360: Recycling Plastic Containers

Earth911’s 360 series breaks down the ins and outs of your everyday items.

When it comes to recycling plastic bags and plastic bottles, the process is pretty much black and white.

But we get into a gray area when talking about plastic containers (also known as rigid plastics or wide-mouth containers). What exactly are they? Why are they recycled differently?

It’s a tough subject, even for those who work in the industry. That empty peanut butter jar or that bottle of bleach is lumped into this category.

Considering the differences between these two containers, it’s obvious that the details of this “rigid plastic” label is complicated.

So, let’s break it down and take a detailed look at what items are classified as rigid plastics, how they’re made and how they’re recycled.

What They’re About

Starting off a bit formal, a rigid plastic is defined as “a formed or molded plastic container that serves as a package, and maintains its shape when empty and unsupported.”

Just to put into perspective how prevalent rigid plastics are, let’s take a look at our consumption. According to the American Chemistry Council (ACC), in 2007 an estimated 325.44 million pounds of non-bottle rigid plastics were collected for recycling in the U.S.

Many rigid containers are made from polyethylene (HDPE) and polypropylene (PP). This includes items such as HDPE tubs, PP cups and similar food containers. According to the ACC, the use of non-bottle rigid plastic containers and packaging has grown in leaps and bounds over the past decade.

Photo: made-in-china.com

Clamshell containers are often used for fresh produce or leftovers. This are classified as non-bottle rigid plastic containers. Photo: made-in-china.com

Some common items that are considered rigid plastic include:

  • Blister packs
  • Crates
  • Pallets
  • Carts
  • 5-gallon buckets
  • Clamshell containers
  • Plastic cups

Now, as more and more markets compete for the collected supply of these containers, some markets have begun processing non-bottle HDPE and PP containers to produce post-consumer resin for use in other products.

What’s in a Name?

Another barrier to understanding rigid plastics is the lack of clear definitions and specifications for different types of baled plastic. According to the ACC, this leads to a wide variety of quality and content in bales.

Note that not all containers or packaging will be accepted in your community program as types of resins differ. Furthermore, the random nature of the current collection and processing infrastructure in the U.S. is an obstacle to consistent supply of quality bales.

Just like other plastics, rigid plastics are broken down by resins. Forty-four percent of rigid plastics are made from HDPE, while 38 percent are PP. When rigid plastics are collected and sold, they are categorized into single and mixed resins. The most commonly requested mixed resins include:

Injection Plastic (Bulky Rigid Plastics)

Made primarily of Polyethylene (PE) and Polypropylene (PP), this type of mixed resin can be found in crates, carts, buckets, baskets and car bumpers.

Electronic Housings

This type of plastic container is primarily plastic HIPS-ABS-PC.

Commingled Bottles and Containers

This generally includes plastic #3-7 bottles and plastic #1-7 containers and/or all bottles and containers in some instances.

Mixed Rigid Plastics (#1-7s and #3-7s)

This plastic includes injection Polyethylene (PE) and Polypropylene (PP) mixed with plastic #3-7 bottles and plastic #1-7 containers.

Other Rigid Plastics

The ACC calls this the “catch all” category, defined on a case-by-case basis.

The tough part about recycling plastic containers is their different resins and quality of the bales. Photo: Naparecycling.com

The tough part about recycling plastic containers is their different resins and quality of the bales. Photo: Naparecycling.com

The 411 on Recycling

Over the last few decades, recycling has changed substantially. While solid waste generation has increased from 3.66 to 4.62 pounds per person per day between 1980 and 2007, the recycling rate has increased from 10 percent in 1980 to more than 33 percent in 2007.

According to the EPA, plastics accounted for 12.1 percent of the 254 million tons of municipal solid waste in 2007. Of that, only 6.8 percent was recycled.

More and more community programs are now accepting mixed rigid plastics, and the number is increasing steadily.

This is due to the demand from domestic and export buyers. In mid-2005, buyers placed a higher value on this material when virgin resin prices for polyethylene skyrocketed.

However, quality is not a high expectation when shipping overseas due to strong competition and lack of communication between converters and suppliers. According to the ACC, this is the fundamental reason why there is a wide variation of bales shipped overseas.

Some MRFs have tailored their sort operation to meet the domestic market specifications. In 2008, 28 of the 100 largest cities in the U.S. collected rigid plastics in their curbside programs. Predominately along the West Coast, of the 28 cities, 12 collect only all bottles and containers, and 16 collect rigid plastics beyond bottles and containers, such as toys.

What to Do With It

Okay, we’ll stop throwing around all this industry jargon and shoot it straight. So, you’ve got a bin full of plastic containers, what now? Let’s break it down.

  1. Determine what number of resin of your container. This will determine its specific material and its classification for recycling program. This number can usually be found on the bottom of the container.
  2. Check with your curbside program to see if this specific type of container is accepted.
  3. If you do not have curbside recycling or your program does not accept your material, check Earth911.com’s database for locations. We currently have 12,043 HDPE recycling locations across the U.S.

Feature image courtesy of Steven Depolo

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  1. I’ve heard many reasons why certain plastics are recycled and others made from the same resin are not accepted. It could be because some have extra additives, some have a different melting point and can’t be recycled together or even the difficulty of crushing certain plastics, which makes them easier to bale and transport.

  2. Recycling by melting is not the only option, over the past year I have been working on a wall of buckets. or better a bucket wall. If any can help collect buckets or has an idea of how to improve the wall please contact me. At present I have collected 4000 buckets with the project needing an additional 12000 buckets.
    The wall is located in Capitain NM email me for photos…David

  3. I would like to make ‘plastic bricks’ for an outdoor art project. The bricks would preferably be made with non recycleable plastic materials (not 1,2 or 3) I don’t believe a simple trash compactor would make the bricks solid enough. I would invoke the community to help collect for the project and could request specific grades of plastic – what grades/products would you recommend? A baler is a thought also … Any ideas ? ? ?

  4. I’m working in a Acrylic Stucco Manufacturer.We’re selling our stucco paint product in a 5 gal number2HDPE plastic container.Every year we sold about 75,000-100,000 pails of stucco product in 5 gal plastic pails.And this pails goes in to the contruction garbage bins.Any Idea how we can help our environment to recycle or to use other options for packaging acrylic stucco in an environmental friendly way.


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