Waste Management

Solid waste
any unwanted or discarded material we produce that is not a liquid or a gas
municipal solid waste
produce directly from homes an workplaces, containing a mix of paper, food, cans, bottles, etc. –> is referred to as trash or garbage
top 4 contributors to MSW in order by weight
paper, food waste-yard waste, and plastic
Industrial solid waste
produced by mines, agriculture, and industries that supply people with goods and services, such as empty chemical containers, ash, tires, etc.
hazardous (toxic) waste
threatens human health/ environment because it is toxic, chemically active, corrosive, or flammable
organic compounds
solvents, pesticides, dioxins
toxic heavy metals
lead, mercury, cadmium, chroming, and arsenic
how long must highly radioactive waste be stored for
10,000-240,000 years
how much produced MSW can be recycled or reused
90%
what does pollution prevention cause rich countries to do
move polluting industries to poor countries
making products that we use and discard creates…?
large amounts of air, water, and land pollution
what is the second largest component of discarded waste?
food waste
e-waste
toxic and hazardous waste such as PVC, lead, mercury, and cadmium
where is most e-waste shipped
china
ways to deal with solid waste
1. waste management: the attempt to reduce the environmental impact of MSW without trying to reduce the amount of waste produced— most common approach is burying waste, burning it, or shipping it away
2. waste reduction: produce less waste and pollution including reduce, reuse, and recycle
Integrate Waste Management priorities
1. Primary pollution and waste prevention
– change industrial process to eliminate use of harmful chemicals
– use less harmful product
– reduce packaging and materials in products
– makes products that last longer and are easier to repair
2. Secondary pollution and waste prevention
– reuse
– repair
– recycle
– compost
– buy reusable and recyclable products
3. Waste management
– treat waste to reduce toxicity
– incinerate waste
– buy waste in landfills
– release waste into environment for dispersal/dilution
refuse
don’t buy items that we don’t need
reduce
consume less and live a simpler and less stressful life by practicing simplicity
reuse
rely more on items that can be used over and over. reusing products is and important way to reduce resource use, waste, and pollution in developed countries
how can reusing be hazardous in developing countries
because the poor who scavenge in open dumps for items to reuse and sell can be exposed to toxins or infectious diseases
reusing items decreases…reduces…is most effective way to…
-the use of matter and energy resources
– pollution and natural capital degradation
– minimize solid waste
recycling
conservation of resources by converting them into new products and reduces unsightly and environmentally harmful litter
households and workplaces produse 5 major types of materials that can be recycled:
1. paper (easiest to recycle)
2. glass
3. aluminum
4. steel
5. some plastics
materials can be recycled in two ways:
1. primary (closed loops) recycling: materials are turned into new products of the same type
2. secondary recycling: materials converted into different products
two types of wastes that can recycled are…
1. preconsumer: internal waste from manufacturing process
2. postconsumer: external waste from consumer use of products
what percentage of trees are harvested to make paper
55%
glassphalt
a variety of asphalt that uses crushed glass to be and alternative to conventional bituminous asphalt pavement
what is the most recycled material in the U.S
aluminum because of the money gained by recycling
plastics
large polymers/resins (organic compounds) made from oil and natural gas
what do plastics threaten
seabirds, marine mammals, and sea turtles that mistake it for food
reasons why plastic recycling is low
1. it is very difficult to recycle plastic. Many plastic resins are hard to isolate because containers are made of many different resins
2. recovering resins does not yield much material
3. cheaper to make new plastics than to recycle (the exception is PET)
PET
used to makes soft drink bottles, peanut butter jars, etc.
– can be recycles into fiberfill
– most commonly recycled plastic
PVC
used in shampoo and cooking oil bottles
– advantage: replaced lead pipes for a lot of water services reducing lead compounds in water
problems with PET and PVC
if one PET bottle is mixed with the PET, then the recycling is useless
HDPE (high density)
found in milk jude, butter tubs, detergent bottles, and motor oil bottles
– can be recycles into flowerpots, trashcans, traffic barrier cones, and detergent bottles
LDPE (low density)
found in grocery bags, bread bags, shrink wrap, and margarine tub tops.
– can be recycled into new grocery bags
– outlawing plastic grocery bass in some countries is aimed to reduce waste
PP
used in yogurt containers, straws, pancake syrup bottles, and bottle caps
– can recycled into plastic lumber, car battery cases, and manhole steps
7 strategies that industries and communities can use to reduce resource use, waste, and pollution
1. redesign manufacturing processes and products to use less material and energy
2. redesign manufacturing processes to produce less waste and pollution
3. develop products that are easy to repair, reuse, remanufacture, compost, or recycle
4. eliminate or reduce unnecessary packaging
5. use fee-per bag waste collection systems
6. establish cradle-to grave responsibility laws
7. restructure urban transportation systems
98 in the U.S which burned 16% of the nation’s solid waste and produces…
less CO2 emissions than power plants that run on fossil fuels
Incineration advantages
– reduces trash volume
– less need for land fills
– low water pollution
what does covering solid waste reduce the number of?
rats associated with solid waste, lessens the danger of fire, and decreases odor
open dumps
holes in the ground where trash is dumped and are rare in developed countries
sanitary landfills
solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam
what do compacted clay and plastic sheets at the bottom of landfills do?
prevents liquid waste from seeping into groundwater
what is the most serious problem associated with sanitary landfills
lechate
sanitary landfills advantages
– no open burning
– little odor
– can be built quickly
sanitary landfills disadvantages
– noise and traffic
– dust
– release greenhouse gases unless they are collected
how to deal with hazardous wastes
produce less hazardous wastes
– change industrial processes to reduce or eliminate hazardous waste production
– recycle and reuse hazardous waste
convert to less hazardous/non-hazardous 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
what does detoxifying hazardous waste involve
converting them into less hazardous wastes
physical methods
using charcoal or resins to separate out harmful chemicals. deadly wastes can be encapsulated in glass or cement and put in secure storage sites
chemical methods
using chemical reactions that can convert hazardous chemicals to less harmful or harmless chemicals. these reactions can neutralize the waste making it safer
incineration
heating many types of hazardous waste to high temperatures in and incinerator can break them down and convert them to less harmful or harmless chemicals
plasma arc torch
passing electrical current through gas to generate and electric arc and very high temperatures can create plasma
bioremediation
waste management technique that involves the use of organisms to remove or neutralize pollutants from a contaminated site.
– a treatment that uses naturally occurring organisms to break down hazardous substances into less/non-toxic
– ex: phytoremediation, land farming, composting, and rhizofiltration
situ bioremediation
involves treating the contaminated material at the site
ex situ bioremediation
involves the removal of the contaminate material to be treat elsewhere
land-farming
contaminated solid are mixed with soil amendments such as soil bulking agents and nutrients and then they are tilted into the earth. the material is periodically tilled for aeration
phytoremediation
involves using natural or genetically engineered plants to absorb, filter, and remove contaminants from polluted soil and water
deep-well disposal
liquid hazardous wastes are pumped under pressure into dry porous rock far beneath aquifers. 64% of all liquid hazardous wastes in the U.S are disposed of this way
surface impoundments
excavated depressions such as ponds, pits, or lagoons into which liners are placed and liquid hazardous wastes are stored
long-term retrievable storage
metal drums are used to store them in areas that can be inspected and retrieved. this is designed for materials like mercury which cannot be destroyed, detoxified, or safely buried
secure hazardous waste landfills
sometimes hazardous waste are put into drums and burring in carefully designed and monitored sites. This is the best method for long term disposal
mercury is..
a persistant PBT that cannot be destroyed or combusted and doesn’t degrade.
-it bioaccumulates
-released in the environment from natural sources, such as volcanic.geothermal activity, marine environment, or forest fires
-also released from anthropogenic (man-made) sources
Resources Conservation and Recovery Act (RCRA)
principal federal law in the U.S governing the disposal of solid waste and hazardous waste
– protects human health and natural environment from potential hazards or waste disposal)
– energy conservation and natural resources
– reducing the amount of waste generated through source reduction and recycling
– ensuring the management of waste in an environmentally sound manner
Superfund (Comprehensive Environmental Response, Compensation, Liability Act- CERCLA)
U.S federal law designed to clean up sites contaminated with hazardous substances