Research on Value Adding to Minerals in Mongolia

Jadambaa Temuujin Dr.(ScD), Academician of the Mongolian Academy of Sciences

“From Exploration and Exploitation to Development” Value addition to Minerals Industry

Motto of this year:

Typical minerals operation… • discovery of deposit

– resource definition

• mine planning – UG or open pit

• minerals processing – flotation

– gravity

– etc

• chemical extraction – hydrometallurgy

– pyrometallurgy

rock high grade deposits

direct industrial use iron ore, phosphates, limestone etc

concentrate low grade deposits

physically upgraded sulphides, gold etc

metal from concentrate

requires chemical processing high purity

value per tonne

Possible products….

Value adding is the key

ilmenite

synthetic rutile

pigment rutile

Ti metal

%Ti

200

400

2000

20000

US$ / tonne

31.6

~55

60.0

>99.9

Value adding

I. producing purer products

II. producing more sophisticated products

III. decreasing impact on environment

IV. building for the future

Achievements and capabilities of Mongolian minerals researchers

Technology of processing of synchysite

(Ca(Ce,La)(CO3)2F) Preparation of a mixed rare earth oxides

and cerium oxide with 98-99% purity

Fig.5 Technological scheme for preparing mixed rare earth oxides

Ore

(REE 3-8%)

Enrichment

(gravitation)

Synchysite concentrate

(REE 20-28%)

Roasting

(700oC, 120min)

Dissolution

(HNO3 57%, S:L=1:2, 2h)

Non-soluble

remaining

Nitric acid solution of

Rare earth elements

Precipitation of mixed rare earth oxalates by

adding oxalic acid(H2C2O4)

RE2O3

(650oC, 1h)

RE2(C2O4)3

RE(OH)3

(2.5N NaOH)

Synchysite Ca(Ce,La)(CO3)2F is one of only a few rare earth carbonate minerals. It never been considered an economic source of rare earth oxides (REO).

Conventional processing of Molybdenite: -Pyrometallurgical (roasting with soda or lime) -Hydrometallurgical (direct leaching by acid)

Alternative processing: -Very intensive grinding to increase its solubility (however molybdenite is highly stable to mechanical activation because of its layered structure

Processing of molybdenite

Na2O2, kmol

MoS2,

kmol

2MoS2 + 6Na2O2 = 3Na2S + 2Na2MoO4 + Na2SO4

0

30

60

90

120

150

0 2 4 6

Grinding time, h

So

lub

ilit

y, m

g/l

Processing of molybdenite

A new processing method

2. Preparation of MoS2 based solid lubricant with 99% purity

Value added product by natural wolframite

Conventional fabrication process of WC, W+C-blending and calcining at very high temperature, e.g. 1400-2000oC, under

reducing gas, e.g. H2 or CO

FeWO4 + 5C WC + Fe + 4CO

Fe3W3C WC

вольфрамит

50nm

Alternative processing route

Industrial interest

Can we perform value addition of Mongolian minerals at the industrial scale?

Want to say : Yes

Industry has only 1 requirement

Requirements for industry… bulk processing capacity

>5000tpa

minimal energy costs minimisation of grind time (milling energy increases exponentially as the particles get

smaller, the current residence time for size reduction is ~20mins)

advantages over current processes simpler route (less unit operation = lower capex + simpler control)

fewer or less expensive reagents (lower opex)

less environmental impact (less toxic or less unsaleable by-products)

more valuable product (metal or other value added material)

retrofitting equipment can be readily integrated into current flowsheet

What are geopolymers

+ = Fly ash

• Geopolymers are a synthetic inorganic polymer produced by the alkali activation of aluminosilicate raw materials.

• Primarily applied as a replacement for Portland cement • Intrinsically fire resistant

Applications of Geopolymers Applications of geopolymers

Cement replacement Other applications

Most ready

mix applications

Sewerage pipes

Precast panels

Refractory bricks

Fireproof barriers

Mine backfill

Waste containment

Road bases and

marine structures

Ceramic precursor

Aerated wall boards

(thermal insulation)

Applications of geopolymers

Cement replacement Other applications

Most ready

mix applications

Sewerage pipes

Precast panels

Refractory bricks

Fireproof barriers

Mine backfill

Waste containment

Road bases and

marine structures

Ceramic precursor

Aerated wall boards

(thermal insulation)

Mine backfill

Source: M.Drechsler Andrew Graham, Innovative Materials Technologies: Bringing Resource Sustainability to Construction and Mining Industries, 48th Institute of Quarrying Conference, 12-15 October 2005, Adelaide SA

Ongoing and planned projects of thermal power plants

Source: Yeren-Ulzee, www.energy.gov.mn

There will be a plenty of raw materials for the geopolymer application.

Mongolian scientists are ready to cooperate with you

Thank you for the attention!