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WASTE. Gary Johal , Jass Sekhon , Ishaq Ali, Ravdeep , Bunny Ghatrora http://www.youtube.com/watch?v=tnUjTHB1lvM.
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WASTE Gary Johal, JassSekhon, Ishaq Ali, Ravdeep, Bunny Ghatrora http://www.youtube.com/watch?v=tnUjTHB1lvM
An average Canadian generates approximately 1.7kg of solid waste each day. The largest component of this is paper. Not only are Canadians one of the most wasteful people on Earth, we also have one of the worst recycling methods. The wastes contain many of Earth’s resources such as metals, organic nutrients and paper; all things that can be reused or recycled. Canadians dispose of the following solid wastes (non-liquid waste discharged by households and industries): Paper: 36% Organics: 22% Other Material: 16% Plastic: 11% Glass: 9% Ferrous Metals: 6%
If these resources were dealt with properly, the pressure on the world’s limited resources would be decreased, the energy needed to create new resources would be reduced, in turn solving some of the atmospheric problems we are dealing with.
Why so much waste? 1) Population growth 2) The busier families are becoming the more likely they are to replace products instead of reusing them. Things like disposable dishes or paper towels are being manufactured to be used only once. 3) Food packaging; packaging contributes to 30-35% of waste. 4) Industries using low-grade raw materials
Sewage Sewage is the type of waste created most often. It consists of human wastes and water that is used everyday in homes and workplaces. The Chinese realized that human waste is organic and degradable and use it as a fertilizer for their fields; this maintains the nutrient cycle. However, most countries, do not recycle sewage but instead dump the sewage into rivers, lakes and oceans.
Sewage as a Resource Sewage contains many nutrients - Treatment of sewage results in 2 products of disposal, Sewage Effluent which is a liquid and Sludge which is semisolid. - Sewage if is dumped in large quantities into water bodies it can cause and lead to Eutrophication and it may also cause many health problems and diseases. - During the 19th century of the cholera epidemic research on the problems in the Thames River led to discovery that cholera was a disease transmitted by drinking infected water. - In less developed countries river and ground water pollution from untreated sewages is a major health concern and problem.
The Problem of Toxins in Sewage - Time or treatment, human waste reverts into inorganic nutrients without creating great health problems. - In Canada this is true because it has a high standard of public sanitation and a chlorinated water supply. - Until the 70‘s nearly all the detergents contained phosphates and when these phosphates were released into lakes and rivers these phosphates contributed to Eutrophication. - Most detergents now do not contain phosphates instead they are replaced by other cleaning agents which are toxic to some degree. - Alternative to using sewage nutrients for agricultural purposes is to continue to chemical fertilizers in large quantities. - Production of fertilizers requires the heavy use of fossil fuels which contribute to problems such as increased levels of CO2 in the air. - Chemical fertilizers are too expensive for most farmers in developing countries.
Uses of Sewage • Primary Treatment: • Breaking up solids in the sewage through a screening process. Often done in many Canadian cities located on bodies of water. • Secondary Treatment: • degrade the wastes to their inorganic components • Tertiary Treatment: • Recovers the inorganic elements for future use
Eutrophication nutrients, like nitrogen and phosphorous , enrich the water and result in extreme growth of organisms and oxygen depletion. In the 19th century, the Thames River in England was being used as an open sewer. The smell was so bad shields had to be fixed on the windows of houses. Cholera, a disease transmitted by drinking infected water, became a problem. Today, cholera is still linked to drinking water from spills of untreated sewage. In less developed countries, river and groundwater pollution is a health hazard.
Effluent (a form of recycling)The liquid wastes after solids have settled. Advantages Disadvantages increased crop production Reduction in fertilizer costs Reuse of nutrients and water Conservation of surface water sources Potential for disease transmission Potential undesirable effects on soil and groundwater
Solid Waste disposal • http://www.brainpop.com/technology/scienceandindustry/wastemanagement/ • 1) Incineration (Disposal of refuse by burning) • Before combustion, glass and plastics are removed by a screening a process and magnets remove metals. Advantages: • It removes 90% of the bulk that would occupy landfill sites. • Steam and electricity can be generated from the burning Disadvantages • Contributes to CO2 in atmosphere • ash can contain heavy metals or dioxins • disposing of the ash can cause up to $200 per tonne
Solid waste disposal • 2) Landfill (a site used to dispose of solid waste): • Most of our garbage ends up in landfill sites. These dumps are a threat to the environment because gasses like methane escape from the decomposing garbage, toxic wastes can leach into the groundwater, flies and rats can spread diseases. In addition to garbage, diapers entering the landfill add to the smell and provide breeding grounds for bacteria. • Landfills are the preferred method of solid waste disposal because they are cheap. In 1986 the average cost of collecting and disposing garbage was $30/tonne . • http://www.youtube.com/watch?v=hQ_XZNejVdY&fb_source=message
How does a landfill work • Engineered landfill sites are lined at the bottom to prevent seepage and the trenches collect toxic fluids. This decreases the risk of toxic liquids leaching from sites and into ground water causing health hazards. • The sites are compacted from above to seal it. • Many landfill sites are rapidly filling up and cities have transfer their waste to nearby sites. For example, Vancouver trucks some solid waste to a site near Kamloops.
Solution • Reducing the volume of waste that is deposited into our landfill sites is crucial to keep our planet happy. 3 ways we can do this is: • Reduce the amount of garbage we create. The first way to do this is to minimize the amount of disposable materials we use; i.e. products with less packaging, using both sides of a paper, etc.. • Reuse objects more than once or for multipurpose. A plastic container, although has one main purpose, can be reused for storage. Selling or giving away clothes and furniture is another example as well as using cloth bags instead of plastic. • Recycle means to separate materials from garbage that can be reused. Recycling conserves energy, fights pollution and saves jobs.
Products we recycle Paper Cans Milk cartons Plastic containers/bottles Glass bottles
Why is recycling important? Because raw materials are limited, therefore throwing them away not only wastes the material but also the energy used to produce them. An average family could save 407kWh of energy by recycling paper, bottles, glass etc.. a year. Recycling decreases emissions of SOx and NOx Decreases the amount of items we put in landfills Deforestation would be reduced Freshwater demands would be reduced Maintain ecosystems
Blue Box Schemes • People separate different recyclable items from unrecyclable items • Was very successful in some places • Others like metro Toronto wasn’t very successful and 4% of the waste was recycled was put warehouses or disposed of • Businesses were targeted because to how much recyclable products they use. • http://www.youtube.com/watch?v=_GP3JuiX5BY&fb_source=message
Cons Of recycling • Costs: • not always economic • boxes cost $8-10 plus high labour costs • cheaper to send recyclables to landfill • lots of municipalities and waste disposal companies are taking losses • costs of sites are rising market of recycled material is limited by the lack of processing facilities A lot of energy and material is required to organize recycling programs recycling is not a option in some areas plastic is the main problem of recycling, used in everything
Toxic and hazardous materials • Hazardous waste • Labelled hazardous if it is harmful to health or the environment • Are toxic, highly flammable, corrosive, or radioactive, Chemical • Main source is industrial and domestic toxins and waste from laboratories and hospitals • Include acids, metal smelting processes, dioxins from bleaching paper products, pesticides and herbicides • Ontario produces half of the hazardous waste in Canada • Landfills are a danger because toxins can leak into the ground water supply toxin the water additionally can get into rivers lakes and oceans • Best way to solve the problem is to stop making it in the first place
Disposing hazardous waste • Four main methods of getting rid of hazardous waste • Incineration • Oxidizing materials to remove their toxic qualities • Detoxification • By mixing them with other chemicals • Biological degradation • By the action of micro organisms • Waste exchange • To give toxic waste to someone who can make use of it
Transport of hazardous waste • Transportation of dangerous goods Act • Passed in 1980 force in 1985 • All hazardous materials are labelled, recorded, and tracked • All imports and exports of dangerous materials must be approved by the government • Cleaning industrial waste • Since the industrial revolution iron and steel industries have made a big affect on the landscape • The furnaces use to make steel creates air pollution • Large amounts of waste remain from the steel making process
Developing countries and dumping grounds • 1988 African countries were paid to have toxic waste disposed of in their countries • Waste wasn’t properly sealed • Dumped on used pieces of land • No one cared about if the waste will harm to people or damage their resources • They receive $600million for 15 tonnes of waste • July 1988 Nigeria described that dumping waste in Africa is a crime against Africa and its people and Africa didn’t want to do anything with waste anymore
The Sydney Tar ponds cleanup operation • Plans to clean the creek since 1986 • Plan was to remove the hazardous waste • No action were taken until 1995 • The estimate cost to remove the waste was about $120million • The cost to fix the landscape was $20.4million • Project began in 1996
CASE STUDY 1/3 of timber is cut for paper makingtimber is harvested then it can grow in some places • recycling saves timber,25% of paper is now recycled • saves energy and forests • demand for good paper is high, photocopying paperiron-steel • steel one of the most important and used material everywhere • don't have to recycle steel, abundant everywhere • 4% of the world is just scrap metal • takes a lot of energy to recycle steelmini mills increase steel recycling • a lot of steel would be recycled is the market for recycled steel were free of restrictions • countries keep steel prices high, to restrict exports Aluminium • out of all the things recycled the most is gained from aluminum • takes more energy to make another material • recycling this reduces environmental problem created by bacoxite mining Composting • our food, wastes garbage consists of degradable organic wastes • high water and organic content make these raw material valuable for gardens