Management of solid waste Individually, come up with some management strategies for dealing with...
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Management of solid waste Individually, come up with some management strategies for dealing with SDW. HINT. Think about the different stages on your diagram.
Management of solid waste Individually, come up with some management strategies for dealing with SDW. HINT. Think about the different stages on your diagram
Management of solid waste Individually, come up with some
management strategies for dealing with SDW. HINT. Think about the
different stages on your diagram.
Slide 2
Learning outcomes All of you should be able to: Identify and
describe possible management strategies for SDW Most of you should
be able to: Evaluate the different management strategies
Slide 3
Minimising waste Best action that we can take is to produce
less waste in the first place reduce it Reuse it instead of it
becoming waste Recycle it In Germany each household has 4 bins each
for different types of waste. In India and China very little waste
is food waste because it is not thrown away or it is fed to
animals. In MEDCs up to 50% of waste is food waste!
Slide 4
Waste food
Slide 5
Composting Organic waste can be composted or put into anaerobic
digesters. The methane produced can be used as fuel and the waste
used as fertilizer or soil conditioners.
Slide 6
Recycling Separate waste materials and process them for reuse
the economics determine whether it is commercial or not. Some
materials have a high production cost so recycling is particularly
worthwhile e.g. aluminium cans Recycling an aluminium can takes 5%
of the energy needed to extract it from the source, bauxite. It can
be recycled indefinitely with no loss to quality. Recycling one can
saves enough energy to run a TV for three hours.
Slide 7
Recycling in Mexico the Journal of Solid Waste Technology and
Management (2006)
Slide 8
Disposal of waste Landfill Main method of disposal waste is
taken to a suitable site and buried there. Cheapest method
economically speaking. Living near landfill can cause health
problems Carefully selected to be away from areas of high
population density, water courses and aquifers. Lined with plastic
liner to prevent leachate (liquid waste) Leachate is collected in
pipes. Methane is either collected to produce energy or released to
the atmosphere.
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Incinerators Disposal of waste Burn the waste at high
temperatures up to 2000C. Sometimes the waste is pre-sorted.
Reduces waste between 80-90% The heat produced can then be used to
drive a turbine and produce energy or to heat buildings.
Waste-to-energy incineration. In some all waste is burned but this
produces air pollution. (burning plastics / heavy metals produces
dioxins).
Slide 10
Mexico Read the section taken from the article on waste
management in Mexico. 1.What are the main methods used here? 2.What
are the problems with waste management in Mexico? 3.What
improvements are being made? 4.What is going well?
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Material typeExamples Waste produced per capita / kg yr1
Organic material garden waste, food/kitchen waste, wood 188 Paper
newspaper, writing paper, packaging, cardboard, milk cartons 91.2
Plastics soft drink bottles, plastic bags, plastic containers 25.1
Glassjars, bottles, plate glass23.9 Metals steel cans, aluminium
packaging and cans, copper pipes 14.4 Household hazardous paint,
dry cell batteries, car batteries, fluorescent light bulbs 1.9
Miscellaneousceramics (bricks, tiles etc.) rock, ash, soil10.2
Total 354.7 The table below shows the different types of domestic
waste and the amounts produced per capita each year in a city in a
developed country. [Based on Australian Bureau of Statistics data]
1.Calculate the proportion of paper, glass, plastics and organic
material combined as a percentage of total waste.(1) 2.Outline and
evaluate strategies for the management of the domestic waste in the
table above.(3)
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(b)To achieve full marks the answer must include at least one
evaluation comment. most of the waste generated can be recycled or
composted; some of the waste could be reused e.g.
jars/bottles/textiles; composting and recycling would significantly
reduce the amount of domestic waste going to landfill/combustion;
hazardous wastes must be treated appropriately to reduce
environmental damage; the advantages of reducing landfill should be
explained to householders; incentives may be necessary to encourage
householders to recycle rubbish; recycling is cheaper if
householders sort their own waste; recycling will not continue if
there is no demand for recycled goods; manufacturers may be made
responsible for the final disposal of large items e.g.
cars/refrigerators;3 max Any other reasonable point. (a) 100 = 92.5
%; (accept 92.0 to93.0 %) Mark scheme