1 / 41

CHAPTER 21

CHAPTER 21. SOLID & HAZARDOUS WASTE. Food Waste is the World's Dumbest Problem. Types of solid waste. Organic - Kitchen wastes, vegetables, flowers, or fruits. Something that will decay. Radioactive - Spent fuel rods and smoke detectors. Can take hundreds of thousands of years to decompose.

karmaj
Télécharger la présentation

CHAPTER 21

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. CHAPTER 21 SOLID & HAZARDOUS WASTE

  2. Food Waste is the World's Dumbest Problem

  3. Types of solid waste • Organic- Kitchen wastes, vegetables, flowers, or fruits. Something that will decay. • Radioactive- Spent fuel rods and smoke detectors. Can take hundreds of thousands of years to decompose. • Recyclable- Paper, glass, metals, and some plastics. • Soiled- Hospital wastes, cotton, and cloth which can take 2-5 months to decompose. • Toxic- Paints, chemicals, pesticides, and so on. Can take hundreds of years to decompose.

  4. Planned Obsolescence? • Until a society becomes wealthy they generate little waste • Every object that no longer has value for its original purpose is re-purposed • Prior to1900: Almost everything recycled • After WWII: • Able to purchase things that could be used and thrown away • Shift toward designing a product in such a way that it would need to be replaced in a much shorter time • U.S. Is the leader of “Throw Away Societies”

  5. MUNICIPAL SOLID WASTE (MSW) • Refuse collected by municipalities from households, small businesses, and institutions such as schools, prisons, municipal buildings and hospitals.

  6. Waste Stream • Depending on what and how the materials, products, or goods are used, they can remain in the consumer use system for a long time • Ultimately all products wear out, lose their value, or are discarded • They enter the waste stream- the flow of solid waste that is recycled, incinerated, placed in a solid waste landfill, or disposed of in another way

  7. COMPOSITION OF MUNICIPAL SOLID WASTE

  8. Types of Disposal • R3: Reduce, Reuse, Recycle • Composting • Land Disposal - Sanitary Landfill • Land Disposal - Open Dumping • Burning, Incineration, or Energy Recovery • Exporting • Remanufacturing

  9. Reduce, Reuse, Recycle In the 1990s people in the US began promoting the idea of diverting materials from the waste stream with a popular phrase #1 Reduce- less waste (or none) #2 Reuse- reusing single-use items #3 Recycle- materials are collected and converted into raw materials and then used to produce new objects (Divided into TWO categories…)

  10. Closed- loop recycling:a discarded carpet can be recycled into a new carpet, new raw materials and additional energy are needed. Open – Loop Recycling:a beverage container is used once and then recycled into something else like a fleece jacket.

  11. Recycling Pros: • Turns waste into an inexpensive resource. • Reduces impact on landfills. • Reduces energy requirements to produce product. • Reduces dependence on foreign oil. • Reduces air and water pollution. • Beverage container deposit laws provide economic incentive to recycle. Cons: • Poor regulation. • Fluctuations in market prices. • Throwaway packaging is more convenient. • Current policies and regulations favor extraction of raw materials. Energy, water, and raw materials are sold below real costs to stimulate jobs and the economy.

  12. Total weight of MSW recycled and % MSW recycled in US over time. • Today we recycle roughly 1/3 MSW, but places like Japan have recycling rates closer to 50%

  13. Reuse Pros: • Most efficient method of reclaiming materials. • Industry models already in place - auto salvage yards, building materials, etc. • Refillable bottles can be used. Cons: • Costs of collecting dropped-off materials on a large scale is expensive. • Costs of washing and decontaminating containers is expensive. • Only when items are expensive and labor is cheap is reuse economical.

  14. E-Waste • E-waste can contain heavy metals like Lead, Mercury and Cadmium. • Much e-waste is exported to China where workers separate valuable metals from other materials using fire and acids often w/out personal protective equipment (PPE) • Electronic waste from televisions, computers, cell phones comprise ~2% of the waste stream

  15. Composting • Organics that have decomposed under controlled conditions to produce a nutrient-rich material.

  16. Composting Pros: • Creates nutrient-rich soil additive. • Aids in water retention. • Slows down soil erosion. • No major toxic issues. Cons: • Neighbors and HOA reactions to odor, vermin, and insects. • NIMBY (Not In My Backyard) thinking

  17. Municipal Composting Facility: typical facility collects almost 100,000 metric tons of food scraps and paper per year and turns it into usable compost

  18. Landfills • Municipality or private enterprise constructs a landfill at a substantial cost • Costs are recovered by charging a “tipping fee” because each truckload is put on a scale after the MSW is weighed it is tipped into the landfill • Tipping fees at solid waste landfills average around $35 per ton in the US • Create an economic incentive to reduce the amount of waste that goes to the landfill

  19. Sanitary Landfills • Most solid waste is buried in landfills or incinerated • Sanitary landfills- engineered ground facilities designed to hold MSW with as little contamination of the surrounding environment as possible. • Leachate-the water that leaches through the solid waste and removes various chemical compounds with which it comes into contact. The fate of MSW in US.

  20. A Modern Sanitary Landfill: Features include: Clay liner, leachate collection system, the cap, methane extraction system.

  21. Sanitary Landfill Pros: • Waste is covered each day with dirt to prevent insects and rodents. • Plastic liners, drainage systems, and other methods help control leaching material into groundwater. • Collection of methane and use of fuel cells to supplement energy demand. • Use of anaerobic methane generators reduces dependence on other energy sources. Cons: • Rising land prices. Current costs are $1 million per 2.5 acres. • Transportation costs to the landfill. • High cost of running and monitoring. • Legal liability. • Suitable areas are limited • Degradable plastics do not decompose completely.

  22. Problems with Landfills • No matter how careful the design and engineering, there is always the possibility that leachate from a landfill will contaminate underlying and adjacent waterways • EPA estimates that virtually all landfills in the US have had some leaching • Methane gas (a very persistent greenhouse gas) can also be released during decomposition of the garbage

  23. Open Dumping Pros: • Inexpensive • Provides a source of income to the poor by providing recyclables to sell. Cons: • Trash can blow away in the wind. • Vermin and disease. • Leaching of toxic materials into the soil. • It’s not very aesthetic.

  24. Incineration • The process of burning waste materials to reduce its volume and mass and sometimes to generate electricity and heat.

  25. Burning, Incineration, or Energy Recovery Pros: • Heat can be used to supplement energy requirements. • Reduces impact on landfills. • Mass burning is inexpensive. • What is left is 10-20% of original volume. • United States incinerates 15% of its wastes. • France, Japan, Sweden, and Switzerland incinerate >40% of their wastes and use the heat to generate electricity. Cons: • Air pollution including lead, mercury, NOx, cadmium, SO2 , HCl, and dioxins. • Sorting out batteries, plastics is expensive. • No way of knowing toxic materials. • Ash is more concentrated with toxic materials. • Initial costs of incinerators are high. • Adds to acid deposition.

  26. Problems with Incineration • Generally tipping fees are much higher at incinerators than landfills, average around $70 per ton • May release air pollutants such as organic compounds from the incomplete combustion of plastics and metals • Require large quantities of MSW on a daily basis in order to burn efficiently and to be profitable

  27. Exporting (or shipping our s**t somewhere else!) Pros: • Gets rid of problem immediately. • Source of income for poor countries. Cons: • Garbage imperialism or environmental racism. • Long-term effects are not known. • Expensive to transport.

  28. Remanufacturing(making old s**t new again!) Pros: • Recovers materials that would have been discarded. • Beneficial to inner cities as an industry because material is available and jobs are needed. Cons: • Toxic materials may be present (CFCs, heavy metals, toxic chemicals, etc.) • Stigma of “remanufactured” instead of “new”

  29. Hazardous Waste • Liquid, solid, gaseous, or sludge waste material that is harmful to humans or ecosystems. • Can be generated by small businesses such as dry cleaners, automobile service stations, small farms, and individual households • Oven cleaners, batteries, and lawn fertilizers

  30. Hazardous Waste • Most municipalities do not have regular collection sites • Ask homeowners to store them in a safe location until periodic collections are held • Every aspect is more expensive and more difficult than the disposition of ordinary MSW • Collection sites for hazardous waste must be staffed with specially trained personnel. • Hazardous waste must be treated before disposal.

  31. Hazardous Waste • Hazardous waste must be treated before disposal • EPA defines this as making it less environmentally harmful • The waste must usually be altered through a series of chemical procedures

  32. Laws • Regulation and oversight of the handling of hazardous waste falls under two pieces of federal legislation: 1) Resource Conservation and Recovery Act (RCRA)- designed to reduce or eliminate hazardous waste. Also know as “cradle-to-grave” tracking. RCRA ensures that hazardous waste is tracked and properly disposed of.

  33. Laws • 2) Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)- also know as “Superfund”. • Puts a tax on the chemical and petroleum industries. This revenue is used to cleanup abandoned and non-operating hazardous waste sites where a responsible party cannot be found. • Requires the federal government to respond directly to the release of substance that may pose a threat to human health or the environment

  34. CERCLA - Superfund Act (1980) • Provides authority for the federal government to respond to releases or possible releases of hazardous substances that could threaten public health and/or the environment. • Established rules for closed and abandoned hazardous waste sites. • Established liability for corporations responsible for hazardous waste sites. • Created a trust fund for clean up if responsible parties for contaminated sites could not be found.

  35. CERCLA - Superfund Act (1980) • The EPA and state agencies use the Hazard Ranking System (HRS) to calculate a site score (ranging from 0 to 100) based on the actual or potential release of hazardous substances from a site. • A score of 28.5 places a site on the National Priorities List, eligible for long-term remedial action (i.e., cleanup) under the Superfund program. • As of 9 August 2016, there were 1,328 sites listed; an additional 391 had been delisted, and 55 new sites have been proposed.

  36. National Priorities List (Superfund) Sites The EPA’s list of National Priority List (NPL) of contaminated sites that are eligible for clean up funds

  37. Love Canal, New YorkHazardous waste chemical pollution in US, 1970’s An elementary school & housing development were constructed on top of large quantities of hazardous chemical waste site. Chemicals such as: Benzene, trichloroethylene, were found in the basements of homes resulted in a large # of illnesses. The site was listed as a superfund site, and inhabitants of the area were evacuated. Taken off the list in 1994 because the physical clean up had been completed & site no longer deemed threat to human health.

  38. International Consequences • Because of difficulties of disposing hazardous waste, municipalities and industries sometimes try to send the waste to countries with less stringent regulations • Illustrated by many reports of garbage and ash barges that travel the oceans looking for a developing country willing to accept hazardous waste from the US in exchange for cash

  39. Life-Cycle Analysis • Important systems tool that looks at the materials used and released throughout the lifetime of a product– from the procurement of raw materials through their manufacture, use, and disposal • Also called the cradle-to-grave analysis • In theory it should help a community determine whether incineration is more or less desirable than using a landfill • BUT there are problems in determining the overall environmental impact of specific materials

  40. Integrated Waste Management • A method that seeks to develop as many options as possible, to reduce environmental harm and cost. • Reduction, recycling, composting, landfills, and incineration are some ways IWM is utilized.

  41. A recyclable carpet & collection site facility for e-waste & recycling in Chile. **Looking at holistic waste management -EX) Certain carpet manufacturers design their carpets so that when worn out they can be easily recycled into new carpeting

More Related