Waste Management Flashcards
What does the waste pyramid look light right now?
What do we want it to look like?
Right now:
Prevention- top (last resort)
Minimize
Reuse
Recycling
Energy Recovering
Disposal - bottom (first resort)
We want to invert this pyramid!
- prevention/ reduction should be the top priority, disposal should be a last resort
T/F
wealthy countries have the highest total waste
false
- wealthy countries make the most waste per capita, but developing countries have more waste in total b/c rich countries export their waste there
The most effective way to reduce waste is:
minimize the amount of material that goes into products
Municipal waste=
waste produced by consumers, public facilities, and small businesses
municipal wastewater=
water that has been used by people in some way
inc:
- sewage
- water from showers sinks, washing machines, etc
____ are the most common disposal system
landfills
What are the 2 types of landfill systems?
- Bottom Liner System:
- layers of impermeable materials seal off waste from contact with soils/ water - Cap System
- pipes at the bottom collect residues and methane which is used for energy
methane gas from landfills is a ___ energy source, but not ___
green (naturally occuring)
not clean (has emissions)
What’s the Freshkills Park Project?
New York City
- landfill was here, and closed in 2001 because it reached its limit
- city built a park over it, now has many uses
landfills are another example of the ____ movement
what’s their solution?
Not in my backyard (NIMBY)
they export their waste to less wealthy areas
The ___ ____ of _____ (date) was a treaty on control of transboundary movements of hazardous wastes and their disposal
Basel Convection of 1992
wanted to stop movement of waste around the world, esp to poorer countries without regulations
What’s e-waste?
Why is it so hard to deal with?
electronic waste (phones, fridges, etc)
contains metals
- can be toxic
Give 2 examples of unregulated or illegal sites where e-waste is sent to
- Guiyu, China
- recognized disposal site, but not regulated - Accra, Ghana
- illegal site where they burn electronics
lots of mercury and lead poisoning in these areas
How do incinerators work to dispose of waste?
- combust it at very high temps
- reduces its volume by up to 90%
- metals (which can be recycled) are removed before incineration
what’s the biggest problem with incinerators?
produce a lot of air pollution and secondary pollutants
T/F
some incinerators in waste-to-energy facilities use the heat from waste incinerators to produce electricity
true
The Edmonton Waste Management Center (one of the best in the world) manages 4 waste streams:
1.
2
3
4
recycling
compost
biofuel production
landfill
EWMC currently recycles or composts __% of all waste- goal is __%
50%
90%
T/F
Edmonton has one of the few e-waste recycling facilities in canada
true!
What happens to the compost sent to EWMC?
- broken down anaerobically by organisms
- biogenic natural gas emissions are collected
sold as “second nature” compost and topsoil around the city
How does biofuel production work at EWMC?
biomass from livestock etc –> gasification (convert C-rich residues into synthetic gas)
then it’s cleaned and purified (ultraclean syngas)
this is very expensive, the city can only maintain it because they make a profit off energy production
The landfill gas from our cloverbar landfill in edmonton can power ___ homes every year!
(don’t need to know this)
4600
only __% of all plastic is recycled
it’s estimated that plastics will outweigh fish in the oceans by ___
14%
2050
Planned Obsolescence=
designing a product with an artificially limited useful life, to force consumers to purchase new products in shorter intervals
- achieved by making products difficult to repair (tech) excessively trendy (fashion) or programming them so they automatically shut off at a prescribed point (ink cartridges stop working when there’s 20% left)
this increases profit for companies
What are the 5 municipal wastewater treatments?
- pretreatment
- primary treatment
- secondary treatment
- tertiary treatment
- quaternary treatment ?
Municipal wastewater treatments:
Pretreatment=
(2 steps)
- aerated grit tank
- remove large, heavy materials like rock - bar screens
- remove large, light material like plastic
Municipal wastewater treatments:
Primary Treatment=
(1 step)
settling tanks
- heavier solids (sludge) settles at bottom of tank
Fate of sludge: fermented, digested, used as fertilizer (depends)
Municipal wastewater treatments:
Secondary Treatment
(1 step)
air out to encourage growth of microbes which degrade organic pollutants
- removes biological nutrients like P and N
Municipal wastewater treatments:
Tertiary Treatment:
(3 steps)
- clarification
- a second set of settling tanks: microbes floc - UV disinfection
- treat effluent w/ UV light to kill any remaining microbes - membrane filtration
- similar effect as UV disinfection
- use micropore filters to remove microbes
Municipal wastewater treatments:
Quaternary Treatment
(&issue)
removal of pharmaceutical pollutants, and other persistent compounds that survive the other treatments
issue= we don’t know how to do it efficiently yet
What are 4 reasons that wastewater goes untreated?
eg=
- equipment malfunction
- overburdened systems like tanks overfilling
- too expensive to do properly
- non-compliance or lack of regulations
eg. Halifax was pumping raw sewage into Halifax harbor until 2008
T/F
climate change does not have an effect on the amount of wastewater that goes untreated
false
- more stormwater= more wastewater
Improperly treated wastewater can contain:
- pathogens
- excess P (eutrophication)
- excess N (disrupts O2 transport in humans)
what can disrupt biological treatment of wastewater?
flushing hazardous waste/ toxins
- disrupt or kill the microbes in secondary treatment
fatbergs=
conglomerates of products that can’t degrade in sewage systems (oils, condoms, diapers, etc)
