Topic 10: Oil Pollution

Question 1

Give 3 causes of oil pollution

Answer 1

Waste lubricating oil
Accidental release
Oil exploration

Question 2

Explain where waste lubricating oil that is a cause of oil pollution, comes from?

Answer 2

Vehicle engines lubricating oil either leaks or is discarded deliberately into the environment
Industrial machine oil which is washed into drains or mixed with other effluents

Question 3

Where can accidental releases of oil come from?

Answer 3

Shipping accidents, especially oil tankers
Oil rig accidents
Oil pipeline leaks
Leakage from storage tanks
Discharge of waste water from washing tanks on ship tankers

Question 4

How does oil exploration lead to oil pollution?

Answer 4

Drilling
Drill pipes are lubricated with fine clay suspended in water to reduce friction when they bore through rocks
Sometimes oil based clays are used

Question 5

How can oil pollution affect organisms that live on or in the water?

Answer 5

• some components of crude oil are toxic like benzene and xylene, planktonic organisms are most likely to be affected
• oil can cover aquatic life on sea surface
• this can lead to the asphyxiation of molluscs and crustaceans
  Algae on the seashore would be unable to absorbe the reactants for photosynthesis

Question 6

How can oil pollution affect birds ?

Answer 6

Severe oil covering can cause them to drown
Oil can stick their feathers together so they lose insulating properties and can die of hypothermia
They might try and clean off a small amount but that can reduce the time available for finding food for them and their young

Question 7

How can oil pollution affect aerobic organisms?

Answer 7

It can form a thin layer on water which reduces the amount of oxygen that can dissolve in water from atmosphere which can reduce the survival of aerobic organisms there

Question 8

How can marine organisms be affected by oil pollution?

Answer 8

The masking odour and narcotising effects of oil can make it more difficult for marine organisms that use their sense of smell to find food and mates

Question 9

Give 5 ways that oil pollution can be controlled

Answer 9

Prevention of oil releases
Improved oil tanker operation
Improved tanker design
Oil interceptors
Bund walls

Question 10

Explain how oil releases can be prevented in order to control oil pollution

Answer 10

By recycling waste lubrication oil
Contaminants can be removed, chemical reforming and distillation can produce chemically valuable lubricants again

Question 11

How can oil tanker operation be improved to control oil pollution?

Answer 11

Better shipping routes
Better navigation systems
Inert gas systems
Tank washing procedures
Oily waste water disposal

Question 12

How can better navigation systems improve oil tanker operation?

Answer 12

The AIS (automatic identification system) allows the position of the ships to be monitored and coordinated to help avoid collisions

Question 13

How can tanker design be improved in order to control oil pollution?

Answer 13

Double hull
Twin engine/rudder/fuel tanks
Seperate oil and ballast tanks

Question 14

Why is double hulls an example of improved tanker design?

Answer 14

It makes any damage to the hull of the ship less likely to release oil into the sea

Question 15

What are oil interceptors and how can they control oil pollution?

Answer 15

They seperate oil from watery waste e.g from drainage water from major roads or from car parks
The water still flows into main drainage system or river but is retained and can be removed for later treatment

Question 16

What happens to oil that is spilt in turbulent conditions in open water?

Answer 16

Most is dispersed in a few days or weeks
Lighter fractions can evaporate
Medium fractions will gradually be digested by bacteria
Heavier fractions might remain as tar balls for years

Question 17

When is oil pollution most serious?

Answer 17

When it occurs inshore or in an enclosed body of water because dispersal is prevented
Areas with more sensitive ecosystems

Question 18

Give 7 ways that oil spills can be treated

Answer 18

Booms
Skimmers
Absorbent materials
Detergents/dispersants
Polymerising agents
Steam washing
Bioremediation

Question 19

What are booms and how can they be used to treat oil spills?

Answer 19

They are inflatable tubes that restrict the movement of floating oil
A ‘skirt’ below can retain oil if there is a water current

Question 20

Where can and cant booms be used?

Answer 20

They dont work in open water where currents/waves are too strong
Mainly used in sheltered areas where they can reduce dispersal of oil from the pollution source or protect sensitive sites

Question 21

What are skimmers and how can they be used to treat oil spills?

Answer 21

They are rotating metal discs that pick up oil that can be scraped off and stored for later disposal by incineration or landfill

Question 22

What are absorbent materials and how are they used to treat oil spills?

Answer 22

High surface area materials like textile mops can help absorb oil
The absorbent material and oil can be removed and disposed of by incineration or in landfill sites

Question 23

What are detergents/dispersants and how can they be used to treat oil spills?

Answer 23

They break up the oil to produce an emulsion of oil droplets in water
They allow oil to become more mobile and disperse, possibly to be broken down by bacteria
But they dont reduce amount of oil pollution

Question 24

How are detergents and dispersants spread?

Answer 24

At sea by aircraft and ships
Using backpack sprayers on the shore

Question 25

What are polymerising agents and how are they used to treat oil spills?

Answer 25

Chemicals have been developed that cause oil molecules to join together
This produces more solid materials that can be collected more easily

Question 26

What is steam washing and how can it be used to treat oil spills?

Answer 26

Used to wash oil on beaches off
It doesnt destroy it but removes it from particularly sensitive habitats

Question 27

What is the issue with the steam jets in steam washing?

Answer 27

They may kill organisms deeper in beach sediments that weren’t affected by the oil

Question 28

What is bioremediation and how is it used to treat oil spills?

Answer 28

Some bacteria breakdown hydrocarbons and help remove the residual pollution left after other clean up methods are used

Question 29

when may bioremediation be accelerated?

Answer 29

Higher temperatures, oxygen and nutrient levels