Waste Management

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Waste Management

• Chapter 19

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Generation of Waste

• Solid waste is any discarded solid material, such
  as garbage, refuse, or sludges.
• junk mail, coffee grounds, cars.
• Every year, the United States generates more than
  10 billion metric tons of solid waste.

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• The amount of solid waste each American produces
  each year has more than doubled since the 1960s

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Space and Waste

• Many towns are running out of space to dispose of
  waste.
• EXAMPLE New York (Islip Barge)
• In 1987, a barge was loaded with 3,200 tons of
  garbage and left the town of Islip, New York, in
  search of a place to unload its waste.
• The barge sailed for more than five months but no
  one would accept the garbage.

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• The garbage was finally burned in New York, and
  the 430 tons of ash sent to Islip to be buried.

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Waste Disposal

• It is harder to dispose of waste we create
• human population growth less available land
• Average person in the US produces 4.4 lbs of
  solid waste per day.

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Waste Disposal

• Types of Waste
• Biodegradable--can be broken down by biological
  processes.
• Nonbiodegradable--cannot be broken down by
  biological processes.

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Waste Disposal

• Plant and animal matter biodegradable.
• Products made from natural materials are usually
  biodegradable
• newspapers, paper bags, cotton fibers, leather
• Synthetic compounds are not biodegradable.
• polyester, nylon, plastic

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Waste Disposal

• Plastics are made from petroleum or natural gas,
  which consist of carbon and hydrogen.
• Plastics combine these elements in molecular
  chains that are not found in nature.
• Microorganisms have not developed ways to break
  down plastics.
• Plastics may last for hundreds of years.

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Waste Disposal

• Agricultural waste makes up 9 of the total solid
  waste but is biodegradable.
• Fertilizers and pesticides can make agricultural
  waste difficult to dispose of because the waste
  is harmful if returned to the soil.

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Landfills

• A landfill is an area of land where wastes are
  placed for permanent disposal.

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Your Trash in a Landfill

• Number of adults in family____ X 4.5 lbs.
  _____lbs. per day/ adult.Family lbs. per day
  _____X 365 days a year _____family lbs. per
  year.Calculate how much space will be required
  at the landfill for a years worth of your
  familys trash. (Each 1,000 lbs. of material
  requires one cubic yard of space at the
  landfill.)Family lbs. per year _____ divided by
  1,000lbs. _____ cubic yards per year.

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Landfills

• Landfills contain waste and keep it from causing
  environmental problems.
• Waste cannot leach into the soil or groundwater
• Landfills are maintained by covering wastes each
  day

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Landfills

• Leachate--liquid that has passed through solid
  waste and has extracted chemicals from the waste
• Ex. Pesticides, paints, cleansers, battery
  fluids, appliance fluid
• Leachate can flow into groundwater supplies and
  make nearby wells unsafe to drink.

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Landfills

• Methane CH4, highly flammable gas
• Methane forms from anaerobic decomposition.
• Methane gas can be pumped out of landfills and
  burned to generate electricity.
• If not monitored, it may seep through the ground
  and into basements of nearby homes and cause
  explosions.

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Landfills

• The Resource Conservation and Recovery Act
  requires that new landfills be built with
  safeguards.
• Rules
• lined with clay/plastic liner
• systems for collecting and treating leachate
• vents to carry methane out
• Adding safeguards to landfills .
• A new landfill 10 million

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Landfills

• Finding acceptable places to build landfills is
  difficult.
• The total number of active landfills in the US in
  1988 was 8,000
• In 1999, the number decreased to 2,300
• landfills had been filled to capacity.
• Landfills were larger

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Incinerators

• Incinerators can help reduce the amount of solid
  waste in landfills.
• Incinerated materials (ash) take up 90 less
  space in a landfill.
• In 1999, the U.S. had 102 operational
  incinerators that could burn up to 94,000 metric
  tons of solid waste per day.

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Incinerators

• Incinerated materials can be more toxic after
  incineration.
• Air pollution control devices help control the
  amount of toxins released into the air.
• Small amounts of poisonous gases and particles of
  toxic heavy metals are still released into the
  air.

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Source Reduction

• Source reduction is any change in the design,
  manufacture, purchase, or use of materials or
  products to reduce their toxicity before they
  become municipal solid waste.
• Less waste less expense of collecting and
  disposing of waste

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Source Reduction

• You can reduce solid waste by buying products
  with less packaging and not buying disposables
• Ex. buy dish towels not paper towels.
• Manufacturers can reduce waste by redesigning
  products to use less material and to last longer.

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Recycling

• Recycling is the process of recovering valuable
  or useful materials from waste or scrap.
• Recycling also refers to the process of reusing
  some items.
• Making products from recycled materials saves
  energy, water, and other resources.
• Ex. 95 less energy is needed to produce aluminum
  from recycled aluminum than from ore.
• 70 less energy is needed to make paper from
  recycled paper than from trees.

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Recycling

• Increased demand for recycled products
  increased efforts to recycle

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Recycling

• Changing/Recycling the materials we use could
  eliminate much of the solid waste we produce.
• Ex. plastic bottles can be recycled to make
  insulation, carpet yarn, textiles, fiberfill

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Quick Facts

• In 2006, Americans drank about 167 bottles of
  water each, but only recycled an average of 23
  percent. That leaves 38 billion water bottles in
  landfills.
• Bottled water costs between 1 and 4 per gallon
  and 90 percent of the cost is in the bottle, lid
  and label.
• According to the Beverage Marketing Corp, the
  average American consumed 1.6 gallons of bottled
  water in 1976. In 2006 that number jumped to 28.3
  gallons.
• It takes over 1.5 million barrels of oil to
  manufacture a years supply of bottled water.
  Thats enough oil to fuel 100,000 cars.

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Quick Facts

• Eight out of 10 plastic water bottles become
  landfill waste.
• In 2007 we spent 16 billion on bottled water.
  Thats more than we spent on iPods or movie
  tickets.
• Plastic bottles take 700 years before they begin
  to decompose in a landfill.
• If everyone in NYC gave up water bottles for one
  week they would save 24 million bottles from
  being landfilled one month would save 112
  million bottles and one year would save 1.328
  billion bottles from going into the landfill.

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Resin Identification Code

• Printed on the bottom of containers, surrounded
  by a recycling symbol (a triangle of arrows).
• Indicates the type of plastic.
• Numbers 1, 2, and 6 are the most-often recycled
  plastics in the United States.

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Plastic Recycling Process

• Paper labels do not need to be removed from
  plastic bottles or containers
• Lids should be thrown away because they are made
  from a type of plastic that is not recyclable.
• Plastic bottles and containers must be rinsed,
  squashed, and placed in recycle bins for
  collection.

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Plastic Recycling Process

• When compared to other materials, plastic
  polymers require greater processing to be
  recycled.
• Different plastics do not mix well. Heating alone
  is not enough to dissolve such a large molecule
• Plastics must often be of nearly identical
  composition in order to mix efficiently.

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Plastic Recycling Process

• When different types of plastics are melted
  together they tend to act like oil and water, and
  set in layers.
• This causes structural weakness in the resulting
  material, meaning that polymer blends are only
  useful in limited applications.

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Recycling Plastic

• 1. Inspection  Inspect the plastic trash for
  contaminants like rock and glass, and for
  plastics that the plant cannot recycle. 
• 2. Chopping and Washing  The plastic is washed
  and chopped into flakes

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Recycling Plastic

• 3. Flotation Tank  If mixed plastics are being
  recycled, they are sorted in a flotation tank,
  where some types of plastic sink and others
  float.
• Different plastics are sorted in water.
• 4. Drying  The plastic flakes are dried in a
  tumble dryer.

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Recycling Plastic

• 5. Melting  The dried flakes are fed into an
  extruder, where heat and pressure melt the
  plastic.
• Different types of plastics melt at different
  temperatures.

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Recycling Plastic

• 6. Filtering  Plastic is forced through a
  screen to remove any remaining contaminants.
• The molten plastic is then formed into strands.

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Recycling Plastic

• 7. Pelletizing  The strands are cooled in water,
  then chopped into pellets.
• Companies buy the pellets to make new products.

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Types of Plastic

• Number 1 PlasticsPET or PETE (polyethylene
  terephthalate)
• Found in Soft drink, water and beer bottles
  mouthwash bottles peanut butter containers
  salad dressing and vegetable oil containers
• Recycling Picked up through most curbside
  recycling programs.
• Recycled into Polar fleece, fiber, tote bags,
  furniture, carpet, paneling, straps,
  (occasionally) new containers
• PET plastic is the most common for single-use
  bottled beverages, because it is inexpensive,
  lightweight and easy to recycle. It poses low
  risk of leaching breakdown products. Recycling
  rates remain relatively low (around 20), though
  the material is in high demand by
  remanufacturers.

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Types of Plastic

• Number 2 Plastics HDPE (high density
  polyethylene)
• Found in Milk jugs, juice bottles bleach,
  detergent and household cleaner bottles shampoo
  bottles some trash and shopping bags motor oil
  bottles butter and yogurt tubs cereal box
  liners
• Recycling Picked up through most curbside
  recycling programs, although some allow only
  those containers with necks.
• Recycled into Laundry detergent bottles, oil
  bottles, pens, recycling containers, floor tile,
  drainage pipe, lumber, benches, doghouses, picnic
  tables, fencing
• HDPE is a versatile plastic with many uses,
  especially for packaging. It carries low risk of
  leaching and is readily recyclable into many
  goods.

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Types of Plastic

• Number 3 PlasticsV (Vinyl) or PVC
• Found in Window cleaner and detergent bottles,
  shampoo bottles, cooking oil bottles, clear food
  packaging, wire jacketing, medical equipment,
  siding, windows, piping
• Recycling Rarely recycled accepted by some
  plastic lumber makers.
• Recycled into Decks, paneling, mudflaps, roadway
  gutters, flooring, cables, speed bumps, mats
• PVC is tough and weathers well, so it is commonly
  used for piping, siding and similar applications.
  PVC contains chlorine, so its manufacture can
  release highly dangerous dioxins. Also never burn
  PVC, because it releases toxins.

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Types of Plastic

• Number 4 Plastics LDPE (low density
  polyethylene)
• Found in Squeezable bottles bread, frozen food,
  dry cleaning and shopping bags tote bags
  clothing furniture carpet
• Recycling LDPE is not often recycled through
  curbside programs, but some communities will
  accept it. Plastic shopping bags can be returned
  to many stores for recycling.
• Recycled into Trash can liners and cans, compost
  bins, shipping envelopes, paneling, lumber,
  landscaping ties, floor tile
• LDPE is a flexible plastic with many
  applications. Historically it has not been
  accepted through most American curbside recycling
  programs, but more and more communities are
  starting to accept it.

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Types of Plastic

• Number 5 Plastics PP (polypropylene)
• Found in Some yogurt containers, syrup bottles,
  ketchup bottles, caps, straws, medicine bottles
• Recycling Number 5 plastics can be recycled
  through some curbside programs.
• Recycled into Signal lights, battery cables,
  brooms, brushes, auto battery cases, ice
  scrapers, landscape borders, bicycle racks,
  rakes, bins, pallets, trays
• Polypropylene has a high melting point, and so is
  often chosen for containers that must accept hot
  liquid. It is gradually becoming more accepted by
  recyclers.

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Types of Plastic

• Number 6 Plastics PS (polystyrene)
• Found in Disposable plates and cups, meat trays,
  egg cartons, carry-out containers, aspirin
  bottles, compact disc cases
• Recycling Number 6 plastics can be recycled
  through some curbside programs.
• Recycled into Insulation, light switch plates,
  egg cartons, vents, rulers, foam packing,
  carry-out containers
• Polystyrene can be made into rigid or foam
  products -- Styrofoam. Evidence suggests
  polystyrene can leach potential toxins into
  foods. The material is notoriously difficult to
  recycle. Most places still don't accept it,
  though it is gradually gaining traction.

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Types of Plastic

• Number 7 Plastics Miscellaneous
• Found in Three- and five-gallon water bottles,
  'bullet-proof' materials, sunglasses, DVDs, iPod
  and computer cases, signs and displays, certain
  food containers, nylon
• Recycling Number 7 plastics have traditionally
  not been recycled, though some curbside programs
  now take them.
• Recycled into Plastic lumber, custom-made
  products
• A wide variety of plastic resins that don't fit
  into the previous categories are lumped into
  number 7. A few are even made from plants
  (polyactide) and are compostable. Polycarbonate
  is number 7, and is the hard plastic that has
  parents worried these days, after studies have
  shown it can leach potential hormone disruptors
  (BPAs).

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Pro Plastic Info

• It takes 20-40 percent less energy to make
  plastic grocery bags than paper ones.
• Plastics are lightweight and take up so little
  space, it is much more efficient to transport
  them.
• It takes seven trucks to deliver the same number
  of paper bags as can be carried in one truckload
  of plastic bags.

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Plastic Bag Recycling

• Recycling rates for plastic bags are extremely
  low. Only 1 to 3 of plastic bags end up getting
  recycled.
• Economics of recycling plastic bags are not
  appealing. From the process of sorting, to the
  contamination of inks and the overall low quality
  of the plastic used in plastics bags, recyclers
  would rather focus on recycling the more viable
  materials such as soda and milk bottles that can
  be recycled far more efficiently.
• If the economics don't work, recycling efforts
  don't work.

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Plastic Bag Recycling

• EXAMPLE
• it costs 4,000 to process and recycle 1 ton of
  plastic bags, which can then be sold on the
  commodities market for 32
• (Jared Blumenfeld, director of San Francisco's
  Department of the Environment as reported by
  Christian Science Monitor).

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Plastic Bag Recycling

• Many bags collected for recycling never get
  recycled.
• A growing trend is to ship them to Third world
  countries like India and China which are rapidly
  becoming the dumping grounds for the Western
  world's glut of recyclables.
• Rather than being recycled they are cheaply
  incinerated under more lax environmental laws.

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Composting

• Compost is a mixture of decomposing organic
  matter, such as manure and rotting plants, that
  is used as fertilizer and soil conditioner.

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Hazardous Wastes

• Hazardous waste--wastes that are a risk to the
  health of humans or other living organisms.
• They may be solids, liquids, or gases. They often
  contain toxic, corrosive, or explosive materials.

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Hazardous Waste

• The Resource Conservation and Recovery Act (RCRA)
  requires producers of hazardous waste to keep
  records of how wastes are handled.
• The RCRA also requires all hazardous waste
  facilities to be operated according to standards
  designed to prevent pollution.

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The Superfund Act

• In 1980, Congress passed the Comprehensive
  Environmental Response, Compensation, and
  Liability Act, more commonly known as the
  Superfund Act.
• Gave the EPA the right to sue owners of hazardous
  waste sites who illegally dump waste.
• Allowed the EPA to force the owners to pay for
  the cleanup.

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Superfund Act

• Cleaning up improperly discarded waste is
  difficult and extremely expensive.
• The act also created a fund of money to pay for
  cleaning up abandoned hazardous waste sites.
• Cleanup has been completed at only 75 of the
  roughly 1,200 approved or proposed Superfund
  sites.

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Hazardous Waste

• One way to prevent hazardous waste is to find a
  way to reuse it.
• Ex. a company that throws away a cleaning solvent
  after one use can instead sell it to a company
  that produces a product that is not harmed by
  small amounts of contamination in the solvent.

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Hazardous Waste

• Some types of wastes can be treated with
  chemicals to make them less hazardous.
• Ex. cyanides, which are extremely poisonous
  compounds, can be combined with oxygen to form
  carbon dioxide and nitrogen.
• Wastes can also be treated biologically.
• Ex. sludge from petroleum refineries may be
  converted by soil bacteria into less harmful
  substances.

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Hazardous Waste

• Most of the hazardous waste produced in the
  United States is disposed of on land.
• Hazardous wastes in concentrated or solid forms
  are often put in barrels and buried in special
  landfills.
• These landfills have extra safety precautions to
  prevent leakage.

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Hazardous Waste

• Deep-well injection involves pumping hazardous
  wastes into the ground where they are absorbed
  into a dry layer of rock below the level of
  groundwater.
• The waste is covered with cement to prevent
  contamination of groundwater.

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Hazardous Waste

• Surface impoundment - natural depression or a
  human-made excavation that serves as a disposal
  facility that holds an accumulation of wastes.
• i.e. retention pond
• Surface impoundments are ponds with sealed
  bottoms.
• Wastes accumulate and settle to the bottom of the
  pond, while water evaporates from the pond and
  leaves room to add more wastes.

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Retention Ponds

• Allow pollutants to settle out
• Reduce flooding

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Hazardous Waste

• Some hazardous wastes are disposed of by burning
  in specially designed incinerators.
• Incineration can be safe, but it is the most
  expensive form of disposing waste.
• Incinerators need pollution-control devices and
  they need to be monitored for hazardous gases and
  particles.
• Incinerators produce ash that needs to be buried
  in a hazardous waste landfill.

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Hazardous Waste

• Until recently, only local laws regulated waste
  disposal in the United States.
• Until the 1980s, companies would often send
  hazardous waste to landfills in other, less
  populated states.
• Hazardous wastes are now exported through
  international trade agreements to facilities in
  another countries that specialize in treating,
  disposing of, or recycling hazardous waste.

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Hazardous Waste

• Household products can also create hazardous
  waste.

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Hazardous Waste

• It is illegal to pour motor oil on the ground or
  throw it in the trash.
• However, people in the United States throw away
  over 700 million liters (185 million gallons) of
  used motor oil every year. This does not include
  the oil disposed of by service stations and
  automobile repair shops.
• Motor oil can be recycled by taking it to an
  automobile service station.