Recycling Plastics

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Recycling Plastics
Waste Policy

May 7th, 2005

Matthew Kirchoffner

I. Introduction
Recycling is a hot issue in today’s society and one that has gradually gained momentum over the years as wastes and threats to the environment and human health have grown. As technology develops, the amount of materials that can be reused or recycled also grows. Given current population trends and the amount of wastes that will be produced, recycling and reuse needs to take a front seat in our every day lives. One particular material that interests me is plastic. Plastics are being used more and more these days throughout every facet of industry. Everywhere one may look, plastics are being used. Plastics are used in packaging, building materials, consumer goods, electronics, transportation and adhesives, just to name a few. Given the amount of goods we produce and consume each year and the fact that a good percentage of these products are made from plastics, only intensifies the need for better reuse and plastic recycling practices. Within this research paper I’m going to try and answer some popular questions about the recycling industry in regards to plastics. I’ll also shed some light on the uses of plastics, the chemical materials in plastics and some of the disposal methods used for plastics. In addition to these topics I’d also like to talk about some of the ongoing controversies and differences over recycling plastics. Finally, I’ll also provide some statistics on the plastic industry in relation to uses, recycling and disposal.
II. Recycling
So what is recycling? Why should you do it? What is recycling all about? What can be recycled? These are just some of the questions posed by the average person when it comes to disposing of goods to the waste stream. “Recycling today is, and must be understood as, a solid waste management strategy. A method of solid waste management equally useful as landfilling or incineration and environmentally more desirable. Today it is clearly the environmentally preferred method of solid waste management.” (Lund, Herbert F., page 1.1).
Only after World War II did growing populations, enhanced scientific understanding of the environment and the concept of finite resources combine to form a conscience understanding of the detrimental nature of land or ocean disposal practices. This greater understanding of pollution and wastes began to demand greater regulation of disposal practices. The inability of local governments to deal with disposal and wastes quickly led to federal involvement and assumption of responsibilities. “The first federal solid waste management law was the Solid Waste Disposal Act (SWDA) of 1965, which authorized research and provided state grants.” (Lund, Herbert F., page 1.4). Two years later the Solid Waste Disposal Act was amended by the Resource Recovery Act, and the federal government was now required to issue waste disposal guidelines. Then, in 1970 the Clean Air Act was passed which established federal authority to combat smog and air pollution leading to the shutdown of many solid waste incinerators. “Although all 50 states had some kind of solid waste regulation by the mid-1970s, it was the Resource Conservation and Recovery Act of 1976 (RCRA) that created the first truly significant role for the federal government in solid waste management.” (Lund, Herbert F., page 1.4). RCRA emphasized the conservation of resources, particularly energy conservation, and recycling as preferred solid waste management alternatives. These acts combined to encourage an explosive growth for waste-to-energy plants and to some extent the recovery of methane gas for fuel from landfills. Waste-to-energy plants are generally perceived to be a form of recycling solid waste, as its use as a fuel to create energy does return a significant part of the waste stream to a useful product. All of these considerations have led to both a legislated and public demand for recycling as the preferred solid waste management strategy today and in the future. “The willingness of government to require and subsidize recycling when necessary has grown to enormous proportions.” (Lund, Herbert F., page 1.4).
Recycling remains an elusive concept about which everyone thinks they have a clear understanding until they begin to practice it. Although most people understand the relatively simple tasks required to participate, the subtleties necessary for the interplay of both the public and private sectors needed to return those materials to industry as raw materials and the methods employed to do so require definitions other than common language. “The terms recyclable materials, recovered materials, and recycled materials all are needed to define the concept of recycling and usually require definition in various state regulations.” (Lund, Herbert F., page 1.5). The general public’s perception of what recycling is remains largely limited to those visible elements including curbside programs, recycling centers and a vague understanding that this is good for the environment because these materials do not go to a landfill or incinerator. Recycling occurs for several reasons: altruistic reasons, economic imperatives and legal considerations. The first reason, protecting the environment and conserving resources have become self evident as being in everyone’s general interest. The second reason, the avoided costs of disposal of wastes has risen to a level where when combined with the other costs associated with recycling, it now makes sense, economically, to recycle many materials. “Finally, in responding to both public demand and a growing lack of alternative waste disposal methods, government is requiring recycling and providing for a wide variety of economic and civil penalties and incentives in order to encourage recycling.” (Lund, Herbert F., page 1.5).
III. Recycling Plastics
“Every hour, Americans toss out 2.5 million plastic bottles; only a small percentage are recycled.” (Gay, Kathlyn, page 14). Today, plastics constitute one of the fastest growing categories of materials used and disposed of in our economy. Plastics comprise about 10 percent of the weight and nearly 33 percent of the volume of the municipal solid waste stream. According to the Environmental Protection Agency (EPA), about 40 billion pounds of plastics are generated as municipal solid waste in the United States. “Plastics packaging comprises 12 percent of all packaging, although it only makes up 4 percent (16 billion pounds) of all municipal solid waste by weight.” (Lund, Herbert F., page 14.2).
“Plastics are petroleum-based synthetic materials whose main constituents are carbon and hydrogen.” (Wolf, Nancy & Ellen Feldman, page 104). Most plastics that are recycled come from the thermoplastic family, which represents about 90% of all plastics sold. Thermoplastics can be readily recycled as they melt when heated to high temperatures. The entire spectrum of packaging plastics come from the thermoplastic family. “Common thermoplastics include polyolefins (polyethylene, polypropylene), styrenes (polystyrene, acrylonitrile butadiene styrene), vinyls (polyvinyl chloride, polyvinylidene chloride), and thermoplastic polyester (polyethylene terephthalate).” (Wolf, Nancy & Ellen Feldman, page 106). The other group of plastics which comprise the remaining 10% are known as thermosets. Thermosets are insoluble and infusible, and cannot be resoftened or melted by heat. Thermosets include phenolics, epoxies, urea-formaldehyde resins and crosslinked polyesters.
Recycling processes are firmly established for materials such as glass, paper and metals but the recycling of plastics is in its infancy. Recycling of plastics, like all other materials, is highly desirable based on energy use alone. Recycling of scrap plastics from the production line has been in place for many years, but recycling of post-consumer plastics has been lagging. “The recycling of plastics is different from the recycling of glass and metals. Whereas glass bottles and metal cans come back into use in the same mode, many recycled plastics must be made into other products, due to the inability of plastics to be remanufactured and sterilized to meet food-contact standards.” (Wolf, Nancy & Ellen Feldman, page 9). While some pilot programs are beginning to produce recyclable containers, most recycled plastics become fiber for carpets or jacket filler and some combined plastics are being made into furniture.
One of the main problems in the recycling of post-consumer plastics is the high cost of transportation and collection. Most empty plastic packages and containers occupy a large volume and small towns may not be able to collect enough tonnage to sustain their recyclability as part of an economically viable program. “One proposed solution calls for plastics manufacturers to assist localities in financing grinders and other equipment that reduce plastics into a denser form that is more economical to transport.” (Wolf, Nancy & Ellen Feldman, page 9). Also, the plastics industry, with help from the American Plastics Council (APC), has sponsored research aimed at driving down the cost of collecting, processing, sorting and reclaiming plastics. However, despite the costs, recycling continues to be highly valued by the American public and communities continue to offer collection services for recyclables.
“Since most of the energy required to produce a plastic product goes into the production of feedstock materials, not the manufacturing process, plastic wastes retain most of their original energy content.” (Wolf, Nancy & Ellen Feldman, page 64). So, producing a plastic product from scrap plastic instead of virgin resin saves about 85-90 percent of the energy otherwise used. “The plastics industry annually recycles approximately 4 billion pounds of post-consumer and pre-consumer scrap plastics. This does not include the recycling of several billion pounds of process scrap (regrind) that is incorporated straight back into the manufacturing process.” (Lund, Herbert F., page 14.3). Of these 4 billion pounds of plastics that is recycled, 1.4 billion pounds are pre-consumer scrap plastic and 2.6 billion pounds are post-consumer plastics.
Recycling plastics requires five necessary parts in order to be successful. These five parts are collection, processors, reclaimers, end users and customers. Collection programs are needed for business, industry and the general public. Processors locally prepare collected plastics for the market by densifying and sorting them into an economical form for long-distance shipment. Reclaimers transform the recovered product into feedstock materials. End users convert the reclaimed material into recycled products and consumers are needed to purchase the recycled-content products. The infrastructure for reclaiming, processing and collecting post-consumer plastics grew enormously from the late 1980s through the late 1990s. “Before 1998, post-consumer plastics recycling consisted primarily of soft drink bottles collected from a few states requiring deposits, and the plastic casing from returned lead-acid vehicle batteries.” (Lund, Herbert F., page 14.3). Today, there are a number of community collection programs that offer curbside pick-up or drop-off sites for select types of plastic products for 80 percent of the United States. However, recovery of post-consumer plastics through community collection programs has not kept pace with reclamation capacity and end-user demand for post-consumer plastics. As a result, these plants operate well below their capacity.
End-user markets for post-consumer recycled plastics are quite diverse. Such products that are produced are plastic bottles, carpet, strapping, pipe and plastic lumber. Some states have sought to increase plastics recycling by passing legislation that mandates that manufacturers use certain recycled content levels for some products. A topic discussed in class. While these actions have helped, they’ve also done little in the grand scheme of things to divert plastics from disposal. Most people who participate in recycling programs do so because of the environment and because they have been provided with a means of recycling plastics for curb-side pickup. Other mechanisms used to improve diversion include community recycling education and awareness, expanding recycling programs and implementing a pay as you throw (PAYT) program wherein homes pay based on the amount of waste that’s disposed of and collected.
The primary recycling of plastics, which conserves the greatest amount of energy, involves the reconversion of uncontaminated plastic waste into its original pellet or resin form. The recycled version contains chemical and physical characteristics similar to those of the original product. “Primary recycling is suitable mainly for industrial wastes, since they generally consist of one type of resin and have not been contaminated by use in consumer precuts.” (Wolf, Nancy & Ellen Feldman, page 64).
Secondary recycling converts scrap plastic or waste into products with characteristics far less demanding than the original product. This process uses plastic wastes, mostly post-consumer wastes, which are not suitable for direct reprocessing due to contamination.
Tertiary recycling converts plastic waste into a fuel for chemicals or for direct energy and quaternary recycling is the generation of energy from the burning of plastic wastes.
As mentioned earlier, the one point about recycling post-consumer waste plastics is that, unlike materials such as metals and glass, plastics cannot be sterilized at present and reused for food packaging. So, for example, recycled plastic soda bottles do not come back as other bottles but as pillows, fiber, plastic lumber, etc. “While it is desirable to recycle as much plastic as possible, most plastics cannot be used in the “closed-loop” recycling so advantageous to other post-consumer materials.” (Wolf, Nancy & Ellen Feldman, page 65). Although much progress has been made, the recycling of post-consumer plastics is limited by the absence of a strong recycling infrastructure. “The main obstacle to increased recycling include: the lack of economically feasible collection, separation, and transportation mechanisms; the dearth of large-scale commercial recycling operations capable of handling a heterogeneous mix of contaminated post-consumer materials; and the lack of steady and demanding markets for recycled plastic products.” (Wolf, Nancy & Ellen Feldman, page 66).
IV. Resource Recovery – Plastics
The waste option for plastics, alternative to landfilling is modern incineration, or resource recovery. Incineration recovers energy through combustion which is converted into steam or electric power. Resource recovery has and will become more popular as landfill space runs out. Resource recovery plants are not new and have been in operation for some years in the United States, Europe and Japan. However there are many environmental hazards associated to these plants such as gas stack emissions and landfilled bottom ash containing toxics and heavy metals leftover from the incineration process. These environmental hazards have increased tremendously due to the fact that many plastics are made up of a number of different chemicals such as plastic resins, laminates, plasticizers and additives. Although plastic waste has a high energy content and burns efficiently, leaving little residue, there remains many unanswered questions concerning the effects of burning and what these effects have on human health and the environment. Most incinerators are mass burn incinerators where 85 percent of the volume of wastes is destroyed. However, emissions from these mass burn incinerators may include acid gases, oxides of nitrogen, particulates, heavy metals and trace organic compounds.
V. Uses of Plastics
As stated earlier, plastics constitute one of the fastest growing categories of materials used and disposed of in our economy today. Plastics are used for so many different materials and used in so many different industries. The two major industries where plastics are used are the packaging industry and the construction and building industry. Plastics are also used in transportation, consumer goods, furniture, electrical components and adhesives. For this paper I will primarily focus on the packaging industry and how that relates to recycling. Since plastics are so prevalent in the packaging/consumer industry they will have an affect on recycling rates. The increase in plastics may pose serious problems for waste disposal operations, which are almost all managed by local governments. As landfill space diminishes and as new landfills are becoming nearly impossible to site, solid-waste planners must look to other methods of waste management. “Resource recovery through mass-burn incineration, the alternative most frequently mentioned, is often cited as an acceptable method of “recycling” waste plastic (due to the high energy content of the plastics), but serious concerns over health issues have been raised.” (Wolf, Nancy & Ellen Feldman, page 13).
The use of plastics in packaging has steadily increased over the years with projections climbing well above 20 billion pounds per year. Figures for construction and building materials are slightly lower since the use of plastics in this stream has a longer life span, generally, 25 to 50 years. Consumer and institutional goods make up the third largest category of plastics. This category includes all carryout packages, disposal packages used in fast food, hospitals, and prisons, throw away razors, lighters, pens, watches and cameras.
VI. Plastics – Packaging
By volume, it is estimated that packaging materials account for more than one-third of municipal solid waste in the United States. The packaging industry is the largest consumer of plastics using one-third of all resin produced annually for films, soft drink containers, material on bottles and rigid containers and for coating on many other packing materials. “Packaging is also the largest single source of plastic waste, reaching approximately 13 billion pounds a year, or 40 percent of all plastic waste.” (Wolf, Nancy & Ellen Feldman, page 16). The two largest categories of current use are packaging film and rigid containers, accounting for 35 percent and 51 percent of plastics, respectively. The other two categories behind these are coatings listed at 9 percent and closures listed at 5 percent.
Plastic packaging materials are composed of a variety of different resins and resin combination of which the most common are low-density polyethylene (LDPE), high-density polyethylene (HDPE), polystyrene (PS), polyvinyl chloride (PVC) polypropylene (PP) and polyethylene terephthalate (PET). Polyethylene, low and high density, make up over 60 percent of the plastic packaging waste stream. Low density polyethylene film is used in applications such as grocery sacks and bread wraps, while high density polyethylene is used in over 50 percent of plastic containers such as milk, water, laundry detergent and bleach.
Polyethylene terephthalate (PET), primarily used in soft-drink bottles, constitutes approximately 14 percent of plastic containers and is now the most widely used soft-drink container, based on the total volume of soft drinks sold in the United States. The amount of resins used in these soft-drink bottles doubled by 1995 with estimates close to 2 billion pounds being used. This figure is expected to steadily rise as plastics are used more and more in the packaging industry.
Other materials used in packaging, to a lesser extent, include ethylene vinyl alcohol (EVOH) as an oxygen barrier, polyvinyl acetate as an adhesive and ethylene vinyl acetate (EVA) copolymer. “The use of these materials reflects an important recent development in plastic packaging – the use of composite, or multilayer, packaging. These packages contain layers – sometimes as many as 12 – of different types of resins and other materials.” (Wolf, Nancy & Ellen Feldman, page 18). For example, a squeezable ketchup bottle consists of a layer of polypropylene (PP), an adhesive layer, an oxygen barrier layer (EVOH), another adhesive layer and another layer of PP. The use of the EVOH allows manufacturers to package in plastic many foods that they previously couldn’t, because of possible contamination. Many composite packages are now replacing materials with high recycling histories, such as paperboard and glass. The reasons for these changes include increased customer convenience, longer shelf life and lighter weight. However, the disposability of the packages and the environmental impacts of disposal have been largely overlooked. “As complex combinations of plastic become more common in packaging, the potential recyclability of solid-waste stream will decrease, since there is no recycling mechanism for these combination packages.” (Wolf, Nancy & Ellen Feldman, page 20).
“Five recycled soft drink bottles will make enough fiberfill for a man’s ski jacket. 1,050 recycled milk jugs can be made into a six-foot park bench. The United States makes enough plastic film each year to shrink-wrap the state of Texas. If only 10% of Americans bought products with less plastic packaging only 10% of the time, approximately 144 million pounds of plastic could be eliminated from our landfills.” (Martin, Sam, Garbage and Recycling, page 69).
VII. Plastics – Building & Construction
The second main category where plastics are used is in the building and construction industry. This industry consumes over 15 billion pounds of plastics in the form of pipes and fittings, plumbing, bathroom fixtures, interior/exterior building materials and air supported structures. “Unlike packaging, these uses of plastics do not immediately impact the waste stream, but their eventual disposability must be considered in waste management planning for the intermediate and long term.” (Wolf, Nancy & Ellen Feldman, page 21). Post-consumer plastic wastes from the building and construction sector is projected to be well over 3.9 billion pounds or 8.9 percent of all post-consumer plastic waste these days and figures are projected to continually rise. The one good note about plastic building and construction materials is that their life span last 25 to 50 years.
VIII. Opposing Viewpoints
Why consider opposing viewpoints?

The only way in which a human being can make some approach to knowing the whole of a subject is by hearing what can be said about it by persons of every variety of opinion and studying all modes in which it can be looked at by every character of mind. No wise man ever acquired his wisdom in any mode but this.”

John Stuart Mill
There are so many opposing viewpoints when it comes to garbage, landfills, incineration, recycling, and the list goes on. I think it’s important to understand and listen to opposing viewpoints when it comes to this topic. As we have learned in glass, wastes isn’t going away and it’s something we’ll have to deal with as a nation and world as population increases, technology grows and ultimately as suitable land space diminishes. I just wanted to list here in this section some opposing view points on particular topics related to landfills, recycling and out waste problem.
Many feel that landfills are dangerous and pose serious threats to human health and the environment. One viewpoint states that the rates of cancer can be directly associated with chemicals found in landfills and proximity to landfills. A study examined the occurrence of seven kinds of cancer among men and women living near landfills where naturally occurring landfill gas is thought to be escaping into the surround air. “Of the 14 kinds of cancer studied (7 each in mean and women), 10 (or 71%) were found to be elevated but only two (bladder and leukemia in women) achieved statistical significance at the 5% level.” (Montague, Peter Garbage and Recycling, page 36).
The opposing viewpoint asserts that modern landfills are much safer than dumps of the past. Advanced technologies such as liners and collection systems for garbage produced methane gas make modern landfills safe. “When operating properly, it stinks, if at all, only where incoming trucks are dumping the day’s input. Its input is carefully tracked from birth at some garbage collector’s place of business to its eventual graveyard, the landfill. It is buried daily in a complicated protective layer cake with intricacies that boggle the mind. And its leachate is collected through a maze of pipes and valves that resemble a miniature oil refinery.” (Angst, Bud, Garbage and Recycling, page 43).
Opposing viewpoints such as these really open the eyes when it comes to learning and understanding just exactly what’s happening with our wastes.
When it comes to recycling there are opposing viewpoints. Many feel that recycling is a must while others feel that it’s detrimental to the environment and too costly to see the benefits. “Compared to landfilling, recycling is the economic and environmental favorite by a long shot.” (Martin, Sam, Garbage and Recycling, page 62). However, others feel differently. “Recycling is merely an aspirin, alleviating a rather large collective hangover.” (Lilienfold, Robert and William Rathje, Garbage and Recycling, page 70).
IX. Conclusion
To me, it’s apparent that recycling is very important and a subject that all families, communities, business’s, etc. should embrace. Particularly with the plastics industry and the amount of plastics this country uses and produces each year. It’s amazing just how much our society has changed with the introduction of plastics for industries such as manufacturing, building and construction, transportation and most importantly, consumer goods. We’ve changed as a nation to being a disposal society, a society that looks for something simple and easy. With products hitting the shelves in record numbers packaged or containing plastics, it’s essential for us to recycle and continue to develop technologies to combat the excessive wastes we generate. I think pollution prevention is the key to at least help alleviate the strains of wastes when it comes to materials that need to be or must be recycled and handled carefully.

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