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RECYCLINGRECYCLING
Allison M. Selk
10/13/04
CBE 562
OutlineOutline
General recycling informationDetails regarding:
– Aluminum– Plastics– Glass– Paper– Newspaper– Corrugated
General Recycling InfoGeneral Recycling Info
In 2001, US residents produced more than 229 million tons of municipal solid waste (MSW)– Approximately 4.4 pounds per person per day– Up from 2.7 pounds per person per day in 1960– Canada produces 3.75 pounds per person per day– Germany and Sweden produce 2 pounds per person per
day Recycling diverted 68 million tons from landfills
and incinerators– Almost 30% of the waste produced
Waste Generation in USWaste Generation in US
Recycling Rates in USRecycling Rates in US
Recycling Rates in US of Recycling Rates in US of Specific MaterialsSpecific Materials
2001 Data
Recycling Rates in WI of Recycling Rates in WI of Specific MaterialsSpecific Materials
0%
10%
20%
30%
40%
50%
60%
70%
80%
YardWaste
CorrugatedCardboard
New spaper GlassContainers
Aluminumand Steel
Cans
PlasticContainers
Magazines OfficePaper
2003 Recycling Rates in WI
General Recycling ProcessGeneral Recycling Process
Collection and Processing– Curbside, drop-off centers, buy-back centers,
deposit/refund programs– Materials are then sorted and sold to manufacturing
vendors Manufacturing
– Materials are incorporated into new products, either reformed into their original use or used in new ways
Purchasing recycled products– Businesses and consumers buy products made form
recycled materials– “Closing the loop”
Key Benefits of RecyclingKey Benefits of RecyclingReduces need for landfilling and
incinerationSaves energy and prevents pollution caused
by the extraction and processing of virgin materials and the manufacture of products from virgin materials– In 2000, recycling resulted in an annual energy
savings of 660 trillion BTUs (equivalent to the energy used in 6 million homes annually)
Key Benefits of Recycling (cont.)Key Benefits of Recycling (cont.)
Decreases emissions of Greenhouse Gases (GHG)– In 1996, recycling in the US prevented the release
of 33 million tons of carbon into the air
Conserves natural resources while providing raw materials to industry
Creates jobs
AluminumAluminum
3.2 million tons of aluminum in MSW stream in 2001
40% was recovered for recyclingAverage aluminum can contains 40% post
consumer recycled aluminumMarket value in WI in 2004 ranged from
$850 to $1,200 per ton (baled)
How Aluminum Is MadeHow Aluminum Is Made Mine deposits of
bauxite ore and refine into alumina
Alumina and electricity are combined with a molten electrolyte called cryolite
DC electricity is passed from a carbon anode into the cryolite, splitting the aluminum oxide into molten aluminum and carbon dioxide
Molten aluminum collects at the bottom of the reactor and is cast into ingots
How Recycling Aluminum WorksHow Recycling Aluminum Works Used beverage containers are collected and taken
to a material recovery facility (MRF) where they are sorted from other food containers
Need a high quality scrap free of steel, bottle caps, plastic, etc.
Cans are baled and sold to a middle man Aluminum is refined and melted into ingots Ingots are melted into can sheet, lids are
manufactured separately and the complete can is sold to the beverage industry
Benefits of Aluminum RecyclingBenefits of Aluminum Recycling Al can recycling process saves 95% of the energy
needed to produce Al from bauxite ore– Producing 20 cans from recycled materials uses the
same amount of energy as making one can from raw materials
– In 2002, 54 billion cans were recycled, saving the energy equivalent of 15 million barrels of crude oil
Reduces Greenhouse Gas emissions– Recycling 1 kg of Al saves
over 20 kg of Greenhouse gases Fast turnaround time
– Takes 6 weeks to manufacture, fill, sell, recycle, and remanufacture a beverage can
PlasticsPlastics
25.4 million tons of plastics in the MSW stream in 2001 (11% of total stream)– 11 million tons as containers and packaging– 6 million tons as nondurable goods (diapers, trash bags,
cups, medical supplies, etc.)– 8 million tons as durable goods (appliances, furniture,
etc.)
Only about 5% of total plastic is recycled but specific areas are much higher
Two Main Recycled PlasticsTwo Main Recycled Plastics PET
– Comes mainly from soft drink bottles– 36% was recycled in 2001– Market value in WI in 2004 ranged from $180
to $360 per ton (baled) HDPE
– Comes mainly from milk jugs and water bottles
– 28% was recycled in 2001– Market value in WI in 2004 ranged from $300
to $450 per ton (baled)
How Plastics Are ProducedHow Plastics Are Produced Petroleum is heated under controlled conditions
and broken down to create monomers Monomers are linked together to form the plastic
polymers Two main types
– Thermosets – solidify irreversible, useful for durability and strength
– Thermoplastics – weak bonds which allow for softening when heated, can be shaped/molded
Plastic Recycling ProcessPlastic Recycling Process
Containers are collected and sorted by plastic type, baled, and sent to a reclaimer
Reclaimer removes trash and grinds the plastic into small flakes
Flotation tanks further separate contaminates based on density
Flakes are dried, melted, filtered, and formed into pellets
Plastic Recycling Benefits and Plastic Recycling Benefits and MarketsMarkets
Recycling 1 ton of plastics saves 84% of energy needed to produce 1 ton of plastic from raw materials
Market demand for recovered plastic resin exceeds the amount of post-consumer plastic recovered from waste stream
PET – fiber for carpet and textiles, fleece jackets HDPE – bottles, trash bags, plastic lumber
GlassGlass
10.9 million tons of glass in MSW stream in 2001
22% was recovered for recycling90% of recycled glass is used to
make new containers– Also used in kitchen tiles, counter
tops, and wall insulation
How Glass Is MadeHow Glass Is Made
Sand, soda ash, limestone, and cullet (recycled crushed glass) are mixed and heated to 2600-2800 °F
Impurities (Fe, other) added for colorsMolded into the desired shape
Glass Recycling ProcessGlass Recycling Process
At MRF, workers remove large contaminants by hand and sort glass by color
Glass in crushed and is conveyed through a series of refinements
Magnets pull out metal and air currents remove lightweight material such as paper
Lasers or photodetectors can also be used to sort colors of crushed glass
Benefits Of Using CulletBenefits Of Using Cullet
Costs less than raw materialsProlongs furnace life because it melts at a
lower temperatureUses less energy
– Glass from recycled material saves 74% of the energy required to manufacture glass from raw materials
Markets For Recycled GlassMarkets For Recycled Glass
High quality cullet– Single colored– Free of contaminants– Used for making new containers
Lower quality cullet– Mixed color glass– Used for fiberglass insulation, roadbed
aggregate, driving safety reflective beads
PaperPaper
82 million tons on MSW stream in 2001 (36% of total stream, largest segment)
More than 40% of US landfill space is paper products– Paper doesn’t easily biodegrade– Newspapers from 1960s can be intact and readable
45% of total paper waste was recovered for recycling in 2001
Paper Recycling Rates By Paper Recycling Rates By SegmentSegment
Paper Recycling ProcessPaper Recycling Process
Mills mix shredded paper with waterMixture is cooked and cleaned
to create pulpA certain percentage of this pulp is mixed
with pulp created from virgin wood
Three Challenges For Three Challenges For Recycling PaperRecycling Paper
Contamination– inks, adhesives, food, broken glass, etc.
Sorting– Newsprint, office paper, etc.
Fiber degradation– Size and strength of paper fibers decrease during
manufacturing process– Degrade further with each round of recycling– Paper can usually be recycled up to 8 times
Uses of Recycled PaperUses of Recycled Paper
In 1999, 37% of raw materials used in US paper mills was recovered paper
Mixed paper collected goes into making paper towels, napkins, and bathroom tissue
NewspaperNewspaper
Market value in WI in 2004 ranged from $70 to $100 per ton (baled)
Recycled newsprint is used in new newspapers and in cellulose insulation
Market Value of NewspaperMarket Value of Newspaper
CorrugatedCorrugatedMarket value in WI in 2004 ranged from
$50 to $100 per ton (baled)Used to make new corrugated containers
and cereal boxes
ReferencesReferences1. http://www.epa.gov/epaoswer/non-hw/muncpl/i
ndex.htm
2. http://dnr.wi.gov/org/aw/wm/markets/recmarprices/index.html
3. http://www.city.fitchburg.wi.us/309753.html4. http://www.environmentaldefense.org/document
s/611_ACF17F.htm
5. http://www.wastewise.wa.gov.au/pages/recycling.asp
6. http://www.earth911.org