OPTIMIZATION TECHNIQUES FOR MINING ENGINEERING
CABASAG, TAYAD, VINLUAN
EM508-U1
WHAT IS OPTIMIZATION?
Finding an alternative with the most cost effective or
highest achievable performance under the given
constraints, by maximizing desired factors and
minimizing undesired ones.
COMPONENTS OF OPTIMIZATION
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Objective Function
Decision Variables
Constraints
Step 1: Add the values down each column of blocks.
APPLICATIONS OF OPTIMIZATION IN MINE DESIGN AND
OPERATION:
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Ore-body modelling and Reserve Estimation
The design of optimum pits
The determination of optimal production
schedules
The determination of Operating layouts
The determination of Blends
The determination of Equipment maintenance
and replacement policies
Step 2: From the top block in the left column and working down each column,
put an arrow pointing to the left-adjacent block with the highest bottom value
OPTIMIZATION ALGORITHM
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UG
SURFACE (OPEN PIT)
o Lerchs-Grossmann Algorithm
Lerchs–Grossmann 2D Algorithm
1. The ore model is divided into a series of cross
sections.
2. Each block in the section is assigned a worth
based on the input economics and copper grade
of the block.
3. If the model is high enough, the block would
have a positive worth and would contribute to
the overall worth of that section
4. A block whose grade is below the cut-off grade is
considered waste block. Waste blocks are
assigned a negative value equivalent to the cost
of mining the block.
5. The higher the worth of an ore block, the more
waste blocks can be mined to extract the ore
block.
6. The algorithm develops a pit shape whose limits
represent a breakeven condition.
7. Any material outside the pit slope is not
economic at the input parameters used.
Step 3: Trace the arrows back to get the outline of the pit starting from the
top row block with the maximum total value.