Lecture 9 Flashcards
What are the three types of mining
Open pit
Underground
In-situ leaching
Describe when open pit mining is appropriate and give one positive and negative
When the minerals lie close to the surface
When the deposits have a large lateral extent
+ve It is faster than other methods
-ve Large amounts of spoil/tailings produced
What are the four types of underground mining
Cut and fill
Stope and pillar
Jet boring
Raise boring
How does in-situ leaching work
A leaching solution is pumped into the rock through drilled holes, it dissolves the Uranium forming a Uranium rich solution, this is then pumped back to the surface and the Uranium is seperated back out of solution
What form of Uranium is soluble and what is its oxidation state
Uranyl (+6)
How would you identify Uranyl
It is brightly coloured (red, orange, yellow and green)
What form of Uranium is not soluble and what is the oxidation state
Uranous (+4)
How to recognise Uranous
Dull coloured (brown or black)
What kind of environments are Uranyl and Uranous formed in
Uranyl - oxidising
Uranous - reducing
What are the three common types of Uranium ore deposit
Hydrothermal
Unconformity
Vein-type
What is ore milling
refining the raw material into a usable product
What makes ore milling of Uranium different to other minerals
It is redioactive and dangerous
Why is crushing and grinding a key step in the refining process
To make the ore smaller and more easily leached
What is Preconcentration (Beneficiation)
The seperation of U-bearing minerals from the gangue minerals
What is the purpose of Preconcentration (Beneficiation)
Enhances the feed grades for subsequent treatment
Removes minerals that are likely to hinger Uranium leaching or recovery
Provide clean tailing that can be rejected without causing environmental concerns
