C10

A resource that has a limited supply

An energy source that can be replenished or replaced faster than the rate that it is used

Allows the synthetic production of fertiliser and allows for intensive farming

Water that is safe but not pure

Water that only contains h20 molecules

The sea water has a high energy cost to remove sodium chloride

Rainfall

Insoluble particles are removed using filters beds and then microbes are killed by sterilisation

Ozone, ultraviolet or chlorine

Yes

Using large amounts of energy such as reverse osmosis or distillation

Heats the water until boiling, where evaporated water is collected and leaves the salt

Forces particles through a membrane at high pressure separating non water molecules

Produces lots of wastewater and requires expensive membranes

Removing pollutants from water such as human waste so it can be released safely back into the environment

• Water screened: grit and sticks removed • The water undergoes sedimentation, where heavy solids sink to the bottom • The water is transferred and undergoes aerobic digestion

Undergoes anaerobic digestion and is broken down into fertiliser and methane gas

Requires some degree of judgement

Fewer resources needed to be extracted, less co2 is released as the energy cost of recycling is much lower than that of making a new product

Requires the collection and transport, some materials are hard to sort

Does not require open mining, which leaves scars on the earth

Takes a long time

Uses plants to absorb metal compounds found in the soil. The plants are harvested and turned into ash containing soluble metal compounds. The ash is dissolved in an acid and then is displaced with a more reactive metal

Uses bacteria to produce an acidic solution containing metal ions