Скачать презентацию Solid and Hazardous Waste Brian Kaestner Saint Mary s Скачать презентацию Solid and Hazardous Waste Brian Kaestner Saint Mary s

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Solid and Hazardous Waste Brian Kaestner Saint Mary’s Hall Thanks to Miller and Clements Solid and Hazardous Waste Brian Kaestner Saint Mary’s Hall Thanks to Miller and Clements

Wasting Resources Ø Industrial and agricultural waste Ø Municipal solid waste Ø US: 1, Wasting Resources Ø Industrial and agricultural waste Ø Municipal solid waste Ø US: 1, 600 lb/person Dumped in landfills (54%) Sewage sludge 1% Mining and oil and gas production 75% Fig. 21. 2, p. 519 Industry 9. 5% Agriculture 13% Municipal 1. 5% Recycled or composted (30%) Burned in incinerators (16%) Fig. 21. 3, p. 519

Hazardous Wastes Ø Contains one or more of 39 identified compounds Ø Catches fire Hazardous Wastes Ø Contains one or more of 39 identified compounds Ø Catches fire easily Ø Reactive or explosive Ø Corrodes metal containers

Producing Less Waste and Pollution Ø Waste management (high waste approach) Ø Burying, burning, Producing Less Waste and Pollution Ø Waste management (high waste approach) Ø Burying, burning, shipping Ø Waste prevention (low waste approach) Ø Reduce, reuse, recycle Ø Chemical or biological treatment Ø Burial

Dealing with Materials Use and Wastes 1 st Priority 2 nd Priority Primary Pollution Dealing with Materials Use and Wastes 1 st Priority 2 nd Priority Primary Pollution and Waste Prevention Secondary Pollution and Waste Prevention • Change industrial process to eliminate use of harmful chemicals • Purchase different products • Use less of a harmful product • Reduce packaging and materials in products • Reduce products • Repair products • Recycle • Compost • Buy reusable and recyclable products Last Priority Waste Management • Treat waste to reduce toxicity • Incinerate waste • Bury waste in landfill • Release waste into environment for dispersal or dilution • Make products that last longer and are recyclable, reusable or easy to repair Fig. 21. 4, p. 521

Hazardous Waste Regulation in the United States Ø Resource Conservation and Recovery Act Ø Hazardous Waste Regulation in the United States Ø Resource Conservation and Recovery Act Ø Comprehensive Environmental Response, Compensation, and Liability Act Ø Superfund Ø National Priority List Ø Polluter-pays principle Ø Brownfields See Solutions p. 545

Dealing with Hazardous Wastes Produce Less Waste Manipulate processes to eliminate or reduce production Dealing with Hazardous Wastes Produce Less Waste Manipulate processes to eliminate or reduce production Fig. 21. 5, p. 522 Recycle and reuse Convert to Less Hazardous or Nonhazardous Substances Land treatment Incineration Thermal treatment Chemical physical, and biological treatment Ocean and atmospheric assimilation Put in Perpetual Storage Landfill Underground injection Waste piles Surface impoundments Salt formations Arid region unsaturated zone

Detoxifying Wastes Ø Bioremediation Ø Microorganisms break down wastes Ø Phytoremediation Ø Removal of Detoxifying Wastes Ø Bioremediation Ø Microorganisms break down wastes Ø Phytoremediation Ø Removal of wastes from the soil

Above Ground Hazardous Waste Disposal Fig. 21. 17, p. 540 Waste transporter Elevator shaft Above Ground Hazardous Waste Disposal Fig. 21. 17, p. 540 Waste transporter Elevator shaft Hazardous waste Support column Inspector

Deep-well Disposal Advantages Disadvantages Safe method if sites are chosen carefully Leaks or spills Deep-well Disposal Advantages Disadvantages Safe method if sites are chosen carefully Leaks or spills at surface Wastes can be retrieved if problems develop Low cost Leaks from corrosion of well casing Existing fractures or earth quakes can allow wastes to escape into groundwater Encourages waste production Fig. 21. 14, p. 538

Burying Wastes Ø Sanitary landfill Ø Leachate collection Ø Monitoring wells Ø Emit greenhouse Burying Wastes Ø Sanitary landfill Ø Leachate collection Ø Monitoring wells Ø Emit greenhouse gases (CO 2 and methane) Ø Space near where waste is produced

Sanitary Landfill When landfill is full, Electricity layers of soil and clay generator seal Sanitary Landfill When landfill is full, Electricity layers of soil and clay generator seal in trash building Methane storage Topsoil and compressor building Sand Leachate treatment system Clay Garbage Methane gas recovery Pipe collect explosive methane gas used as fuel to generate electricity Compacted solid waste Leachate storage tanks Leachate monitoring well Garbage Sand Synthetic liner Sand Clay Subsoil Groundwater monitoring well Leachate pipes. Leachate pumped up to storage tanks for safe disposal Groundwater Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill Fig. 21. 12, p. 537

Advantages Disadvantages No open burning Noise and traffic Little odor Dust Low groundwater pollution Advantages Disadvantages No open burning Noise and traffic Little odor Dust Low groundwater pollution if sited properly Air pollution from toxic gases and volatile organic compounds release greenhouse gases (methane and CO 2) Can be built quickly Low operating costs Can handle large amounts of waste Filled land can be used for other purposes No shortage of landfill space in many areas Groundwater contamination Slow decomposition of wastes Encourages waste production Eventually leaks and can contaminate groundwater Fig. 21. 13, p. 538

Solutions: Cleaner Production Ø Ecoindustrial revolution Ø Industrial ecology Ø Closed material cycles Ø Solutions: Cleaner Production Ø Ecoindustrial revolution Ø Industrial ecology Ø Closed material cycles Ø Wastes become raw materials Ø Biomimicry Refer to Solutions p. 525

Solutions: Selling Services Instead of Things Ø Service-flow economy Ø Uses a minimum amount Solutions: Selling Services Instead of Things Ø Service-flow economy Ø Uses a minimum amount of material Ø Products last longer Ø Products are easier to maintain, repair, and recycle Ø Customized services needed by customers See Individuals Matter p. 528

Power plant Steam Smokestack Turbine Generator Crane Electricity Wet scrubber Boiler Electrostatic precipitator Furnace Power plant Steam Smokestack Turbine Generator Crane Electricity Wet scrubber Boiler Electrostatic precipitator Furnace Conveyor Water Waste pit Bottom ash Conventional landfill Dirty water Waste treatment Fly ash Hazardous Waste landfill Fig. 21. 10, p. 536

Burning Wastes Ø Mass burn incineration Ø Air pollution Ø Waste to energy Advantages Burning Wastes Ø Mass burn incineration Ø Air pollution Ø Waste to energy Advantages Reduced trash volume Disadvantages High cost Less need for landfills Air pollution (especially toxic dioxins) Low water pollution Produces a highly toxic ash Encourages waste production Fig. 21. 11, p. 536

Reuse Ø Extends resource supplies Ø Maintains high-quality matter Ø Reduces energy use Ø Reuse Ø Extends resource supplies Ø Maintains high-quality matter Ø Reduces energy use Ø Refillable beverage containers Ø Reusable shipping containers and grocery bags See Solutions p. 529

Recycling Aluminum can, used once Ø Primary (closed-loop) Steel can used once Recycled steel Recycling Aluminum can, used once Ø Primary (closed-loop) Steel can used once Recycled steel can Glass drink bottle used once Ø Post consumer waste Recycled aluminum can Recycled glass drink bottle Refillable drink bottle, used 10 times Ø Secondary (open loop) 0 8 16 24 32 Energy (thousands of kilocalories) Fig. 21. 6, p. 529

Characteristics of Recyclable Materials Ø Easily isolated from other waste Ø Available in large Characteristics of Recyclable Materials Ø Easily isolated from other waste Ø Available in large quantities Ø Valuable Ø Pay-as-you-throw garbage collection

Outside users Energy recovery (steam and electricity) Incinerator (paper, plastics, rubber, food, yard waste) Outside users Energy recovery (steam and electricity) Incinerator (paper, plastics, rubber, food, yard waste) Food, grass, leaves Separator Shredder Pipeline Metals Rubber Glass Plastics Paper Recycled to primary manufacturers Residue Compost Landfill and reclaiming disturbed land Fertilizer Consumer (user) Fig. 21. 8, p. 532

Benefits of Recycling Reduces global warming Make fuel supplies last longer Reduces acid deposition Benefits of Recycling Reduces global warming Make fuel supplies last longer Reduces acid deposition Reduces urban air pollution Reduces energy demand Saves energy Reduces solid waste disposal Recycling Reduces mineral demand Reduces water pollution Protects species Reduces habitat destruction Fig. 21. 7, p. 530

Recycling in the US Ø Centralized recycling of mixed waste (MRFs) Ø Separated recycling Recycling in the US Ø Centralized recycling of mixed waste (MRFs) Ø Separated recycling Ø Economic benefits Ø Increasing recycling in the US See Case Study p. 533

Case Studies: Recycling Aluminum, Wastepaper, and Plastics Ø 40% of aluminum recycled in US Case Studies: Recycling Aluminum, Wastepaper, and Plastics Ø 40% of aluminum recycled in US Ø Recycled aluminum uses over 90% fewer resources Ø Paper: preconsumer vs. postconsumer recycling Ø 10% or less of plastic recycled in US Ø Plastics can be very difficult to recycle

Solutions: Achieving a Low-Waste Society Ø Local grassroots action Ø International ban on 12 Solutions: Achieving a Low-Waste Society Ø Local grassroots action Ø International ban on 12 persistent organic pollutants (the dirty dozen) Ø Cleaner production Ø Improved resource productivity Ø Service flow economies