mine plan case study
DESCRIPTION
Mine Plan Case StudyTRANSCRIPT
Introduction
Ventilation in mine Ventilation in mine design processdesign processo FeasibilityFeasibilityo Design changesDesign changeso Quantify amount of air Quantify amount of air
requiredrequired Impact of larger mobile Impact of larger mobile
equipment fleetequipment fleeto Auxiliary circuitAuxiliary circuito Main ventilation circuitMain ventilation circuit
Secondary EgressSecondary Egresso Impacts shaft Impacts shaft
design design Implementation Implementation
o staged staged implementationimplementation
ConclusionsConclusions
Lisheen’s Vital Statistics
Cool, wet climate 352 Employees from
14 countries Underground Zinc
and Lead Mine High grade Mine life 1999 - 2014 1.6 million tonne
annual production rate
Strict Environmental Conditions
Bog Zone
The Bog Zone is a new addition to the The Bog Zone is a new addition to the Lisheen Mine which extends the Lisheen Mine which extends the underground footprint eastwards.underground footprint eastwards.
The feasibility study completed in 2003 The feasibility study completed in 2003
Planning permission received from North Planning permission received from North Tipperary County Council a year later.Tipperary County Council a year later.
Developed from 2004-2007Developed from 2004-2007
Provides 43% of future metal for LisheenProvides 43% of future metal for Lisheen
Mine Planning & Ventilation – Feasibility Stage 2003
N
Bog West
Bog East
VR6
VR7 VR8
Bog CentralScale100m
haulage
Lisheen Property Boundary
Mine Planning & Ventilation - Bog Zone Mine Design Change 2006
Mining MethodMining Method mm33/s//s/MtpaMtpa
Large open stopes Large open stopes >0.5 Mtpa>0.5 Mtpa
160160
Small open stopes Small open stopes <0.5 Mtpa<0.5 Mtpa
240240
Room and PillarRoom and Pillar 200200 N
Bog West
Bog Central
Bog Easthaulage
VR7 VR8
VR6
Scale100m
New Auxiliary Fan Sizes 2007
Lisheen standard 0.04 m³/s per kW of Lisheen standard 0.04 m³/s per kW of rated engine powerrated engine power
Average heading requires 24 m³/s Average heading requires 24 m³/s o based on a 250 kW loader and a 40 based on a 250 kW loader and a 40
tonne (350 kW) trucktonne (350 kW) trucko standard auxiliary fans employed meet standard auxiliary fans employed meet
this requirementthis requirement Loading 50 tonne (450 kW) trucks with Loading 50 tonne (450 kW) trucks with
350 kW loaders350 kW loaderso target delivery airflow of 34 m³/starget delivery airflow of 34 m³/s
Larger auxiliary fans requiredLarger auxiliary fans required
Reevaluate Total Volume Flow
New standard for the Bog Zone auxiliary fansNew standard for the Bog Zone auxiliary fans
Determine the overall amount of air needed Determine the overall amount of air needed based on:based on:o the total number of working headings in Bog the total number of working headings in Bog
Zone Zone o the size of the fleet and crewthe size of the fleet and crewo the overall mining schedulethe overall mining scheduleo increase amount of air on haulageincrease amount of air on haulage
Amount of air needed is 200mAmount of air needed is 200m33/s/s
40% increase of total airflow required to mine 40% increase of total airflow required to mine Bog ZoneBog Zone
OMG! 40% More Air Required!!
VR6 and VR7 have been raiseboredoContractor to
return in four months to complete VR8
Lisheen does not have a current ventilation modeloConsultant hired
to perform model simulations
External Review and Modeling
VR8 escapewayVR8 escapeway Planned 3m Planned 3m
diameterdiameter 100 m100 m33/s and /s and
ladderwayladderway Revise plan to 4m Revise plan to 4m
diameterdiameter
External Review and Modeling
BZ haulage airflow directionBZ haulage airflow direction Total volume through VR7Total volume through VR7 Operating CostOperating Cost
o minimize electrical powerminimize electrical power cost – US $1.1 million/yrcost – US $1.1 million/yr capped by electrical gridcapped by electrical grid
N
Bog West
Bog Central
Bog Easthaulage
VR7 VR8
VR6
Scale100m
Jet-thrust
Staged Implementation
In-house waste development - November 2004In-house waste development - November 2004 Auxiliary force ventilationAuxiliary force ventilation In house waste development 50m a monthIn house waste development 50m a month
o Bog Zone full production by September 2007Bog Zone full production by September 2007
Scale100mN
Aux. force fan
Aux. exhaust fan
Staged Implementation – Accelerated Development
Contractor start development August 2006 November 2006 Raiseboring of VR6 complete Auxiliary vent move up
Scale100m
N
VR6
Staged Implementation – Accelerated Development
Underground access VR7 complete February 2007
April 2007 raiseboring VR7 finished Auxiliary vent move up
o In-line booster fan
Scale100mN
VR7
VR6
In-line booster fan
Staged Implementation – Accelerated Development
Underground access VR8 complete July 2007 Raiseboring VR8 finished September 2007 Raiseboring VR7A complete October 2007
VR6
VR7
Scale100mN
VR8VR7A
Staged Implementation – Main Fan
QuotationQuotation Operating CostOperating Cost
o minimize electrical powerminimize electrical power cost – a single kW US $1400/ yrcost – a single kW US $1400/ yr capped by electrical gridcapped by electrical grid
Procurement IssuesProcurement Issues Installation planned August 2008Installation planned August 2008
Staged Implementation – Secondary Egress
Cost benefit analysis of ladderway vs refurbished Alimak
December 2007 VR8 supported
Refurbished Alimak to be installed end of this month
Conclusions
Ventilation plans must be reevaluated and Ventilation plans must be reevaluated and changed as conditions evolve. changed as conditions evolve. o realize a better distribution of airflow, realize a better distribution of airflow,
optimized secondary escape way, reduced optimized secondary escape way, reduced contaminants, and reduced total power contaminants, and reduced total power requirements. requirements.
Supply chain problems can greatly affect Supply chain problems can greatly affect timeline.timeline.
Computerized ventilation modeling and Computerized ventilation modeling and planning for staged implementation should planning for staged implementation should never be underestimated. never be underestimated.