The Sustainability Of Current Energy Resource Exploitation- Finite Resources Flashcards
What is sustainability?
Meeting the needs of the present without affecting the ability of future generations to meet their needs
What would make energy sustainable?
Would need to meet our current energy demand without depleting or causing damage that might harm future generations
How do you find naturally occurring fossil fuels?
They are in deposits in the ground
How do coal mines causes environmental damage?
Trees are cut down or burned and the top soil is scraped away
Overburden has to be removed before he seams can be accessed
Mine waste and run-off, this can affect downstream habitats and block river channels
How do mines contaminate ground water sources?
Minerals from disturbed earth can seep into ground water and contaminate them
What is another name for contaminated ground water?
Acid mine drainage
What sort of rocks are ground water sources exposed to?
Sulphur bearing mineral, Pyrite
What is the problem with Pyrite?
It reacted to air and water to form sulphuric acid
Rain cause the acid to get into rivers/streams and even underground water sources
What sort of mining waste can become toxic when exposed to air and water?
Mercury
Arsenic
Fluorine
Selenium
What problems come from the dust form mines?
Can be carried by wind to nearby towns can cause serious health problems
What are the seven ways oil and gas drilling is bad for the environment?
Pollution impacts communities
Dangerous emissions fuel climate change
Oil and gas developments can ruin wild lands
Fossil fuel extractions turns visitors away
Drilling disrupts wildlife habitats
Oil spills can be deadly to animals
Light pollution impacts wildlife and wilderness
What are the upstream (first) stages of oil extraction?
Exploration- seismic surveys, exploratory drilling
Oil filed development and production- drilling, separation, compression
What are the down stream (processing) stages of oil extraction?
Refining- put into needed grades (car fuel)
Transport- pipelines and shipping
Retail & distribution- lubricants, fuels, petrol
What process does crude oil go under for primary separation?
Distillation
What does distillation lead to?
Range of different fractions gases, paraffins and gas oil
What takes place in the secondary conversion process of oil?
Uses heat, catalysts and hydrogen to break down heavy fractions into lighter one like petrol
What is the secondary conversions process also known as?
Cracking
Are their any contaminants form refineries?
Yes a large number of chemicals and additives are used
What are some contaminants from refineries?
Metals, metal compounds, organic and inorganic acids, caustic chemicals, lead compounds, and solvents
What are the processes of coal processing?
Crushing
Screening into different size factions
Physical,chemical or mechanical processes to remove undesired impurities
Dewatering
Thermal drying
Blending
Agglomeration
Why do fossil fuels needs to be transported?
Don’t exist where we need them
What are the problems with transporting fossil fuels?
Increase the rick of pollution/ spills
Increases the cost
Fossil fuels are used to power the transportation methods (ship)
What is an example of an oil spill?
The Exxon Valdez oil spill
What happened at the Exxon Valdez oil spill?
Occurred off Alaskan coast due to tired over worked crew and navigation system glitch
Happened in 1989
Killed 250,000 sea birds, 3000 otters, 300 seals, 250 bald eagles, 22 orcas
What are the benefits of fossil fuels?
Easy to store
High energy density
Useful for high heat processes
Often found in large deposits
Energy density of oil made flight possible
What does conventional extraction mean?
Accessing fuels through standard technology of oil wells, open cast mines or seam drilling
What are the problem with convention extraction methods?
Conventional sources are running out
What in unconventional fossil fuel extraction?
Start looking for harder to access more technically difficult sources
What is the jelly doughnut method?
Old way of drilling
Conventional method
Vertical penetration
Limited formation contact
What is the Tiramisu method?
New way of drilling
Unconventional drilling
Sophisticated horizontal penetration
Extensive formation contact
What is primary oil recovery?
Convention method
Uses pressure of oil/gas to naturally bring the oil to the surface
Once the cap rock has been pierced by the well
What increase the rate of flow for primary oil recovery?
A pump jack
How much oil do you get form the primary recovery method?
Up to 15%
What is secondary oil recovery?
Water is pumped into the well to keep the pressure high
Increasing/ maintaining oil flow
Energy intense but doubles amount of oil recovered
Also possible to pump CO2 down capturing and storing it
How much oil can be recovered form secondary recovery?
20-40%
How much oil is recovered from the tertiary recovery method?
Up yo 60%
What is tertiary oil recovery also known as?
Enhanced oil recovery (EOR)
What is enhanced oil recovery?
Pumping chemicals, microbes or steam
Reduce viscosity of oil so it flows easier
Why are microbes used in EnHanced oil recovery?
Have an added benefit of producing carbon dioxide which helps keep the pressure up maintaining flow
What is directional drilling?
Unconventional method
Wells are drilled that are not vertical
Will bend round to oil in places a drill rig can’t reach (under a town)
What are oil shale and tar sands?
Unconventional oil recovery
Very energy intense
Energy used to heat sand/shale to recover oil
Demand needs to be high to make it economically viable
What are the positives of oil shale and tar sands?
Very large supply
Can produce useable fuels
Efficient recover about 75% of oil
Negative of oil shale and tar sands?
Labelled one of the most destructive processes on earth
Dirty
Only 20% of reserve is easily accessible on the surface ( Canada) rest is 75m below ground
Habitat clearance/destruction
Releases 3x GHG then conventional oil
Where can tar sands be found?
USA
Venezuela
Russia
Canada
What is the average net return of oil from conventional methods?
25:1
You get 25 for every one you use (unit of oil)
What is the net return of energy from tar sands?
5:1 on surface
3:1 undeground
What is hydraulic fracturing?
Long vertical hole (well bore) 2500-3000m
At 2500-3000 horizontal drilling occurs for 1.5km in shale rock
Perforating gun used to make small hole in the rock
Fracking fluid pumped into the pipe at a high pressure it fractures the shale rock allowing gas and oil to escape
What are the benefits of fracking?
Flow back water can be recycled
Gas collected from fracking releases half as much CO2 as coal per unit of energy
What are the issues with fracking?
Uses 3-6 million gallons of water per well (affect local water supply)
Flow back liquid is contaminated has to be stored or disposed of
Recycling of flow back can increase the levels of contamination
Accident scan lead to contamination of ground water
Earthquakes
Methane leaks out during drilling and pumping phase
What is fracking liquid made of?
Mostly water
Acid
Slick water
Disinfectant
Sand or clay
What is coal gasification?
Instead of burning it is chemically transformed into synthetic natural gas (SNG)
What are the positives/negatives of SNG?
Increased gas prices have made in more viable
Transporting gas is cheaper then transporting coal
Coal gasification produces more CO2 than a traditional plant
What is underground coal gasification (UCG)?
Pumping oxygen/steam through a bore hole into a coal seam, producing small controlled combustion
The coal is converted from solid to gas
The gases (hydrogen, methane, carbon monoxide and CO2) are siphoned off
CO2 can be re-injected
Potential net 0
What is coal liquefaction?
Coal is converted into liquid fuels or petrochemicals
What are the steps of coal liquefaction?
Coal is pulverised reacted with catalyst then hydrogen added under high pressure and temp to produce raw liquid fuel
What are methane hydrates?
Crystalline solid that consists of a methane molecule surrounded by a cage of interlocking water molecules
