Energy

Boundaries in which humans can survive and support future generations

Biogeochemical flows- phosphate and nitrogen. Problem because they help to make soils fertile producing crops for a growing population, phosphates arent renewable. Phosphates and nitrogen also cause eutrophication.

20% of oil is extracted, method uses the pressure of water below the gas/oil to force it up towards the well for collecting

40% of oil is extracted, method pumps oil or natural gas down an injection well to maintain pressure and flow of oil.

60% of oil is extracted, this method reduces the viscosity of oil by pumping steam down an injection to heat oil and adding detergents to reduce surface tension and allow easier flow.

Enhanced oil recovery

Bacteria can be added to digest the heavier hydrocarbons, leaving lighter more viscous oils, the CO2 produced in respiration of bacteria maintains the pressure

A drill which allows many wells to be produced from one hole

Allows drilling under areas where drilling rigs could not be built, like urban areas A higher oil recovery rate because the drills can follow soft rock which allows faster drilling

Heavy low viscosity oils

Solid hydocarbons

Sand is heated with hot water, this produces emulsions of oil droplets which can be separated and collected. Has a 75% recovery

Oil shales are mined then the oil is extracted by heating the shales to drain off the liquid hydrocarbons.

Carbon capture and storage, a method of storing CO2 from fossil fuels by pumping it underground into empty spaces

Uses high pressure to open fissures in the surrounding rock which allows oil/gas to flow towards recovery well. Water, sand or solvents can be added to increase recovery rate.

Used on tight oil or gas.

Oil/gas that is trapped in pores of rocks with low permeability

Natural gas entering aquifers Chemicals entering aquifers Toxic metals becoming mobile large volumes of water are used earthquakes more common due to tension

Coal too deep to be mined is burnt underground. This produces a mixture of fuel gases, like methane, hydrogen and carbon monoxide

The conversion of coal to liquid hydrocarbons. Coal can be converted directly with solvents or indirectly by conversion to gas then it can undergo chemical changes to a liquid

Solid, ice-like crystals found in cold regions or high pressure regions

Water heating Depressurisation Co2 injection

Hot water is pumped into sediments to melt the hydrate crystals which release methane

Drilling into hydrates to decrease the pressure, this allows the methane to gradually dissociate