High-density polyethylene (HDPE) resin is produced from the chemical compound ethylene. HDPE bottles are blow-molded. Bottles are used for milk and other liquid products, detergents, shampoos, motor oil, drugs, and cosmetic products. Most milk and water bottles use a natural-colored HDPE resin. Bottles used for other products often have colorants added to the resin.
Injection-molded HPDE containers are used for products such as margarine and yogurt. More HDPE bottles are produced than containers. HDPE resin can also be used to make bottle and container caps and flexible packaging such as sacks and trash bags. HDPE is also used in many non-packaging products.
Bottles and containers comprise 64 percent of HDPE packaging products. Bottles and containers are 41 percent of all HDPE products. HDPE bottles and containers began displacing heavier metal, glass and paper packages in the ’70s. Although the amount of HDPE used in bottles and containers has tripled since 1980, its garbage market share is still less than 1 percent. All HDPE products have a garbage market share of 2.2 percent.
This profile only covers HDPE bottles and containers.
Chaz Miller is state programs director for the National Solid Wastes Management Association, Washington. E-mail him at: [email protected]
HDPE Bottles & Containers Facts*
- 2.25 million tons, or 0.8% of municpal solid waste (MSW) by weight.
- 0.8 million tons of milk and water bottles.
- 1.25 million tons of containers for other products.
- 14.54 pounds (lbs.) per person per year.
- 500,000 tons, or a 22% recycling rate.
- 468,000 tons, or 29%, based on industry data.
- 220,000 tons of milk and water bottles, or a 27.5% recycling rate.
- 280,000 tons of other bottles, or a 19.3% recycling rate.
- #2 in the plastic resin code.
- Varies by end product but increasingly common in non-food containers
Incinerated or Landfilled:
- 1.75 million tons, or 1.06% of discarded MSW by weight.
- Highly combustible with 18,690 BTUs per pound, more than three times MSW.
- Not biodegradable in landfills.
- 6.3 million cubic yards, or 1.5% of landfilled MSW in 1997.
- Landfilled milk jugs weigh 355 pounds per cubic yard (lbs./cu.yd.)
- Loose milk jugs weigh 24 lbs./cu.yd.
- Flattened milk jugs weigh 65 lbs./cu.yd.
- Loose, colored HDPE bottles weigh 45 lbs./cu.yd.
- Bales of HDPE generally weigh 500 - 800 lbs.
- “Concentrated” detergents use less HDPE than “unconcentrated” products.
- An empty 1-gallon milk jug weighs less than 60 grams. In 1970, it weighed 95 grams.
- Non-food bottles, exports, drainage pipe, plastic lumber and other markets.
End Market Specifications:
- ISRI Scrap Specifications Circular 2012: Baled HDPE Mixed Colored Bottles, Baled HDPE Natural Bottles and Mixed Unsorted 1-7 Bottles and Containers.
- The specs allow 2% contamination and no free liquids.
- Injection-molded containers often incompatible with blow-molded bottles in reprocessing operations.
American Plastics Council, Washington, www. plasticsresource.org
“Measurement Standards and Reporting Guidelines,” National Recyling Coalition, Washington, www.nrc-recycle.org
“Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2010,” U.S. EPA, Office of Solid Waste, www.epa.gov/osw
“Scrap Specifications Circular 2008,” Institute of Scrap Recycling Industries, Washington, www.isri.org
*Data is from 2010 EPA estimates, except where noted.