Transcript Solid Waste What is a solid waste • Any material that we discard, that is not liquid or gas, is solid waste –

Solid Waste
What is a solid waste
• Any material that we discard, that is not liquid
or gas, is solid waste
– Municipal Solid Waste (MSW):
• Solid waste from home or office
– Industrial Solid Waste:
• Solid waste produced from Mines, Agriculture or
Industry
What is a Hazardous Waste?
• Hazardous waste is a waste with properties that make it dangerous or
potentially harmful to human health or the environment
• Ignitability - Ignitable wastes create fires under certain conditions or are
spontaneously combustible, or have a flash point less than 60 °C (140 °F).
• Corrosivity - Corrosive wastes are acids or bases (pH less than or equal to 2
or greater than or equal to 12.5) that are capable of corroding metal
containers, such as storage tanks, drums, and barrels.
• Reactivity - Reactive wastes are unstable under "normal" conditions. They
can cause explosions, toxic fumes, gases, or vapors when mixed with water.
• Toxicity - Toxic wastes are harmful or fatal when ingested or absorbed (e.g.,
containing mercury, lead, etc.). When toxic wastes are disposed of on land,
contaminated liquid may drain (leach) from the waste and pollute ground
water. Toxicity is defined through a laboratory procedure called the Toxicity
Characteristic Leaching Procedure (TCLP).
• Major types: Organics and Heavy Metals, Radioactive wastes
U.S. Scenario
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4.6% of world population
50% of toxic wastes
1/3rd of solid wastes
Mining (76%), agricultural (13%), industrial
(9.5%) = 98.5%
• Municipal solid waste – 1.5%
Municipal Solid Waste (MSW)
Waste Management
Recycling in USA
Auto batteries: 99.2%
Office Type Papers: 70.9%
Yard Trimmings: 64.7%
Steel Cans: 62.8%
Aluminum Beer and Soft Drink Cans: 48.2%
Tires: 35.4%
HDPE Natural (White Translucent) Bottles: 29.3%
Glass Containers: 28.0%
PET Bottles and Jars: 27.2%
Benefits of Recycling
• USA recycled 83 million tons of MSW.
• This provides an annual benefit of 182 million
metric tons of carbon dioxide equivalent
emissions reduced,
• comparable to removing the emissions from
33 million passenger cars.
• But the ultimate benefits from recycling are
cleaner land, air, and water, overall better
health, and a more sustainable economy.
Municipal Waste
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On-site (at home)
Open Dump
Sanitary Landfill
Incineration
Ocean dumping
Open Dump
• Unsanitary, draws pests and vermin, harmful
runoff and leachates, toxic gases
• Still accounts for half of solid waste
• Several thousand open dumps in the USA
Sanitary Landfill
• Sanitary Landfill
– Layer of compacted trash covered with a layer of earth
once a day and a thicker layer when the site is full
– Require impermeable barriers to stop escape of leachates:
can cause problem by overflow
– Gases produced by decomposing garbage needs venting
– 1 acre/10,000 people: acute space problem: wastes piling
up over 150 million tons/year;
– # of landfills down from 8000(1988) to 3091(1996)
– NIMBY, NIMFYE, NIMEY, NOPE
– NJ ships >5 million tons of waste every year
Sanitary Landfill
• Avoid:
– Swampy area/ Flood plains /coastal areas
– Fractures or porous rocks
– High water table
• Prefer:
– Clay layers
– Heads of gullies
Monitoring of Sanitary Landfills
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Gases: Methane, Ammonia, Hydrogen sulphide
Heavy Metals: Lead, Chromium in soil
Soluble substances: chloride, nitrate, sulfate
Surface Run-offs
Vegetation: may pick up toxic substances
Plant residue in soil
Paper/plastics etc – blown by the wind
Incineration
• Solves space problem but:
– produces toxic gases like Cl, HCl, HCN, SO2
– High temp furnaces break down hazardous compounds but
are expensive ($75 - $2K/ton)
– Heat generated can be recovered: % of waste burnt
• Japan 67%, Switzerland 80%, USA 6%
– North Little Rock, AK saving $50K in heating cost and
reducing landfill requirement by 95%
– How many MSW combustors exist in the United States? In
1996, 110 combustors with energy recovery existed with the
capacity to burn up to 100,000 tons of MSW per day.
Ocean Dumping
• Out of sight, free of emission control norms
• Contributes to ocean pollution
• Can wash back on beaches, and can cause death of
marine mammals
• Preferred method: incineration in open sea
• Ocean Dumping Ban Act, 1988: bans dumping of
sewage sludge and industrial waste
• Dredge spoils still dumped in oceans, can cause
habitat destruction and export of fluvial pollutants
Reducing Waste
• Incineration, compacting
• Hog feed: requires heat treatment
• Composting: requires separation of organics from glass
and metals
• Recycling and Reusing
– Recycle of glass containers: 5 million tons
– Plastic: marked by types for easy recycling
– Converted into Fibers, trash bags, plastic lumber, fill for
pillows, insulation etc
– Junked cars: 150 – 200 kg of plastics: soon to be recycled
Municipal Waste
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•
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•
•
On-site (at home)
Open Dump
Sanitary Landfill
Incineration
Ocean dumping
Open Dump
• Unsanitary, draws pests and vermin, harmful
runoff and leachates, toxic gases
• Still accounts for half of solid waste
• Several thousand open dumps in the USA
Sanitary Landfill
• Sanitary Landfill
– Layer of compacted trash covered with a layer of earth
once a day and a thicker layer when the site is full
– Require impermeable barriers to stop escape of leachates:
can cause problem by overflow
– Gases produced by decomposing garbage needs venting
– 1 acre/10,000 people: acute space problem: wastes piling
up over 150 million tons/year;
– # of landfills down from 8000(1988) to 3091(1996)
– NIMBY, NIMFYE, NIMEY, NOPE
– NJ ships >5 million tons of waste every year
Sanitary Landfill
• Avoid:
– Swampy area/ Flood plains /coastal areas
– Fractures or porous rocks
– High water table
• Prefer:
– Clay layers
– Heads of gullies
Monitoring of Sanitary Landfills
•
•
•
•
•
•
•
Gases: Methane, Ammonia, Hydrogen sulphide
Heavy Metals: Lead, Chromium in soil
Soluble substances: chloride, nitrate, sulfate
Surface Run-offs
Vegetation: may pick up toxic substances
Plant residue in soil
Paper/plastics etc – blown by the wind
Incineration
• Solves space problem but:
– produces toxic gases like Cl, HCl, HCN, SO2
– High temp furnaces break down hazardous compounds but
are expensive ($75 - $2K/ton)
– Heat generated can be recovered: % of waste burnt
• Japan 67%, Switzerland 80%, USA 6%
– North Little Rock, AK saving $50K in heating cost and
reducing landfill requirement by 95%
– How many MSW combustors exist in the United States? In
1996, 110 combustors with energy recovery existed with the
capacity to burn up to 100,000 tons of MSW per day.
Ocean Dumping
• Out of sight, free of emission control norms
• Contributes to ocean pollution
• Can wash back on beaches, and can cause death of
marine mammals
• Preferred method: incineration in open sea
• Ocean Dumping Ban Act, 1988: bans dumping of
sewage sludge and industrial waste
• Dredge spoils still dumped in oceans, can cause
habitat destruction and export of fluvial pollutants
Reducing Waste
• Incineration, compacting
• Hog feed: requires heat treatment
• Composting: requires separation of organics from glass
and metals
• Recycling and Reusing
– Recycle of glass containers: 5 million tons
– Plastic: marked by types for easy recycling
– Converted into Fibers, trash bags, plastic lumber, fill for
pillows, insulation etc
– Junked cars: 150 – 200 kg of plastics: soon to be recycled
•In 1996, recycling of solid waste in the
United States prevented the release of
33 million tons of carbon into the air—
roughly the amount emitted annually by
25 million cars.
•1 ton of newspaper=18 trees, 3 m3 of
landfill, 60% less energy. Govt recycling
saving 223,000 tons, 4 million trees, $7.4
million
Auto
Steel
Aluminum Paper & Yard
Glass
Plastic
Tires Batteries Cans Packaging
Paperboard waste container
container
Recycling: facts and figures
• In 1999, recycling and composting activities prevented
about 64 million tons of material from ending up in
landfills and incinerators. Today, this country recycles 32
percent of its waste, a rate that has almost doubled during
the past 15 years.
• 50 percent of all paper, 34 percent of all plastic soft drink
bottles, 45 percent of all aluminum beer and soft drink
cans, 63 percent of all steel packaging, and 67 percent of
all major appliances are now recycled.
• Twenty years ago, only one curbside recycling program
existed in the United States, which collected several
materials at the curb. By 2005, almost 9,000 curbside
programs had sprouted up across the nation. As of 2005,
about 500 materials recovery facilities had been
established to process the collected materials.
Waste Exchange
• One persons waste can be another persons
raw material
• Fluorite from Al smelter in MD
• Isopropyl alcohol = cleaning solvent
• Nitric Acid from Electronic Industry = high
grade fertilizer
• Spent acid of steel industry = control for H2S
Liquid Waste
• Sewage
• Highly toxic Industrial Waste & Used Oil
– Dilute and Disperse
– Concentrate and Contain
– Secure Landfill
• Sealed drums to be put in impermeable holds with monitoring
wells to check for leakage: does not work
– Deep well Disposal
• Pumping in deep porous layer bounded by impermeable
formations, well below water table
• $1 million to drill, $15-20/ton afterwards
• Restricted by geological considerations, can trigger earthquakes
Story of Love Canal
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A ditch 20m wide, 3m deep and 1km long
1890: Built near Niagara falls for hydro-power
1905: Hooker Electrochemical established
1942: Hooker buys the site for waste disposal, 20,000 tons of toxic
chemical dumped in 10 yr
1953: site bought by Niagara School board for $1, Hooker absolved of any
future damage
1977: study shows toxic effects in adjoining homes,>40 toxic chemicals
identified
1978: Health advisory, 100 families to be shifted
1980: remedial measures taken, EPA study shows chromosome defects in
residents, President Carter declares emergency, provides federal aid
1981: Over 500 families moved out, hundreds waiting for aid
EPA estimate: 30,000 hazardous waste sites in US, only 10% of hazardous
wastes properly disposed, 300 million tons generated each year
•In 1996, recycling of solid waste in the
United States prevented the release of
33 million tons of carbon into the air—
roughly the amount emitted annually by
25 million cars.
•1 ton of newspaper=18 trees, 3 m3 of
landfill, 60% less energy. Govt recycling
saving 223,000 tons, 4 million trees, $7.4
million
Auto
Steel
Aluminum Paper & Yard
Glass
Plastic
Tires Batteries Cans Packaging
Paperboard waste container
container
Recycling: facts and figures
• In 1999, recycling and composting activities prevented
about 64 million tons of material from ending up in
landfills and incinerators. Today, this country recycles 32
percent of its waste, a rate that has almost doubled during
the past 15 years.
• 50 percent of all paper, 34 percent of all plastic soft drink
bottles, 45 percent of all aluminum beer and soft drink
cans, 63 percent of all steel packaging, and 67 percent of
all major appliances are now recycled.
• Twenty years ago, only one curbside recycling program
existed in the United States, which collected several
materials at the curb. By 2005, almost 9,000 curbside
programs had sprouted up across the nation. As of 2005,
about 500 materials recovery facilities had been
established to process the collected materials.
Waste Exchange
• One persons waste can be another persons
raw material
• Fluorite from Al smelter in MD
• Isopropyl alcohol = cleaning solvent
• Nitric Acid from Electronic Industry = high
grade fertilizer
• Spent acid of steel industry = control for H2S
Liquid Waste
• Sewage
• Highly toxic Industrial Waste & Used Oil
– Dilute and Disperse
– Concentrate and Contain
– Secure Landfill
• Sealed drums to be put in impermeable holds with monitoring
wells to check for leakage: does not work
– Deep well Disposal
• Pumping in deep porous layer bounded by impermeable
formations, well below water table
• $1 million to drill, $15-20/ton afterwards
• Restricted by geological considerations, can trigger earthquakes
Story of Love Canal
•
•
•
•
•
•
•
•
•
•
A ditch 20m wide, 3m deep and 1km long
1890: Built near Niagara falls for hydro-power
1905: Hooker Electrochemical established
1942: Hooker buys the site for waste disposal, 20,000 tons of toxic
chemical dumped in 10 yr
1953: site bought by Niagara School board for $1, Hooker absolved of any
future damage
1977: study shows toxic effects in adjoining homes,>40 toxic chemicals
identified
1978: Health advisory, 100 families to be shifted
1980: remedial measures taken, EPA study shows chromosome defects in
residents, President Carter declares emergency, provides federal aid
1981: Over 500 families moved out, hundreds waiting for aid
EPA estimate: 30,000 hazardous waste sites in US, only 10% of hazardous
wastes properly disposed, 300 million tons generated each year
Radioactive Waste Disposal
• Isotopes with short half-lives are gone quickly, those
with long half-lives will decay too little
• Low level wastes: 90% of all radioactive wastes
– 20 temporary and 6 commercial disposal sites
– States to take care of their low level waste
• High level wastes e.g., spent nuclear fuel rods
– Should be so disposed as to cause less than 1000 death in
10,000 years
High Level Waste Depository
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Rocketing to sun
Under Antarctica Ice sheet
Subduction Zone
Sea bed disposal
Bedrock caverns
– Granites, basalt, tuff, shale, salt caverns
– Salt: High melting point, impermeable in dry condition,
self-sealing, cheap resource
• No permanent high level waste repository yet
Requirements for a radio-active
waste disposal system
• Design and Fabricate a System that will
– Last thousands of years longer than recorded
human history
– Be robust enough to isolate highly radioactive
material so that it will not threaten human health
and environment for more than ten thousand
years.
Story of Yucca Mountain Site
• 1982: Nuclear Waste Policy Act
– Congress charges DOE with the task
– Two high level waste depository in the eastern and the
western USA
– Billions collected from tax on utilities
• 1986: Hanford, Wa, Yucca Mtn, Ne and Deaf
Smith County, Tx shortlisted as western sites
• 1987: Congress suddenly decides on Nevada
(screw Nevada bill)
– Read about “Screw Nevada Bill”
– Nevada to receive $20 million/year
• Feb 15, 2002: Pres. Bush approved Yucca Mtn as
the site for high level nuclear waste respository
Yucca Mountain Site
• Geologically stable (?)
– Limited fault displacement
– No volcanism in 10,000 years
• Tuff host rock, 1000 ft below the surface, 1000 ft
above the water table
• Arid climate, no streams, low water table
• Low population density
• Federally owned land, close to Nevada test sites