Lecture 7

Front 1

avg. crustal concentration

Back 1

8.2%

Front 2

U.S. is ?% reliant on bauxite imports

Back 2

100% relient

Front 3

Bauxite ore is converted to ?

Back 3

alumina

Front 4

how much of alumina imported?

Back 4

50%

Front 5

?% of total U.S. alumina is converted to Al meta

Back 5

90%

Front 6

Al is common in ____minerals

Back 6

silicate

Front 7

Al is only produced economically from what kind of mineral group?

Back 7

Hydroxide

Front 8

~__% import reliance for metal

Back 8

26%

Front 9

Al used mostly for

Back 9

transportation, containers, building and construction

Front 10

________deposits are Laterites -
weathering of Al-bearing rocks in
tropical, high-rainfall climates

Back 10

Bauxite deposits

Front 11

Does Al occur often occur with Fe oxide minerals

Back 11

yes.

Front 12

why Al
smelting require industrial
society

Back 12

large electrical power required.

Front 13

Bauxite deposits are
relatively young TF

Back 13

true.

Front 14

Smelting Step 1 (Bayer process):

Back 14

Bauxite is reacted at high temperature and pressure to produce alumina (Al2O3)

Front 15

Smelting Step 2 (Hall process):

Back 15

Alumina dissolves in a molten
bath of the mineral cryolite


Molten Al metal sinks
Tapped into molds for Al ingots


Electrodes are inserted and an electric current is applied
Converts alumina to molten Al meta

Front 16

U.S. production Al has
______ since the 1970’s

Back 16

flattened.

Front 17

Most U.S. Al smelting plants are
near

Back 17

hydropower dams

Front 18

? of US Al production
is from recycled Al scra

Back 18

1/3 of Al production recycled

Front 19

Average crustal concentrations of scarce metals

Back 19

< 0.1 wt. % ( 0.1 g / 100 g)

Front 20

scarce metals

Back 20

   Cr - chromium
Cu - copper
Pb - lead
Zn - zin

Front 21

Large Tonnage, Small concentrations: (scarce metal deposit type)

Back 21

few atoms in common silicate minerals
= low grade

Front 22

Large concentrations, Small Tonnage: (scarce metal deposit type)

Back 22

e: many atoms in uncommon ore minerals
= high grade

Front 23

Mineralogic Gap

Back 23

time between the depletion of high grade ores and
initiation of mining and production from low grade ores
Prices spike during this change

Front 24

The Scarce Metals - Usage

Ferro-alloy metals:

Back 24

Mixed with Fe to make stee;

Front 25

The Scarce Metals - Usage

Base metals:

Back 25

most commonly used scarce metals

Front 26

scarce metal usage
Noble metals (precious metals)

Back 26

don't corrode or rust

Front 27

Ferro-Alloy metals Cr Magmatic Segregation Deposit

Back 27

- layers of dense chromite solidified from a magma
- Several meters thick over

Front 28

Ferro-Alloy metals Chromite FeCr2O4 (45% Cr) -

Back 28

Cr Oxide mineral

Front 29

Ferro-Alloy metals Cr what kind of mining?

Back 29

Underground and Open Pit mining
- blasting and mechanical scrapers

Ore is hand-sorted and concentrated
by density separation

Front 30

Ferro-Alloy metals Chromite (FeCr2O6) is reduced to

Back 30

Ferrochrome

Front 31

Apartheid -

Back 31

Formalized system of racism established in South Africa’s national gov’t
- set up by English and Dutch mine owners and governments in the 1800’s

- sought to subjugate population and control resource wealth
- in place until 1993

Front 32

"kupfernickel"

Back 32

: Old Nick's (devil's) copper (kupfer)
Similar to known copper ores

Front 33

Ferro-Alloy meta Nickle - alloying demand? for?

Back 33

Alloying - 85% of demand
Stainless steel

Front 34

Electroplating -

Back 34

corrosion resistance
high luster polish

Front 35

Ferro-Alloy Ni Magmatic segregation deposits, ?% of mined Ni?

Back 35

70% of mined Ni

Front 36

Sudbury district, Ontario, Canada
2 billion year old Fe/Ni/Cu
meteorite impact

Back 36

Shattered and melted the upper
crust, causing upwelling of mantle
rocks
Ni Sulfide minerals crystallized as
layers

Front 37

Are there Nickle mines in US?

Back 37

Only U.S. Ni mine and smelter closed in the late 1990’s

Front 38

Ferroy Alloy Nickle Strategic mineral to the U.S. (and everyone else) imported from

Back 38

Canada, Russia, Norway, Australia

Front 39

what percent of US consumption of nickle from recycled scrap steel?

Back 39

35% of U.S. consumption supplied by recycled scrap steel
Much of that recovered Ni is re-exported~17% import reliance

Front 40

Ferro Alloy Nickle Residual deposits: Ni-laterites

Back 40

Ni-laterites are surface mined

Front 41

Nickle Sulfide roasted where?
NiO smelted ..?

Back 41

in air
in a furnace with coke.

Front 42

Ferro Alloy Metals -Vanadium and Molybdenum (V&M) good for?

Back 42

important steel alloying elements
Increases the strength and toughness of steel

Lighter weight and/or stronger items “super-alloy’s”
Mo is used in automotive greases to reduce friction and wear

Front 43

what kind of deposits are V&M found?

Back 43

Vanadium is found along with Cr in igneous deposits
with U in deposits concentrated by groundwater dissolution
with organic matter in fossil fuels

Front 44

Ferro Alloy Metals
Environmental Issues

Back 44

Pentlandite - ((Ni,Fe)9S8)
8 tons of Sulfur (S) for
1 ton of Ni metal
released as SO

Front 45

superstack

Back 45

tall smokestack
built to disperse SO2 pollution

Front 46

Chromite mainly in which country?

Back 46

South Africa (Apartheid)