How Our Recycling Systems Work

Paper cardboard recycling
Photo by Bas Emmen on Unsplash

“We get out of recycling systems what we put into them.” -Beth Porter1

Recycling is not the answer to all of our waste problems. Simply put, we’ve produced more plastic at this point than we could ever recycle away.

However, recycling can still be a part of the solution to protect ourselves and the planet, because we have to try. Ultimately we are responsible for the items and packaging from items we consume. Recycling, though far from a perfect solution, reduces the number of trees cut down for paper and the number of natural resources we harvest. Additionally, it curbs the production of new plastics and thus the fossil fuels we extract.

Green and white recycling truck on street, using a the lift to dump a residential recycling bin on a street.
Photo by the Brisbane City Council on Flickr, Creative Commons license(CC BY 2.0)

Single-Stream Recycling

“Ultimately, for recycling to become a way of life for consumers and end-users, recycling had to be easy, and it had to save money.”-Ryan Deer, Roadrunner Recycling, Inc.2

Single-stream simply means mixed materials in one group – one stream of materials. If your recycling goes in one bin and is picked up curbside, then you have single-stream recycling in your area.

The idea for single-stream came about in the 1990s because of two beliefs. First, that the convenience of putting everything in one bin would encourage more residents to participate in recycling. Using EPA statistics, one recycling company noted that single-stream recycling “overhauled the underperforming process, taking our national recycling rate from 10.1% in 1985 to 25.7% in 1995 to nearly 32% in 2005.”3

“Curbside recycling grew by 250 percent from 1988 to 1991…People were making the decision to incorporate sorting recyclable goods into their daily routine, reminiscent of war-era conservation efforts.” -Beth Porter4

The second belief is that single-stream recycling systems reduce collection costs. A single truck can collect more volume with mixed materials which reduces transportation costs. However, while collections costs are lower, the processing costs are much higher because of the sorting and separation, tasks which are performed by a combination of humans and expensive sorting machinery.

About 80% of U.S. communities use a single-stream recycling system. “Unfortunately, few could have predicted how low the ceilings really were, or how one move in global policy could send it all crashing down,” referring to China’s 2018 ban on many types of recycling imports.5 Single-stream is clearly riddled with problems and we must find a better way to handle recycling.

“More than 20 million tons of curbside recyclable materials are disposed [of] annually. Curbside recycling in the U.S. currently recovers only 32% of available recyclables in single-family homes, leaving enormous and immediate  opportunity for growth to support the economy, address climate change, and keep recyclable commodities out of landfills.”6

A bird's eye view of the interior of a Material Recovery Facility (MRF).
A bird’s eye view of the interior of a Material Recovery Facility (MRF). Photo by Urban Greendom on Flickr, Creative Commons license, (CC BY-NC-ND 2.0).

Material Recovery Facility (MRF)

Recycling collected through single-stream is taken to a Material Recovery Facility, or MRF (pronounced”murf”), and sorted by type of material for them to sell. That is the entire purpose of a MRF: the recycling trucks deposit the collected materials, and the MRF sorts, separates, removes waste from, and bales the recycling together. MRFs are businesses seeking profit; they are not municipally owned and operated.

The physical processing at MRFs varies. But a series of expensive, interconnected machines largely sorts the materials. We produce so much waste that there is no other way to separate it. In 2018, the U.S. produced 292.4 million tons of waste, and we recycled approximately 69 million tons.7 That’s not enough.

Generally, at the MRF, trucks dump the mixed materials onto a large floor, called the tipping floor. A front-end loader drops it into a large bin, called a drum feeder, at the start of the processing line. The materials move through a series of conveyor belts with fans, magnets, and wheels to separate the types of items. Humans remove debris and non-recyclable items at various points to prevent tangling or damage to the machinery. Small items, such as caps and utensils, are not likely to make it through these systems because of their size. In addition, they are difficult to bale because they do not have much surface area. For a video of how MRFs work, see Additional Resources below.

At the end of this process, the MRF bales the recyclables to sell to recyclers and manufacturers. The markets change constantly so one of the biggest challenges is recouping money from the materials. Remember, the MRF is looking to profit just like any other business. Recycling does not happen unless it is profitable.

Worker looking at bales of recycling at a recycling center.
Photo by Vivianne Lemay on Unsplash

Increased Contamination

Contamination is simply the mixing of recyclables with dirty items and non-recyclables. The average resident may not want to spend time cleaning their recyclables, or they may not know it is necessary. They may not understand what is and is not accepted in their local recycling. They may also be “wish-cycling,” which is when someone attempts to recycle something they think should be recycled, like a plastic bag, but which is not recyclable. That plastic bag can get tangled in the machinery at the MRF, and it contaminates the end product of recyclables the MRF needs to sell. If the recyclables have too many contaminates, or non-recyclable items, those bales are likely to be landfilled or incinerated rather than sold to a company that will reuse them.

“When consumers put non-recyclable items into their recycling bins, those materials take a long and circuitous (and expensive) route to the landfill.” -Jennie Romer8

Contamination rates more than doubled between 2007 and 2013.9 “Because of how the system works, the ‘magic bin’ is actually a disgusting, contaminated soup pot. Shaken, stirred, and dumped into a compactor truck with your neighbors’ random mix, contamination keeps 25% of what we put in our recycling bin from ever being processed at a MRF,” wrote Ryan Deer.10 Reducing contamination is key, but it is difficult within a single-stream recycling system.

“For nearly 30 years, Americans have been honeymooning with a recycling system that seems too good to be true.” -Ryan Deer, Roadrunner Recycling, Inc.11

Paper recycling bale, contaminated with a blue plastic Finesse shampoo bottle.
Paper recycling bale, contaminated with a plastic shampoo bottle. Photo by Vivianne Lemay on Unsplash

Dual-Stream Recycling

In a dual-stream system, each material type is kept in a separate bag or bin, and trucks have three or more compartments. The materials are already sorted upon arrival at the MRF. This was the common recycling collection system until single-stream became the dominant system by the mid-1990s. It costs more and requires trucks with separate sections. But the higher costs “of having residents sort could very well be offset by the higher-quality materials they’re recovering and able to sell.” Single-stream loses about 25% of collected materials from contaminants versus less than 12% in dual-stream.1213

Essentially, most recycling centers serve as a dual-stream system because residents separate the recycling into different dumpsters, which the recycling company collects directly. This results in lower contamination and higher recovery rates, meaning less of that recycling is landfilled.

“There is significant evidence that the resulting scrap material quality (and hence the revenue) is lower under single-stream collection than it is under a dual stream system or under systems like container deposits, where materials are kept separate.” -The Container Recycling Institute14

Collected PET plastic bottles crushed.
Photo by tanvi sharma on Unsplash

System-Wide Problems

Although consumers need to do their part, the problems with recycling in the U.S. do not fall solely on the public. In fact, the systems in place are themselves faulty. Packaging and single-use disposable production are out of control, and the market demand is low. The market needs improvement, as the cost for new materials is sometimes lower than recycled materials. Additionally, only between 50-74% of Americans have access to curbside recycling. There are multiple problems. But that doesn’t mean it can’t change. As The Recycling Partnership noted:

“The ultimate fate of recyclable materials rests in the hands of a broad set of stakeholders who must all do something new and different to support a transition to a circular economy. Strong, coordinated action is needed in areas ranging from package design, capital investments, scaled adoption of best management practices, policy interventions, and consumer engagement.15

How To Recycle Better

While recycling systems must be improved and we must find or create demand for recycled materials, we can help improve our own practices. Remember, that just because a product is made with recycled materials, does not necessarily mean it is recyclable. “A 2016 survey showed that 59 percent of the public thinks that ‘most types of items’ are recyclable in their town, perhaps without knowing the local rules,” wrote Beth Porter.16 You can find a list of what is acceptable in your area by going to your municipal website.

Here’s how you can help improve single-stream and dual-stream recycling to keep from contaminating the recycling:

      • Don’t put in plastic bags or films. (Note: Supermarkets often collect bags.)
      • Do not bag your recyclables.
      • Empty and rinse the containers. Food contamination, especially as it rots, reduces the value of the recyclables.
      • Don’t crush plastic recyclables. This is so that the MRF can read the resin codes (plastic #) on the bottom of the containers.
      • Separate the caps and only recycle them if they have a proper resin code that is accepted in your area. Most of the time, you will be throwing these away.
      • Do not recycle candy wrappers, paper cups, receipts, plastic straws and utensils, polystyrene or Styrofoam, shredded paper, complex cartons (milk cartons, broth, soup, etc.), large plastic items (chairs, laundry baskets, etc), electronics, or batteries.
      • Certain types of glass cannot be recycled: window, mirror, crystal, or Pyrex.
      • Do not put in take-out containers, especially foam ones, unless they are plastic #1 or #2 and are clean.
      • Pizza boxes depend on your area, but most of the time the grease on the cardboard contaminates recycling. You can tear off the bottom and recycle the top if it is free of grease and food.
      • Remove shrinkwraps from #1 and #2 bottles.
      • Frozen food boxes are usually not recyclable because they contain a layer of plastic coating (to protect the package from moisture).
      • Flatten cardboard boxes.
      • Other items that you should put in the garbage, and not the recycling, include applesauce/juice packets, milk or broth cartons (or any multi-layer packaging), and paper napkins/towels.

Some of the items listed above are accepted through separate recycling streams. Elizabeth Royte wrote, “A common motto is ‘When in doubt, throw it out,’ but I prefer the alternative ‘When in doubt, go find out’ to build better habits rather than giving up on confusing items.”17 Do your best and teach others how to recycle better as well.

The bottom line is, if we purchase something, we need to take responsibility for disposing of it. If we stop buying so many products in single-use disposable containers, especially plastics, the companies and manufacturers will stop producing them as demand goes down. At the same time, companies must take real initiative and stop producing waste that is not recyclable.

Graphic of a tree with the leaves in the shape of a recycling symbol. Blue sky background.
Image by 政徳 吉田 from Pixabay

Going Forward

“If all of the 37.4 million tons of single-family recyclables were put back to productive use instead of lost to disposal, it would reduce U.S. greenhouse gas emissions by 96 million metric tons of carbon dioxide equivalent, conserve an annual energy equivalent of 154 million barrels of oil, and achieve the  equivalent of taking more than 20 million cars off U.S. highways.”18

We have the opportunity to make a real difference by better handling our waste. While recycling is not the answer to our waste problems, it is still very important. We need a coordinated effort to reduce waste, to increase demand and markets for recycling, and to be better stewards of the waste we do create. The Recycling Partnership lists these strategies in order to overhaul and improve our recycling systems:

    • “Substantially greater support of community recycling programs with capital funding, technical assistance, and efforts to strengthen and grow local political commitment to recycling services.
    • Development of new and enhanced state and federal recycling policies.
    • Continued and expanded investment in domestic material processing and end markets.
    • Citizen and consumer engagement to create and sustain robust and appropriate recycling behavior.
    • Continued innovation in the collection, sorting and general recyclability of materials, including the building of flexibility and resiliency to add new materials into the system.
    • Broader stakeholder engagement in achieving all elements of true circularity, in which the fate of all materials is not just intended to be recycled, but that they are designed, collected, and actually turned into something new.”19

In the end, we need to focus on reducing waste, including “recyclables,” in order to turn the tide of excessive waste. We must stop wishing for easy and convenient solutions and instead take responsibility for our waste.

Will we do it? What are your ideas? Feel free to leave me a comment below. Thank you for reading, please share and subscribe!

 

Additional Resources:

Video, “How Recycling Works,” SciShow, June 11, 2015. I love how succinctly this video breaks down how recycling works at the MRF. You’ll learn a lot in just 8 minutes!

Article, “What is a Materials Recovery Facility (MRF)?,” by Shelby Bell,

Video, “Single Stream Recycling – Tour a Material Recovery Facility (MRF),” Van Dyk Recycling Solutions, October 13, 2016.

Video, “Ever Wonder Where Your Recyclables Go? Get an Inside Look at Where the Magic Happens,” about the Sims Municipal Recycling facility in New York City, featured by Mashable Deals on youtube, May 29, 2018.

Article, “These Items Don’t Belong in Your Recycling,” by Ryan Deer,

Article, “The Violent Afterlife of a Recycled Plastic Bottle: What happens after you toss it into the bin?” by Debra Winter, The Atlantic, December 4, 2015.

Article, “Recycling in the U.S. Is Broken. How Do We Fix It?” by Renee Cho, Columbia Climate School, March 13, 2020.

Footnotes:

  1. Book, “Reduce, Reuse, Reimagine: Sorting Out the Recycling System,” by Beth Porter, Rowman & Littlefield: Lanham, 2018.
  2. Article, “Why U.S. Cities Are Ending Single-Stream Recycling,” by Ryan Deer, Roadrunner Recycling, Inc., July 8, 2021.
  3. Article, “Why U.S. Cities Are Ending Single-Stream Recycling,” by Ryan Deer, Roadrunner Recycling, Inc., July 8, 2021.
  4. Book, “Reduce, Reuse, Reimagine: Sorting Out the Recycling System,” by Beth Porter, Rowman & Littlefield: Lanham, 2018.
  5. Article, “Why U.S. Cities Are Ending Single-Stream Recycling,” by Ryan Deer, Roadrunner Recycling, Inc., July 8, 2021.
  6. Report, “2020 State of Curbside Recycling Report,” The Recycling Partnership, February 13, 2020.
  7. Page, “National Overview: Facts and Figures on Materials, Wastes and Recycling,” Environmental Protection Agency, accessed August 11, 2021.
  8. Book, Can I Recycle This?: A Guide to Better Recycling and How to Reduce Single-Use Plastics, by Jennie Romer, Penguin Books, New York, 2021.
  9. Book, Bottlemania: Big Business, Local Springs, and the Battle Over America’s Drinking Water, by Elizabeth Royte, Bloomsbury: New York, 2008.
  10. Article, “Why U.S. Cities Are Ending Single-Stream Recycling,” by Ryan Deer, Roadrunner Recycling, Inc., July 8, 2021.
  11. Article, “Why U.S. Cities Are Ending Single-Stream Recycling,” by Ryan Deer, Roadrunner Recycling, Inc., July 8, 2021.
  12. Book, Bottlemania: Big Business, Local Springs, and the Battle Over America’s Drinking Water, by Elizabeth Royte, Bloomsbury: New York, 2008.
  13. Page, “Single Stream Recycling,” The Container Recycling Institute, accessed August 1, 2021.
  14. Page, “Single Stream Recycling,” The Container Recycling Institute, accessed August 1, 2021.
  15. Report, “2020 State of Curbside Recycling Report,” The Recycling Partnership, February 13, 2020.
  16. Book, “Reduce, Reuse, Reimagine: Sorting Out the Recycling System,” by Beth Porter, Rowman & Littlefield: Lanham, 2018.
  17. Book, Bottlemania: Big Business, Local Springs, and the Battle Over America’s Drinking Water, by Elizabeth Royte, Bloomsbury: New York, 2008.
  18. Report, “2020 State of Curbside Recycling Report,” The Recycling Partnership, February 13, 2020.
  19. Report, “2020 State of Curbside Recycling Report,” The Recycling Partnership, February 13, 2020.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.