Presentation is loading. Please wait.

Presentation is loading. Please wait.

Solid and Hazardous Waste

Similar presentations

Presentation on theme: "Solid and Hazardous Waste"— Presentation transcript:

1 Solid and Hazardous Waste
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 Figure 21-1: These workers in Taizhou City in China’s Zhejiang Province are recovering valuable materials from scrap computers shipped from the United States. Question: Have you disposed of an electronic device lately? If so, how did you dispose of it? 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 In the natural world, there is essential no waste because the waste of one organism become nutrients or raw materials for others. Because of humans we have…

7 We Throw Away Huge Amounts of Useful Things
Solid waste Any unwanted or discarded material we produce that is not liquid or gas 1. Industrial solid waste Produced by mines, farms, industries 2. Municipal solid waste (MSW) Garbage or trash produced by homes and workplaces

8 In more developed countries:
Most waste ends up in: Rivers, lakes, the ocean, and natural landscapes In more developed countries: MSW is buried in landfills or burned in incinerators In less developed countries: -open dumps, people use or sell

9 Hazardous Waste Is a Serious and Growing Problem
Hazardous waste (toxic waste) Any discarded material or substance that threatens human health of the environment Examples: industrial solvents, hospital medical waste, car batteries, dry-cell batteries, and household pesticide products

10 Classes of hazardous waste
Organic compounds Various solvents, pesticides, PCBs, and dioxins Toxic heavy metals Lead, mercury, arsenic Radioactive waste Waste produced by nuclear power plants and nuclear weapon facilities Must be stored for 10,000 to 240,000 years; have not found safe way to isolate

11 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 1.5% is MSW (Each American throws away 7 pounds of trash every day or 2,750 pounds a year) Most wastes break down very slowly If at all

12 Figure 21-5: A year’s worth of solid waste produced by family of four in San Diego, California. Recyclable items are on the left and the rest of their MSW is on the right. Fig. 21-5, p. 579

13 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

14 We Can Burn, Bury, or Recycle Solid Waste or Produce Less of It
1.Waste management Reduce harm, but not amounts Typically involves mixing wastes together and then transferring them from one part of the environment to another, usually by burying them, burning them, or shipping them to another location

15 3.Integrated waste management
2.Waste reduction Use less and focus on reuse, recycle, compost 3.Integrated waste management Uses a variety of strategies

16 To manufacturers for reuse or for recycling Compost Landfill
Raw materials Processing and manufacturing Products Solid and hazardous wastes generated during the manufacturing process Waste generated by households and businesses Figure 21-6: We can reduce wastes by refusing or reducing resource use and by reusing, recycling, and composting what we discard, or we can manage them by burying them in landfills or incinerating them. Most countries rely primarily on burial and incineration. Question: What happens to the solid waste you produce? Food/yard waste Hazardous waste Remaining mixed waste Plastic Glass Metal Paper To manufacturers for reuse or for recycling Hazardous waste management Compost Landfill Incinerator Fertilizer Fig. 21-6, p. 581

17 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- convert it to useful items and buy products made from recycled materials.

18 Composting Form of recycling that uses bacteria to decompose yard trimmings, vegetable food scraps, & biodegradable waste into materials that can increase soil fertility.

19 Refusing, Reducing, Reusing, and Recycling (cont’d.)
Six strategies to reduce resource us, waste, and pollution: 1. Change industrial processes to eliminate harmful chemicals 2. Redesign manufacturing process to use less material and energy 3. Develop products that are easy to recycle 4. Eliminate unnecessary packaging 5. Use fee-per-bag waste collection systems 6. Establish cradle-to grave responsibility

20 What We Should Do What We Do Reduce Bury (67%) Reuse
Recycle/Compost (23.7%) Recycle/Compost Incinerate (9%) Incinerate Reuse (0.2%) Figure 21-7: Priorities recommended by the U.S. National Academy of Sciences for dealing with municipal solid waste (left) compared with actual waste-handling practices in the United States based on data (right). Question: Why do you think most countries do not follow most of the scientific-based priorities listed on the left? Bury Reduce (<0.1%) Fig. 21-7, p. 581

21 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

22 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

23 Figure 21-11: Individuals matter
Figure 21-11: Individuals matter. There are many ways to reuse the items we purchase. Question: Which of these suggestions have you tried and how did they work for you? Fig , p. 583

24 There Is Great Potential for Recycling
Primary, closed-loop recycling Materials recycled into new products of the 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

25 Steps to recycling: 1. collecting materials
2. converting materials to new products 3. selling and buying of products

26 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

27 We Can Mix or Separate Household Solid Wastes for Recycling
Materials-recovery facilities (MRFs) Machines or workers separate mixed waste to recover valuable materials for sale to manufacturers as raw materials. Source separation Pay-as-you-throw Fee-per-bag

28 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

29 Recycling Plastics Plastics Currently only 7% is recycled in the U.S.
Composed of resins created from oil and natural gas Currently only 7% is recycled in the U.S. Many types of plastic resins making it difficult to separate from products that contain them

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

31 Trade-Offs Recycling Advantages Disadvantages
Reduces energy and mineral use and air and water pollution Can cost more than burying in areas with ample landfill space Reduces greenhouse gas emissions Reduces profits for landfill and incinerator owners Figure 21-14: Recycling solid waste has advantages and disadvantages (Concept 21-3). Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Reduces solid waste Inconvenient for some Fig , p. 585

32 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

33 Burning Solid Waste Has Advantages and Disadvantages
Waste-to-energy incinerators Use the heat they generate to boil water and make steam for heating water or for producing electricity US incinerates about 9% of MSW

34 Electrostatic precipitator
Electricity Smokestack Steam Turbine Crane Generator Furnace Wet scrubber Boiler Electrostatic precipitator Waste pit Water added Figure 21.13: Solutions. A waste-to-energy incinerator with pollution controls burns mixed solid wastes and recovers some of the energy to produce steam to use for heating or producing electricity. Questions: Would you invest in such a project? Why or why not? Bottom ash Dirty water Conveyor Fly ash To waste treatment plant Ash for treatment, disposal in landfill, or use as landfill cover Fig , p. 588

35 Waste-to-Energy Incineration
Trade-Offs Waste-to-Energy Incineration Advantages Disadvantages Reduces trash volume Expensive to build Produces a hazardous waste Produces energy Concentrates hazardous substances into ash for burial Figure 21-16: Incinerating solid waste has advantages and disadvantages (Concept 21-4). These trade-offs also apply to the incineration of hazardous waste. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Emits some CO2 and other air pollutants Sale of energy reduces cost Encourages waste production Fig , p. 588

36 Burying Solid Waste Has Advantages and Disadvantages
1.Sanitary landfills About 67% of MSW in US; Consist of compacted layers of waste between clay or foam Have strong bottom liners and containment systems to prevent leakage

37 2.Open dumps Widely used in less-developed countries Large pit
Rare in developed countries Large pit Sometimes garbage is burned

38 When landfill is full, layers of soil and clay seal in trash Topsoil
Sand Electricity generator building Methane storage and compressor building Clay Garbage Leachate treatment system Probes to detect methane leaks Pipes collect explosive methane for use as fuel to generate electricity Methane gas recovery well Leachate storage tank Compacted solid waste Figure 21-17: Solutions. A state-of-the-art sanitary landfill is designed to eliminate or minimize environmental problems that plague older landfills. Question: Some experts say that these landfills will eventually develop leaks and could emit toxic liquids. How do you think this could happen? Garbage Groundwater monitoring well Leachate pipes 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 , p. 589

39 Trade-Offs Sanitary Landfills Advantages Disadvantages
Low operating costs Noise, traffic, and dust Releases greenhouse gases (methane and CO2) unless they are collected Can handle large amounts of waste Filled land can be used for other purposes Output approach that encourages waste production Figure 21-18: Using sanitary landfills to dispose of solid waste has advantages and disadvantages (Concept 21-4). Questions: Which single advantage and which single disadvantage do you think are the most important? Why? No shortage of landfill space in many areas Eventually leaks and can contaminate groundwater Fig , p. 589

40 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

41 We Can Use Integrated Management of Hazardous Waste
Integrated management of hazardous wastes: 1.Produce less 2.Convert to less hazardous substances 3.Rest in long-term safe storage Increased use for postconsumer hazardous waste

42 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 Figure 21-20: Integrated hazardous waste management: The U.S. National Academy of Sciences has suggested these priorities for dealing with hazardous waste (Concept 21-5). Question: Why do you think most countries do not follow these priorities? Stepped Art Fig , p. 591

43 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%

44 We Can Detoxify Hazardous Wastes
Collect and then detoxify 1.Physical methods 2.Chemical methods 3.Use nanomagnets 4.Bioremediation 5.Phytoremediation Incineration Using a plasma arc torch

45 Radioactive contaminants
Organic contaminants Inorganic metal contaminants Poplar tree Indian mustard Brake fern Sunflower Willow tree Landfill Oil spill Figure 21-22: Solutions. Phytoremediation involves using various types of plants that function as pollution sponges to clean up contaminants such as radioactive substances (left), organic compounds (center), and toxic metals (right) from soil and water. Polluted groundwater in Decontaminated water out Polluted leachate Soil Soil Groundwater 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

46 We Can Store Some Forms of Hazardous Waste
Burial on land or long-term storage Last resort only; “out of site, out of mind” Deep-well disposal Liquid hazardous wastes are pumped under pressure through a pipe into dry, porous rock formations 64% of hazardous liquid wastes in the U.S. Surface impoundments Lined ponds, pits, or lagoons in which liquid hazardous wastes are stored

47 Secure hazardous waste landfills
Expensive; both liquid and solid hazardous wastes are put into drums or other containers and buried

48 Trade-Offs Deep-Well Disposal Advantages Disadvantages
Safe if sites are chosen carefully Leaks from corrosion of well casing Emits CO2 and other air pollutants Wastes can often be retrieved Figure 21-24: Injecting liquid hazardous wastes into deep underground wells has advantages and disadvantages. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Output approach that encourages waste production Low cost Fig , p. 594

49 Trade-Offs Surface Impoundments Advantages Disadvantages
Low cost Water pollution from leaking liners and overflows Wastes can often be retrieved Air pollution from volatile organic compounds Figure 21-26: Storing liquid hazardous wastes in surface impoundments has advantages and disadvantages. Questions: Which single advantage and which single disadvantage do you think are the most important? Why? Can store wastes indefinitely with secure double liners Output approach that encourages waste production Fig , p. 594

50 Figure 21-28: Individuals matter
Figure 21-28: Individuals matter. You can reduce your output of hazardous wastes (Concept 21-5). Questions: Which two of these measures do you think are the most important ones to take? Why? Fig , p. 595

51 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

52 Case Study: Hazardous Waste Regulation in the United States (cont’d.)
1980 – Comprehensive Environmental, Compensation, and Liability Act (CERCLA) National Priorities List 2013 – 1320 Superfund sites; 365 cleaned Pace of cleanup has slowed Superfund is broke Laws encouraging the cleanup of brownfields Abandoned industrial sites

53 Figure 21-29: Leaking barrels of toxic waste found at a Superfund site that has since been cleaned up. Fig , p. 596

54 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

55 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 Apply precautionary principle

56 Providing Environmental Justice for Everyone Is an Important Goal
Everyone is entitled to protection from environmental hazards Communities in the U.S. have the largest share of hazardous waste dumps: African American, Asian American, Latinos, and Native American Environmental discrimination has led to environmental justice movement

57 We Can Encourage Reuse and Recycling
Factors that hinder reuse and recycling: 1.Market prices do not include harmful costs 2.Economic playing field is uneven 3.Demand for recycled products fluctuates Governments can pass laws requiring companies to reuse and recycle

58 Reuse, Recycling, and Composting Present Economic Opportunities
1. Freecycle network 2. Upcycling Recycling materials into products of higher value 3. Dual-use packaging

59 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

60 International Treaties Have Reduced Hazardous Waste (cont’d.)
2000 – delegates from 122 countries completed a global treaty Control 12 persistent organic pollutants (POPs) Include DDT, PCBs, dioxins Discovered that 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

61 We Can Make the Transition to Low-Waste Societies
Norway, Austria, and the Netherlands Committed to reduce resource waste by 75% Key principles 1.Everything is connected 2.There is no away 3. Producers and polluters should pay for their wastes 4. We can mimic nature by reusing, recycling, composting, or exchanging MSW we produce

62 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

63 Three Big Ideas The order of priorities for dealing with solid waste should be to: Produce less of it Reuse and recycle as much of it as possible Safely burn or bury what is left

64 Three Big Ideas (cont’d.)
The order of priorities for dealing with hazardous waste should be to: Produce less of it Reuse or recycle it Convert it to less hazardous material Safely store what is left

65 Three Big Ideas (cont’d.)
View solid wastes as wasted resources, and hazardous wastes as materials that we should not be producing in the first place

66 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

Download ppt "Solid and Hazardous Waste"

Similar presentations

Ads by Google