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Title: Waste and Recycling Notes Waste Disposal


1
Waste and Recycling Notes Waste Disposal
2
Electronic Waste A Growing Problem
  • E-waste consists of toxic and hazardous waste
    such as PVC, lead, mercury, and cadmium.
  • The U.S. produces almost half of the world's
    e-waste but only recycles about 10 of it.

Figure 22-4
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7
Chapter Overview Questions
  • What is solid waste and how much do we produce?
  • How can we produce less solid waste?
  • What are the advantages and disadvantages of
    reusing recycled materials?
  • What are the advantages and disadvantages of
    burning or burying solid waste?
  • What is hazardous waste and how can we deal with
    it?

8
Chapter Overview Questions (contd)
  • What can we do to reduce exposure to lead and
    mercury?
  • How can we make the transition to a more
    sustainable low-waste society?

9
Core Case Study Love Canal There Is No Away
  • Between 1842-1953, Hooker Chemical sealed
    multiple chemical wastes into steel drums and
    dumped them into an old canal excavation (Love
    Canal).
  • In 1953, the canal was filled and sold to Niagara
    Falls school board for 1.
  • The company inserted a disclaimer denying
    liability for the wastes.

10
Core Case Study Love Canal There Is No Away
  • In 1957, Hooker Chemical warned the school not to
    disturb the site because of the toxic waste.
  • In 1959 an elementary school, playing fields and
    homes were built disrupting the clay cap covering
    the wastes.
  • In 1976, residents complained of chemical smells
    and chemical burns from the site.

11
Core Case Study Love Canal There Is No Away
  • President Jimmy Carter declared Love Canal a
    federal disaster area.
  • The area was abandoned in 1980 (left).

Figure 22-1
12
Core Case Study Love Canal There Is No Away
  • It still is a controversy as to how much the
    chemicals at Love Canal injured or caused disease
    to the residents.
  • Love Canal sparked creation of the Superfund law,
    which forced polluters to pay for cleaning up
    abandoned toxic waste dumps.

13
Early Concepts of Waste Disposal
  • Start of Industrial Revolution, the volume of
    waste produced in the US was relatively small.
  • Managed through the concept of dilute and
    disperse.
  • Factories located near water.
  • Easy transport of materials by boat
  • Sufficient water for processing and cooling
  • Easy disposal of waste into the river
  • Few factories and a sparse population
  • Method was sufficient to remove the waste from
    the immediate environment.

14
Early Concepts of Waste Disposal
  • As industrial and urban areas expanded, the
    concept became concentrate and contain
  • Containment not always achieved.
  • Containers leak or break and allow waste to
    escape.
  • People are facing a serious solid-waste disposal
    problem.
  • We are producing a great deal of waste and the
    acceptable space for permanent disposal is
    limited.
  • Difficult to site new landfills (NIMBY).

15
Modern Trends
  • Environmentally correct concept is to consider
    wastes as resources out of place.
  • Waste would be a resource to be used again.
  • Referred to as the zero waste movement.
  • Industrial ecology
  • Study of relationships among industrial systems
    and their links to natural systems.
  • Waste from one part of the system would be a
    resource for another part.

16
Modern Trends
  • Countries have moved to cut waste by imposing
    taxes.
  • Taxation of waste in all its various forms, from
    emissions from smokestacks to solids delivered to
    landfills.
  • As taxes increase people produce less waste.
  • Landfills produce methane gas which can be burned
    as fuel.

17
Integrated Waste Management
  • A set of management alternatives that includes
  • Reuse
  • Source reduction
  • Recycling
  • Composting
  • Landfill
  • Incineration

18
Reduce, Reuse, Recycle
  • Ultimate objective of the three Rs is to reduce.
  • Study of the waste stream in areas that utilize
    IWM technology suggests that the amount of refuse
    disposed of in landfills or incinerated can be
    reduced by at least 50
  • Reduction facilitated by
  • Better design of packaging to reduce waste, an
    element of source reduction (10 reduction).
  • Large-scale composting programs (10 reduction).
  • Establishment of recycling programs (30
    reduction).

19
Reduce, Reuse, Recycle
  • Recycling is a major player in the reduction of
    urban waste stream.
  • Estimated that as much as 80-90 of the US waste
    stream might be recovered through intense
    recycling.
  • Partial recycling can provide a significant
    reduction 50.
  • Simplified by single stream recycling.

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21
Public Support for Recycling
  • Encouraging signs
  • An increase in the willingness of industry and
    business to support recycling on a variety of
    scales.
  • People are now more likely to purchase products
    that can be recycled or that come in containers
    that are more easily recycled or composted.

22
How does the public feel about recycling?
23
Markets for Recycled Products
  • In communities where recycling has been
    successfully implemented, it has resulted in
    glutted markets for the recycled products.
  • If recycling is to be successful,
  • markets and processing facilities will also have
    to be developed to ensure that recycling is a
    sound financial venture.

24
Recycling of Human Waste
  • The use of human waste or night soil on
    croplands is an ancient practice.
  • Early uses of human waste for agriculture
    occasionally spread infectious diseases.
  • One of the major problems of recycling human
    waste today is that thousands of chemicals and
    metals flow through our waste stream.
  • Because many toxic materials are likely to be
    present with the waste, we must be very skeptical
    of utilizing sewage sludge for land application.

25
Materials Management
  • Futuristic waste management has the goal of zero
    production of waste.
  • Consistent with the ideals of industrial ecology.
  • Goal will require more sustainable use of
    materials combined with resource conservation in
    what is being termed materials management.

26
Materials Management
  • The goal could be pursued in the following ways
  • Eliminate subsidies for extraction of virgin
    materials.
  • Establish green building incentives that
    encourage the use of recycled-content materials
    and products in new construction.
  • Assess financial penalties for production that
    uses negative materials management practices.

27
Materials Management
  • Provide financial incentives for industrial
    practices and products that benefit the
    environment by enhancing sustainability.
  • Increase the number of new jobs in the technology
    of reuse and recycling of resources.

28
Composition of Solid Waste
  • Paper is by far the most abundant content.
  • Excavations into modern landfills using
    archeological tools have cleared up some
    misconceptions concerning other items.
  • Fast-food packaging accounts for about 0.25 of
    the average landfill
  • Disposable diapers, approximately 0.8
  • Polystyrene products, about 0.9

29
Solid-Waste Management
  • Continues to be a problem in many parts of the
    world.
  • Many practices inadequate.
  • Open dumps, illegal roadside dumping
  • Social problem as much as a physical one, because
    many people are simply disposing of their waste
    as inexpensively and as quickly as possible.

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31
On-Site Disposal
  • A common on-site disposal method in urban areas
    is the mechanical grinding of kitchen food waste.
  • Garbage-disposal devices are installed at the
    kitchen sink, and the garbage is ground and
    flushed into the sewer system.

32
Composting
  • Biochemical process in which organic materials
    decompose to a rich, soil-like material.
  • The process involves rapid partial decomposition
    of moist solid organic waste by aerobic
    organisms.
  • As a waste management option, large-scale
    composting is generally carried out in the
    controlled environment of mechanical digesters.

33
Incineration
  • Combustible waste is burned at temperatures high
    enough (9001,000C, or 1,6501,830F) to
    consume all combustible material.
  • Leaving only ash and non-combustibles to dispose
    of in a landfill.
  • Process of incineration can be used to supplement
    other fuels and generate electrical power.
  • In modern incineration facilities, smokestacks
    are fitted with special devices to trap
    pollutants.

34
Open Dumps
  • In the past, solid waste was often disposed of in
    open dumps, where the refuse was piled up without
    being covered or otherwise protected.
  • Located wherever land is available, without
    regard to safety, health hazards, or aesthetic
    degradation.
  • Common sites
  • Abandoned mines and quarries, natural low areas,
    such as swamps or floodplains and hillside areas
    above or below towns.

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36
Sanitary Landfills
  • Designed to concentrate and contain refuse w/o
    creating a nuisance or hazard to public health or
    safety.
  • Confined to the smallest practical area
  • Reduced to the smallest practical volume
  • Covered with a layer of compacted soil at the end
    of each day of operation.

37
Leachate
  • The most significant hazard from a sanitary
    landfill is pollution of groundwater or surface
    water.
  • If waste comes into contact with water, leachate
    is produced.
  • noxious, mineralized liquid capable of
    transporting bacterial pollutants

38
WASTING RESOURCES
  • Solid waste any unwanted or discarded material
    we produce that is not a liquid or gas.
  • Municipal solid waste (MSW) produce directly
    from homes.
  • Industrial solid waste produced indirectly by
    industries that supply people with goods and
    services.
  • Hazardous (toxic) waste threatens human health
    or the environment because it is toxic,
    chemically active, corrosive or flammable.

39
WASTING RESOURCES
  • Solid wastes polluting a river in Jakarta,
    Indonesia. The man in the boat is looking for
    items to salvage or sell.

Figure 22-3
40
WASTING RESOURCES
  • The United States produces about a third of the
    worlds solid waste and buries more than half of
    it in landfills.
  • About 98.5 is industrial solid waste.
  • The remaining 1.5 is MSW.
  • About 55 of U.S. MSW is dumped into landfills,
    30 is recycled or composted, and 15 is burned
    in incinerators.

41
Definition
Landfills
  • Solid waste is placed in a hole, compacted, and
    covered with soil.
  • Reduces the number of rats associated with solid
    waste, lessens the danger of fire, and decreases
    the odor.

42
Current Criteria
  • Landfills cannot pollute surface or groundwater.
  • Compacted clay and plastic sheets are at the
    bottom (prevents liquid waste from seeping into
    groundwater)
  • A double liner system must be present (plastic,
    clay, plastic, clay), and a system to collect
    leachate (liquid that seeps through the solid
    waste)

43
Oil
  • Not allowed
  • Must go to an automotive or environmental company
    for recycling.

44
Tires
  • Are usually allowed if they are quartered or
    shredded.

45
Antifreeze
  • Not allowed.
  • Must be sent to an automotive or environmental
    company for recycling.

46
Air Conditioner Coolants
  • Not allowed
  • Must be sent to an automotive or environmental
    company for recycling.

47
Lead Acid (Car Batteries)
  • Not allowed
  • Must be sent to an automotive or an environmental
    company for recycling.

48
Definition
Compost
  • A sweet-smelling, dark-brown, humus-like material
    that is rich in organic material and soil
    nutrients.

49
Benefits
  • Aerates the soil.
  • Improves soils ability to retain water and
    nutrients.
  • Helps prevent erosion.
  • Prevents nutrients from being dumped in landfills.

50
Definition
Recycling
  • Conservation of resources by converting them into
    new product.

51
Organic
  • Comprise over 1/2 of the solid waste
  • Includes yard debris, wood materials, bio-solids,
    food, manure and agricultural residues, land
    clearing debris, used paper, and mixed municipal
    organic waste.
  • Organic materials have been dumped in landfills
    or burned. Why not use them!

52
General Purpose
  • Recycling saves land, reduces the amount of solid
    waste, energy consumption and pollution.
  • Ex. recycling one aluminum can saves the energy
    of about 6 oz. of gasoline.

53
Examples
  • Gold, lead, nickel, steel, copper, silver, zinc,
    and aluminum are recyclable.

54
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55
Problems
  • Recycling does have environmental costs.
  • It uses energy and generates pollution.
  • Ex. the de-inking process in paper recycling
    requires energy, and produces a toxic sludge that
    contains heavy metals.

56
Benefits
  • Conserves our natural resources
  • Has a positive effect on the economy by
    generating jobs and revenues.
  • For example, the Sunday edition of the New York
    Times consumes 62,000 trees.
  • Currently, only about 20 of all paper in North
    America is recycled.

57
Specific Recycled Items
58
Glass
  • U.S. recycles about 36 of its glass containers.
  • It costs less to recycle glass than to make new
    glass.
  • Mixed color glass cullet is used for
    glassphalt, a glass/asphalt mixture.

59
Aluminum
  • This is the most recycled material in the U.S.
    because of .
  • Making a new can from an old one requires a
    fraction of the energy than to make a new can
    from raw materials.
  • Approximately 2/3 of cans are recycled each year,
    saving 19 million barrels of oil annually.

60
Paper
  • U.S. currently recycles 40 of its paper and
    paperboard.
  • Denmark, recycles about 97 of its paper.
  • Many U.S. mills are not able to process waste
    paper.
  • Many countries like Mexico, import a large amount
    of wastepaper from the U.S.
  • We export about 19 of our recycled paper.

61
Recyclable Plastics
62
1 - PET (Polyethylene terephthalate)
  • PET is used to make soft drink bottles, peanut
    butter jars, etc.
  • PET can be recycled into fiberfill for sleeping
    bags, carpet fibers, rope, and pillows.

63
2 - HDPE (High-density polyethylene)
  • HDPE is found in milk jugs, butter tubs,
    detergent bottles, and motor oil bottles.
  • HDPE can be recycled into flowerpots, trashcans,
    traffic barrier cones, and detergent bottles.

64
3 - PVC (Polyvinyl chloride)
  • PVC is used in shampoo and cooking oil bottles
    fast-food service items.

65
4 - LDPE (Low-density polyethylene)
  • LDPE is found in grocery bags, bread bags,
    shrink-wrap, and margarine tub tops.
  • LDPE can be recycled into new grocery bags.

66
5 - PP (Polypropylene)
  • PP is used in yogurt containers, straws, pancake
    syrup bottles, and bottle caps.
  • PP can be recycled into plastic lumber, car
    battery cases, and manhole steps.

67
6 - PS (Polystyrene)
  • PS is found in disposable hot cups, packaging
    materials (peanuts), meat trays.
  • PS can be recycled into plastic lumber, cassette
    tape boxes, and flowerpots.

68
7 - Other
  • A mixture of various plastics, like squeeze
    ketchup bottles microwaveable dishes.

69
Nuclear Waste
  • The safe disposal of radioactive wastes is the
    problem.
  • Radioactive wastes must be stored in an isolated
    area where they cant contaminate the
    environment.
  • It must have geological stability and little or
    no water flowing nearby.

70
Texas Production of Waste
  • The TNRCC oversees the municipal waste in Texas.
  • In 1998, the solid waste disposal rate for Texans
    was 6.5 pounds per person per day.
  • This is based on every item that goes into a
    landfill.
  • The TNRCC estimates that 12,740,234 tons were
    diverted for recycling in 1998.
  • Texans disposal rate is comparable to the US
    disposal rate.

71
Packaging
  • Many packaging items are put into landfills,
    including boxes, packing peanuts, Styrofoam,
    shrink wrap, etc.
  • Try to buy things that are not as highly
    packaged.
  • Many companies use peanuts that are made from
    cellulose that can be washed down the drain and
    not put into landfills.
  • Reuse containers and buy smart!

72
Definition
Integrated Waste Management
  • The most effective way to deal with solid and
    hazardous waste and hazardous waste.
  • This includes the three Rs reduce, reuse, and
    recycle.

73
INTEGRATED WASTE MANAGEMENT
  • We can manage the solid wastes we produce and
    reduce or prevent their production.

74

Second Priority
Last Priority
First Priority
Primary Pollution and Waste Prevention
Waste Management
Secondary Pollution and Waste Prevention
Treat waste to reduce toxicity
Change industrial process to eliminate
use of harmful chemicals
Reuse products
Repair products
Incinerate waste
Bury waste in landfills
Recycle
Purchase different products
Compost
Release waste into environment for
dispersal or dilution
Buy reusable recyclable products
Use less of a harmful product
Reduce packaging and materials in products
Make products that last longer and are
recyclable, reusable, or easy to repair
Fig. 22-5, p. 523
75
Solutions Reducing Solid Waste
  • Refuse to buy items that we really dont need.
  • Reduce consume less and live a simpler and less
    stressful life by practicing simplicity.
  • Reuse rely more on items that can be used over
    and over.
  • Repurpose use something for another purpose
    instead of throwing it away.
  • Recycle paper, glass, cans, plasticsand buy
    items made from recycled materials.

76

What Can You Do?
Solid Waste
  • Follow the five Rs of resource use
    Refuse,
    Reduce,
  • Reuse, Repurpose, and Recycle.

Ask yourself whether you really need a
particular item.
Rent, borrow, or barter goods and services when
you can.
Buy things that are reusable, recyclable, or
compostable, and be sure to reuse, recycle, and
compost them.
Do not use throwaway paper and plastic plates,
cups and eating utensils, and other disposable
items when reusable or refillable versions are
available.
Refill and reuse a bottled water container with
tap water.
Use e-mail in place of conventional paper mail.
Read newspapers and magazines online.
Buy products in concentrated form whenever
possible.
Fig. 22-6, p. 524
77
REUSE
  • Reusing products is an important way to reduce
    resource use, waste, and pollution in developed
    countries.
  • Reusing can be hazardous in developing countries
    for poor who scavenge in open dumps.
  • They can be exposed to toxins or infectious
    diseases.

78
RECYCLING
  • Primary (closed loop) recycling materials are
    turned into new products of the same type.
  • Secondary recycling materials are converted into
    different products.
  • Used tires shredded and converted into rubberized
    road surface.
  • Newspapers transformed into cellulose insulation.

79
RECYCLING
  • Composting biodegradable organic waste mimics
    nature by recycling plant nutrients to the soil.
  • Recycling paper has a number of environmental
    (reduction in pollution and deforestation, less
    energy expenditure) and economic benefits and is
    easy to do.

80
RECYCLING
  • Recycling many plastics is chemically and
    economically difficult.
  • Many plastics are hard to isolate from other
    wastes.
  • Recovering individual plastic resins does not
    yield much material.
  • The cost of virgin plastic resins in low than
    recycled resins due to low fossil fuel costs.
  • There are new technologies that are making
    plastics biodegradable.

81
BURNING AND BURYING SOLID WASTE
  • Globally, MSW is burned in over 1,000 large
    waste-to-energy incinerators, which boil water to
    make steam for heating water, or space, or for
    production of electricity.
  • Japan and a few European countries incinerate
    most of their MSW.

82
Waste-to-Energy Incineration
  • 1) the volume of waste is reduced by up to 90
    and 2) the heat produced, produces steam, which
    can warm buildings or generate electricity.
  • In 1999, the U.S. had 110 w-to-e incinerators,
    which burned 16 of the nations solid waste
    produces less CO2 emissions than power plants
    that run on fossil fuels. Giant piles of tires
    are also being burned to supply electricity.

83
Burning Solid Waste
  • Waste-to-energy incinerator with pollution
    controls that burns mixed solid waste.

Figure 22-10
84
Burying Solid Waste
  • Most of the worlds MSW is buried in landfills
    that eventually are expected to leak toxic
    liquids into the soil and underlying aquifers.
  • Open dumps are fields or holes in the ground
    where garbage is deposited and sometimes covered
    with soil. Mostly used in developing countries.
  • Sanitary landfills solid wastes are spread out
    in thin layers, compacted and covered daily with
    a fresh layer of clay or plastic foam.

85

When landfill is full, layers of soil and
clay seal in trash
Topsoil
Electricity generator building
Sand
Clay
Methane storage and compressor building
Leachate treatment system
Garbage
Probes to detect methane leaks
Pipes collect explosive methane as used as fuel
to generate electricity
Methane gas recovery well
Leachate storage tank
Compacted solid waste
Groundwater monitoring well
Garbage
Leachate pipes
Leachate pumped up to storage tank for safe
disposal
Sand
Synthetic liner
Leachate monitoring well
Clay and plastic lining to prevent leaks
pipes collect leachate from bottom of landfill
Sand
Clay
Groundwater
Subsoil
Fig. 22-12, p. 532
86
Case Study What Should We Do with Used Tires?
  • We face a dilemma in deciding what to so with
    hundreds of millions of discarded tires.

Figure 22-14
87
HAZARDOUS WASTE
  • Hazardous waste is any discarded solid or liquid
    material that is toxic, ignitable, corrosive, or
    reactive enough to explode or release toxic
    fumes.
  • The two largest classes of hazardous wastes are
    organic compounds (e.g. pesticides, PCBs,
    dioxins) and toxic heavy metals (e.g. lead,
    mercury, arsenic).

88
Hazardous Waste Regulations in the United States
  • Two major federal laws regulate the management
    and disposal of hazardous waste in the U.S.
  • Resource Conservation and Recovery Act (RCRA)
  • Cradle-to-the-grave system to keep track waste.
  • Comprehensive Environmental Response,
    Compensation, and Liability Act (CERCLA)
  • Commonly known as Superfund program.
  • You must know these two laws!

89
Hazardous Waste Regulations in the United States
  • The Superfund law was designed to have polluters
    pay for cleaning up abandoned hazardous waste
    sites.
  • Only 70 of the cleanup costs have come from the
    polluters, the rest comes from a trust fund
    financed until 1995 by taxes on chemical raw
    materials and oil.

90
Conversion to Less Hazardous Substances
  • Physical Methods using charcoal or resins to
    separate out harmful chemicals.
  • Chemical Methods using chemical reactions that
    can convert hazardous chemicals to less harmful
    or harmless chemicals.

91
Conversion to Less Hazardous Substances
  • Biological Methods
  • Bioremediation bacteria or enzymes help destroy
    toxic and hazardous waste or convert them to more
    benign substances.
  • Phytoremediation involves using natural or
    genetically engineered plants to absorb, filter
    and remove contaminants from polluted soil and
    water.

92

Inorganic metal contaminants
Organic contaminants
Radioactive contaminants
Poplar tree
Brake fern
Willow tree
Sunflower
Indian mustard
Landfill
Oil spill
Polluted groundwater in
Polluted leachate
Decontaminated water out
Soil
Soil
Groundwater
Groundwater
Phytodegradation Plants such as poplars can
absorb toxic organic chemicals and break them
down into less harmful compounds which they
store or release slowly into the air.
Rhizofiltration Roots of plants such as
sunflowers with dangling roots on ponds or in
green- houses can absorb pollutants such as
radioactive strontium-90 and cesium-137 and
various organic chemicals.
Phytoextraction Roots of plants such as Indian
mustard and brake ferns can absorb toxic metals
such as lead, arsenic, and others and store
them in their leaves. Plants can then be
recycled or harvested and incinerated.
Phytostabilization Plants such as willow trees
and poplars can absorb chemicals and keep them
from reaching groundwater or nearby surface water.
93

Inorganic metal contaminants
Organic contaminants
Radioactive contaminants
Poplar tree
Brake fern
Willow tree
Sunflower
Indian mustard
Landfill
Oil spill
Polluted groundwater in
Polluted leachate
Decontaminated water out
Soil
Soil
Groundwater
Groundwater
Phytodegradation
Rhizofiltration
Phytostabilization
Phytoextraction
94

Inorganic metal contaminants
Organic contaminants
Radioactive contaminants
Poplar tree
Brake fern
Willow tree
Sunflower
Indian mustard
Landfill
Oil spill
Polluted groundwater in
Polluted leachate
Decontaminated water out
Soil
Soil
Groundwater
Groundwater
Rhizofiltration Roots of plants such as
sunflowers with dangling roots on ponds or in
green-houses can absorb pollutants such as
radioactive strontium-90 and cesium-137 and
various organic chemicals.
95

Inorganic metal contaminants
Organic contaminants
Radioactive contaminants
Poplar tree
Brake fern
Willow tree
Sunflower
Indian mustard
Landfill
Oil spill
Polluted groundwater in
Polluted leachate
Decontaminated water out
Soil
Soil
Groundwater
Groundwater
Phytostabilization Plants such as willow trees
and poplars can absorb chemicals and keep them
from reaching groundwater or nearby surface water.
96

Inorganic metal contaminants
Organic contaminants
Radioactive contaminants
Poplar tree
Brake fern
Willow tree
Sunflower
Indian mustard
Landfill
Oil spill
Polluted groundwater in
Polluted leachate
Decontaminated water out
Soil
Soil
Groundwater
Groundwater
Phytodegradation Plants such as poplars can
absorb toxic organic chemicals and break them
down into less harmful compounds which they
store or release slowly into the air.
97

Inorganic metal contaminants
Organic contaminants
Radioactive contaminants
Poplar tree
Brake fern
Willow tree
Sunflower
Indian mustard
Landfill
Oil spill
Polluted groundwater in
Polluted leachate
Decontaminated water out
Soil
Soil
Groundwater
Groundwater
Phytoextraction Roots of plants such as Indian
mustard and brake ferns can absorb toxic metals
such as lead, arsenic, and others and store them
in their leaves. Plants can then be recycled or
harvested and incinerated.
98
Conversion to Less Hazardous Substances
  • Incineration heating many types of hazardous
    waste to high temperatures up to 2000 C in
    an incinerator can break them down and convert
    them to less harmful or harmless chemicals.

99
Conversion to Less Hazardous Substances
  • Plasma Torch passing electrical current through
    gas to generate an electric arc and very high
    temperatures can create plasma.
  • The plasma process can be carried out in a torch
    which can decompose liquid or solid hazardous
    organic material.

100
Long-Term Storage of Hazardous Waste
  • Hazardous waste can be disposed of on or
    underneath the earths surface, but without
    proper design and care this can pollute the air
    and water.
  • Deep-well disposal liquid hazardous wastes are
    pumped under pressure into dry porous rock far
    beneath aquifers.
  • Surface impoundments excavated depressions such
    as ponds, pits, or lagoons into which liners are
    placed and liquid hazardous wastes are stored.

101
Long-Term Storage of Hazardous Waste
  • Long-Term Retrievable Storage Some highly toxic
    materials cannot be detoxified or destroyed.
    Metal drums are used to stored them in areas that
    can be inspected and retrieved.
  • Secure Landfills Sometimes hazardous waste are
    put into drums and buried in carefully designed
    and monitored sites.

102
Secure Hazardous Waste Landfill
  • In the U.S. there are only 23 commercial
    hazardous waste landfills.

Figure 22-22
103
ACHIEVING A LOW-WASTE SOCIETY
  • In the U.S., citizens have kept large numbers of
    incinerators, landfills, and hazardous waste
    treatment plants from being built in their local
    areas.
  • Environmental justice means that everyone is
    entitled to protection from environmental hazards
    without discrimination.

104
Global Outlook International Action to Reduce
Hazardous Waste
  • An international treaty calls for phasing out the
    use of harmful persistent organic pollutants
    (POPs).
  • POPs are insoluble in water and soluble in fat.
  • Nearly every person on earth has detectable
    levels of POPs in their blood.
  • The U.S has not ratified this treaty.

105
Making the Transition to a Low-Waste Society A
New Vision
  • Everything is connected.
  • There is no away for the wastes we produce.
  • Dilution is not always the solution to pollution.
  • The best and cheapest way to deal with wastes are
    reduction and pollution prevention.
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