Energy resources and environmental pollution (L13) Flashcards
What is acid mine drainage
A metal bearing acidic solution formed from the oxidation of sulfides
Acid mine drainage before and after mining
Metal sulfides are stably bound in minerals when they are underground Metals are exposed to the air and they become mobile
Oxidise from sulfides to sulfates
Consequences of Acid Mine Drainage
Sulfuric acid is created as a result
Can oxidise other metal sulfides and/or leach further metals from the surrounding rocks
The acidic waters pick up these dissolved metals and transport them into the nearby rivers
What are the effects of acid mine drainage
The acid waste reduce water pH to below biologically viable limits below 4
At pH values of between 4 and 7, the ferric ions produced in these reactions will tend to precipitate out
Effects of Acid Mine drainage continued
Coats plants and block up stomata
Clogs gills and lungs
Prevents spawning of fish
Treatments of AMD
Active - plantation, 3 stages, sedimentation
Passive - Use of plants to encourage minerals to precipitate out of solution
Heavy metal solubility
More soluble at low pH
High pH means insoluable so will not disperse by water
Enzyme inhibition of metals
Neurotoxins
Symptoms are tingling fingers, slurred speech and reduced coordination
Bioaccumulation of metals
Many are liposoluable
Boimagnification of metals
Many build up in the food chain
Lead has been used for many products such as
Car batteries
Pipes
Solder
Anit-Knock petrol
Lead in industry
Workers may inhale lead dust or absorb it through there skin f it dissolves sweat
Water sprays
Dust masks
Lead in water
Lead pipes
Pipes replaced
Lead in paint
No longer in paint
Paint flakes swallowed
Lead in petrol
Tetraethyl lead (TEL) used to be added to petrol
