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Resource Conservation
Q What is resource conservation and why is it important?

Through effective resource conservation, we can minimize our impact on the planet by using the earth's resources wisely. To do this, we must more efficiently manage natural resources and lessen the environmental impact of the products we use, from raw materials to production to distribution and on through ultimate disposal. In other words, you should strive to minimize the energy consumed and wastes generated during production, as well as through the life of a product and on to final disposition.


Q. What can I do to conserve resources?


In order to conserve resources, you must know about the resources utilized and the way in which they are consumed. Then decisions can be made based upon facts. Some simple actions include carpooling to work or taking public transportation, turning off lights in empty rooms, selecting the energy saver mode on your dishwasher, turning down thermostats at night during the winter and purchasing items with the most efficient packaging.



How do plastics contribute to effective resource conservation?


From production through use to waste management, plastics help conserve resources. Their unique properties and characteristics-light weight, durability, formability-enable manufacturers to minimize the raw materials used, energy consumed and waste generated in the production of goods ranging from automobiles to coffee cups. It's important to think about all those steps in a product's life cycle-not just what happens when a product's useful life is over-to get a true picture of its environmental performance.




How are plastics made?

A. Plastics consist of building blocks called hydrocarbons, typically derived from petroleum or natural gas. These monomers (small molecules) are bonded into chains called polymers or plastic resins. Different combinations of monomers yield resins with special properties and characteristics.



Why are plastics used in packaging?

A. Packaging serves many purposes, but one of its primary functions is to help protect the quality of goods -- ranging from sensitive electronics to fresh and prepared foods -- during shipping, handling and merchandising. Plastics are a versatile family of materials that are suitable for a wide range of packaging applications. In many cases, plastics offer the best protection while using minimal resources and creating less waste than alternative materials. In fact, 400 percent more material by weight would be needed to make packaging if there were no plastics, while the volume of packaging would more than double.



Why do we need different kinds of plastics?


Copper, silver and aluminum are all metals, yet each has unique properties. You wouldn't make a car out of silver or a beer can out of copper because the properties of these metals are not chemically or physically able to create the most effective final product. Likewise, while plastics are all related, each resin has attributes that make it best suited to a particular application. Plastics make this possible because as a material family they are so versatile.

Six resins account for nearly all of the plastics used in packaging:

PET (polyethylene terephthalate) is a clear, tough polymer with exceptional gas and moisture barrier properties. PET's ability to contain carbon dioxide (carbonation) makes it ideal for use in soft drink bottles.

HDPE (high density polyethylene) is used in milk, juice and water containers in order to take advantage of its excellent protective barrier properties. Its chemical resistance properties also make it well suited for items such as containers for household chemicals and detergents.

Vinyl (polyvinyl chloride, or PVC) provides excellent clarity, puncture resistance and cling. As a film, vinyl can breathe just the right amount, making it ideal for packaging fresh meats that require oxygen to ensure a bright red surface while maintaining an acceptable shelf life.

LDPE (low density polyethylene) offers clarity and flexibility. It is used to make bottles that require flexibility. To take advantage of its strength and toughness in film form, it is used to produce grocery bags and garbage bags, shrink and stretch film, and coating for milk cartons.

PP (polypropylene) has high tensile strength, making it ideal for use in caps and lids that have to hold tightly on to threaded openings. Because of its high melting point, polypropylene can be hot-filled with products designed to cool in bottles, including ketchup and syrup. It is also used for products that need to be incubated, such as yogurt.

PS (polystyrene), in its crystalline form, is a colorless plastic that can be clear and hard. It can also be foamed to provide exceptional insulation properties. Foamed or expanded polystyrene (EPS) is used for products such as meat trays, egg cartons and coffee cups. It is also used for packaging and protecting appliances, electronics and other sensitive products.



What about CFCs?

A. In response to concerns about the ozone layer, polystyrene manufacturers voluntarily phased out the use of chlorofluorocarbons (CFCs) in the late 1980s.



Why are plastics used in durable goods?

A. Manufactured items with a useful life of more than three years -- cars, appliances, computers, etc. -- are called durable goods. Manufacturers of durable goods choose plastics for many reasons: The automotive industry chooses plastic for its durability, corrosion resistance, ease of coloring and finishing, resiliency, energy efficiency and light weight. Lightweight, for instance, translates into lowered handling and transportation costs all down the line. Major appliance manufacturers use plastics because of their ease of fabrication and outstanding thermal insulation -- characteristics that significantly reduce energy consumption. The building and construction industry uses vinyl siding for homes because of its appearance, durability, ease of installation and energy efficiency. Plastics can reduce energy consumption for the auto, appliance, and building and construction industries, providing a substantial saving in production costs.


Energy Efficiency


Can plastics actually help save energy?


Yes. Only about 4 percent of the United States' energy consumption is actually used to produce plastic raw materials, including feedstocks. This is quite a small percentage in comparison to energy's other uses. In addition, it often takes less energy to convert plastics from a raw material into a finished product that comparable products.10,11 For instance:

During their life cycle, plastic bags require about one-third less energy to make than paper bags.*

Foam polystyrene containers take 30 percent less total energy to make than paperboard containers.

Fifty-three billion kilowatt hours of electricity are saved annually by improvements in major appliance energy efficiency made possible by plastic applications. Without the benefits provided by plastics insulation, these appliances would use up to 30 percent more energy.



How do plastics contribute to waste reduction?


Plastics are strong yet lightweight, meaning it often requires less plastic to make a certain package compared to other possible materials:

The plastic film wrappers now used for large diaper packs create 50 percent less waste by volume than previous packages.

Over 4 million students a day in the U.S. drink their milk or juice in flexible drink pouches. Compared to traditional cartons, the source-reduced pouch reduces weight by 80 percent and volume of waste by 70 percent, which reduces storage and trash disposal costs for schools.

Plastic grocery bags are lighter and create up to 80 percent less waste by volume than paper sacks. Normal economic market forces cause manufacturers to continually look for ways to reduce the cost of their packages by minimizing the amount of material used:

An average polystyrene foam plate today requires 25 percent less polystyrene to produce than it did in 1974.

Plastic grocery sacks were 2.3 mils (thousands of an inch) thick in 1976 and were down to 1.75 mils by 1984. In 1989, new technology gave us the same strength and durability in a bag only 0.7 mil thick. Along with weight and size reductions, plastics can contribute to waste reduction in other ways:

Plastics have an increased life span. Their physical properties allow them to be used in multiple applications, while their durability and flexibility allow them to be used again and again. For example, some laundry products are being packaged in reusable plastic bottles. Small packages of concentrated product are used to refill the original bottles, helping to reduce total packaging waste.

Plastics are lighter than many alternative materials. They have consistently reduced the weight of truck payloads and allowed companies to ship more product in fewer trucks. More than 2.8 million plastic grocery bags can be delivered in one truck. The same truck can hold only 500,000 paper grocery bags.16

Plastics generally exhibit superior resistance to breakage and denting. This results in fewer container breaches and less product loss on the packaging line, and safer handling in the the home.

Manufacturers of durable goods choose plastics for many reasons:

Plastics allow highly efficient manufacturing processes (up to 99 percent efficiency) that increase productivity by 20 to 30 percent and reduce capital expenditures by as much as 50 percent.

Without plastics' resistance to corrosion, the product life of some major appliances would be reduced by nearly 40 percent. By helping them last longer, plastics keep appliances and other durable goods out of the waste stream.



How does plastics recycling work?


Successful recovery of plastics -- like any material -- requires an infrastructure that can get plastics from the consumer and back into use as new products. The plastics recycling infrastructure has four parts:

Collection-Rather than being thrown away, plastics (primarily PETand HDPE) are collected for recycling. Curbside collection with other materials and drop-off at recycling centers are common plastics collection methods.

Handling-Plastics from collection programs are sorted to increase their value and compacted to reduce shipping costs.

Reclamation-In conventional recycling, sorted plastics are chopped, washed and converted into flakes or pellets that are then processed into new products. Advanced recycling technologies (see "What are advanced recycling technologies ?") can take mixed plastics back to their original building blocks (monomers or petroleum feedstocks). These can then be recycled into a number of different products, including new plastics.

End-use-Reclaimed plastic pellets or flakes-or petroleum feedstocks-are used to manufacture new products.



Why is sorting so important in plastics recycling?

A. There are different types of plastics, just as there are different types of metal, paper and glass. Steel and aluminum have to be separated before recycling, different colors of glass must be sorted and white office paper must be separated from newspapers and paperboard boxes. Each of the six common packaging plastics has performance characteristics that make it best suited for specific applications (see "Why do we need different kinds of plastics?"). Purchasers of recycled resins want to be sure that these properties are retained, so handlers sort plastics by resin type to command the highest market value.



What kinds of products are made with recycled plastics?


The variety of products made with recycled plastics is growing. Here are just a few examples:

Recycled PET can be used in producing deli and bakery trays, carpets, clothing and textiles.

Recycled HDPE can become bottles for laundry produ cts, recycling bins, agricultural pipe, bags, motor oil bottles, decking and marine pilings.

Recycled vinyl can become playground equipment, film and airbubble cushioning.

Recycled LDPE can be used to manufacture bags, shrink film and compost bins.

Recycled PP can be used in automobile parts, carpets, battery casings, textiles, industrial fibers and films used for packaging products such as candy.



Can plastic be recycled back into food contact applications?

A. Today, some recycled plastics are used in food and beverage containers. Technical and economic barriers currently limit widespread use of recycled plastic packaging in direct contact with food.



What are advanced recycling technologies?

A. The term advanced recycling describes a family of plastics recycling processes that yield a variety of versatile end products. Sometimes the term feedstock recycling or chemical recycling is used. These end products can be the building blocks from which plastics are made. By unlinking or unzipping plastics (polymers) to their original molecular components, recyclers can produce monomers or a petroleum product that can be made into monomers (the basic units from which plastics are made) or a number of other petroleum-based products. These developmental processes signal a significant technical breakthrough in plastics recycling technology because the products are identical to virgin feedstocks and monomers used to produce new plastics. Advanced recycling technologies are being researched to augment existing conventional mechanical systems as part of an integrated approach. They are designed to increase the volume of post-consumer plastics diverted from the waste stream and expand the variety of plastics that are recycled into new and useful products.




What happens inside a modern waste-to-energy facility?

A. The energy value of MSW can be recovered through waste-to-energy (WTE) incineration. Modern energy recovery facilities burn MSW in special combustion chambers, then use the resulting heat energy to generate steam or electricity. This process reduces the volume of MSW to be landfilled by as much as 90 percent. In 1997, there were 112 energy recovery facilities operating in 31 states throughout the United States with a designed capacity of nearly 101,500 tons per day.
Energy recovery facilities are designed to achieve high combustion temperatures that help MSW burn cleaner and create less ash for disposal. Modern air pollution control devices -- wet or dry scrubbers along with electrostatic precipitators or fabric filters -- are used to control and reduce potentially harmful particulates and gases from incinerator emissions.



Are plastics safe in waste-to-energy incineration?

A. Yes. Experts agree that properly equipped, operated and maintained facilities can meet the latest U.S. standards for air pollution control, among the toughest standards in the world. Plastics are a safe and valuable feedstock for these facilities.
Although some activists have suggested there is a link between certain plastics and increased dioxin emissions from w-t-e facilities, a blue-ribbon panel convened by the U.S. Conference of Mayors in 1989 found no evidence to support this claim. A 1995 report from the American Society of Mechanical Engineers reached the same conclusion.



How do plastics contribute to waste-to-energy incineration?

A. Plastics are typically derived from petroleum or natural gas giving them a stored energy value higher than any other material commonly found in the waste stream. In fact, plastics commonly used in packaging can generate twice as much energy as Wyoming coal and almost as much energy as fuel oil (see chart below). When plastics are processed in modern WTE facilities, they can help other wastes combust more completely, leaving less ash for disposal.

Energy Values
Btu / Pound
   • Polythlene
   • Polypropylene
   • Polystyrene
Corrugated Boxes (Paper)
Average of MSW
Yard Waste
Food Waste
Heat Content of common fuels
   • Fuel Oil
   • Wyorring Coal

4,500 to 4,800




Q. How do modern landfills protect the environment?
A. The purpose of solid waste management is to remove wastes from living areas in a way that protects human health and the environment. By sealing in wastes, well designed and well managed landfills control biodegradation and tend to preserve waste rather than compost it. Uncontrolled biodegradation could result in production of leachate that, if leaked, would endanger nearby groundwater supplies, lakes and streams. Many landfills include heavy-gauge plastic liners, which are required by the EPA, that help protect the groundwater from contamination.


Q. Can degradable plastics contribute to solid waste management?
A. In areas where composting or wastewater treatment is available as a solid waste disposal option, degradable plastics can effectively take advantage of these alternate disposal methods in some situations. Because modern landfills are apt to limit degradation, degradable materials of any type are not likely to affect the amount of landfill space available. Composting degradable plastics and paper waste with other organic compostable materials like yard, food and agricultural waste creates a valuable soil supplement and contributes to improved farming and gardening efficiency. Flushable, biodegradable products are readily treated in a regulated wastewater and sewage treatment facility, reducing the impact on other disposal systems.


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