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Solid and Hazardous Waste. Chapter 16. Core Case Study: Electronic Waste (1). What is electronic waste or e-waste? High-quality material resources Toxic and hazardous waste Disposal methods Cradle-to-grave approach. Core Case Study: Electronic Waste (2).
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Solid and Hazardous Waste Chapter 16
Core Case Study: Electronic Waste (1) • What is electronic waste or e-waste? • High-quality material resources • Toxic and hazardous waste • Disposal methods • Cradle-to-grave approach
Core Case Study: Electronic Waste (2) • Company-sponsored recycling programs • Prevention is best long-term solution
Electronic Waste (E-waste) Fig. 16-1, p. 380
16-1 What Are Solid Waste and Hazardous Waste, and Why Are They Problems? • Concept 16-1 Solid waste represents pollution and unnecessary waste of resources, and hazardous waste contributes to pollution, natural capital degradation, health problems, and premature deaths.
Wasting Resources • Solid Waste • Municipal solid waste • Industrial solid waste • Hazardous or toxic waste • Cause for concern • About 3/4 unnecessary resource waste • Create air and water pollution, land degradation
Scavenging in the Philippines Fig. 16-2, p. 382
Harmful Chemicals in Your Home Fig. 16-3, p. 382
Solid Waste in the United States • Produce 1/3 of world’s solid waste • Mining, agricultural, industrial – 98.5% • Municipal solid waste – 1.5% • High-waste economy • Examples
Solid Wastes Polluting a River in Jakarta, Indonesia Fig. 16-4, p. 383
16-2 What Should We Do about Solid Waste? • Concept 16-2 A sustainable approach to solid waste is first to reduce it, then to reuse or recycle it, and finally to safely dispose of what is left.
Dealing with Solid Waste • Waste management • Waste reduction • Integrated waste management
Raw materials Processing and manufacturing Products Waste generated by households and businesses Solid and hazardous wastes generated during the manufacturing process Remaining mixed waste Hazardous waste Food/yard waste Plastic Glass Metal Paper Hazardous waste management To manufacturers for reuse or for recycling Compost Landfill Incinerator Fertilizer Fig. 16-5, p. 384
Suggested Priorities for Integrated Waste Management Fig. 16-6, p. 384
First Priority Second Priority Last Priority Primary Pollution and Waste Prevention Waste Management Second 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 • Treat waste to reduce toxicity • Incinerate waste • Bury waste in landfills • Release waste into environment for dispersal or dilution • Reuse • Repair • Recycle • Compost • Buy reusable and recyclable products Stepped Art Fig. 16-6, p. 384
Producing Less Waste • Refuse • Reduce • Reuse • Recycle
What Can You Do? Fig. 16-7, p. 385
Reducing Resource Use, Waste, and Pollution • Redesign processes and products • Make products easy to repair, reuse, remanufacture, compost, or recycle • Eliminate or reduce unnecessary packaging • Use fee-per-bag waste collection systems • Establish cradle-to-grave laws
16-3 Why Is Reusing and Recycling Materials So Important? • Concept 16-3 Reusing items decreases the use of matter and energy resources and reduces pollution and 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 • Technology • Refillable containers and cloth bags
Case Study: Refillable Containers • Can reuse glass and polyethylene terephthalate (PET) plastic containers • Throwaway containers from centralized facilities cheaper for corporations • Bottle deposit fee • National bottle bill or ban non-reuseable containers
Recycling • Five major types of materials can be recycled • Primary (closed-loop) recycling • Secondary recycling • Preconsumer (internal) and postconsumer (external) waste • Feasibility and marketing
Mixed Versus Separate Household Recycling • Material recovery facilities (MRF) • Source separation • Pay-as-you-throw (PAUT)
What Can You Do? Fig. 16-8, p. 387
Composting • Decomposing bacteria • Household composting • Organic waste collection facilities • Success large-scale composting • Located centrally • Odor control • Exclude toxic materials
Individuals Matter: Recycling Plastics • 5% plastics recycled • MBA Polymers, Inc – commercial recycling process • Pellets cheaper than virgin plastics • More environmentally friendly
Trade-offs: Recycling Fig. 16-9, p. 388
Encouraging Reuse and Recycling • Fix faulty accounting system • Even the economic playing field • Stabilize prices for recycled materials • Government subsidies • Better-informed public
16-4 Advantages and Disadvantages of Burning or Burying Solid Waste? • Concept 16-4 Technologies for burning and burying solid wastes are well developed, but burning contributes to pollution and greenhouse gas emissions, and buried wastes eventually contribute to pollution and land degradation.
Electricity Smokestack Turbine Steam Crane Electrostatic precipitator Generator Wet scrubber Furnace Boiler Water added Waste pit Dirty water Bottom ash Conveyor Fly ash Ash for treatment, disposal in landfill, or use as landfill cover Fig. 16-10, p. 390
Trade-offs: Incineration Fig. 16-11, p. 390
Burying Solid Wastes • Open dumps • Sanitary landfills • Leachates
When landfill is full, layers of soil and clay seal in trash Topsoil Sand Methane storage and compressor building Clay Electricity generator building Leachate treatment system Garbage Probes to detect methane leaks Methane gas recovery well Pipes collect explosive methane for use as fuel to generate electricity Leachate storage tank Compacted solid waste Groundwater monitoring well Leachate pipes Garbage Leachate pumped up to storage tank for safe disposal Sand Synthetic liner Leachate monitoring well Groundwater Sand Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill Clay Subsoil Fig. 16-12, p. 391
Trade-offs: Sanitary Landfills Fig. 16-13, p. 391
16-5 How Should We Deal with Hazardous Waste? • Concept 16-5 A sustainable approach to hazardous waste is first to produce less of it, then to reuse or recycle it, then to convert it to less hazardous materials, and finally to safely store what is left.
Integrated Hazardous Waste Management Fig. 16-14, p. 392
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 • Recycle and reuse hazardous waste • Natural decomposition • Incineration • Thermal treatment • Chemical, physical, and biological treatment • Dilution in air or water • Landfill • Underground injection wells • Surface impoundments • Underground salt formations Stepped Art Fig. 16-14, p. 392
Detoxifying Hazardous Waste • Bioremediation • Phytoremediation • Incineration
Trade-offs: Phytoremediation Fig. 16-15, p. 393
Storing Hazardous Waste • Deep-well disposal • Surface impoundments • Secure landfills
Trade-offs: Deep Underground Wells Fig. 16-16, p. 393
Trade-offs: Surface Impoundments Fig. 16-17, p. 395
Bulk waste Gas vent Topsoil Plastic cover Earth Impervious clay cap Clay cap Sand impervious clay Water table Earth Leak detection system Groundwater Plastic double liner Reactive wastes in drums Groundwater monitoring well Double leachate collection system Fig. 16-18, p. 396
What Can You Do? Fig. 16-19, p. 397
Science Focus: Mercury (1) • Neurotoxin • Natural sources • Human activities • Coal burning, chemical plants, smelting, electronics
Science Focus: Mercury (2) • Persistent chemical • Exposure and bioaccumulation