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PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.7 However, straightforward comparisons between amounts of plastic recycled from “munic- ipal solid waste” cannot be made, either, since definitions differ. Some, but not all, of the material identified in Europe as belonging to the distribution and industry, agriculture, and electrical and electronics sectors, for example, would be classified as part of municipal solid waste in the United States. Countries within western Europe differ considerably in recycling rates for plastics. APME reports that, in 2003, Germany had the highest rate at 27.1 percent, while the rate in Greece was only 2.2 percent (Fig. 8.10). Recycling rates for packaging plastics are gen- FIGURE 8.7 Amounts recycled and recycling rates for plastics in U.S. municipal solid waste. 2 FIGURE 8.8 Amounts recycled and recycling rates for plastics in western Europe. 6 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.8 CHAPTER 8 TABLE 8.1 Recovery of Selected Materials in U.S. Municipal Solid Waste. (Recovery includes both recycling and composting.) 1 Material Amount recovered (million tons) Recovery rate (%) 2000 2003 2000 2003 Paper and paperboard 37.5 40.0 42.8 48.1 Glass 2.66 2.35 21.1 18.8 Steel and other ferrous metals 4.61 5.09 34.2 36.4 Aluminum 0.86 0.69 27.4 21.4 Other nonferrous metals 1.03 1.06 67.9 66.7 Plastics 1.35 1.39 5.5 5.2 Rubber and leather 0.82 1.10 12.6 16.1 Textiles 1.29 1.52 13.7 14.4 Wood 1.24 1.28 9.6 9.4 Food wastes 0.68 0.75 2.6 2.7 Yard trimmings 15.8 16.1 56.9 56.3 FIGURE 8.9 Plastics recycling in western Europe by category, 2003. 6 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.9 erally higher than the rates for plastics as a whole, exceeding 20 percent for mechanical re- cycling alone in Austria, Germany, Norway, Belgium, Italy, Netherlands, and Spain. France, the UK, and Switzerland have mechanical recycling rates between 15 and 20 per- cent; Denmark, Finland, Portugal, and Sweden have rates between 10 and 15 percent. Ire- land has a rate between 5 and 10 percent, and Greece between 0 and 5 percent. 10 In Australia, a total of 189,385 tonnes of plastics were recovered for recycling in 2003, for a recycling rate of 12.4 percent. Of this, 69 percent was processed domestically, and the remainder was exported, mostly to Asia. Plastics recycling has increased significantly in the last decade, although it did decline in 2001 and 2002. There was a major rebound in 2003, with the total amount of plastics recycled more than twice that of 1997 and 20 per- cent higher than in 2002 (Fig. 8.11). This material was nearly evenly divided between mu- nicipal waste (49.3 percent) and commercial and industrial waste (49.6 percent); the remaining 1.1 percent was building, construction, and demolition waste. Plastic packaging totaled 71.2 percent of the total wastes recovered, so, obviously, a significant fraction of the commercial and industrial waste would have been defined as municipal waste in the United States. The overall plastic packaging recycling rate was 20.5 percent. 11 Polyethylene terephthalate (PET) had the highest recycling rate of all plastics in U.S. MSW in 2003, 14.3 percent, followed by high-density polyethylene (HDPE) at 9.1 per- cent, as can be seen in Fig. 8.12. High-density polyethylene is recovered in the greatest to- tal amount, followed by PET. The most prevalent plastic present in the MSW stream is low and linear low-density polyethylene (LDPE/LLDPE), followed by HDPE. 1 Table 8.2 shows the amounts of the major plastic resins in U.S. MSW in 2000 and 2003, and the amounts recovered for recycling. It is readily apparent that overall plastics recycling rates have fallen during this time period. Only the HDPE rate has increased. In Australia, PET also had the highest recovery rate in 2003, 31.5 percent, followed by HDPE at 23.1 percent (Fig 8.13). The total amount of HDPE recovered was also highest, with PET in second place. 11 Calculation of recycling rates is controversial. There have been charges in the past that surveys that ask recyclers for data produce inflated figures and thus inflate recycling rates. Surveying organizations take steps to minimize this problem but cannot totally eliminate it. The reverse problem is the omission of organizations that do recycling, thus underesti- mating recycling rates. FIGURE 8.10 Plastics recycling in western Europe by country, 1999 and 2003. 6 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.10 CHAPTER 8 FIGURE 8.11 Plastics recycling amounts and rates in Australia. 7 FIGURE 8.12 U.S. plastics recycling rates by resin, 2003. 1 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.11 A more fundamental problem than data accuracy is the matter of definition—what should count as recycled? The two most common options are (1) determining the amount of material collected for recycling and (2) determining the amount of material delivered for reuse. Since, typically, 5 to 15 percent of collected material is lost during processing (mostly because it is some type of contaminant such as a paper label, product residue, un- wanted variety of plastic, or other material), recycling rates calculated using these two methods can differ substantially. TABLE 8.2 Recovery of plastics in U.S. MSW by resin. 2 Resin 2000 2003 Amount recycled (thousand tons) Recycling rate (percent) Amount recycled (thousand tons) Recycling rate (percent) PET 430 17.3 410 14.3 HDPE 420 8.7 470 9.1 PVC negligible 0 negligible 0 LDPE/LLDPE 150 2.6 150 2.4 PP 10 0.3 10 0.3 PS negligible 0 negligible 0 Other 330 7.1 350 6.9 Total plastics 1340 5.4 1390 5.2 FIGURE 8.13 Australian plastics recycling rates by resin, 2003. 7 Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.12 CHAPTER 8 In the United States., the American Plastics Council (APC) is a major source of infor- mation about plastics recycling rates. In 1997, APC switched, in determining recycling rates, from using the amount of cleaned material ready for use to using the amount of ma- terial collected for processing. They justified this decision by claiming it is more in keep- ing with the way recycling rates are calculated for other materials—a claim that is true for some materials, such as paper, but not true for others, such as aluminum. This change brought considerable criticism, exacerbated by the fact that it occurred at a time when re- cycling rates, calculated in the same fashion, were declining. APC was accused of trying to mask the extent of the decline by the change in methodology. For example, the PET bot- tle recycling rate in 1997 was 27.1 percent based on material collected but only 22.7 per- cent based on clean material ready for reuse. 12 APC drew additional criticism by deleting polystyrene food service items from the definition of plastic packaging, beginning in 1995, which also had the effect of increasing the reported recycling rate for packaging plastics. The Environmental Defense Fund (EDF) even issued a report, titled “Something to Hide: The Sorry State of Plastics Recycling,” in which they highlighted the difference the change in method of calculation made in the reported recycling numbers. 13 Now, how- ever, this change in methodology has been generally accepted. A related issue is how to deal with imports and exports of recyclable materials. Gener- ally, imported goods that enter the waste stream are added to those produced domestically, and exported goods are subtracted, in calculating the denominator of the recycling rate— materials available for recycling. Most countries count collected recyclables that are ex- ported for recycling as part of the recycled stream, since they do represent materials di- verted from disposal. The issue of how to count collected recyclables being imported for recycling is more controversial. This has not been an issue for the plastics industry, but the U.S. aluminum industry has been criticized for including imported scrap cans in calculat- ing the recycling rate for U.S. beverage cans. 14 8.1.4 Environmental Benefits of Recycling and Use of Biodegradable Plastics An obvious benefit of recycling and use of biodegradable plastics is that both reduce the requirement for landfill or incineration of waste materials. Items that are recycled are, by definition, diverted from the waste stream. Biodegradable plastics can be managed by composting, generally perceived as more environmentally beneficial than landfill or incin- eration. In fact, advocates of composting often refer to it as natural or biological recy- cling. Often, although not always, another benefit of recycling is cost reduction. For example, use of regrind became routine because of the monetary savings it provided. Similarly, cer- tain plastics industries for years have relied on a combination of off-spec and recycled plastics because of their lower price. The desire to benefit from consumer preferences for recycled material coupled, in some cases, with legislative pressures have led, on occasion, to the anomalous situation of recycled plastic being worth more per pound than virgin resin, but these situations are usually short lived. Recent increases in the cost of oil and natural gas, with consequent increases in prices for virgin resins, provide more opportu- nity for recycled plastics to be economically competitive. Biodegradable plastics are still generally more expensive than the synthetic plastics they compete with, although the price differential is decreasing. If these biodegradable plastics are also biobased, increases in price of oil and natural gas may make them more competitive. Additional benefits from recycling of plastics result from the fact that use of recycled resin displaces use of virgin materials and thus reduces depletion of natural resources. Re- Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.13 cycling processes generally produce fewer environmental effluents than do processes that produce virgin resin, so the use of recycled plastics usually results in a decrease in air and water pollution. Biobased plastics use renewable materials as a feedstock, so they also can reduce resource depletion. A factor that is certain to become increasingly important in the next decade is that the use of recycled plastics often results in significant energy savings, compared to the use of virgin resin. For example, Fenton 15 calculated the total energy requirement for a low-den- sity polyethylene grocery bag to be 1400 kJ, while a bag with 50 percent recycled content required only 1164 kJ, for a savings of nearly 17 percent. A DOE report concluded that re- cycling PET products such as soft drink and ketchup bottles requires only about a third of the energy needed to produce the PET from virgin materials. 16 Again, recent increases in energy prices make this advantage even more significant. In the near future, efforts to reduce emissions of greenhouse gases may become an im- portant driver for use of plastics in general and for biobased and recycled plastics in partic- ular. For example, a recent study by the Center for Packaging Technology (Cetea) in Spain reported that PET recycling reduces carbon dioxide emissions by 25 percent and methane emissions by 18 percent. 17 In the farther-term future, when oil supplies diminish signifi- cantly, production of plastics from renewable feedstocks will likely be critical. 8.2 RECYCLING COLLECTION For plastics recycling to occur (or for recycling of other materials), three basic elements must be in place. First, there must be a system to collect the targeted materials, to gather them together. Second, there must be a facility capable of processing the materials into a form that permits them to be used to make a new product. Third, new products made in whole or part from the recycled materials must be manufactured and sold. A breakdown in any part of this system eventually stops the whole process. Because of this, efforts to in- crease recycling rates must pay attention to markets for the recycled materials as well as to the infrastructure to allow collection and processing of the materials. Collection of plastics for recycling often occurs as part of a system designed to collect a variety of materials, not just plastics. Similarly, initial processing, in which collected ma- terials are separated by generic type, often occurs in a multimaterial recycling facility. 8.2.1 Collection of Materials For postconsumer materials, including plastics, the most difficult part of the recycling pro- cess may be getting the material collected in the first place. Industrial scrap is “owned” by the industrial entity that produced it. If the owners cannot get the scrap recycled, they will either have to dispose of it or pay some other business to do so. For much consumer scrap, there is little or no monetary incentive for its owner, the individual consumer, to direct it into a recycling system. Furthermore, industrial scrap tends to be concentrated, with sub- stantial amounts of material in relatively few locations, making it relatively easy to collect. Postconsumer materials are typically very diffuse, so a more elaborate collection infra- structure is needed to get this material gathered together in quantities that make its pro- cessing economically viable. There are three main approaches to collection: (1) go out and get the material, (2) cre- ate conditions such that the material will be brought to you, or (3) use a combined ap- proach. There is a trade-off between motivation and convenience in getting people to participate in recycling by appropriately diverting the targeted recyclables from the waste Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.14 CHAPTER 8 stream into the recycle stream. Highly motivated individuals will participate in recycling even if they have to go to considerable effort to do so. If systems are set up to be very con- venient, less motivation will be required to get people to participate. Therefore, increasing participation in recycling can be increased by providing greater motivation, by providing greater convenience, or by a combination of the two. Usually (although not always), sys- tems that go out and get the materials provide greater convenience than those that require individuals to deliver the materials to a collection point. When evaluating the success of recycling collection programs, authorities may report either participation rates or diversion rates. Participation rates reflect the proportion of people (often calculated by household rather than by individual) who actively participate in recycling. For curbside programs, a household is usually counted as participating if they put out (or deliver) any recyclables for collection any time in a one-month period. Diver- sion rates instead calculate the proportion of the targeted material(s) that is directed into the recycling stream rather than the waste stream. In principle, diversion rates are easier to calculate and more informative than participation rates, as they more directly get at the is- sue of how well a program is doing in acquiring materials for recycling. In practice, the only way to absolutely measure diversion is to do waste sorts to see what recyclables are left in the garbage stream. Due to the complexity and expense, not to mention the mess, of doing so, diversion rates are usually calculated rather than measured, based on amounts of targeted materials that are expected to be in the waste stream and measurements of the amounts that reach the recycling stream. This is the method used to obtain the recovery and recycling values in the series of EPA solid waste reports, for example. 8.2.1.1 Beverage Bottle Deposit Systems. Recycling of postconsumer plastics in the United States got its start with the recycling of PET beverage bottles in states with bottle deposit legislation. The 5 or 10 cents per container deposit proved to be a sufficient incen- tive to get consumers to bring in 90 percent or more of the covered containers to central- ized collection points (usually retail stores). This, in turn, spurred the development of effective reprocessing systems for these bottles and end markets for the recovered resin. In recent years, redemption rates (and therefore recycling rates) for containers covered by de- posits have fallen. One reason may be that 5 cents is not as strong a motivation now as it was decades ago, when most of these laws were passed. Inflation has greatly decreased the real value of the deposit. A recent study reported that a 1981 nickel was worth only 2.5 cents in 2001. 18 One support for this view is that redemption rates in Michigan, the only state with a 10-cent deposit, have not fallen as much as those in most other states—re- maining well above 90 percent. Beverage bottle deposit programs are still relatively rare in the United States. Only 11 states have passed this type of deposit legislation (Table 8.3). 19 Initially, these laws were passed as litter-reduction measures. Therefore, they targeted beer and soft drink contain- ers, since these represented a large and highly visible portion of litter. Later, several states recognized the value of these laws in achieving recycling, and both Maine and California amended their deposit laws to cover a wider variety of beverage containers in explicit ef- forts to increase beverage container recycling. The most recent deposit state, Hawaii, had recycling as an explicit goal when the law was initially passed. The consumer pays a deposit, usually 5 cents, when buying the container and then re- ceives a refund of that fee when the bottle is returned to a designated collection point. In most cases, any retailer that sells beverages of that type is obligated to accept the returns and refund the deposit. The majority of states provide for a handling fee for the retailer to at least partially offset the costs of managing the system. Several years ago, Maine extended its early deposit law in an explicit attempt to in- crease recycling. The state now has deposits in place on most beverages, with the excep- tion of milk. Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.15 TABLE 8.3 Bottle Deposit Legislation in the United States 19 State Containers covered Characteristics California Beverages except milk, infant formula, distilled spirits, wine, medical foods, 100% fruit juice in 46 oz or larger containers, vegetable juice in containers lar ger than 16 oz, large refillable beverage containers; some other specified containers such as multimaterial pouches exempted Refund value: 4 cents if capacity less than 24 oz, 8 cents if capacity 24 oz or greater; industry may be required to pay processing fee to cover part of recycling cost Connecticut Beer, malt beverages, carbonated soft drinks, soda water , mineral water 5¢ deposit Delaware Nonalcoholic carbonated beverages, beer, and other malt be verages 5¢ deposit, aluminum cans exempt Hawaii All nonalcoholic drinks except milk and dairy; beer , malt beverages, mixed spirits, mixed wine; aluminum, glass, PET, and HDPE containers only 5¢ deposit plus 1¢ nonrefundable container fee; containers over 64 oz exempt Iowa Beer, soda, wine, liquor 5¢ deposit Maine All beverages except dairy products and unprocessed cider 5¢ deposit, 15¢ on wine and liquor Massachusetts Carbonated soft drinks, mineral water, beer, and other malt beverages 5¢ deposit; containers 2 gal or larger exempt Michigan Beer, soda, canned cocktails, carbonated water, mineral water, wine coolers 10¢ deposit New York Beer, malt beverages, soda, wine coolers, carbonated mineral w ater 5¢ deposit Oregon Beer, malt beverages, soft drinks, carbonated and mineral water 5¢ deposit Vermont Beer and soft drinks, malt beverages, mixed wine drinks, liquor 5¢ deposit, 15¢ on liquor bottles, all glass bottles must be refillable Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.16 CHAPTER 8 California’s system is actually a refund value system rather than a true deposit. Until the law was changed effective January 2000, this cost was buried in the product price rather than charged as a separate item. Containers can be returned only to designated re- demption centers unless there is not one within a specified distance, so return of contain- ers is often significantly less convenient than it is in most deposit states, where containers can be returned to any retailer selling the covered beverage. It should also be noted that, in California, manufacturers must pay a processing fee to the state, in addition to the re- fund value, to cover the costs of recycling beverage containers covered by the refund value system. California extended its refund value system, effective January 2000, to a wide variety of beverages, again in an explicit attempt to increase recycling of plastic bottles. Water and fruit juice containers are included, along with several other beverages (see Table 8.3). Ini- tially, this produced a reduction in redemption rates. For the first half of 2000, the redemp- tion rate fell to 70 percent from 80 percent in the first half of 1999. The decline was especially steep for PET, which dropped from 83 percent to 40 percent. The overall Cali- fornia redemption rate in 1999 for containers covered by the refund value system was 76 percent. The rate in the second half of the year was lower than in the first half, as has been the case for the last several years. The refund value started out at 1 cent. At the time of the expansion to cover additional containers, it was 2.5 cents per container for sizes less than 24 oz and 5 cents per container 24 oz or larger. Effective January, 2004, the refund value increased to 4 cents per container under 24 oz and 8 cents per container 24 oz or larger. 20 The result was an increase in recycling amounts and rates. The number of con- tainers recycled reached 12 billion, up from 10.5 billion in 2003 and 10.6 billion in 2002. The beverage container recycling rate rose to 59 percent, compared to 55 percent in 2003, for the first increase in recycling rate since 1995. 21 The increase was attributed to efforts to increase public awareness, better customer service at recycling centers, a greater number of such recycling opportunities, and increased recycling at private businesses, in addition to the increased redemption value. 22 Recycling rates by material type continued to differ sharply, as shown in Fig. 8.14. It is important to note that beverage manufacturers must pay a processing fee to the Division of Recycling to cover a portion of the costs of pro- cessing the returned containers. For plastic containers, processing fees are lowest for PET (currently 12 percent of processing payments), somewhat higher for HDPE (20 percent), and significantly higher for other plastics (65 percent of processing payments). 23 Hawaii’s system is the newest, going into effect Jan. 1, 2005. It covers nonalcoholic drinks, except for milk and dairy products, and certain alcoholic drinks (beer, malt bever- ages, mixed spirits, and mixed wine) that are sold in aluminum, PET, or HDPE containers of 64 oz capacity or less. In addition to the 5-cent deposit, consumers pay a non-refund- able 1-cent container fee. As in California, containers must be returned to redemption cen- ters. 24 Canada has deposit systems for most beverage containers except milk in 6 of its 10 provinces. Eight of the 10 provinces have deposits on soft drink and beer containers. Re- fillable (glass) beer bottles, which account for 75 percent of all beer containers sold in Canada, are subject to a mandatory or voluntary 10-cent deposit in all provinces. New Brunswick, Nova Scotia, and Newfoundland have half-back deposit systems for nonrefill- able containers, and Prince Edward Island for alcohol containers, in which consumers get back only half of their original deposit when they return the empty container. This is in- tended to influence consumers to purchase refillable rather than nonrefillable bottles. Table 8.4 shows the deposit systems currently in place in Canada. 25 PET bottle recovery steadily increased through 2003, reaching a total of 110.0 million pounds, for a recovery rate of about 60 percent. 26 Recovery rates in western Canada, where deposits are high and the programs have a longer history, were 80 to 90 percent for large bottles and about Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2006 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS [...]... Terms of Use as given at the website PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.27 Germany does a substantial amount of feedstock recycling of plastics packaging, with a total of 330 thousand tonnes in 2002.10 In the United States, feedstock recycling is mostly limited to nylon 6, polyurethane, and PET 8.3.1 Separation and Contamination Issues When plastics. .. Terms of Use as given at the website PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.31 where it serves the same purpose as on containers, to encourage and facilitate the development of plastics recycling.59 In the EU, the same basic system is used, with some modification of the letter symbols permitted PET can be used instead of PETE, PE-HD instead of HDPE,... subject to the Terms of Use as given at the website PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.19 A negative aspect of deposit systems is that the per-container cost of managing these systems, as they are currently designed, is higher than the cost of alternative collection systems.34 A national system rather than the current multiplicity of state systems... often contain more than one type of plastic resin, resins with different colors, additive packages, and so on This contamination is one of the major stumbling blocks to increasing the recycling of plastic materials Usefulness of the recovered plastic is greatly enhanced if it can be cleaned and purified Therefore, technologies for cleaning and separating the materials are an important part of most plastics. .. type Most of these systems work well with whole containers but are not effective in separating chipped plastics or multilayer materials 8.3.5 Resin Identification Codes The first control point for separation of plastics by resin can be at the time of collection To facilitate identification of plastics packaging by resin type, and to satisfy pressure by states for such a system, the Society of the Plastics. .. subject to the Terms of Use as given at the website PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.26 CHAPTER 8 per year Another analysis found plastic bottles comprising 0.09 percent of bales of old corrugated containers and up to 0.96 percent of old newspapers, for a total of about 300 tons per year of lost containers for a 200 ton-per-day MRF operating 5 days per week A series of recommendations... of the letter symbols permitted PET can be used instead of PETE, PE-HD instead of HDPE, PVC instead of V, PE-LD instead of LDPE, and O in place of Other.60 ISO 11469:2000, Plastics Generic identification and marking of plastics products,” provides more specific identification of plastics in a variety of products, to facilitate their identification and decision making about their handling, waste recovery,... are using the ISO codes on a variety of other types of products as well For example, Hewlett Packard requires use of the ISO codes on all parts weighing 25 g or more if adequate space is available and the functionality of the part is not impaired Inclusion of the codes on smaller parts is strongly encouraged The preferred method is to mold the marking into the part, on an interior surface.63 ASTM International... recycling.74 8.3.7 Microsorting Systems Microsorting of plastics is commonly practiced for separation of lighter-than-water from heavier-than-water plastics While such separation can be done in a simple float-sink tank, hydrocyclones are often used because of their advantages in size and throughput Application of density-based separation for mixtures of plastics that are all heavier or all lighter than... in behavior of recycled plastics pose unacceptable risks For example, it is probably safe to conclude that recycled plastics will not be used for implantable medical devices It is highly unlikely that recycled plastics will be used for the packaging of sensitive drugs Other examples, of course, could also be cited where the small but real risk of unacceptable performance, or of release of some damaging . collection and processing of the materials. Collection of plastics for recycling often occurs as part of a system designed to collect a variety of materials, not just plastics. Similarly, initial. Benefits of Recycling and Use of Biodegradable Plastics An obvious benefit of recycling and use of biodegradable plastics is that both reduce the requirement for landfill or incineration of waste. subject to the Terms of Use as given at the website. PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS PLASTICS RECYCLING AND BIODEGRADABLE PLASTICS 8.9 erally higher than the rates for plastics as a whole,

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