Ch 21 Waste

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LIVING IN THE ENVIRONMENT, 18e
G. TYLER MILLER • SCOTT E. SPOOLMAN
21
Solid and Hazardous Waste
©©Cengage
CengageLearning
Learning2015
2015
Core Case Study: E-Waste – An Exploding
Problem
• Electronic waste (e-waste) is the fastest
growing solid waste problem
• Most ends up in landfills and incinerators
• Composition includes:
– High-quality plastics
– Valuable metals
– Toxic and hazardous pollutants
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Core Case Study: E-Waste – An Exploding
Problem (cont’d.)
• Shipped to other countries
• International Basel Convention
– Bans transferring hazardous wastes from
developed countries to developing countries
• European Union
– Cradle-to-grave approach
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Fig. 21-1, p. 576
21-1 What Are Solid Waste and Hazardous
Waste, and Why Are They Problems?
• Solid waste contributes to pollution and
includes valuable resources that could be
reused or recycled
• Hazardous waste contributes to pollution,
as well as to natural capital degradation,
health problems, and premature deaths
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We Throw Away Huge Amounts of Useful
Things
• Solid waste
– Industrial solid waste
• Mines, farms, industries
– Municipal solid waste (MSW)
• Trash
• Waste ends up in:
– Rivers, lakes, the ocean, and natural
landscapes
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Hazardous Waste Is a Serious and
Growing Problem
• Hazardous waste (toxic waste)
– Threatens human health of the environment
• Classes of hazardous waste
– Organic compounds
– Toxic heavy metals
– Radioactive waste
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Case Study: Solid Waste in the United
States
• Leader in solid waste problem
– In trash production, by weight, per person
• 98.5% of all solid waste is industrial waste
• Most wastes break down very slowly
– If at all
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Fig. 21-5, p. 579
21-2 How Should We Deal with Solid
Waste?
• A sustainable approach to solid waste is:
– First to reduce it
– Then to reuse or recycle it
– Finally, to safely dispose of what is left
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We Can Burn, Bury, or Recycle Solid
Waste or Produce Less of It
• Waste management
– Reduce harm, but not amounts
• Waste reduction
– Use less and focus on reuse, recycle,
compost
• Integrated waste management
– Uses a variety of strategies
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Raw materials
Processing
and
manufacturing
Products
Solid and hazardous
wastes generated
during the
manufacturing process
Waste generated
by households
and businesses
Plastic Glass Metal Paper
To manufacturers for reuse
or for recycling
Food/yard
waste
Hazardous
waste
Remaining
mixed waste
Compost
Hazardous waste
management
Landfill
Incinerator
Fertilizer
© Cengage Learning 2015
Fig. 21-6, p. 581
We Can Cut Solid Wastes by Refusing,
Reducing, Reusing, and Recycling
• Waste reduction is based on:
– Refuse – don’t use it
– Reduce – use less
– Reuse – use it over and over
– Recycle
• Composting
– Using bacteria to decompose biodegradable
waste
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Refusing, Reducing, Reusing, and
Recycling (cont’d.)
• Six strategies:
– Change industrial processes to eliminate
harmful chemicals
– Redesign manufacturing process to use less
material and energy
– Develop products that are easy to recycle
– Eliminate unnecessary packaging
– Use fee-per-bag waste collection systems
– Establish cradle-to grave responsibility
© Cengage Learning 2015
What We Should Do
What We Do
Reduce
Bury (67%)
Reuse
Recycle/Compost (23.7%)
Recycle/Compost
Incinerate (9%)
Incinerate
Reuse (0.2%)
Bury
Reduce
(<0.1%)
© Cengage Learning 2015
Fig. 21-7, p. 581
21-3 Why Are Refusing, Reducing,
Reusing, and Recycling So Important?
• By refusing and reducing resource use
and by reusing and recycling what we use,
we:
– Decrease our consumption of matter and
energy resources
– Reduce pollution and natural capital
degradation
– Save money
© Cengage Learning 2015
There Are Alternatives to the Throwaway
Economy
• We increasingly substitute throwaway
items for reusable ones
• In general, reuse is on the rise
• One solution: taxing plastic shopping bags
– Ireland, Taiwan, the Netherlands
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Fig. 21-11, p. 583
There Is Great Potential for Recycling
• Primary, closed-loop recycling
– Materials recycled into same type
• Secondary recycling
– Materials converted to other products: tires
• Types of wastes that can be recycled
– Preconsumer, internal waste generated in
manufacturing process
– Postconsumer, external waste generated by
product use
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There Is Great Potential for Recycling
(cont’d.)
• With incentives, the U.S. could recycle and
compost 80% of its municipal solid waste
• Composting
– Mimics nature’s recycling of nutrients
– Resulting organic matter can be used to:
• Supply plant nutrients
• Slow soil erosion
• Retain water
• Improve crop yield
© Cengage Learning 2015
We Can Mix or Separate Household Solid
Wastes for Recycling
• Materials-recovery facilities (MRFs)
– Can encourage increased trash production
• Source separation
– Pay-as-you-throw
– Fee-per-bag
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Recycling Paper
• Production of paper versus recycled paper
– Energy use – world’s fifth largest consumer
– Water use
– Pollution
• Easy to recycle
– Uses 64% less energy
– Produces 35% less water pollution
– Produces 74% less air pollution
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Recycling Plastics
• Plastics
– Composed of resins created from oil and
natural gas
• Currently only 7% is recycled in the U.S.
– Many types of plastic resins
– Difficult to separate
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Recycling Has Advantages and
Disadvantages
• Advantages
– Net economic health
– Environmental benefits
• Disadvantages
– Costly
• Single-pickup system
– No separation needed
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Trade-Offs
Recycling
Advantages
Disadvantages
Reduces energy
and mineral use
and air and water
pollution
Can cost more than
burying in areas with
ample landfill space
Reduces
greenhouse
gas emissions
Reduces profits for
landfill and
incinerator owners
Reduces solid waste
Inconvenient for
some
© Cengage Learning 2015
Fig. 21-14, p. 585
21-4 The Advantages and Disadvantages
of Burning or Burying Solid Waste
• Technologies for burning and burying solid
wastes are well developed
– However, burning contributes to air and water
pollution and greenhouse gas emissions, and
buried wastes eventually contribute to the
pollution and degradation of land and water
resources
© Cengage Learning 2015
Burning Solid Waste Has Advantages and
Disadvantages
• Waste-to-energy incinerators
– To heat water or produce electricity
• Landfills emit more air pollutants than
modern waste-to-energy incinerators
– Toxic chemicals that are filtered must be
disposed of or stored
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Electricity
Smokestack
Furnace
Boiler
Waste
pit
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Ash for treatment,
disposal in landfill, or
use as landfill cover Fig. 21-15, p. 588
Trade-Offs
Waste-to-Energy Incineration
Advantages
Disadvantages
Reduces trash
volume
Expensive to build
Produces energy
Produces a
hazardous waste
Concentrates
hazardous
substances into
ash for burial
Emits some CO2 and
other air pollutants
Sale of energy
reduces cost
Encourages waste
production
Fig. 21-16, p. 588
Burying Solid Waste Has Advantages and
Disadvantages
• Sanitary landfills
– Compacted layers of waste between clay or
foam
– Bottom liners; containment systems
• Open dumps
– Widely used in less-developed countries
• Rare in developed countries
– Large pit
• Sometimes garbage is burned
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Topsoil
When landfill is full, layers
of soil and clay seal in trash
Sand
Clay
Garbage
Probes to
detect
methane
leaks
Electricity
generator
building
Methane
storage and
compressor
building
Methane gas
recovery
well
Leachate
treatment system
Pipes collect
explosive methane
for use as fuel
to generate
electricity
Leachate
storage
tank
Compacted
solid waste
Garbage
Sand
Synthetic
liner
Sand
Clay
Subsoil
Leachate
pipes
Leachate pumped
up to storage tank
for safe disposal
Groundwater
Clay and plastic lining to
prevent leaks; pipes collect
leachate from bottom of landfill
Groundwater
monitoring
well
Leachate
monitoring
well
Fig. 21-17, p. 589
Trade-Offs
Sanitary Landfills
Advantages
Disadvantages
Low operating
costs
Noise, traffic,
and dust
Can handle large
amounts of waste
Releases greenhouse
gases (methane and
CO2) unless they are
collected
Filled land can
be used for
other purposes
Output approach that
encourages waste
production
No shortage of
landfill space in
many areas
Eventually leaks and
can contaminate
groundwater
© Cengage Learning 2015
Fig. 21-18, p. 589
21-5 How Should We Deal with Hazardous
Waste?
• A more sustainable approach to
hazardous waste:
– First, produce less of it
– Then, reuse or recycle it
– Then, convert it to less-hazardous materials
– Finally, safely store what is left
© Cengage Learning 2015
We Can Use Integrated Management of
Hazardous Waste
• Integrated management of hazardous
wastes
– Produce less
– Convert to less hazardous substances
– Rest in long-term safe storage
• Increased use for postconsumer
hazardous waste
© Cengage Learning 2015
Produce Less
Hazardous Waste
Convert to Less Hazardous or
Nonhazardous Substances
Put in
Perpetual Storage
Change industrial processes
to reduce or eliminate
hazardous waste production
Natural decomposition
Landfill
Incineration
Underground injection wells
Recycle and reuse hazardous
waste
Thermal treatment
Surface impoundments
Chemical, physical, and biological
treatment
Underground salt formations
Dilution in air or water
Stepped Art
Fig. 21-20, p. 591
Case Study: Recycling E-Waste
• 70% goes to China
– Hazardous working conditions
– Includes child workers
• U.S. produces roughly 50% of the world’s
e-waste
– Recycles only 14%
© Cengage Learning 2015
We Can Detoxify Hazardous Wastes
• Collect and then detoxify
– Physical methods
– Chemical methods
– Use nanomagnets
– Bioremediation
– Phytoremediation
• Incineration
• Using a plasma arc torch
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Radioactive
contaminants
Sunflower
Landfill
Polluted
groundwater
Decontaminated
in
Soil
water out
Groundwater
Rhizofiltration
Roots of plants such
as sunflowers with
dangling roots on ponds
or in greenhouses
can absorb pollutants
such as radioactive
strontium-90 and
cesium-137 and various
organic chemicals.
Inorganic
metal contaminants
Brake fern
Indian
mustard
Organic
contaminants
Poplar tree
Willow tree
Phytostabilization
Plants such as
willow trees and
poplars can absorb
chemicals and keep
them from reaching
groundwater or
nearby surface
water.
Oil
spill
Polluted
leachate
Phytodegredation
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.
Soil
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.
Fig. 21-22, p. 593
We Can Store Some Forms of Hazardous
Waste
• Burial on land or long-term storage
– Last resort only
• Deep-well disposal
– 64% of hazardous liquid wastes in the U.S.
• Surface impoundments
– Lined pools for evaporation
• Secure hazardous waste landfills
– Expensive
© Cengage Learning 2015
Trade-Offs
Deep-Well Disposal
Advantages
Disadvantages
Safe if sites are
chosen carefully
Leaks from corrosion
of well casing
Wastes can often
be retrieved
Emits CO2 and
other air pollutants
Low cost
Output approach that
encourages waste
production
© Cengage Learning 2015
Fig. 21-24, p. 594
Trade-Offs
Surface Impoundments
Advantages
Disadvantages
Low cost
Water pollution
from leaking liners
and overflows
Wastes can often
be retrieved
Air pollution from
volatile organic
compounds
Can store wastes
indefinitely with
secure double
liners
Output approach that
encourages waste
production
© Cengage Learning 2015
Fig. 21-26, p. 594
© Cengage Learning 2015
Fig. 21-28, p. 595
Case Study: Hazardous Waste Regulation
in the United States
• 1976 – Resource Conservation and
Recovery Act (RCRA)
– EPA sets standards and gives permits
– Cradle to grave
– Covers only 5% of hazardous wastes
© Cengage Learning 2015
Case Study: Hazardous Waste Regulation
in the United States (cont’d.)
• 1980 – Comprehensive Environmental,
Compensation, and Liability Act (CERCLA)
– National Priorities List
• 2013 – 1320 Superfund sites; 365 cleaned
– Pace of cleanup has slowed
– Superfund is broke
• Laws encouraging the cleanup of
brownfields
– Abandoned industrial sites
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Fig. 21-29, p. 596
21-6 How Can We Make the Transition to
a More Sustainable Low-Waste Society?
• Shifting to a low-waste society requires
individuals and businesses to:
– Reduce resource use
– Reuse and recycle wastes at local, national,
and global levels
© Cengage Learning 2015
Grassroots Action Has Led to Better Solid
and Hazardous Waste Management
• Prevent construction of:
– Incinerators, landfills, treatment plants,
polluting chemical plants
• Something must be done with hazardous
wastes
© Cengage Learning 2015
Providing Environmental Justice for
Everyone Is an Important Goal
• Environmental justice
– Everyone is entitled to protection from
environmental hazards
• Which communities in the U.S. have the
largest share of hazardous waste dumps?
• Environmental discrimination
© Cengage Learning 2015
We Can Encourage Reuse and Recycling
• Factors that hinder reuse and recycling:
– Market prices do not include harmful costs
– Economic playing field is uneven
– Demand for recycled products fluctuates
• Governments can pass laws requiring
companies to reuse and recycle
© Cengage Learning 2015
Reuse, Recycling, and Composting
Present Economic Opportunities
• Freecycle network
• Upcycling
– Recycling materials into products of higher
value
• Dual-use packaging
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International Treaties Have Reduced
Hazardous Waste
• Basel Convention
– 1992 – in effect
– 1995 amendment – bans all transfers of
hazardous wastes from industrialized
countries to less-developed countries
– 2012 – ratified by 179 countries, but not the
United States
© Cengage Learning 2015
International Treaties Have Reduced
Hazardous Waste (cont’d.)
• 2000 – delegates from 122 countries
completed a global treaty
– Control 12 persistent organic pollutants
(POPs)
– DDT, PCBs, dioxins
– Everyone on earth has POPs in blood
• 2000 – Swedish Parliament law
– By 2020 ban all chemicals that are persistent
and can accumulate in living tissue
© Cengage Learning 2015
We Can Make the Transition to Low-Waste
Societies
• Norway, Austria, and the Netherlands
– Committed to reduce resource waste by 75%
• Key principles
– Everything is connected
– There is no away
– Producers and polluters should pay
– We can mimic nature by recycling and
composting
© Cengage Learning 2015
Case Study: Industrial Ecosystems:
Copying Nature
• Resource exchange webs
– Waste as raw material
– Ecoindustrial parks
• Two major steps of biomimicry
– Observe how natural systems respond
– Apply to human industrial systems
© Cengage Learning 2015
Three Big Ideas
• The order of priorities for dealing with solid
waste should be to:
– Produce less of it
– Reuse and recycle as much of it as possible
– Safely burn or bury what is left
© Cengage Learning 2015
Three Big Ideas (cont’d.)
• The order of priorities for dealing with
hazardous waste should be to:
– Produce less of it
– Reuse or recycle it
– Convert it to less hazardous material
– Safely store what is left
© Cengage Learning 2015
Three Big Ideas (cont’d.)
• View solid wastes as wasted resources,
and hazardous wastes as materials that
we should not be producing in the first
place
© Cengage Learning 2015
Tying It All Together: E-Waste and
Sustainability
• Reduce outputs of solid hazardous waste
• Mimic nature’s chemical cycling process
– Reuse and recycle
• Integrated waste management
• Include harmful environmental and health
costs in market prices
© Cengage Learning 2015
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