exam 2 Flashcards
1
Q
fossil fuels
A
Combustible deposits in the Earth’s crust composed of the remnants of prehistoric plants from the carboniferous period. carbon rich
2
Q
coal pros
A
easy to transport, abundant
3
Q
coal cons
A
non-renewable, most air pollutants(CO2, NOx, SOx, mercury), acid rain, most ecosystem damage
4
Q
subsurface coal mining
A
Extraction from deep, thick underground deposits. Mineshafts
5
Q
hazards of subsurface mining
A
coal dust (lung disease), mine collapse and explosions, fires, toxic fumes like carbon monoxide
6
Q
pros of subsurface coal mining
A
less environmental destruction but releases more toxins
7
Q
cons of subsurface coal mining
A
more dangerous, more expensive, more human labor, acid mine drainage
8
Q
acid mine drainage
A
toxins from coal such as sulfur, wash from mines into water. lowers the ph of water.
9
Q
surface coal mining
A
extracting coal deposits near earths surface by removing soil, subsoil and rock. ex: mountaintop removal and strip mining
10
Q
overburden
A
removing all rock, dirt, and organic matter to uncover a mineral deposit
11
Q
mountaintop removal
A
overburden placed in valleys blocking streams. landscape is permanently altered.
12
Q
bioaccumulation
A
the buildup of a persistent substance in an organism’s body; more exposure means more buildup
13
Q
biomagnification
A
amt of substance per organism increases with each successive trophic level
14
Q
what can water contamination from acid mine drainage lead to
A
decreasing biodiversity: leads to bioaccumulation and biomagnification
15
Q
pros of surface coal mining
A
cheaper, safer, less labor
16
Q
cons of surface coal mining
A
much more environmental damage
17
Q
coal processing
A
coal must be washed in streams to isolate coal from other chemicals. creates coal slurry.
18
Q
byproduct of coal processing
A
coal slurry
19
Q
Surface Mining Control & Reclamation Act (SMCRA)
A
reclamation of surface mines, permits and inspections required, protection of sensitive lands
20
Q
acid deposition
A
acid rain
21
Q
coal ash
A
fine particles leftover from burnt coal containing silica and toxic metals.
22
Q
what is done with coal ash
A
- recycled into concrete or construction fill
- buried in hazardous waste landfills
- stored in ponds like slurry
23
Q
clean coal technology
A
Reduces the amount of pollution produced by burning coal. Fewer NOx and SOx, extra processing before combustion. scrubbers remove SOx
24
Q
T or F: clean coal tech still causes pollution
A
true
25
petroleum
oil composed of hydrocarbon compounds
26
Reserves
the amount of a fuel that is economically feasible to extract from a deposit using current technology
27
Peak Oil
the point at which global oil production is at its maximum rate
28
oil production 3 steps
1. initial release of pressure forces oil up
2. water injection
3. CO2 injection
29
Petroleum refining
separating compounds by boiling point
30
oil cons
CO2 emissions/greenhouse gases, water pollution, acid rain, spills and explosions, habitat loss
31
natural gas
HC compounds, mostly methane
32
natural gas pros
cleanest burning fossil fuel
33
fracking
using controlled explosives and pressurized fluid to force oil/NG from porous rock
34
natural gas cons
expensive and dangerous transport, acid rain but no NOx or SOx, air pollution, CH4 (methane) emissions
35
tar sands/synfuels
Underground sand deposits permeated w/ thick asphalt like oil
36
tar sand/synfuel cons
uses more water, emits more greenhouse gases CO2, habitat destruction, risky extraction and transport, not efficient
37
what are the 3 synfuels
tar sand, oil shale, gas hydrates
38
What is the current state of Carbon Capture and Storage (CCS) technology for use in coal power plants?
CCS technology is being implemented on a small scale and is still very costly
39
How has the burning of fossil fuels affected the global carbon cycle?
Less carbon is stored underground
40
Atom
smallest portion of an element that retains its chemical properties
41
Atomic Number
total number of protons, on top
42
Atomic Mass
total number of protons and neutrons, on bottom
43
Isotopes
Atoms of the same element that have a different number of neutrons
44
Chemical Reaction
1. mass of start and end products are equal
2. mass isn't converted to energy
3. elements remain unchanged
4. energy comes from released chem bonds between atoms
45
nuclear reaction
1. mass of end product is slightly less than start
2. small amt of matter converted to huge amt of energy
3. atoms of one element change into another
4. energy released comes from conversion of matter to energy
46
nuclear fission
splitting an atom's nucleus
47
nuclear fusion
joining 2 atoms nuclei
48
nuclear fission steps
1. fast moving neutron hits nucleus and splits it
2. releases 3 fast moving neutrons and heat
3. domino effect
49
how is a nuclear fission domino effect stopped
control rods absorb neutrons. takes place in a containment building.
50
Radioisotope
isotope that spontaneously emits radiation.
51
Radiation
energy consisting of alpha & beta particles and gamma rays
52
Radioactive decay
the emission of particles from unstable atomic nuclei
53
what is the fissionable isotope in uranium ore
U-235 (1% of ore)
54
uranium milling
Ore is crushed & mixed with acidic or alkaline solutions to separate out the uranium
55
uranium enrichment
the process by which uranium fuel is refined to increase the concentration of U-235
56
uranium fuel production
packaging enriched uranium fuel into pellets
57
what powers fission reactions in nuclear power plants
U-235
58
what happens after the fission reaction in a nuclear power plant is triggered
fission reactions generate heat to turn water into steam to generate electricity. river/ocean water is used as a coolant to condense steam back into water.
59
low level radioactive waste (LLRW)
can be safely buried. Nuclear power plant clothes & tools, nuclear medicine, research labs. 3 storage sites in US.
60
high level radioactive waste (HLRW)
Spent fuel rods & assemblies, reactor water, or nuclear weapons waste that is still highly radioactive. stored onsite at power plant. 100,000 years of storage.
61
Vitrification
solidifying high-level liquid waste (like reactor water) into solid glass or ceramic logs
62
Temporary storage solutions in NPPs
Under water storage (indoor pools)
Above ground concrete & steel casks (dry cask)
63
what is done when NNPs are shut down
they can't be abandoned, must be decommissioned
64
nuclear energy pros
carbon free, no direct air pollutants, equally productive at all times, energy rich, reserves last a long time
65
nuclear energy pro/con
spent fuel can be recycled into plutonium but US doesn't recycle bc it can be used for weapons
66
nuclear energy cons
meltdowns are rare but dangerous, spread of radiation after meltdowns is large and unpredictable, health effects like cancer and deformities, no long term storage plan, mining and processing degrade envt
67
3 big nuclear accidents
chernobyl, 3 mile island, fukushima
68
Spent fuel is
radioactive waste generated by nuclear energy production
69
Renewable Energy
E from renewable sources that are replenished over short time scales or that are perpetually available
70
Sustainable Energy
E sources that have a low environmental impact
71
Passive solar heating
A system that harvests the sun’s energy without using mechanical devices to distribute heat
ex: solar cookers, double paned glass in houses
72
Active Solar Heating
A system that harvests the sun’s energy and uses pumps or fans to distribute the collected heat. typically used to heat water. ex: solar panels
73
Solar Thermal Electric Generation
A system that uses mirrors or lenses to concentrate the sun’s energy onto a fluid/panel that is used to generate electricity
ex:solar power towers
74
Photovoltaics (PV)
Method of converting sunlight directly into electricity using materials that readily give up electrons. no turbine used
75
Solar/PV Cells
thin film treated with metals so that it generates electricity when it absorbs solar E.
ex: solar panels
76
Biomass
Chemical E stored in the form of organic matter. oldest fuel. ex: wood, biogas digester
77
solar energy pros
reduces FF dependence and cost competitive with other energy sources
78
solar energy cons
availability varies with time of day and season
79
biomass pros
reduced FF dependence, can use waste, burns cleaner than FFs
80
biomass cons
air pollution, land and water use, currently using biomass faster
than regeneration time
81
Wind Energy
Electric energy obtained from winds caused by solar heating of the air. indirect solar energy
82
how do wind turbines work
wind turns blades, spinning powers generator, and electricity sent to cables
83
Wind Pros
no air pollutants, reduced FF dependence, cost competitive
84
wind energy cons
strongest winds are in remote areas, kills birds and bats, nimby
85
Hydropower
electric energy obtained from flowing or falling water. dams
86
Hydropower Process
water flows and spins the turbine connected to generator
87
hydropower pros
no air pollutants, reduced FF dependence, flood control, irrigation, navigation
88
hydropower cons
ecological disruption in stream and reservoir, possible seismicity, Evaporation & salinity, soil infertility, Electricity production declines as sediment builds up, displacement, cultural loss, water borne diseases, methane from dead plants
89
what devices help fish move up dams and avoid turbines
fish ladders and bypass systems
90
Wave power
Electricity obtained from the movement of ocean waves. indirect solar energy
91
Ocean thermal energy conversion
(OTEC)
Using ocean temperature gradients to produce electricity or cool buildings. indirect solar energy
92
In the United States, solar radiation is greatest in:
southwest
93
Tidal Energy
uses flow of tides to generate electricity.A large difference between Hi & Lo tide is required to generate electricity.
94
tidal energy process
energy from moving water during the tide going in spins a turbine and generates electricity
95
tidal energy pros
no air pollutants, reduced ff dependence, predictable
96
tidal energy cons
species migrations, erosion, storm damage, nimby, intermittent electricity gen.
97
Geothermal Energy
Heat stored underground, contained in either rocks or fluids
98
geothermal energy process
hot fluid is pumped and generates steam, steam spins turbine and is then cooled and condensed
99
geothermal energy pros
no CO2, reduced FF dependence
100
geothermal energy cons
H2S emissions, water depletion, sinkholes, limited to areas with recent volcanism
101
Geothermal heat pumps
use temp difference between surface and subsurface to heat and cool buildings. epa approved but expensive
102
Energy Services Companies
set up contracts with companies to find ways for companies to save energy and money. money saved is used to repay them.
