Ohio State University Fact Sheet

Community Development

700 Ackerman Road, Columbus, OH 43202-1578

The Consumer's Role in Plastic Recycling

CDFS-114-98

Joe E. Heimlich, Ph.D.
Leader Environmental Sciences

The latest estimates of municipal solid waste show that plastic comprises by weight 8 percent of what goes into landfills. When translated into volume, this figure can escalate to as high as 20 percent of a household's waste.

Plastic is an oil - or natural gas-based product. This means that plastic is made from an energy source, and in addition requires energy to create. Plastic thus has a tremendous potential value for recapture. By recapturing plastic, we protect a fund (nonrenewable) resource and eliminate some of the problems in drilling for oil.

This fact sheet explores the consumer's role in plastics recycling.

What is Plastic Recycling?

As a petrochemical product, plastic does not revert to an original state in the remanufacture process. Plastic is collected, shredded, and pelletized, reprocessed and then formed into a new product. Because of contamination, plastics designed for food use, such as beverage or food containers, cannot be recycled into a product designed for food use. Further, in the recycling process, plastic resins should not be mixed if the properties of a specific resin are desired (high value plastic products).

Plastics are recycled by melting the material and creating pellets for reforming products through extrusion. In the process of melt recycling, the polymer chains that comprise the plastic are shortened. This creates a more rigid plastic with greater density. The recycled plastic, then has qualities different from the original plastic.

New markets and uses must be developed for recycling plastic. There are many new ideas on the market and many experiments for the utilization of recycled plastic. Plastic lumber, carpet fibers, building blocks and fiberfill are a few. Many more are needed.

As the current consumer demand increases, there will likely be an increased demand on industry to offer more recycled plastic products. The plastics industry is dedicated to the remanufacture process of plastics for two major reasons:

1) The recapture of the energy and material ultimately saves cost to the industry; and

2) The industry is very aware of its image regarding the environment.

Container Coding System

Once formed, by injection, extrusion, or molding, plastics are often indistinguishable. The same resin can take various forms. For example, there are clear plastic 2-liter pop bottles, clear plastic milk jugs, and clear plastic fruit drink containers all of which can be different resins. To aid both recyclers and consumers , the Plastic Bottle Institute instituted a bottle coding system in 1988. The codes were adapted by the Society of the Plastic Industry.

The code is a three-sided triangular arrow or a triangle with a number in the center of the triangle and letters underneath. The numbers and the letters indicate the plastic resin.

The code is molded into the bottom of bottles and jars that hold 16 ounces or more, and the other containers, (such as jars, tubs and trays) that hold 8 ounces or more.

Other plastics and non-identified plastic containers can be blended together in a mixed plastics recycling process.

The cost to the manufacturer is high in terms of both time and equipment conversion to change the bottle molds. The benefits in terms of the resin recapture and environmental considerations, however, are higher than the changeover cost and many companies have already adopted the practice of coding. Legislation in some states, including Ohio, requires such plastics coding.

The Codes

The current plastics coding system includes six identified plastic resins plus and "other" category. This system is outlined in Table 1.

The Consumer's Role in Plastic Recycling

Technologically, all plastic resins are recyclable, but recycling is limited by high processing costs and demand for the material. Local recycling centers accept various resins of plastics depending on local markets. If no market exists, a particular resin is not accepted for recycling and is therefore not useful to be separated.

The consumer role in recycling of plastics is to separate the various resins that are currently accepted by the local recycling program. Check with the local recycler regarding specific expectations and preparation of the materials, Some general guidelines are:

• Separate and caps, lids, or easily removable labels from the plastic prior to recycling.

• Rinse containers

• Triple-rinse containers that held cleansing products or hazardous materials.

Triple rinsing involves filling the container one-third with water, shaking vigorously for 30 seconds, and using the rinse water for the same purpose as the chemical product. This is repeated two more times. (Some recyclers may not accept hazardous material containers at all.)

• Separate unmarked plastic pieces from the pure resin product, if possible.

• Step on the bottle or container to reduce its volume before placing it in your recycling container.

Related Issues

There are many other factors that interact with recycling of plastics. Although they will not be dealt with here, it is good to note their existence.

Recyclability is relative to demand. Therefore, the high demand resins (PET, HDPE) are the most easily recycled. Plastics in incineration pose a potential threat due to the chlorinated compounds. The "degradability" of plastics is hotly debated concept. NO plastic is biodegradable, but the value of any degradable aspect of plastic products may pose a threat to recyclers.