chapter 18 the disposable decades - 50s-90s 1. disposable life style - use once and throw away 2....
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Chapter 18The Disposable Decades - 50s-90s• 1. Disposable Life Style - Use once and throw away• 2. Convenience became necessity • 3. Results – some areas are running out of landfill space
B. Scope of the Municipal Solid Waste Problem• 1. We produce 220 million tons MSW/year– 5.8 lbs/day
– Texas? That’s 7.5 lbs/day
• 2. Historically we put our MSW in dumps and/or burned it. Wetlands or flood plains sites for dumps. Problems
• 3. Composition of MSW - Figure 18.5• Paper 38%, Yard waste 16%, Rubber, textiles 12%. Metal 8%,
Glass 6%, Glass 8%, Plastic 8% Food waste 7% • High standard of living = lots of MSW
Chapter 18C. Methods of Waste Disposal• Landfilling
• A. Cheapest and most convient method - 57% of MSW in U.S. is landfilled –
• B. Sanitary landill - clay and plastic lined depression - MSW covered each day with dirt
• C. Ground water monitored, methane production monitored - cost up to $400,000 to prepare, no O&M
• D. Siting difficult – NIMBY, NIMFYE, BANANA• E. # of landfills in U.S. has decreased but capacity has
stayed the same or increased• F. Western Europe and Japan have far fewer landfills -
recyling and incineration emphasized
http://www.tnrcc.state.tx.us/
http://www.tnrcc.state.tx.us/admin/topdoc/pd/020/02-01/waste.html
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Chapter 18Incineration
• A. 16% of MSW in U.S. incinerated - Waste-to energy
• B. Mass burning - MSW fed into furnace and burned at 1,300 degrees C - generates steam and electricity
• C. Incinerators decreases MSW 90% by volume and 75% by weight. Residues are landfilled.
• D. Environmental Issues and incineration– 1. Air pollution- release metals, acid gases,
– 2. Toxicity - dioxins and furans
– 3. Disposal of ash/residues - metals lead, cadmium, mercury and arsenic - hazardous wastes.
– 4. Costs of incinerators - $45,000,000 to $350,000,000.
– 5. Incineration and source reduction paradox
Chapter 18Source Reduction• Designing, manufacturing,purchasing or using
materials in ways that reduce the amount or toxicity of trash—Reuse also prevents waste
Examples• 1. Reduce packaging• 2. Make companies accept used packaging • 3. Sell concentrates• 4. Source Reduction requires citizens to take
action
Chapter 18Recycling • A. About 28% of MSW is recycled in U.S.
– Number likely includes composting– The Big Deal—Count what is collected or what is actually
recycled?
• 1. Bottle Bill---place deposit on bottles—encourages recycling and decreases litter
• 2. 15 states have mandatory recycling laws• • 3. Profile of what is recycled
Chapter 18 Benefits of Recycling• 1. Conservation of resources• A. Sunday edition of New York Times takes 62,000 trees
• B. Import almost all aluminum—US recycles 60% of aluminum cans
• C. Use of recycled glass saves 50% of the energy
required to make new glass—33% recycled—innovative recycling—Plano, Tx
• Energy savings from avoidance of mining, etc
Chapter 18Recycling ConcernsTechnical Concerns
– A. Hard to separate all the types of plastics– 1. High Density polyethylene (HDPE) - milk carton– 2. Polystyrene (PS)-egg carton– 3. Polyethlene terephthalate (PET) - soft drink bottles
Transportation Concerns - transporting air expensive– Mass vs volume
Economic Concerns– 1. Market for recycled materials unstable – 2. Can’t just recycle. Must purchase products made from
recycled materials– 3. Must develop incentitives to encourage use of recycled
materials
Chapter 18Composting• Natural process optimized for air/moisture
used for reducing volume of organics and producing useful product– Used for yard trimmings, sludge, soiled paper,
waste wood, etc• “If it lives it dies, if it dies it rots, if it rots it will
compost”
– 3000 facilities nationwide– 47% of yard trimmings composted in US– City of Denton example
Chapter 18Real World in Real Time: New York City-March2002
• Budget deficit has put recycling on chopping block– Savings of $57 million– Recycling of glass, metal and plastic costs $240 per ton—
almost double cost of throwing it away– How balance budget that also include police, fire protection and
teachers?– Proponents quote the following statistic: the next 1000 yrs of
trash will only fill an area 35 sq miles 100 yds deep
• Economics vs environment? • Read it yourself: http://abcnews.go.com/sections/us/DailyNews/recycling020308.html
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