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ENVIRONMENTAL SCIENCE
CHAPTER 16:Solid and
Hazardous Waste
Core Case Study: Electronic Waste
• What is electronic waste or e-waste?
• Fastest growing category of waste• ____% recyclable• Contains toxic materials
Fig. 16-1, p. 403
Wasting Resources (1)
• Solid Waste• Industrial solid waste
______________________________________________________
• Municipal solid waste ____________________________________
Wasting Resources (2)
• Hazardous or toxic waste– Threatens human health or environment– Poisonous– Reactive– Corrosive– Flammable– Developed countries produce ________%
Wasting Resources (3)
• Solid waste and hazardous waste– About ____ unnecessary resource waste– Create air & water pollution,
land degradation
What Harmful Chemicals Are in Your Home?
CleaningDisinfectantsDrain, toilet, and window cleanersSpot removersSeptic tank cleaners
Paint ProductsPaints, stains, varnishes, and lacquersPaint thinners, solvents, and strippers
Wood preservativesArtist paints and inks
GardeningPesticidesWeed killersAnt and rodent killersFlea powders
GeneralDry-cell batteries (mercury and cadmium)
Glues and cements
AutomotiveGasolineUsed motor oilAntifreezeBattery acidBrake and transmission fluid
Stepped ArtFig. 16-2, p. 405
Fig. 16-3, p. 405
Case Study:Solid Waste in the United States
• Produces ____ of world’s solid waste• Mining, agricultural, industrial: _____%• Municipal solid waste: _____%• High-waste economy• Examples?
sustainable approach to solid waste
• Waste management
• Waste reduction–reduce it!
• Integrated waste management–then reuse or recycle it–& safely dispose of what is left
Fertilizer
CompostHazardous waste
management Landfill
Hazardouswaste
Remainingmixed waste
To manufacturers for reuse orfor recycling
Processing andmanufacturing
Plastic Glass PaperFood/yard
waste
Solid and hazardouswastes generated during
the manufacturing process
Waste generated byhouseholds and
businesses
Products
Raw materials
Metal
Incinerator
Fig. 16-4, p. 407
Last Priority
Waste Management
Treat waste to reduce toxicity
Incinerate waste
Bury waste in landfills
Release waste into environment for dispersal or dilution
Stepped Art
Second Priority
Second Pollution and Waste Prevention
Reuse
Repair
Recycle
Compost
Buy reusable and recyclable products
First Priority
Primary Pollution and Waste Prevention
Change industrial process to eliminate use of harmful chemicals
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. 16-5, p. 407
Fig. 16-6, p. 408
Science Focus: Garbology
• Garbologists• Like archaeologists • Trash persists for decades
Why Is Reusing and Recycling Materials So Important?
Reusing items: • decreases use of matter & energy resources• reduces pollution & natural capital degradation • recycling does so to a lesser degree
Reuse
• Reuse as a form of waste reduction• Salvaging• Yard sales, flea markets, secondhand
stores, auctions, newspaper ads, Craigslist, ebay
• Technology: rechargeable batteries• Refillable containers and cloth bags
Fig. 16-7, p. 409
5 major types of materials can be recycled1. ________________________
2. ________________________
3. ________________________
4. ________________________
5. ________________________
Recycling
• Primary (closed-loop) recycling• Secondary recycling• Pre-consumer (internal) waste• Post-consumer (external) waste• Feasibility and marketing
Mixed vs Separate Household Recycling
• Material recovery facilities (MRF)
___________________________• Source separation
– By households and businesses– ___________________________________
___________________________________
Composting
• Decomposing bacteria• Household composting• Organic waste collection facilities• Successful large-scale composting
Individuals Matter: Recycling Plastics
• _____% plastics recycled• MBA Polymers, Inc – commercial
recycling process– Mike Biddle and Trip Allen, co-founders
• Pellets cheaper than virgin plastics• More environmentally friendly
Fig. 16-8, p. 411
Trade-Offs
RecyclingAdvantages DisadvantagesReduces air and waterpollution
Saves energy
Reduces mineral demand
Reduces greenhouse gas emissions
Reduces solid wasteproduction and disposal
Helps protect biodiversity
Can save landfill space
Important part of economy
Can cost more thanburying in areas withample landfill space
May lose money for items such as glass and some plastics
Reduces profits for landfill and incinerator owners
Source separation isinconvenient for somepeople
Science Focus: Bioplastics
• Most plastics are organic polymers produced from petrochemicals
• Bioplastics made from plant materials• Biodegradable
– Composting
Encouraging Reuse & Recycling
• Market prices must reflect true costs• Even economic playing field:
_____________________________• Stabilize prices for recycled materials• _______________________________• ______________________________
Boiler
Wetscrubber
Dirtywater
BottomashConveyor
Wateradded
Furnace
Steam Turbine
Generator
Smokestack
Electricity
Electrostaticprecipitator
Ash for treatment,disposal in landfill, oruse as landfill cover
Fly ash
Wastepit
Crane
Fig. 16-9, p. 413
Fig. 16-10, p. 414
Trade-OffsIncineration
Advantages DisadvantagesReduces trashvolume
Less need forlandfills
Low waterpollution
Concentrateshazardoussubstances intoash for burial
Sale of energyreduces cost
Modern controlsreduce airpollution
Some facilitiesrecover and sellmetals
Expensive to build
Costs more thanshort-distance hauling to landfills
Difficult to site becauseof citizen opposition
Some air pollution andCO2 emissions
Older or poorly managed facilities can release large amounts of air pollution
Output approach thatencourages wasteproduction
Can compete withrecycling for burnablematerials such asnewspaper
Burying Solid Wastes
• Open dumps• Sanitary landfills• Leachates
Clay and plastic liningto prevent leaks; pipescollect leachate frombottom of landfill
GroundwaterLeachatemonitoringwell
GroundwatermonitoringwellLeachate pumped
up to storage tankfor safe disposal
Leachate pumpedup to storage tankfor safe disposal
Leachatestoragetank
Leachatestoragetank
Leachatetreatment system
Pipes collect explosivemethane for use as fuelto generate electricity
Pipes collect explosivemethane for use as fuelto generate electricity
Electricitygeneratorbuilding
When landfill is full,layers of soil and clayseal in trash
Methane storageand compressorbuilding
Methane gasrecovery wellMethane gasrecovery well
Compactedsolid waste
Leachatepipes
Leachatepipes
Probes todetectmethaneleaks
Topsoil
Garbage
ClaySand
Garbage
Subsoil
Synthetic liner
SandClay
Sand
Fig. 16-11, p. 414
Fig. 16-12, p. 415
Trade-Offs
Sanitary LandfillsAdvantages Disadvantages
No open burning Noise and traffic
No shortage of landfill spacein many areas
Filled land can be used forother purposes
Eventually leaks and cancontaminate groundwater
Output approach thatencourages waste production
Slow decomposition of wastes
Releases greenhouse gases(methane and CO2) unlessthey are collected
Air pollution from toxic gasesand trucks
Dust
Can handle large amountsof waste
Low operating costs
Can be built quickly
Low groundwater pollutionif sited properly
Little odor
Put inPerpetual Storage
Landfill
Underground injection wells
Surface impoundments
Underground salt formations
Stepped Art
Convert to Less Hazardous or Nonhazardous Substances
Natural decomposition
Incineration
Thermal treatment
Chemical, physical, and biological treatment
Dilution in air or water
Produce Less Hazardous Waste
Change industrial processes to reduce or eliminate hazardous waste production
Recycle and reuse hazardous waste
Fig. 16-13, p. 415
Integrated hazardous waste management
Detoxifying Hazardous Waste
• Bioremediation• Phytoremediation• Incineration• Plasma arc torch
Storing Hazardous Waste
• Deep-well disposal__________________________________________
• Surface impoundments– ______ % in U.S. have _______________________– ______ % may threaten ______________________
• Secure landfills
Fig. 16-14, p. 417
Fig. 16-15, p. 417
Trade-Offs
Surface Impoundments
Advantages Disadvantages
Wastes can oftenbe retrieved ifnecessary
Groundwatercontamination fromleaking liners (or nolining)
Low constructioncosts
Low operatingcosts
Can be builtquickly
Can store wastesindefinitely withsecure doubleliners
Output approach thatencourages wasteproduction
Disruption and leakage from earthquakes
Air pollution fromvolatile organiccompoundsOverflow fromflooding
Leakdetectionsystem
Groundwatermonitoringwell
Reactivewastesin drums
Plasticdoubleliner
Watertable
Earth
Double leachatecollection system
Groundwater
Claycap
Imperviousclay cap
Plastic cover
imperviousclay
Bulkwaste
Gasvent
Topsoil
EarthSand
Fig. 16-16, p. 418
Fig. 16-17, p. 418
Hazardous Waste Regulation in USA
• Resource Conservation & Recovery Act– EPA administers– Cradle to grave
• Laws regulate only ____% of hazardous wastes
Superfund– 1980 - created– Cleans hazardous waste sites– Nov. 2008: 1,255 sites on list; 322 sites
cleaned– Now broke– Who pays for clean up?
Brownfields– Turning toxic areas into parks and
nature reserves
Dealing with Lead (Pb) Poisoning
• Neurotoxin• Especially harmful to children
– 1976-2004: # children with unsafe blood Pb levels dropped from
_____% to _____%– Gov’t banned ________________________
____________________________________
• _____ countries still use leaded gasoline
Fig. 16-18, p. 419
Solutions
Lead PoisoningPrevention ControlPhase outleaded gasolineworldwide
Phase out wasteincineration
Ban use of leadsolder
Ban use of leadin computer andTV monitors
Ban lead glazingfor ceramicwareused to servefood
Test blood forlead by age 1
Replace lead pipesand plumbing fixtures containing lead solder
Wash fresh fruits and vegetables
Test existing candles for lead
Test for lead in existing ceramic-ware used to serve food
Remove lead from TV sets and computermonitors beforeincineration or land disposal
Sharply reduce lead emissions from incinerators
Remove leaded paint and lead dust from older houses and apartments
Ban candles withlead cores
Achieving a Low-Waste Society
• Grassroots action• Environmental justice• International treaties
– Basel Convention– Persistent organic pollutants (POPs)
Five Principles for Achieving a Low-Waste Society
1. Everything is connected
2. There is no “away” for wastes
3. Polluters & producers must pay for wastes
4. Different categories of hazardous waste and recyclable waste should not be mixed
5. Reuse, recycle, & compost solid wastes
Three Big Ideas from This Chapter: #1
order of priorities for dealing with solid waste
should be:
Three Big Ideas from This Chapter: #2
Order of priorities for dealing with
hazardous waste should be:
Three Big Ideas from This Chapter: #3
We need to view solid wastes as
wasted resources
and hazardous wastes as
materials that we should not be
producing in the first place.