Waste Disposal

1
Waste Disposal

• Chapter 15

2
Some Facts

• In 1996, U.S. residents, businesses, and
  institutions produced more than 209 million
  
  tons of MSW, which is approximately 4.3 pounds of
  waste per person per day, up from 2.7 pounds per
  person per day in 1960 mass of Statue of
  Liberty every 5 years
• United States
• has 8 of world population
• Consume 1/3rd of Worlds resources
• Produces ½ of Worlds garbage

3
Handled on site
Not toxic
Not toxic
Areas of concern
4
1991 data
Paper 50
5
(No Transcript)
6
Municipal Waste

• Open Dump
• Sanitary Landfill
• Incineration
• Ocean dumping

7
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

8
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 gt5 million tons of waste every year

9
(No Transcript)
10
(No Transcript)
11
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.

12
(No Transcript)
13
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

14
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

15

• In 1996, recycling of solid waste in the United
  States prevented the release of 33 million tons
  of carbon into the airroughly the amount emitted
  annually by 25 million cars.
• 1 ton of newspaper18 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
16
(No Transcript)
17
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

18
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

19
(No Transcript)
20
(No Transcript)
21
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,gt40 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

22
Sewage Treatment

• Individual scale
• Settling tank (solids settle and are broken down)
• Leaching field receives liquids from septic tank
  through porous pipes. Bacteria and oxygen breaks
  down organics and disease causing germs
• Should have soil layer 60 cm below 150cm above
• Should not be within 15m of any water body
• 0.5 to 1 acre per dwelling

23
(No Transcript)
24
Municipal Sewage Treatment

• 75 of US population served by sewage system and
  lt5 releases untreated sewage
• Primary treatment removal of solids
• Secondary treatment biological
• Bacteria and fungi breaks down organics
• Chlorinated to kill germs, can form chloroform
  which is carcinogenic
• Tertiary treatment Filtration and chemical
  treatment expensive
• Sludge is a by-product and is rich in organics
  and nutrients

25
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

26
High Level Waste Depository

• 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

27
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.

28
(No Transcript)
29
(No Transcript)
30
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)
• Nevada to receive 20 million/year
• Feb 15, 2002 Pres. Bush approved Yucca Mtn as
  the site for high level nuclear waste respository

31
(No Transcript)
32
(No Transcript)
33
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