HPGRs in Hard Rock Applications

A Technology Broke Barriers

Egbert Burchardt & Rilmar Ojeda

First Approach of HPGRs to the Copper Industry

metallurgically

considered as a big

success!

widely percepted as a

failure due to

unresolved wear issues!

Cyprus Sierrita

1994 – 1996

POLYCOM 22/13

Growth of HPGRs in Minerals Applications

Diamonds

Iron ore

Hard rock

Latest Trends in Copper / Mineral Ore Processing

traditional SABC circuit

New ore bodies have often been harder and lower grade

=> ultimate need to

to build high capacity concentrators

■ to minimise operating cost

in order to make these projects feasible at all

=> application of the most energy efficient technologies required

in order to mininise energy and consequently wear cost!

Energy requirements of SAG

Mills are about 4 to 16 kWh/t

Freeport – Cerro Verde, Peru

First Copper Concentrator built on HPGR technology

Freeport -

Cerro Verde

Design capacity: 108,000 mtpd

in operation since 2006

(> 120.000 tpd achieveable)

Freeport –

PTFI Grasberg

Freeport – PTFI

Grasberg, Indonesia

First quaternary HPGRs

in a brownfield copper application

Quaternary crushing mode

brownfield installation

Objectives:

1. capacity increase @ same grind

2. higher recovery @ finer grind

2 x POLYCOM 20 / 15

2 x 1,800 kW (each)

Sierrita – quaternary – open circuit

Bagdad – tertiary – closed circuit

Freeport – Sierrita Mine and Bagdad Mine, USA

LOI for largest HPGRs ever built - brownfield copper applications

Testwork for Sierrita Mine

suggested potential to:

reduce BM energy

by up to 22 %

■ increase throughput

by up to 25 %

2 x POLYCOM 26/18

1 x POLYCOM 26/18

2 x 3,300 kW (each)

3,000 – 3,600 tph

(design)

LOI was cancelled in

2008 due to

economical crisis

Freeport –

Sierrita Mine

Bagdad Mine

Anglo Platinum – Mogalakwena North, RSA

First Platinum Concentrator built on HPGR technolgy

Anglo Platinum –

Mogalakwena North

Newmont – Boddington Gold Mine, Australia

First Gold Concentrator built on HPGR Technolgy

96.000 tpd plant

4 x POLYCOM 24/17

2 x 2,800 kW (each)

> 2.100 tph

(design each)

up to 3,000 tph

start-up in 2009

AngloGold Ashanti – Tarkwa Mine, Ghana

First commercial HPGR for heap leaching of gold ore

AngloGold Ashanti –

Tarkwa Mine

In operation since 2009

Freeport –

Cerro Verde

Anglo Platinum –

Mogalakwena North

Freeport –

Grasberg

Newmont –

Boddington Gold Mine

Goldcorp Inc. – Penasquito, Mexico

First HPGR for pebble crushing in a hard rock application

Goldcorp Inc –

Penasquito

Start up in 2010

Operating Plants & Upcoming Installations

Vale –

Salobo Project

Anglo Ferrous –

Minas Rio ProjectBKM – Assmang (2008)

Northam Platinum (2008)

Gindalbie –

Mt. Karara

Moly Mines –

Spinnefex Ridge

Future Trends in Mineral Ore Processing:

Reduction of CO2 emissions to avoid global warming

introduction of CO2 certificates would translate into available power;

available power and required energy translates into maximum capacity

CO2 certificates may limit the capacities of future concentrators

Drastic need to reduce energy consumption even more!

Studies to minimise energy input with HPGRs

More revolutionary concepts may be required!

Future Trends in Mineral Ore Processing

Shortage of water and minimised energy requirements

Could favour

heap leach applications

less energy required

● no wet grinding or wet flotation process required

HPGRs have the potential to elevate the lower recoveries!

■ dry grinding applications

Future Trends in Mineral Ore Processing

Dry HPGR grinding of

hard limestones

BWI up to 16 kWh/mt

320 – 370 tph capacity

Fineness: 80 – 85 % < 90 µm

10.5 to 11.5 kWh/t energy input(HPGR, fan, separator and bucket elavator)

50 % grinding energy required

as compared to ball mill

Future Trends in Mineral Ore Processing

Dry grinding:

saves energy & water,

reduces CO2 emissions!

HPGRs in Hard Rock Comminution

A Technology Broke Barriers

Questions?