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1 The properties of economically important Earth materials formed from organic material
distinguish between the nature of renewable and non-renewable resources
process information from secondary sources to classify renewable and non-renewable resources commonly in use
identify data sources, gather information and perform a first-hand investigation to identify and classify a variety of fossil fuels commonly used and compare their properties and uses
assess estimates of known reserves of non-renewable resources in light of technological innovation
define fossil fuels as ‘useful organic-matter-derived Earth materials’
describe the changes in coal with increasing rank in terms of:– physical properties
– composition
– grade– energy yield
describe properties of liquid petroleum in terms of composition and energy yield
describe properties of gaseous fossil fuels in terms of composition and compare the energy yields of coal-derived gas and petroleum-derived gas
Renewable and Non Renewable- Renewable: can be replaced over a relatively short time
o For example solar and wind - Non renewable: are non renewed quickly – may take millions of years. When they have
been used they are effectively depleted as they take millions of years to be producedo For example coal and petroleum take many years to form
Fossil fuels are – useful organic matter derived earth materials
Estimates of known reserves for non renewable resources
- Coal is Australias largest energy reserve- At the current rate if usage the energy reserves lifetime in Australia is
o Coal – 176 yearso Natural gas – 63 yearso Oil – 14 yearso Uranium – 67 years
- The global reserves lifetime (2007):o Oil – 42 yearso Natural gas – 60o Coal – 133 yearso Uranium – 70 years
Type Carbon Content Properties Sulfur Content Energy Yield MJ/kg
Peat 60% Volatile matter (higher the more flammable)– 60%Looks leafy and relatively greenmoist
Variable 15
Brown Coal (lignite)
60 – 71% Volatile Matter 53 – 49%Brown moist
1% 25
Sub bituminous 71 – 77% Volatile Matter – 40%Many volatilescrumbly
0.2 – 1.2 % 30 – 35This coal is used in electricity
Bituminous 77 – 87% Volatile Matter – 15 – 30%Crumbly, some shiny parts black volatiles
0.3 – 1% 35Electricity
Anthracite 94% Volatile Matter – 5%Shiny – pure anthracite is totally shiny and smooth
0.7% 35Not energy efficient as a very low volatile matter
Rank and grades of different coals
Properties of liquid petroleum
Crude oil State Energy Yield MJ/kgNatural Gas Gas 49 - 55Petrol Liquid 48Kerosene Liquid 53Diesel Liquid 54Heating oil Liquid 54
Gaseous fossil fuels derived from coal and petroleum
Coal- Previously coal was processed the produce Syngas, a mixture of carbon monoxide and
hydrogen. - Syngas, however, has a low energy yield of around 9kj per cubic metre- A more common gas derived from coal is coal seam gas (coal methane) with an energy yield
of around 40kj per cubic metre- Methane is produced as a bi product of the coalification process, in the pores of the coal
exist pores, the pores in the Sydney basin are roughly 95% methane (high composition)- To recover the methane boreholes are drilled into the coal seam, water is then removed
from in the coal reducing pressure allowing methane to escape through fractures from which it can be pumped to the surface
Petroleum- Natural gas is formed in petroleum- Natural gas produces about 39 kj of energy per cubic metre burnt- Liquefied petroleum gas (LPG) produces about 105 kj of energy per cubic metre burnt
2 The environment, and process of coal and petroleum formation
outline the characteristics of coal-forming environments
analyse information from secondary sources, including resource maps, to: – identify coal-producing
localities
– identify petroleum-producing localities
gather and process information from secondary sources to analyse the similarities between environments in coal- and petroleum-producing localities
discuss the process of coalification — transforming vegetable matter into peat and coal
describe the characteristics of petroleum-forming environments
outline the maturation of petroleum — diagenesis, catagenesis, metagenesis
outline the process of oil and gas migration
describe the features of source rocks, reservoir rocks and cap rocks
analyse the conditions under which petroleum accumulates in structural and stratigraphic traps
Coal forming environments
- Coal forms in swampy areas with high vegetation- The swamps are stagnant – very little oxygen present, which stopped bacteria being present- The plant matter took a long time to partially decay forming peat
Coalification
- Coal forms its different grades and rank through coalification- Coalification involves increasing heat and pressure to form peat, brown, sub bituminous,
bituminous and anthracite- For Peat some pressure is needed- Brown an increase in heat and pressure- For Sub Bituminous – bituminous intense pressure and heat is needed- For anthracite often metamorphism takes place with extensive heat/pressure
Petroleum forming environments
- Geologists believe for petroleum to form there needs to be high global sea levels- Marine organisms such as plankton fall to the sea floor where they are buried by
sedimentation- Over millions of years the marine organisms decay into simple organic compounds whereby
heat and pressure transform the compounds into oil
Maturation of petroleum including
Diagenesis Catagenesis Metagenesis
Diagenesis
- Occurs from the surface of the depositing sediment to depths of a few hundred metres- Temperature of about 50o C and pressures more than 1000 atmospheres- Biogenic methane forms
Catagenesis
- Occurs at depths from 1km to about 3.5 – 5km - Temperatures 50 – 150o C- Pressures of 1500 atmospheres- This brings about the compaction of rock and expulsion of water - Organic matter is altered to produce liquid petroleum and kerogen
Metagenesis
- Below depth of 3.5 – 4km temperatures exceed about 150oC and pressure is about 1500 atmospheres
- Under these conditions early stages of metamorphism take place to the organic matter - Organic matter is converted to natural gas
Depths Type Result
0 – 1km Diagenesis
(immature zone)
Biogenic methane
1 – 3 Catagenesis
(oil zone)
Petroleum
Kerogen
3 - 4 Catagenesis and metagenesis
(wet gas zone)
Some possible oil deposits
Mainly natural gas
4km onwards Metagenesis Natural gas
(dry gas zone)
Oil and gas migration
Source rock – The rock in which the oil forms in
Migration – The process of oil and gas moving through pores in the sedimentary rock and upward towards the earths surface
Reservoir Rock – The rocks in which the oil is trapped
Cap rock – Impermeable rock which traps oil and gas
Trap – The resulting geological formation of the cap rock
- Most petroleum never reaches the surface- The hydrocarbons are typically trapped beneath the surface of impermeable rocks (cap
rocks) that are typically above the Source rock- As the hydrocarbons move upwards they displace sea water trapped in the sedimentary
rocks- When the hydrocarbons reach the cap rock they separate with the least dense gas going to
the top and the oil and sea water with the highest density at the bottom - There are two main types of traps: structural traps and Stratigraphic trap- Structural
o Caused by the folding or deformation of layers of rocko Can be either anticline or fault traps
- Stratigraphic trapso Change in the physical properties of the reservoir layer itselfo Could occur when sediments allowing petroleum to move through it become highly
compacted or pores decrease in size
Copy Diagrams pg 262 of Earth and Environmental science textbook
3 Searching for coal and oil describe the exploration methods
used to determine the existence and extent of coal deposits
gather information from secondary sources to outline the methods and technologies used to locate fossil fuel reserves
describe the exploration methods used to determine the location of oil, including geophysical methods and drilling
identify the location and main geological features of known coal and oil localities and relate this to the search for new ones
Exploration of coal deposits
- There are seven phases that make up the exploration of coal
Identification of a likely area obtaining legal license Gathering information through exploration evaluation of a deposit development of the mine extraction of the resource closure and rehabilitation
- Identification of a likely areao Involves developing knowledge of the areas geology which would indicate if there
are coal depositso NSW department of mineral resources and Australian Geological survey organisation
play an important role in providing basic information about areas- Obtaining legal license
o In Australia a license is required to explore an area prior to extraction o This license is obtained through the government and is usually always given, unless
another company owns the rights to an area of land- Exploration
o Involves mapping the areaso Buying land from landowners
- Evaluation of the deposito Involves the use of geophysics and geochemistry to determine more information
about the areao Geophysics
Magnetic methods – Geophysicists can map the magnetic field of a an area as different rocks have a different magnetic behaviour
Seismic methods – involve creating a shock wave which travel into the earth and recording them when they return to the surface. The waves hit boundaries and are reflected back to the surface. An accurate cross section of the area can be produced
Resistivity – measures how well a rock conducts electricity. Coals do not produce electricity
o Geochemistry Some potassium atoms are radioactive and produce radiation in the form of
gamma rays which can be measured through a gamma ray logger By measuring the natural gamma rays in a rock it is possible to determine
the rock typeso Assaying will also take place whereby a sample is collected and analysed to
determine its grade and quality o Through exploration companies can determine if the mine is going to be
economically viable o Companies also determine a way to mine the area and thus work out if the mining
itself is economical- Development of the mining site
o Infrastructure such as roads developedo Transport built up such as ports and airports
- Extractiono Coal/ore is extracted o Further deposits may be located during this timeo Environmental monitoring
- Closure of the mining siteo Under Australian law it is necessary to rehabilitate a siteo Companies such as Rio Tinto will do so regardless
Exploring oil and extracting
- Similar to coal
Identification of a likely area obtaining legal license Gathering information through exploration evaluation of a deposit development of the mine extraction of the resource closure and rehabilitation
- Similar to mining – see above- Exploring
o Assaying may take placeo If the geology of the area is known then possible geological structures such as
anticlines may have oilo Geophysics (seismic waves, resistivity) may be used o Rock samples give detailed information about the rock layers that the drill will pass
through
Identify the location of known coal and oil deposits and relate them to the search for new ones
- Similaritieso Both require anaerobic conditions with organic matter
- Coalo Coal in Australia is found in areas such as the Sydney Basin, New England Fold belt
and Gunnedah basino These areas all were swampy and had oceans nearby to compress sedimentationo Therefore, an area which previously had large volumes of water nearby as well as
swamps could potentially have coal- OIl
o Required a shallow oceanic environment to be in the area o Anticlines and faults are possible locations for oil and gas
- Conodont indexo Conodonts are extinct sea creatures that lived during the carboniferous (when most
fossil fuels formed)o Conodonts are found in the same rocks that oil and gas are found in and depending
on the level of heating of the rock based on metamorphic activity the remains of the conodonts will change colour
o If the rock is not heated, no fossil fuels are formed (condont index of 0 – 0.9) o If the rock is slightly heated (Conodont index 1-2) then oil could formo If the rock is very heated (conodont index 3-4) then gas could form
4 The uses of coal and oil
describe the refining of coal gather and present information from secondary sources to construct flow charts and diagrams of the processes used in refining fossil fuels
describe the refining of petroleum, including distillation and catalytic cracking
describe and evaluate the uses of coal and oil as fuels and raw materials for industry
The uses of coal and oil
Description of the refining of coal Description of refining of petroleum Evaluation of uses of coal and oil
- Refining of coalo Coal can be used without any processing, screening and crushing is often used just
only in order to reduce it to a useable sizeo Coal usually is washed to remove pieces of rock and minerals o The methods for washing vary from mine to mine and include sink – float
separation, froth flotation and shaking tables and are either physical, chemical or biological
Sink – float separation (physical) – crushed coal is added to a high density liquid in which it floats and can be recovered while the heavier rock and minerals sink and are discarded
Froth flotation (chemical) – The coal is chemically treated to stick to bubbles and floats to the surface to be skimmed off. The coal and bubbles are then separated. Inorganic matter sinks to the bottom of the tank
Chemical cleaning – used to remove organic sulfur combined with carbon in coal
Biological cleaning – involves using bacteria to eat off the sulfur on the coal Shaking tables – coal and waste rocks placed on a corrugated incline
allowing for separation between waste and coalRefining of petroleum
- Every refinery begins with the separation of crude oil by distillation into different parts called fractions
- These fractions are later treated to convert them into mixtures of high demand products- The main task of most refineries is to produce petroleum- There are two processes which are used to develop low demand fractions into high –
demand petrol including:o Distillationo Catalytic cracking
- Distillationo Because crude oil is a mixture of hydrocarbons with many different boiling points it
can be separated by distillation into groups of hydrocarbonso Distillation takes place in two stages including atmospheric and vacuum distillationo Atmospheric distillation
Takes place in a distillation column at or near atmospheric pressure The crude oil is heated to 350 – 400 o C and the water vapour and liquid are
piped into the distillation column The liquid falls to the bottom and the vapour rises whilst it passes through a
series of perforated trays The heavier hydrocarbons with lower boiling points settle on lower trays,
whilst the lighter hydrocarbons remain as vapour longer settling on the higher trays
Some light gasses such as methane, ethane and propane which pass out the top and do not settle on trays
Petrol is collected in the top trays, gas oils in the middle and fuel oils at the bottom
o Vacuum distillation
This occurs to process the heavier oils that collects at the bottom of the atmospheric distillation process to be processed into lubricating oils, waxes and bitumen
Vacuum distillation allows heavy hydrocarbons to be separated without producing unwanted bi products
o Catalytic cracking Used to convert the heavy hydrocarbon fractions obtained by vacuum
distillation into more useful products The large hydrocarbons undergo a chemical breakdown under heat and
pressure from a catalyst (a substances that causes a reaction without being chemically changed itself)
o Catalytic re – forming Is a process that used heat, pressure and catalyst to bring about chemical
reactions that produce a higher octane petrol
The uses of coal and oil for fuel and industry
Coal PetroleumSteaming – Heat for electricity generation Fuels - transportationDomestic – Heating, shampoos and medicine Lubricants – Oil, Vaseline, GreasesCoking – Steel production Industrial – Packaging, plastics, rubber, bitumenDistillates – Explosives, dyes, plastics Domestic – Fabrics, adhesives, paint, plastics,
synthetic rubberFuel – Coal gas Military – defoliants, incendiary devicesOther industrial – soaps, rubber
Advantages and disadvantage of coal
- Advantageso One the most abundant resources in the world as well as one of the least expensiveo Much higher energy potential then renewable resources such as solar and windo High amounts of coal in Australia making it ideal for Australia as Australia has less
other resourceso Coal reduces the reliance on oil and natural gas which are decreasing at an alarming
rate- Disadvantages
o It is non renewable and at the current rate will be depletedo It produces harmful air pollution such as CO2
Advantages and disadvantages of Oil
- Advantageso Highly combustible and high energy yieldo Large amounts of energy can be produced to power a large area from one small
locationo Oil is easily accessible through easy transportation
- Disadvantageso Rapidly depleting
o Produces large quantise of harmful CO2 emissions o Price of oil is rising
5 The environmental impacts of fossil fuel use – complete versus incomplete combustion
analyse and evaluate the types and effects of products of burning fossil fuels – gases, water, particulates
identify data sources, select equipment, plan and perform a first-hand investigation to distinguish between the products of complete and incomplete combustion
identify data sources, analyse information and use available evidence to determine the effects of fossil fuel combustion products, using a variety of media
analyse information and use available evidence to predict the economic and environmental effects of removing all sources of fossil fuels
analyse the dependence of modern society on fossil fuels and assess attempts to limit emissions
describe and evaluate arguments concerning the greenhouse debate
Evaluation of:
Types and effects of burning fossil fuels
- Fossil fuels used in electricity, transport and the production of raw materials produce vast amounts of pollution
- Carbon Dioxide (CO2) Nitrous Oxide(NO), Water Vapour, Methane (CH4), Carbon Monoxide (CO), Sulfur Dioxide (SO2)
- The burning and combustion of coal, petroleum and gas all produce Carbon dioxide other gases such as carbon monoxide mainly form as a result of burning fossil fuels such as in incomplete combustion
- Carbon Dioxide, Water Vapour, methane and Nitrogen oxide are all greenhouse gases which cause global warming
o During the 20th Century the average temperature of the globe increased by 0.58o Co Sea levels have risen between 0.1 – 0.25 metres in the last hundred years
- Sulfur Dioxide (burning of coal) and nitrous oxide are causes of acid raino Potentially damaging to agriculture and environmento Health risk
- Particulates mostly dust, soot and unburnt coal are released into the atmosphere by burning fossil fuels
o Very small particulates can be inhaled and penetrate the long causing respiratory illnesses as well as sometimes a reduced life expectancy
- These issues come as a cost to society (especially health related issues)- They cause the potential for the melting of ice caps and flooding of island nations- Cost to agriculture and primary industries associated
Dependence on fossil fuels
- Traditionally society has been highly dependent on fossil fuels as a means for transportation, energy and the use of raw materials such as plastics
- Whilst this is still very much true, this dependence is decreasing as more alternative sources become increasing viable
- At present fossil fuels are the only real option for energy, as alternatives have not quite reached the point where they can be implemented, however, at the current rate, with new research being committed to alternatives then in the future alternatives pose a real possibility
- Government agencies fund research into fossil fuels - There has been the implementation of schemes such as the solar rebate as well as wind
turbines in NSW- Australia is a signatory to the Kyoto protocol which aims to reduce greenhouse gas
emissions- The Federal government recently passed the carbon tax which aims to bring about clean
energy in industries- There are emission standards for cars
For greenhouse debate – see Caring for the country
Complete and incomplete combustion
- Completeo With excess oxygen, hydrocarbons combust (burn) to produce carbon dioxide gas
and water vapour
- Incompleteo With insufficient oxygen present, hydrocarbons combust (burn) to produce carbon
monoxide gas, solid carbon or both as well as water vapour
Fossil Fuel + oxygen Heat + Carbon dioxide + water vapour
Note : Some oxygen is still needed
6 The search for alternative sources of energy
identify and discuss alternative sources of energy — solar, wind, hydro-electric, nuclear, synthetic oil, ethanol, wave power — and evaluate the relative importance and future potential of each as an alternative energy source for local communities
gather information from a secondary source to investigate alternative sources of energy
solve problems and perform first-hand investigations to test the energy efficiency of various non-fossil fuels and alternative energy sources
describe and evaluate methods of conserving energy, including architectural design
Alternative Fuel Sources
Solar
- Thermal o Produces heated water o UV enters a small glasshouse and absorbs heat
- Solar electricityo Photovoltaic cells are layers of silicon semiconductors producing voltage
- Positiveso No greenhouse gases producedo Renewable energy sourceo Cost effective in country areas, not close to major power stationso Competitive price to other renewable energy sources
- Negativeso No sun – powero Expensive option at presento Damaged in poor weathero Does not produce a great deal of power ie it could not power a city
Wind
- Wind carries kinetic energy which moves the wind turbine leading to a rotor powering a generator through the spinning motion
- Positiveso No greenhouse gases
Fossil Fuel + Oxygen heat + Carbon + water vapour + Carbon monoxide
o Renewable energyo Competitive price to other renewable energy sources
- Negativeso Aesthetic problemso Noisyo No wind – no powero Cannot power an entire city
Hydroelectricity
- Flowing water is fed down a pipe where It causes turbines to spin which power a generator- Positives
o No greenhouse gaseso Renewable energyo In most cases there is always flowing water
- Negativeso Interference with environment and natural flowso Very dependent on terrain, needs a hilly environmento Could not power a whole state or city, ie the snowy mountain hydro electric scheme
– the largest engineering project ever undertaken in Australia produces only 10% of NSW energy
Nuclear
- Fission o Splitting of the nuclei of large atomso A mass defect occurs with the loss of the neutron, this loss is released in energyo 1kg of uranium = 2000kg of coal
- Positiveso Little costs are requiredo No greenhouse gases producedo High energy output
- Negativeso Radioactive waste is produced which must be disposed ofo Potential for meltdown causing radiation problems across a wide areao Uranium is not renewableo Very expensive
Synthetic oil
- Fuels such as petroleum can be produced from coalo Coal is crushed at high temperatures and pressure in the presence of a catalyst to
produce hydrocarbons- Positives
o Can be used in the current built up industries and transport- Negatives
o Non renewableo Production is inefficient
o Greenhouse gases
Ethanol
- Produced from the process of fermentation or from petroleum- Fermentation is yeast converting sugar to ethanol- Competing with hydrogen as fuel of the future
- Positives
o Energy efficiento Renewable energyo No excess CO2 emissions as same amount released as was taken from the
vegetationo Decreasing price making it quite competitive
- Negativeso High energy required to produce ethanol only 20% more released than required to
make ito More farmland is required than what is currently requiredo Cars would need to be modified
Architectural design
- Windows allowing high amounts of natural light- Installing better insulation
o 10 – 20 % heat is lost through the floor- Sidusis trees
o Shade the house during summer and when winter comes their leaves fall off so sun can come
- Double glazing on windows- Gas heating produces less greenhouse gases- Wearing warm clothes- Solar thermal and power- Energy efficient shower heads- Keep fridge away from stoves
o 100kg less emissions- Turn standby mode off on TV’s and computers- Fluorescent lights use 80% less energy- Use compost