extracting copper and waste water treatment

what is the first stage of waste water treatment?

• screening

• sedimentation

• filtering

• bacteria digestion

how is the sludge and effluent treated?

• chlorine is added

• UV radiation

• ozone

• bacteria digestion

Effluent and sludge are put into separate tanks. Which one sinks to the bottom?

• effluent

• sludge

Effluent and sludge are separated into different tanks. Which one floats to the top?

• sludge

• effluent

Which tank is sealed and digested with anaerobically (without oxygen)

• sludge

• effluent

What happens to the sludge afterwards?

• chlorine is added to make it safe

• dried out and used as fertiliser

• released back into rivers

High grade ore is

• rock with some metal in it

• rock with enough metal that makes it worth extracting

• rock with crystals in

Economical means

• affluent - rich

• good value for money

• profitable

• worth a lot of money

low grade ore only contains % of metal

• 2%

• 10%

• 30%

• 50%

usually copper is extracted using

• smelting

• electrolysis

• phytomining

• bioleaching