Pollution: solid waste Flashcards
What is solid waste?
waste in solid form released by human activity onto land
What are some examples of solid waste?
Domestic waste
Specialised solid waste
Radioactive waste
Asbestos and cyanide
What are some examples of domestic waste?
food waste
Single use plastics
Clothes
Electronics
Medicines/ sanitary products
Cleaning detergent
Garden waste
Batteries
what are the 4 main ways to deal with domestic waste?
Landfill
Incineration
Recycling
Composting
What is landfill?
huge hole in the ground
Leachates are collected
Methane may also be collected and burned
May involve land raising
What are the benefits of landfill?
Provides a use for waste/ derelict land
Land can be used after landfill sealed
What are the negatives of landfill?
Air pollution- CO2, CH4
Leachates
Traffic (bin lorries)
Litter/ seagulls
What is happening to total waste sent to landfill?
Declining
What are the benefits of salvaging and recycling besides reducing waste?
saves money and natural resources
What is an example of recycling/ salvaging saving natural resources?
Aluminium
collecting and re-melting/ remoulding metals cut offs
What is a production loop?
recycling process where an industry uses the wastes produced during the manufacturing process its self
What is resources substitution?
the use of a more abundant material instead of less abundant ones e.g., plastic instead of metal
What ore does aluminium come from?
Bauxite
What is aluminium used for?
Cans and aircraft
Why is aluminium used?
It’s light and strong
Where is most aluminium mined?
Jamaica
What are the social, economic and environmental consequences if aluminium mining on Jamaica?
Villages relocated
Top soil removed
Forests/ crops cleared
Bauxite recovered using opencast mines
Bauxite dissolved in sodium hydroxide using high temperature and pressure
Alumina precipitated out
What are the benefits of recycling aluminium?
saves fossil fuels (90-97% energy reduction)
Reduces air pollution (95%)
Reduces water pollution (97%)
Reduces water use
What are the problems with recycling aluminium?
Public motivation
Aluminium often used in alloy- separating metals expensive
Collection and transport costs
Labour costs- collection often labour intensive
Where does incineration of domestic waste mainly done?
Sweden
How many billion tonnes of waste go to landfill each year?
2 billion
How much of Sweden’s garbage goes to lanfill?
1%
How much of Sweden’s garbage is recycled?
47%
How much of Sweden’s garbage is used to generate electricity?
52%
How does trash to electricity work?
trash burned
steam produced
turns turbine
generates electricity
How many tonnes of UK’s waste is exported to Sweden?
2.3 million
What are the advantages of burning domestic waste?
Reduces volume
Can provide electricity and district heating
What are the disadvantages of burning domestic waste?
Air pollution- particulates
Ash toxic and still requires disposal
High capital cost
What is compost?
Produced from waste plant material e.g., grass cutting, fallen leaves and vegetable waste by action of aerobic microorganisms
What does compost consist of?
partly decomposed organic material that is rich in minerals e.g., nitrates
What does rate of compost production depend on?
Temperature
Moisture content
Aeration
What occurs when microorganisms respire in compost?
heat is generated which kills weed seeds and some plant pathogens
Why does compost temperature drop in weeks 9-14?
Reduced food available for microorganisms
More competition so growth rate reduced
Less oxygen becomes available
Change in water/ pH slows growth
What are some examples of specialist solid wastes?
Asbestos
Cyanide
What are specialist wastes?
highly polluting waste products that are very hazardous and must be disposed of seperately
What is asbestos?
term for a group of minerals of microscopic fibres
What was asbestos previously used for?
used in buildings for insultation, flooring and roofing and sprayed on ceilings and walls
Is asbestos still used in the UK?
No it is banned
When does asbestos become a problem?
when the asbestos containing materials are damaged or disturbed so that tiny asbestos fibres can be released into the air and breathed into your lungs
What health problem can asbestos cause?
Cancer called mesothelioma (breathing asbestos dust)
What is the problem with mesothelioma?
fluid builds up in heart, lungs and abdomen
What are heavy metals
naturally occurring elements that have a high atomic weight and a density at least 5 times greater then that of water
Where have heavy metals been applied to human life?
Industry
Domestic
Agricultural
Medical
Technological
What is the source of lead?
lead-acid batteries
roofing
radiation shielding
Metal production and processing
Lead petrol
Old lead piping
Lead paint
What are the impacts of lead?
Toxic to plants and animals
Affects central nervous system
Premature birth increased risk
Reduce birth weight
Learning difficulties
Inhibit growth
Damage kidneys
Joint weakness
Potentially carcinogenic
What are the characteristics of lead that affect its severity?
Solubility increases in acidic water
Dissolves slowly in water
Resistant to corrosion
How can lead be controlled?
Main legislation is National Air Quality Strategy
Restrictions on sale and use
Keep home clean and dust free
Maintain all painted surfaces
What are the sources of mercury?
Waste incineration
Chlorine manufacture
Mercury cells
Metal production
Coal combustion
What are the impacts of mercury pollution?
Toxic to wildlife, plants and microorganisms
Nervous system, lung and kidney damage
Potentially carcinogenic
What characteristics of mercury affects its severity?
Persists indefinitely
Bioaccumulates (liposoluble)
How is mercury pollution controlled?
Clean air act
Restrictions for use in electrical equipment
Phaseout for use in batteries
Sale of products above certain level prohibited
What are the sources of cadmium pollution?
Metal processing (aluminium)
Mine waters
Battery recycling plants
Phosphate fertiliser application
What are the impacts of cadmium pollution on the environment?
Affects photosynthesis and transpiration
growth and reproduction of micro organisms in soil and water
What are the impacts of cadmium pollution on humans?
Carcinogenic when inhaled
Birth defects
Damage to reproductive system
Anaemia
Kidney damage
What characteristics of cadmium affect its severity?
Biomagnifies and bioaccumulates
What are control methods for cadmium pollution?
Bioaccumulator plants for phytoremediation
Legislation banning use for certain activities
What are the sources of tin pollution?
Canned food and drink
What are the impacts of tin pollution?
Toxic to algae, fungi and phytoplankton
Eye/ skin irritation
reduced red blood cells
Brain damage
What are the characteristics of tin pollution that affect its severity?
High persistence (not easily biodegraded)
What are the control methods for tin pollution?
Use of alternatives for cans which are less likely to end up in food or drink
What is cyanide?
A compound that contains a triple bond group known as cyano group which consists or a carbon atom triple bonded to a nitrogen atom
What forms can cyanide be in?
Liquid
Colourless gas
Crystals
What are some examples of gaseous cyanide?
Hydrogen cyanide
Cyanogen chloride
What are some examples of crystallised cyanide?
Sodium cyanide
Potassium cyanide
what is cyanide used for in manufacturing?
Paper
Textiles
Plastics
Chemicals to develop photos
What are cyanide salts used for?
metallurgy for electroplating metal cleaning
Removing gold from ore
What is cyanide gas used for?
extermination of pests and vermin in ships and buildings
How does cyanide affect humans?
Blocks cells ability to produce ATP a source of energy used by your body for natural functions
What happens when a person gets a lethal dose of cyanide?
body’s cells suddenly stop producing ATP
Lung diaphragm and heart are pure muscle so no longer function
Wont be able to breath and cardiac arrest will occur
How long does it take for cyanide to take effect on a person?
2-5 minutes
What are the sources of cyanide?
Smoking
Eating apple seeds or cassava
Burning plastic
Inhaling house fire smoke
How do you dispose of cyanide?
disposed via incineration
What are the by-products of burning cyanide?
Less harmful secondary pollutants CO2 and NOx
Where does most radioactive waste come from?
power plants
What 3 levels of radioactive waste severity are there?
High level waste (HLW)
Intermediate level waste (ILW)
Low level waste (LLW)
What is low level radioactive waste?
Typically from hospitals
Sent straight to land based disposal following packaging
Usually stored in secure containers
What % of total radioactive waste volume is LLW?
90%
What is intermediate level radioactive waste packaging?
Packing involves placing waste in suitable container and immobilising the waste in cement based materials
Geological disposal
What are the typical packages for ILW?
500 litre steel drums or 3m*3 steel boxes
What is geological disposal? (radioactive waste)
placing packaged waste in engineered underground facility
What is the name for the process of high level waste packaging? (radioactive)
Encapsulation and vitrification
How does encapsulation and vitrification take place?
High level waste are concentrated by evaporation then stored in double walled stainless steel tanks inside thick concrete walls awaiting vitrification
What is vitrification?
Waste converted into a borosilicate glass within steel canisters
What are the positives of encapsulation and vitrification?
Long term
Safe storage
What are the negatives of encapsulation and vitrification?
expensive
material remains radioactive for thousands of years
