C10- Using Resources Flashcards
What is the first step in producing potable water in the UK?
Choosing an appropriate source of fresh water
What is the second step in producing potable water in the UK?
Passing the water through filter beds to remove any solids
What is the third step in producing potable water in the UK?
Sterilising to kill microbes
How is desalination carried out?
Desalination can be done by distillation or a process that use membrane such as reverse osmosis. These processes require large amounts of energy.
What are the sterilising agents for potable water?
Sterilising agents used for potable water include chlorine, ozone, or ultraviolet light.
What is a characteristic of chlorine as a sterilising agent?
Chlorine is a toxic gas, so the amount added to water has to be carefully monitored.
What is an advantage of using ultraviolet light for sterilisation?
Using ultraviolet light to kill microbes avoids adding chemicals to the water but is more expensive.
What is reverse osmosis?
Reverse osmosis is a process where sea water is passed through a membrane that only allows water molecules to pass through. It requires high pressure to push the water through the membrane.
What is needed to perform reverse osmosis?
High pressure is needed to push the water through the membrane.
What is a drawback of reverse osmosis?
The high pressure required for reverse osmosis consumes a lot of energy.
How is wastewater produced?
Wastewater is produced by urban lifestyles and industrial processes that generate large amounts of waste water requiring treatment before release into the environment.
What types of wastewater require treatment?
Sewage and agricultural wastewater require the removal of organic matter and harmful microbes.
What does industrial wastewater treatment involve?
Industrial wastewater may require the removal of organic matter and harmful chemicals.
What are the key processes involved in sewage treatment?
Sewage treatment includes screening and grit removal, sedimentation to produce sewage sludge and effluent, anaerobic digestion of sewage sludge, and aerobic biological treatment of effluent.
What is the first step in sewage treatment?
Screening and grit removal.
What is produced during sedimentation in sewage treatment?
Sewage sludge and effluent.
What process follows sedimentation in sewage treatment?
Anaerobic digestion of sewage sludge.
What is the final step in the sewage treatment process?
Aerobic biological treatment of effluent.
What are the stages of Life Cycle Assessments (LCAs)?
- Extracting and processing raw materials
- Manufacturing and packaging
- Use and operation during its lifetime
- Disposal at the end of its useful life, including transport and distribution at each stage.
What is the purpose of Life Cycle Assessments (LCAs)?
To assess the environmental impact of products in each stage of their life cycle.
What is desalination?
The removal of salt from sea water
