Solid and Hazardous Waste

Transcription

1 LIVING IN THE ENVIRONMENT, 18e G. TYLER MILLER SCOTT E. SPOOLMAN 21 Solid and Hazardous Waste

2 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

3 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

4 Fig. 21-1, p. 576

5 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

6 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

7 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

8 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

9 Fig. 21-5, p. 579

10 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

11 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

12 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 Food/yard waste Hazardous waste Remaining mixed waste To manufacturers for reuse or for recycling Compost Hazardous waste management Landfill Incinerator Fertilizer Fig. 21-6, p. 581

13 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

14 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

15 What We Should Do Reduce Reuse Recycle/Compost What We Do Bury (67%) Recycle/Compost (23.7%) Incinerate (9%) Incinerate Bury Reuse (0.2%) Reduce (<0.1%) Fig. 21-7, p. 581

16 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

17 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

18 Fig , p. 583

19 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

20 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

21 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

22 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

23 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

24 Recycling Has Advantages and Disadvantages Advantages Net economic health Environmental benefits Disadvantages Costly Single-pickup system No separation needed

25 Trade-Offs Recycling Advantages Reduces energy and mineral use and air and water pollution Reduces greenhouse gas emissions Disadvantages Can cost more than burying in areas with ample landfill space Reduces profits for landfill and incinerator owners Reduces solid waste Inconvenient for some Fig , p. 585

26 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

27 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

28 Electricity Smokestack Furnace Boiler Waste pit Ash for treatment, disposal in landfill, or use as landfill cover Fig , p. 588

29 Trade-Offs Waste-to-Energy Incineration Advantages Reduces trash volume Disadvantages Expensive to build Produces energy Produces a hazardous waste Concentrates hazardous substances into ash for burial Emits some CO 2 and other air pollutants Sale of energy reduces cost Encourages waste production Fig , p. 588

30 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

31 Topsoil Sand Clay Garbage Probes to detect methane leaks When landfill is full, layers of soil and clay seal in trash Methane storage and compressor building Methane gas recovery well Compacted solid waste Electricity generator building Pipes collect explosive methane for use as fuel to generate electricity Leachate storage tank Leachate treatment system 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 , p. 589

32 Trade-Offs Sanitary Landfills Advantages 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 Disadvantages Noise, traffic, and dust Releases greenhouse gases (methane and CO 2 ) unless they are collected Output approach that encourages waste production Eventually leaks and can contaminate groundwater Fig , p. 589

33 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

34 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

35 Produce Less Hazardous Waste Change industrial processes to reduce or eliminate hazardous waste production Recycle and reuse hazardous waste Convert to Less Hazardous or Nonhazardous Substances Natural decomposition Incineration Thermal treatment Chemical, physical, and biological treatment Dilution in air or water Put in Perpetual Storage Landfill Underground injection wells Surface impoundments Underground salt formations Stepped Art Fig , p. 591

36 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%

37 We Can Detoxify Hazardous Wastes Collect and then detoxify Physical methods Chemical methods Use nanomagnets Bioremediation Phytoremediation Incineration Using a plasma arc torch

38 Radioactive contaminants Sunflower Organic contaminants Poplar tree Willow tree Inorganic metal contaminants Indian mustard Brake fern Landfill Oil spill Polluted groundwater Soil in Groundwater Decontaminated water out Polluted leachate Soil 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. Phytostabilization Plants such as willow trees and poplars can absorb chemicals and keep them from reaching groundwater or nearby surface water. 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. 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 , p. 593

39 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

40 Trade-Offs Deep-Well Disposal Advantages Safe if sites are chosen carefully Disadvantages Leaks from corrosion of well casing Wastes can often be retrieved Emits CO 2 and other air pollutants Low cost Output approach that encourages waste production Fig , p. 594

41 Trade-Offs Surface Impoundments Advantages Low cost Wastes can often be retrieved Can store wastes indefinitely with secure double liners Disadvantages Water pollution from leaking liners and overflows Air pollution from volatile organic compounds Output approach that encourages waste production Fig , p. 594

42 Fig , p. 595

43 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

44 Case Study: Hazardous Waste Regulation in the United States (cont d.) 1980 Comprehensive Environmental, Compensation, and Liability Act (CERCLA) National Priorities List Superfund sites; 365 cleaned Pace of cleanup has slowed Superfund is broke Laws encouraging the cleanup of brownfields Abandoned industrial sites

45 Fig , p. 596

46 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

47 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

48 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

49 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

50 Reuse, Recycling, and Composting Present Economic Opportunities Freecycle network Upcycling Recycling materials into products of higher value Dual-use packaging

51 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

52 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

53 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

54 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

55 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