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Solid and Hazardous Waste
Chapter 22
Essential Question #1
What is solid waste, and how much do we
produce?
Solid Waste• Any unwanted or discarded solid material
– There is no solid waste in nature
– Garbage = solid waste we produce directly
What did you throw away yesterday?
Types of Solid Waste• Municipal Solid Waste (MSW)
– Produced directly by homes and workplaces (“garbage”)
– 1.5% of Solid Waste in U.S.
• Industrial Waste– Produced indirectly by mines, factories,
refineries, food growers, and businesses that supply goods & services
– 98.5% of Solid Waste in U.S.
Municipal1.5%
Sewage sludge1%
Mining and oiland gas
production75%
Industry9.5%
Agriculture13%
The U.S. Produces 1/3 of the World’s Solid Waste!!!
Hazardous WasteWaste that threatens human health or the
environment because it is toxic, chemically active, corrosive or flammable
•Developed countries produce 80-90%
Why Should We Care?• Unnecessary waste of resources
• Production of solid products leads to ALL other forms of pollution!
What Happens to MSW in the U.S.?
• 55% goes to Landfills
• 30% is Recycled / Composted
• 15% is Burned / Incinerated
Electronic Waste: The Fastest Growing Waste Problem
• E-waste consists of toxic and hazardous waste such as PVC, PBB/PBOE, lead, mercury, and cadmium.
• The U.S. produces almost half of the world's e-waste but only recycles about 10% of it.
Cradle-to-Grave Standards
• European Union (EU) requires manufacturers to take back electronic products & bans e-waste in MSW.
• Minnesota has curbside recycling for e-waste
Washington requires manufacturers to pay for cost of collection, transportation & recycling
Essential Question #2
What is integrated waste management and how can it help produce less solid
waste?
Waste Management & Reduction
• Waste Management– Bury it or Burn it– High-waste approach
• Waste Reduction– There is no “away”– Low-waste approach– Preferred solution (prevention)
Fig. 22-5, p. 523
Primary Pollutionand Waste Prevention
First Priority Second Priority Last Priority
• Release waste into environment for dispersal or dilution
• Bury waste in landfills
Waste Management
• Incinerate waste
• Buy reusable recyclable products
• Recycle
• Repair products
• Make products that last longer and are recyclable, reusable, or easy to repair
• Reduce packaging and materials in products
• Redesign manufacturing processes and products to use less material and energy
Secondary Pollution and Waste Prevention
• Treat waste to reduce toxicity
• Consume Less / Purchase different (less harmful) products
• Reuse products
• Change industrial process to eliminate use of harmful (toxic) chemicals
• Compost
Integrated Waste ManagementIntegrated Waste Management
Ecoindustrial Revolution• A change in industrial manufacturing to be cleaner
and more sustainable (mimics how nature handles waste)
– Use less material & energy / produce less waste & pollution
– Savings can be enormous
– Resource exchange web – waste of one manufacturer becomes raw materials for another
– Healthier work environment
Selling Services Instead of Things
• Eco-leasing – instead of buying a product, a customer would lease/rent the services from the company
Example – RHS has a service contract for our copiers. They are maintained regularly. They will be picked up by the company at the end of the contract and reusable parts will be removed.
PAYT / Fee-per-bag Systems
• PAYT – Pay as you Throw– Consumers pay only for trash, not recyclable
materials
Cradle-to-Grave Laws• Require manufacturers to take back consumer
products after usefulness
• Encourages companies to create longer lasting, more easily repairable products
The 5 “R’s” for Reducing Waste• Refuse:
– to buy items that we really don’t 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, plastics…and buy items made from recycled
materials.
• Follow the five Rs of resource use: Refuse, Reduce, Reuse, Repurpose, and Recycle.
• Buy products in concentrated form whenever possible.
• Read newspapers and magazines online.
• Use e-mail in place of conventional paper mail.
• Refill and reuse a bottled water container with tap water.
• Do not use throwaway paper and plastic plates, cups and eating utensils, and other disposable items when reusable or refillable versions are available.
• Buy things that are reusable, recyclable, or compostable, and be sure to reuse, recycle, and compost them.
• Rent, borrow, or barter goods and services when you can.
• Ask yourself whether you really need a particular item.
What Can You Do?
Solid Waste
The Story of Stuff
• http://www.storyofstuff.org/movies-all/story-of-stuff/
Essential Question #3
What are the advantages and disadvantages or reusing and recycling
materials?
Reuse
• Cleaning & using materials over & over
• Examples of Reusable Items:– eating utensils– car parts– house and building materials– cloth towels & diapers– rechargeable batteries– TVs, computers, cell phones– glass and plastic bottles– grocery bags– clothing
Pros & Cons: Reuse
Advantages
• Saves Money
• Cuts pollution & waste
• Reduces use of matter & energy resources
Disadvantages
• Exposure to toxins in e-waste (developing countries)
• People scavenging for reuseable materials in dumps exposed to toxins & disease
Energy consumption for different types of 350-ml (12-oz) beverage
containers.
Bottle Laws
• Consumers pay a small deposit on reusable or recyclable beverage containers
• Deposit is refunded when item returned to store for reuse or recycling
Fig. 22-8, p. 526
• Buy beverages in refillable glass containers instead of cans or throwaway bottles.
• Give or sell items you no longer use to others.
• Buy used furniture, computers, cars, and other items.
• Use reusable sponges and washable cloth napkins, dishtowels, and handkerchiefs instead of throwaway paper ones.
• Carry groceries and other items in a reusable basket, a canvas or string bag, or a small cart.
• Use rechargeable batteries and recycle them when their useful life is over.
• Carry sandwiches and store food in the refrigerator in reusable containers instead of wrapping them in aluminum foil or plastic wrap
• Use reusable plastic or metal lunchboxes.
What Can You Do?
Reuse
Recycling
• Reprocessing discarded solid materials into new, useful products
• Examples of Recyclable Items:– paper products– glass– aluminum– steel– some plastics– plants (composting)
2 Recycling Methods
• Primary (Closed-Loop) Recycling– Original Same
• Secondary Recycling (Downcycling)– Original Different
PromLadies?
Prom Fellas? Maybe not…
MRF’s vs. Source Separation
• Materials Recovery Facility (MRF)– All waste goes to one facility– Machines or workers sort out valuable materials– Expensive to build & operate– Produces toxic ash & air pollution
• Source Separation– Wastes separated by consumer– Less air/water pollution– Lower cost & more jobs
Composting
Using nature to recycle biodegradable organic waste (yard waste, food scraps)
Used as organic fertilizer, topsoil, filler on eroded or overgrazed land
Benefits of Recycling Paper
• Environmental– Reduces pollution– Reduces deforestation– Less energy required
• Economic– Generates jobs– Economic growth
• Easy to do!
Recycling Plastics• 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 is lower than recycled resins due to
low fossil fuel costs.
• Exception is PET (polyethylene terephthalate)– Used for most plastic drink bottles– Can be remanufactured into fleece, polyester, carpet, packaging,
etc
There are new technologies that are making plastics biodegradable.
• Plant based bioplastics
Pros & Cons: RecyclingAdvantages
• Less pollution
• Saves energy
• Saves raw materials
• Less landfill space
• Saves money on products
• Creates jobs
• Reduces litter
Disadvantages• Some materials are costly to
recycle
• Some areas have ample landfill space
• Landfills lose money
• Inconvenient for some
• If we don’t buy recycled products, recycling doesn’t work
Fig. 22-9, p. 529
Important part of economy
Source separation is inconvenient for some people
Reduces profits from landfills and incinerators
Reduces air and water pollution
Saves energy
Reduces mineral demand
Reduces greenhouse gas emissions
Reduces solid waste production and disposal
Helps protect biodiversity
Can save money for items such as paper, metals, and some plastics
Does not save landfill space in areas with ample land
May lose money for items such as glass and most plastic
DisadvantagesAdvantages
Trade-Offs
Recycling
Essential Question #4
What are the advantages and disadvantages of
burning or burying solid waste?
Crane
Hazardouswaste landfill
Wastetreatment
Conventionallandfill
Wastepit Bottom
ash
Fly ashConveyor
Wateradded Dirty
water
Furnace Wetscrubber
Electrostaticprecipitator
Boiler
Smokestack
Electricity
Steam Turbine
Generator
Waste-to-Energy Incinerator
Pros & Cons: BurningAdvantages
• Reduces waste
• Fast
• Produces energy (electricity) / sale of energy reduces cost
• Modern controls can reduce air pollution
Disadvantages
• Expensive to build
• Air pollution
• Toxic ash remains
• Highly opposed in US
Fig. 22-11, p. 531
Reduces trash volume
Can compete with recycling for burnable materials such as newspaper
Output approach that encourages waste production
Older or poorly managed facilities can release large amounts of air pollution
Some air pollution
Difficult to site because of citizen opposition
Costs more than short-distance hauling to landfills
Expensive to build
Some facilities recover and sell metals
Modern controls reduce air pollution
Sale of energy reduces cost
Concentrates hazardous substances into ash for burial or use as landfill cover
Low water pollution
Less need for landfills
Trade-Offs
Incineration
Advantages Disadvantages
Burying• According to EPA, all landfills will eventually leak.
• Open Dumps– Common in developing nations
• Sanitary Landfills– Used in developed countries– Wastes spread in thin layers & covered w/ clay or plastic
foam, lined to prevent leaks
Topsoil
Sand
Clay
Garbage
Garbage
Sand
Syntheticliner
Sand
Clay
Subsoil
When landfill is full,layers of soil and clayseal in trash
Methane storageand compressorbuilding
Electricitygeneratorbuilding
Leachatetreatment system
Methane gasrecovery
Pipe collect explosivemethane gas used as fuel to generate electricity
Compactedsolid waste
Leachatestorage tank
Leachatemonitoringwell
Groundwatermonitoringwell
Leachate pipes Leachate pumped upto storage tanks forsafe disposal
Clay and plastic liningto prevent leaks; pipescollect leachate frombottom of landfill
Probes to detect methane leaks
Groundwater
Sanitary Landfill
Pros & Cons: BuryingAdvantages
• Low odor• Low groundwater pollution• Low cost to build & operate• Holds large amount• Ample sites in some areas• Can be reused when full
Disadvantages
• Noisy & dusty• Greenhouse gas emissions
(CH4, CO2)• Air pollution (toxic gas /
VOC’s)• Eventually leaks –
groundwater contamination• Slow decomposition• Cheap cost discourages
reuse & recycle
No open burning
Trade-Offs
Sanitary Landfills
Advantages Disadvantages
Eventually leaks and can contaminate groundwater
Discourages recycling, reuse, and waste reduction
Slow decompositionof wastes
Groundwater contamination
Releases greenhouse gases (methane and CO2)unless they are collected
Air pollution from toxic gases and volatile organiccompounds
Dust
Noise and traffic
No shortage of landfill space in many areas
Filled land can be used for other purposes
Can handle large amounts of waste
Can be built quickly
Low operating costs
Low groundwaterpollution if sited properly
Little odor
Essential Question #5
What is hazardous waste and how can we deal
with it?
Hazardous Waste• Any discarded solid or liquid material that is
toxic, ignitable, corrosive or reactive enough to explode or release toxic fumes
• Two Largest Classes– Organic Compounds
• PCB’s, Dioxins, pesticides, & various solvents
– Toxic Heavy Metals• Lead, Mercury, Arsenic, Cadmium
© 2006 Brooks/Cole - Thomson
What Harmful Chemicals Are In Your Home?
Cleaning • Disinfectants• Drain, toilet, and window cleaners • Spot removers• Septic tank cleaners
Paint
• Latex and oil-based paints• Paint thinners, solvents, and strippers • Stains, varnishes, and lacquers• Wood preservatives• Artist paints and inks
General• Dry-cell batteries (mercury and cadmium)• Glues and cements
Gardening
• Pesticides• Weed killers• Ant and rodent killers• Flea powders
Automotive
• Gasoline• Used motor oil • Antifreeze• Battery acid• Solvents• Brake and transmission fluid• Rust inhibitor and rust remover
Harmful Chemicals in Your Home
Disposal of some of these items is exempt from government regulation
Managing Hazardous Waste• Resource Conservation & Recovery Act (RCRA)
• EPA– Sets standards, issues permits & monitors management
• Cradle-to-Grave– Permit holders must track hazardous waste from point of
generation (cradle) to approved disposal (grave)– Proof must be submitted to EPA– All phases subject to unannounced EPA inspection
Cleaning-up Hazardous Waste• Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA /Superfund)
– Identifies & cleans hazardous waste sites on a priority basis (National Priorities List – NPL)
– Designed to make polluters pay for cleaning
– 70% of clean-up costs have come from polluters & rest has come from the Superfund
• Trust fund financed until 1995 by taxes on chemical raw materials & oil
– Congress refused to renew Superfund in 1995, now taxpayers cover cost of clean-ups when responsible parties cannot be found
Love Canal• 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.
• 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.
• 1980 President Jimmy Carter declared Love Canal a federal disaster area.
Dealing with Hazardous Waste
We can produce less hazardous waste and recycle, reuse, detoxify, burn, and bury what we continue to
produce.
• Physical Methods– Uses filters, distillation and precipitation to remove harmful
chemicals from waste
• Chemical Methods– Uses chemical reactions to detoxify waste– Ex: cyclodextrin & nanomagnets
• Biological Methods– Bioremediation (bacteria & enzymes) & phytoremediation (plants)
• Incineration– Heating to high temperatures (3,600°F) / produces toxic ash
• Plasma Torch– Uses plasma to incinerate at higher temps (18,000°F) / no ash
Detoxifying Hazardous Waste
PhytostabilizationPlants such as willow trees and poplars can absorb chemicals and keep them from reaching groundwater or nearby surface water.
RhizofiltrationRoots 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.
PhytoextractionRoots 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.
PhytodegradationPlants such as poplarscan absorb toxic organic chemicals and break them down into less harmful compounds which they store or release slowly into the air.
Inorganicmetal contaminants
Organiccontaminants
Radioactivecontaminants
Brake fernPoplar tree Indian mustardWillow treeSunflower
Oilspill
Landfill
Groundwater
SoilPollutedleachate
Decontaminatedwater out
Pollutedgroundwater in
Groundwater
Soil
Inexpensive
Low energy use
Easy to establish
Trade-Offs
Phytoremediation
Advantages Disadvantages
Some plants can become toxic to animals
Some toxic organic chemicals may evaporate from plant leaves
Produces little air pollution compared to incineration
Can reduce material dumped into landfills
Slow (can take several growing seasons)
Effective only at depth plant roots can reach
Fig. 22-19, p. 538
Advantages
Trade-Offs
Plasma Arc
Small High cost
Produces no toxic ash
Can vaporize and release toxic metals and radioactive elements
Can release particulates and chlorine gas
Mobile. Easy to move to different sites
Produces CO2 and CO
Disadvantages
Hazardous Waste Storage
• Deep Underground Wells– Pumped deep below ground
• Surface Impoundments– Stored in containment ponds
• Long-Term Retrievable Storage– Stored in metal drums in carefully designed &
monitored aboveground buildings
• Secure Hazardous Waste Landfills– Stored in drums & buried
Safe method ifsites are chosencarefully
Trade-Offs
Deep Underground Wells
Advantages Disadvantages
Encourageswaste production
Existing fracturesor earthquakescan allow wastesto escape intogroundwater
Leaks fromcorrosion of wellcasing
Leaks or spills atsurface
Low cost
Easy to do
Wastes can beretrieved ifproblemsdevelop
Low construction costs
Can store wastes indefinitely with secure double liners
Groundwatercontaminationfrom leaking liners(or no lining)
Trade-Offs
Surface Impoundments
Advantages
Promotes wasteproduction
Disruption andleakage fromearthquakes
Overflow fromflooding
Air pollution fromvolatile organiccompounds
Wastes can be retrieved if necessary
Can be built quickly
Low operating costs
Disadvantages
What Can You Do?
• Use pesticides in the smallest amount possible.
• Use less harmful substances instead of commercial chemicals for most household cleaners. For
example use liquid ammonia to clean appliances and windows; vinegar to polish metals, clean surfaces, and remove stains and mildew; baking soda to clean household utensils, deodorize, and remove stains; borax to
remove stains and mildew.• Do not dispose of pesticides, paints, solvents, oil,
antifreeze, or other products containing hazardous chemicals by flushing them down the toilet, pouring them down the drain, burying them, throwing them into the garbage, or dumping them down storm drains.
Hazardous Waste
Essential Question #6
How have lead and mercury become problems in our
environment, why are they dangerous and what can
we do to reduce exposure?
Lead and Mercury
Since they are both elements, they cannot be broken down
Both cause various types of nervous system damage (brain damage)
Lead
• Lead is especially harmful to children and is still used in leaded gasoline and household paints in about 100 countries.
Lead Exposure Solutions• Eliminate leaded gasoline &
paint worldwide (banned in late ’70’s in U.S.)
• Eliminate lead solder in plumbing & food cans
• Remove lead paint from old buildings
• Replace plumbing pipes containing lead
Mercury
• Mercury is released into the environment mostly by burning coal and incinerating wastes and can build to high levels in some types of fish.
Mercury Exposure
• Mercury comes from natural (volcanos) & human sources (burning coal / waste)– We can breath, absorb & consume it
• Solutions:– Eliminate Hg in coal, batteries, fluorescent bulbs– Avoid eating certain seafood (shark, mackerel, tuna)
esp children & women– Reduce Hg emissions from coal burning plants
Biomagnification
Minamata Story
• https://www.youtube.com/watch?v=ihFkyPv1jtU
Essential Question #7
How can we make the transition to a more
sustainable, low-waste society ?
Achieving a Low Waste Society• Produce less wastes of all kinds
• Reduce our ecological footprint
• International treaties to ban or phase out use of certain highly toxic, fat soluble (stores up in organisms) Persistent Organic Pollutants (POP’s) such as DDT, PCB, dioxins, & furans
• Basel Convention - international treaty bans shipping of hazardous waste to developing countries (U.S. not a member)
Achieving a Low Waste Society
• REMEMBER:
– Everything is connected
– There is no “AWAY” for the wastes we produce
– Dilution is NOT the solution for pollution
– The BEST & CHEAPEST way to deal w/ waste & pollution is to produce less and recycle more