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Learn about solid waste generation and disposal methods, types of hazardous waste, e-waste recycling, and the importance of waste prevention and recycling. Discover how composting and incineration play a role in waste management.
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23 Solid and Hazardous Waste
Overview of Chapter 23 • Solid Waste • Waste Prevention • Reducing the Amount of Waste • Reusing Products • Recycling Materials • Hazardous Waste • Types of Hazardous Waste • Management of Hazardous Waste
Waste electronics • Computers replaced every ~18-24 months • Perceived and often obsolete soon • E-waste – electronic waste of high quality plastics and metals that comprise computers (and phones) • U.S. – 30kg per person annually • Business of recycling e-waste • Selling recyclable electronic products • Ship most e-waste overseas (disassembly can increase exposure to hazards)
Solid Waste • U.S. generates more solid waste per capita than any other country • 1.99kg (4.38lb) per person per day • 251 million tons in 2012 (increase from 2010) • Waste generation is highest in developed countries • Instead of repairing items, they are replaced
Types of Solid Waste • Municipal solid waste • Solid material discarded by homes, office buildings, retail stores, schools, etc. • Relatively small portion of solid waste produced • Non-municipal solid waste • Solid waste generated by industry, agriculture, and mining
Disposal of Solid Waste • Three methods • Sanitary Landfills • Replaced open dumps • Incineration • Recycling
Sanitary Landfill • Compacting and burying waste under a shallow layer of soil • Most common method of disposal • Problems • Methane gas production by microorganisms • Contamination of surface water & ground water by leachate • Not a long-term remedy • Few new facilities being opened • Closing a full landfill is very expensive
Sanitary Landfill • Special Problem: Plastic • Much of plastic waste is from packaging • Plastics are chemically stable and do not readily break down and decompose • Photodegradable plastics (break down under sunlight) and biodegradable plastics (broken down by soil microorganisms) have been developed but are slow to be employed
Sanitary Landfill • Special Problem: Tires • Made from materials that cannot be recycled • Can be incinerated or shredded • Tire fires that start are extremely difficult to extinguish, and release toxins to the air!!!
Tire Fire in Texas: 4-9-2017!!! http://inhabitat.com/crazy-texas-tire-fire-demonstrates-why-america-needs-the-epa/ http://www.dec.ny.gov/chemical/8792.html
Incineration • Volume of solid waste reduced by 90% • Produces heat that can make steam to generate electricity • Produce less carbon emissions than fossil fuel power plants • Byproduct • Bottom ash • Fly ash
Incineration - Types of Incinerators • Mass burn (below), Modular, Refuse-derived Mass burn, waste to energy incinerator
Incineration - Problems • Production of hazardous air pollutants • Carbon monoxide, particulates, heavy metals • Reduced by • Lime Scrubbers • Electrostatic Precipitators • Byproduct - Bottom ash (slag) and Fly ash • Must be disposed of in hazardous waste landfills
Composting • Municipal Solid Waste Composting • Includes: Food scraps, Sewage sludge, Agricultural manure, Yard waste • Reduces yard waste in landfills • Can be sold or distributed to community • Concern over heavy metals
Waste Prevention • Three Goals • Reduce the amount of waste • Reuse products • Recycle materials • …..the fourth “R”?????….RESPOND!!! Or “REBUY”….or “REPURPOSE”….or REGULATE!!!!
Reducing Waste • Purchase products with less packaging
Reducing Waste • Source reduction • Products designed and manufactured to decrease the volume of solid waste • Reuse and recycle wastes at the plant where they are generated • 35% weight reduction in aluminum cans since 1970s
Reducing Waste • Pollution Prevention Act (1990) – first U.S. law to focus on reduction of waste at the source • Requires EPA to identify source reduction measures • Requires manufacturers to report their source reduction and recycling activities to the EPA • Dematerialization • Progressive decrease in the size and weight of a product as a result of technological improvements
Reusing Products • Refilling glass beverage bottles used to be standard • Heavier glass required in reusable glass bottles- costs more to make and transport • Cheaper to use lightweight, non-reusable glass • Japan recycles almost all bottles • Reused 20 times • 11 U.S. States have deposits on cans and bottles to promote reuse
Recycling Materials Recycling: In the NE USA, most communities recycle: Glass bottles, newspapers, steel & aluminum cans, plastic bottles, cardboard, office paper
Recycling • U.S. recycles 38% of Municipal Solid Waste • Recycling Paper • U.S. recycles 62.1% • Increased due to consumer demand for recycled paper products
Recycling Materials • Every ton of recycled paper saves: • 17 trees • 7000 gallons of water • 4100 kwatt-hrs of energy • 3 cubic yards of landfill space • Recycle • Glass bottles, newspapers, steel cans, plastic bottles, cardboard, office paper
Recycling Glass • Recycling Glass • US recycles 25% • Costs producers less than new glass • Can be used to make “glasphalt”
Recycling • Recycling Aluminum • Making new can from recycled one costs far less than making a brand new one (economic incentive) • 55% of aluminum was recycled in 2012 • Recycling Metals other than Aluminum • Metal recycling influenced by economy • Lead, gold, iron, steel, silver and zinc • Metallic composition is often unknown • Makes recycling difficult
Recycling • Recycling Plastic • 14% of all plastic is recycled (2012) • May be less expensive to make from raw materials • 31% of PET in water and soda bottles is recycled • Most plastic containers are made of many types of plastic that must be separated to be recycled • (PET = polyethylene terphthalate) • Used to make carpeting, clothing, felt, auto parts, etc.
The Special Problem of Plastics… • Plastic Bags! According to the WorldWatch Institute, “Factories around the world churned out a whopping 4-5 trillion of them in 2002”! • China has instituted a plastic bag ban since 2008! • So has San Francisco, CA and many other cities in the U.S. are now following suit!
Recycling • Recycling Tires • 45% recycled in 2012 • Few products are made from old tires • Playground equipment • Trashcans • Garden hose • Carpet • Roofing materials
Hazardous Waste • Any discarded chemical that threatens human health or the environment • Reactive, corrosive, explosive or toxic chemicals • Dioxins • PCBs • Radioactive waste • 1% of waste stream in U.S. • Love Canal (1977) • Classic case of hazardous waste contaminating human and environmental health Love Canal Toxic Waste Site
Hazardous Waste • Dioxin • Formed as byproduct of combustion of chlorine compounds (medical waste incineration and others) • Bioaccumulates and biomagnifies through food web • Causes cancer, effect reproductive, immune and nervous system • Polychlorinated Biphenyls (PCBs) • Used as cooling fluid, fire retardant, lubricator • Disposed of in open dumps, sewers and fields in 1970s - issue in groundwater today • Continues to biomagnify through food webs (esp. large fish) • Endocrine disrupter
Management of Hazardous Waste • Chemical accidents • National Response Center notified • Typically involves oil, gasoline or other petroleum spill • Current Management Policies • Resource Conservation and Recovery Act (1976, 1984) • EPA identifies which wastes are hazards, and prevents hazardous waste from being disposed on land unless is has been treated properly first to reduce toxicity • Comprehensive Environmental Response, Compensation, and Liability Act (1980) • Commonly known as Superfund
Superfund Program (CERCLA) • Pesticides dumps • Piles of mining wastes • >10,000 hazardous sites qualify • Cleaning up existing hazardous waste: • 400,000 waste sites • Leaking chemical storage tanks and drums (below)
Management of Hazardous Waste • Superfund National Priorities List • 2014: 1,326 sites on the list • States with the greatest number of sites • New Jersey (114) • California (97) • Pennsylvania (95) • New York (86) • Michigan (65)
Management of Hazardous Waste • Biological Treatment of Hazardous Chemicals • Bioremediation - use of bacteria and other microorganisms to break down hazardous waste into relatively harmless products • 1000 species of bacteria and fungi • Time consuming • Inexpensive • Phytoremediation- use of plants to absorb and accumulate hazardous materials in the soil • Phytoextraction • Ex: Indian mustard removes heavy metals
Management of Hazardous Waste • Source reduction • Most effective • Conversion to less hazardous materials • Long-term storage
Basel Convention on the Control of Transboundary Movements of Hazardous Wastes • FROM EPA… • The Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal is a multilateral agreement negotiated under the United Nations Environment Program (UNEP) beginning in 1988. • The negotiators of the Convention wanted to promote environmentally sound management of exported and imported waste, especially in developing countries. • The Basel Convention establishes standards for the transboundary movement of hazardous waste, solid waste, and municipal incinerator ash, including notice to and written confirmation from the receiving country prior to export. • As of December 2015, 183 states and the European Union are parties to the Convention. • The United States is a signatory to the Basel Convention, but has not yet become Party to the Convention.