastic types effectively.

Advanced sorting technologies, such as optical sorting systems, exist and can help automate the process and improve efficiency, but the systems are expensive. These issues affect the overall success of plastic recycling and require improvements in recycling technology and education.

While successes have been achieved in specific areas of plastic recycling, such as PET bottle recycling and deposit-refund systems, challenges persist. The recycling of mixed plastics, contamination, and inadequate sorting remain significant hurdles that need to be addressed. To improve plastic recycling rates and outcomes, it is essential to invest in advanced sorting technologies, enhance education and awareness about proper recycling practices, and develop innovative solutions for recycling mixed plastics.

Plastic Recycling's Failures and Impacts

Plastic recycling, despite its potential environmental benefits, has encountered significant headwinds. While recycling efforts aim to divert plastic waste from landfills and reduce resource consumption, various challenges have hindered its effectiveness.

  1. Low Recycling Rates: One of the key failures in plastic recycling is the low recycling rates globally. The recycling rates for plastics, especially mixed plastics, remain low. The OECD reports that the global recycling figure is 9%. This failure can be attributed to several factors, including inadequate recycling infrastructure, limited consumer awareness, and the lack of harmonized recycling systems. As a result, a significant portion of plastic waste ends up in landfills, contributing to environmental pollution and resource depletion.

  2. Limited Market Demand: While there are success stories for specific plastic types, such as PET bottles, many other types of plastics face challenges in finding viable end markets. The lack of demand for recycled plastics hinders the economic viability of recycling initiatives and undermines efforts to close the loop in the plastic lifecycle. This failure results in recyclable plastics being downcycled or incinerated, rather than being effectively recycled.

  3. Contamination and Quality Issues: Plastic recycling faces contamination and quality issues, impacting its overall effectiveness. Contaminated plastics are challenging to process, reducing their quality and market value. These issues undermine the entire plastic recycling process and lead to inefficiencies in the overall process.

  4. Ineffective Sorting and Collection Systems: Sorting and collection systems pose significant challenges in plastic recycling. Inadequate sorting infrastructure and processes make it difficult to separate different plastic types effectively. This leads to inaccurate recycling rates and contamination issues. Inefficient collection systems, such as inadequate recycling bins and inconsistent collection practices, also hinder recycling efforts. The failure to establish robust and efficient sorting and collection systems limits the quantity and quality of recyclable plastics that can be effectively processed.

  5. Lack of Standardization and Global Coordination: The absence of standardized recycling symbols, labeling, and recycling processes globally contributes to the failures in plastic recycling. Inconsistent practices and confusion surrounding recycling guidelines lead to improper disposal and ineffective recycling. The lack of global coordination hampers efforts to create a cohesive and efficient recycling system that can maximize the recovery of plastic waste.

The failures in plastic recycling have significant negative impacts on the world. Plastic waste that is not properly recycled accumulates in landfills, polluting the environment and posing hazards to wildlife. The energy-intensive production of virgin plastic exacerbates greenhouse gas emissions and contributes to climate change. The reliance on fossil fuels for plastic production further depletes natural resources and perpetuates our unsustainable dependence on non-renewable materials.

To address these failures and mitigate their impacts, investments in recycling infrastructure, advanced sorting technologies, and standardized recycling practices are essential. Additionally, educating the public about proper recycling practices and raising awareness about the importance of creating demand for recycled plastics can help overcome some of the challenges faced by plastic recycling. Only through concerted efforts can we establish a more effective and sustainable plastic recycling system that minimizes environmental harm and promotes resource conservation.

Social and Technical Challenges: Misinformation and Aging Systems

Lack of education has impaired the public’s awareness of plastic recycling. While skepticism is an important tool in questioning, and in turn, reexamining and improving dated systems, being able to decipher recycling facts from fiction will be instrumental in fighting the domino effects of misinformation: improper sorting and disposal practices, contaminated recycling streams, and diminished quality of recycled plastic.

The solution to ensure proper recycling is utilized and its merits are common knowledge? A concerted and coordinated effort deploying a consistent message needs to be undertaken to not only combat misinformation but also to educate people on the virtues of plastic recycling.

Local and state governments need to lend support and funding to create education initiatives such as community workshops, school programs, and online resources to educate individuals on recycling practices specific to their localities. Accurate and accessible recycling education campaigns need to be disseminated to provide clear guidelines on proper sorting, recycling symbols, and accepted materials can empower individuals to make informed decisions and participate effectively in recycling efforts.

On the systems front, procedural mechanisms that were once state-of-the-art, are now aged. Recycling technology has seen many advances, but the cost and disruption has put the main market for this new technology – plastics recyclers – out of reach.

Not only are many of these systems antiquated from a technological perspective, but they also suffer from a logistical shortcoming: the current systems were designed for a different era and can scarcely handle the ever-increasing volume of plastic waste.

Advancements in recycling technology are crucial for improving the efficiency and effectiveness of plastic recycling. AMP Robotics founder Matanya Horowitz told Forbes that the challenges with recycling lie in the reduction of sorting costs or in increasing the material value, two areas where AI and machine-learning can lend a hand.  

Chemical recycling technologies are also being developed to break down plastic waste into its original components for reuse. Furthermore, innovative processes such as depolymerization show promise in transforming plastic waste into valuable products at lower heat—and thus less costly.

One such advancement published in the October 2022 issue of the Journal of the American Chemical Society uses a chemical process to recycle the two most-used plastics—polyethylene (PE) and polypropylene (PP)—into propane. The promising development is still being researched but will require some wholesale changes among plastics recyclers.

By investing in research and development of recycling technologies, we can overcome the challenges associated with mixed plastics and increase the quality and quantity of recycled materials.

Outdated equipment, inefficient processes, and inadequate sorting technologies hinder the recycling of mixed plastics and reduce the quality of recycled materials. Additionally, the lack of standardization in recycling practices and inconsistent collection methods further undermine the effectiveness of recycling efforts.

The Role of EPR and Intelligent Product Design in Solving Mixed Plastic Recycling Problems

Extended Producer Responsibility (EPR) and intelligent product design have emerged as crucial strategies in addressing the challenges of mixed plastic recycling. By incorporating these approaches, we can promote sustainability throughout the lifecycle of plastic products and improve recycling outcomes.

EPR is a policy framework that places the responsibility of managing waste on the producers of the products. It shifts the burden away from consumers and local governments, holding manufacturers accountable for the environmental impact of their products throughout their entire lifecycle, including disposal and recycling. Incentives are provided to producers to adopt sustainable practices by imposing financial and operational obligations. EPR encourages manufacturers to design products that are easier to recycle and ensures their participation in establishing effective recycling infrastructure. By making producers responsible for the end-of-life management of their products, EPR can drive improvements in the recycling and recovery of mixed plastics.

In Germany, the plastic waste problem doubled in the past two decades. Deploying EPR tactics, Germany created a tiered system starting with reducing waste by minimizing production of it at the manufacturing level, product end-of-life returns, and the ability for consumers to return the packaging of the goods they by to the manufacturer. In the twenty years since Germany began deploying their EPR strategies, the recycling rate has jumped from 53% to over 94%. Virtually all of all packaging placed on the German market was collected for recycling, and over 71% of this packaging was recycled.

Intelligent product design is another front on which the war on plastic waste can be fought. The idea behind intelligent product design is that products and packaging can be designed with sustainability in mind. Part of the goal is to achieve “circularity,” that is, a product made of materials that can be reused. It means making considerations for an uncontaminated recycling stream by using only one kind of plastic, making products that can easily be disassembled, and making products that can be reused. While these may seem like simple steps, they represent an about-face for much of industry who have designed much of their wares with planned obsolescence in mind.


The Power of Waste Generation Perception and Reduction

While recycling is an important component of waste management, it has limitations and challenges. Recycling processes require energy, resources, and specialized infrastructure, and not all materials can be effectively recycled. Additionally, there is often a loss in material quality and value during the recycling process.

The focus and value of waste reduction and reuse is to prevent waste in the first place, reducing the need for recycling altogether. Reduction and reuse require virtually no infrastructure or technology to see benefit and have positive environmental impacts. Since there is little-to-no manufacturing involved in reduction and reuse, it creates no additional greenhouse gases.

By adopting practices such as mindful consumption, conscious purchasing, and choosing durable and long-lasting products, as well as repairing and repurposing, waste output can be reduced on an individual basis. This includes reducing excessive packaging, avoiding single-use items, and opting for eco-friendly alternatives. By reducing waste at its source, the practice of waste reduction minimizes the environmental impact associated with its disposal and promotes a more sustainable lifestyle.

Recycling is often highlighted as an essential solution, but the concepts of reduction and reuse have a more significant and lasting impact on mitigating the environmental consequences of waste. Still, some wastes are simply unavoidable. It’s why working with a sustainability partner to manage those waste streams can be so beneficial.

By utilizing resources that allow us to take a closer, more holistic look at our operations and their waste streams, we can more effectively prioritize waste reduction and reuse, and when necessary, recycle in ways that don’t just remove risks, but find synergies to create value. These end-to-end approaches conserve resources, reduce energy consumption, minimize pollution, and help combat climate change to a greater extent. They also promote a shift towards a circular economy, where resources are used more efficiently, waste generation is minimized, and material outputs are used as inputs to other production systems or revenue streams.

This method of closed-loop materials management, in conjunction with the aforementioned imperatives is essential to modernizing mixed plastic recycling, addressing society’s unsustainable dependence on plastic, and mitigating plastic’s significant environmental impacts. By embracing forward-looking sustainable materials management practices, EPR, and intelligent product design, and improving recycling education, rhetoric, and technology, we can overcome the challenges associated with mixed plastic recycling. However, a paradigm shift in waste generation perception and a focus on waste reduction, reuse, and value-creation-based recycling will ultimately have the greatest positive impact in creating a sustainable world.

Ultimately, tackling today’s unsustainable dependence on plastic requires a collective effort from governments, industries, and individuals. It calls for conscious and conscientious consumption choices, innovative solutions, and policy interventions that prioritize the preservation of the environment and the well-being of generations to come.

Only through concerted action can we overcome the challenges posed by plastic and forge a path towards a more sustainable and responsible future.

For more on recycling and the powerful, value-creation solutions that can support it, talk to a sustainability expert.


A major source of net carbon negative energy

8 acquisitions
For each ton of waste we recover for energy, Covanta saves 1 ton of CO2 equivalents (CO2e). In 2022, we avoided 19 million metric tons of CO2e.

A major source of net carbon negative energy

8 acquisitions
For each ton of waste we recover for energy, Covanta saves 1 ton of CO2 equivalents (CO2e). In 2022, we avoided 19 million metric tons of CO2e.

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