8.6 - Thermal Pollution

Question 1

Solubility of Oxygen and Temperature

Answer 1

• Solubility = the ability of a solid/liquid/gas to dissolve into a liquid (oxygen dissolving into water in this case)
• OInverse rel;ationship between water temp and oxygen solubility
  - as water temp going up dissolved oxygen foes down
• Thermal Pollution: when heat released into water has negative effects on organisms living in the water
  - heat increases respiration rate of aquatic organisms (thermal shock)
  - hot water also has less O2
  - This can lead to suffocation without enough O2 to support respiration

Question 2

Sources of Thermal Pollution

Answer 2

• Power plants use cool water from surface/ground water sources nearby to cool steam used to turn a turbine back into water to reuse
• Steel mills, paper mills, and other manufacturing plants also use cool water to cool down machinery & return warmed water to local surface waters
• Urban stormwater runoff can also cause thermal pollution due to heat from blacktop/asphalt
• Nuclear power plants require especially large amounts of cool water to cool steam back into water & to cool the reactor core

Question 3

Cooling Towers

Answer 3

• Cooling towers/ponds are used to cool steam back into water & to hold warmed water before returning to local surface water
• Already standard in nuclear power plants, but can be optimized to cool water better or hold it longer before returning to nearby surface waters