Palabora Block Cave Mine – a world class benchmark … Pretorius.pdf · Why Block Cave Mining? U/G mining method ... • By undercutting an area ... • Two major drivers of the

Palabora Mining Company Limited

Palabora Block Cave Mine – a world class benchmark design

Dawid Pretorius, General

Manager Mining, Palabora

Mining Company, South Africa

Mine-Tech International Conference and Expo, 2-4 November 2009, Johannesburg, South Africa

Background

Palabora Ore body forms part of the

Palabora Igneous complex formed

by a series of volcanic eruptions.

The Ore Body contains a unique

variety of minerals - copper,

Phosphates, magnetite, uranium,

zirconium, nickel, gold, silver,

platinum, and palladium.


Background cont.

1965: Commissioning of Palabora Open pit Mine


Background cont.

1996: Faced with decision to close in 2002 or to go underground.

Rio Tinto decided to start the block cave mine.


Why Block Cave Mining?U/G mining method

• Suitable for massive orebodies which have a large, regular “footprint” and either dip steeply or are of a large vertical extent.

• By undercutting an area equivalent to the HR, caving is initiated.

• Two major drivers of the caving process are:

• Gravity

• Stresses

• Low OPEX but HIGH CAPEX

Extraction

Level

Draw Bell

Undercut


Block Cave Mining


Technical Challenges

•Greatest column height in the world

•Hardest rock for a block cave

•Coarsest fragmentation for a block cave

•Lowest grade underground copper mine in the world @ 0.7% Cu


Equipment

•17 LHD (Load Haul and Dump) with 2 OEM’s – Caterpillar and Sandvik

•4 Mobile Rock breakers

•5 Water Canons

•Ancillary vehicles

•4 Medium Reach Rigs

•Production Shaft: 2 Cope Winders with 4*32 Ton skips

•Service Shaft: 30 Ton Cage and a Mary Anne


Technology

PDS (Pedestrian Detection System)

•Dispatch (MMSA)- Fleet and Information Management System

•Gemcom Software (PCBC & CMS)

•Rebop and Arena (Simulation)

•SCADA for Fixed Plant enabling Conditional Monitoring

•Planning (Prima Vera and SAP)


Management Principles

•Theory of Constraints •Rock Factory – managing value chain

•Planning based on bottleneck requirements

•Planning approach

•Do not skip any maintenance

•Draw Control

•Visible felt Leadership (Safety)


Achievements

•Safety – One of the Safest underground mines in South Africa AIFR = 0.42

•85% Planned vs. 15% unplanned maintenance on all fixed and mobile plant

•Production: 34,000 tons vs. 30,000 design capacity – Highest volume single shaft in the world


Achievements

•Best Day 42,998 tons May 2005

•Best Week 37,247 tons Week 22 2008

•Best Month 35,993 tons August 2008


Future Rio Tinto Block Caves

0.1

1

10

100

0 5 10 15 20 25 30 35 40Contained Equ iv. Copper mineralisation - Mt

Cop

per E

quiv

. Gra

de -

% C

u

Oyu Tolgoi

Pebble

Resolut ion

La Granja

Note: bubble siz e reflects total annual capacity

CompetitorsRT Projec ts


Where to from here?

•Low grade ore bodies

•Extension for open pit mines

•Mine of the future – remote and autonomous operation possibilities

•21st Century mining is here to stay


Questions?

Thank You

Documents

Palabora Block Cave Mine – a world class benchmark … Pretorius.pdf · Why Block Cave Mining? U/G mining method ... • By undercutting an area ... • Two major drivers of the