Analyzing ventilation requirements and the utilization efficiency of the Kidd Creek mine ventilation system

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Analyzing ventilation requirements and the
utilization efficiency of the Kidd Creek mine
ventilation system
12th North American/U.S. Mine Ventilation
Symposium Reno, Nevada, U.S.A., June 9-11, 2008
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Analyzing ventilation requirements and the
utilization efficiency of the Kidd Creek mine
ventilation system

• Stephen Hardcastle, Charles Kocsis Gary Li,
• CANMET MMSL, Sudbury, Canada
• Kingsley Hortin
• Hatch Associates, Sudbury, Canada
• (Formerly with Xstrata Copper, Kidd Creek,
  Timmins,
• Canada)

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Kidd Creek Mine

• Northern Ontario
• Started as Open Pit in 1966
• Mines 1, 2, 3 now Mine D(Planned to Level
  102 _at_ 3,110m)
• Developed to Level 91 (2,770m)
• gt7,000 tpd copper sulphide from Mines 3 D
• 200 diesel units (gt38,000hp)50 Production units
  (gt14,000hp)

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Kidd VentilationSurface
SVR Exhaust Fan1,300kW (1,750hp)
New NVS Exhaust Fans2 x 2,600kW (3,500hp)
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Kidd VentilationUnderground/Combined

• New Underground Booster Fans,2 x 3,000kW
  (4,000hp) at 60 Level1,800m below surface

• Total Installed Primary System FanMotor Power
  13,600kW (?18,300hp)
• Operational Capacity 1,220m3/s(?2.6Mcfm)

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• Very Significant Operating Cost
• Exhaust Air Plug (_at_7m Ø) wouldwrap around the
  Earth 25x per year

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Ventilation Reviews

• Objective - to reduce cost/improve efficiency
• Initial brainstorming review
• Need to address routing of air to avoidhigh
  resistance fan assisted routes
• SVR system redundant with respect toMines 3 D
• More detailed review needed to assessefficiency
  and the need for increasedventilation management
• 1,500kW (2,000hp) Fan Power removed

X
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Detailed Reviews

• Available Data
• Long-term production plans such as
• a month by month, 18-month schedule of activity
• a year by year, 10 year tonnage plan
• Historical data of daily equipment activity
  recordedby mines personnel
• Design Criteria
• 0.06 m3/s per kW diesel engine power(?100cfm/bhp)

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Generalized Activities

• PRODUCTIONToro 1400 LHD (325hp)
  14.5m3/sShotcrete Hauler (240hp) 10.7m3/s

• DRILLINGCubex Aries ITH (147hp) 6.6m3/sKubota
  M6800 Tractor (68hp) 3.0m3/s

• MISCELLANEOUS14.5m3/s sufficient for standard
  LHD

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Future Requirements

• Iteration 1
• Predictive based upon 18-month plan
• Global 20 allowance for leakage
  non-activelevels
• Extrapolated based upon tonnage
• Minimum flowm3/s

• 1,220m3/s capacity should be sufficient

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Future Requirements

• Iteration 1 Possible Caveats
• Leakage of auxiliary systems ignored
• No allowance to prevent recirculation at
  auxiliaryfans
• 20 allowance to inactive areas/leakage may
  beinsufficient considering number of leaks
• Failing to provide sufficient air to
  non-productiveareas for support activity
• Assumes timely redistribution of airflow
• Experience indicates 2 production LHDs as
  aregular occurrence

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Future Requirements

• Iteration 2
• Predictive 18-month plan extrapolation
• Production ?29m3/s, Drilling ? 14m3/s,Miscellaneo
  us ? 20.7m3/s Non-active ? 3.5m3/s
• System leakage 20
• Minimum flowm3/s, Total includingleakage

• 1,220m3/s capacity remains sufficient
• Still based upon working to an idealized plan

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Past Requirements

• Retrospective based upon production records
• SIMS end of shift data

Work Duration
Shift

• Data exportable to Microsoft Excel

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Past Requirements

• Pivot Table conditional analysis
• Equipment identified and associated
  airflowrequirement allocated to a mining level
  (or levels)
• Assume concurrent activity and sum
  requirementsper level per shift
• Adjust to prevent recirculation at auxiliary
  fani.e. where only a single vehicle operated
• Allot minimum leakage flow sufficient for
  smallservice vehicle (tractor)
• Determine maximum flow needed for each levelper
  averaging period month, week, day

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Past Requirements
Pivot Table month based analysis of 36 Levels

• On average - each level active 316 days/year
  31 of 36 levels active/day
• Flow requirements, 3.5 to 114m3/s, average 27m3/s

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Past Requirements
Pivot Table week based analysis of 36 Levels

• On average - each level active 252 days/year
  25 of 36 levels active/day
• Lower average level airflow requirement of 19m3/s

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Past Requirements
Pivot Table daily based analysis of 36 Levels

• On average - each level active 174 days/year
  17.5 of 36 levels active/day
• Level airflow requirement now averages 11m3/s

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Past Requirements

• Pivot Table Analysis Differences/Caveats
• Potential double accounting same vehicle
  morethan one location this can happen
• Multiple vehicles, up to 5, generate high demands
• Available data provides duration but no
  time-stamp
• Consequently it was not possible to determine
  whether the activity was concurrent or
  sequential
• This backward analysis, based upon observed
  discontinuous activity, highlights maximum demand
• The previous forward analyses were based upon
  idealized continuous averaged activity

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Efficiency/Redundancy

• System Efficiency ? Utilization Efficiency
• An efficient System is one with minimal leakage
  regardless of whether the air distribution is
  appropriate
• Utilization/redundancy is a function of whether
  the distribution meets/exceeds production demands
• All a question of definition
• Todays production air could be tomorrow's
  leakage
• Production demand is that by day, week or month?

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Airflow RequirementsLower Mine Mines 3 D
Monthly average with diesel backfill 1,261m3/s
Mine Delivery Capacity 1,220m3/s
Demand greater than available supply hence
perceived problems
Airflow requirement based upon monthly
distribution with diesel based backfill
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Airflow RequirementsLower Mine Mines 3 D
Monthly average with pastefill 983m3/s
Airflow requirement based upon monthly
distribution with pastefill
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Airflow RequirementsLower Mine Mines 3 D
Weekly average with pastefill 681m3/s
Airflow requirement based upon weekly
distribution with pastefill
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Airflow RequirementsLower Mine Mines 3 D
Daily average with pastefill 400m3/s
Airflow requirement based upon daily distribution
with pastefill
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Airflow RequirementsLower Mine Mines 3 D
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Analysis Findings

• Historical analysis shows the dynamic nature of
  production in a base metal mine constant change
• Hence perceived under performance/inadequacy
• Future plan based requirements are optimistic
• Airflow distribution need to be managed to limit
  total volume of air supplied - significant
  benefits
• More frequent redistribution lowers the
  redundancy - the optimum would be daily
• Redistribution frequency needs to be more often
  than future planning period to operate within the
  design capacity

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Ventilation Management

• Primary system is automated
• Secondary system control is being considered

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Ventilation Management

• Mine introduced more frequent redistribution of
• secondary airflow adjustment of primary system
• Production Engineering schedule upcoming
  activities automatically producing airflow demands

• Ventilation Department reviews requirements and
  produce an action plan
• Operations Group implement changes prior to the
  commencement of the next weeks work activities

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Realized Benefits

• Power Savings from .
• Elimination of a surface fan (initial review)
• Numerous auxiliary fans turned off on inactive
  levels
• Reduced demand/lower operating point for the 2 x
  3000kW boosters
• On average the mine now operates on 930 m3/s
  which is 23 less than delivered at the start of
  the review process

The number of ventilation related complaints has
decreased
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Conclusions

• Base metal mining is never constant
• Ventilation needs vary with changing activity
• Overall demand depends on how often the
  ventilation is adjusted
• Significant differences between operational needs
  if airflows are redistributed daily, weekly or
  monthly
• Long range plans are idealized averages -
  actual operation is different
• Both Forward and Backward analyses have a place -
  both can have limitations
• Ventilation management can save power money -
  it can also be simple

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Acknowledgements Xstrata Copper Kidd Creek
Mine