A OPEN PIT MINING AÇIK OCAK MADENCİLİĞİ

23 rd
Figure 1 shows the procedure of the
proposed method.
There are three objectives on the base of
sustainable development concepts:
1. Maximizing social benefit
2. Maximizing economical benefit
3. Minimizing environmental impact
In this paper, a three-objective model is
developed to maximize the economic and
social benefits and minimize the negative
environmental impacts of the selected UPL.
Table 1 gives a summary of the sustainable
development indicators applied for UPL
determination.
Figure 1. The procedure of UPL
determination based on sustainable
development indicators
Table 1. Sustainable development indicators
Environmental
Indicators
Social
Indicators
Economical
Indicators
Reclamation cost
Land use
Stripping ratio (w/o)
Specific energy used
Mine life (year)
Safety
Resource efficiency
Ore content
Profit
ore unit value of the pit
The amount of these parameters
(indicators) is determined for each possible
UPL. Then the rate of these indicators is
calculated for each case according to the
characteristics of each possible UPL. The
rate of each indicator is calculated through
equation 1.
x
ij
x
i ,min
I
ij
(1)
x x
i ,max
i ,min
For those indicators with negative impact,
equation 2 is applied to calculate the rate.
x
i ,max
x
ij
I
ij
(2)
x x
i ,max
i ,min
Where I
ij
is the rate of indicator i for the
pit j, x
ij
, x
i ,max
, and x ,min
is amount of
parameter (indicators) i for the pit j,
maximum amount of indicator i and
minimum indicator i, respectively.
Afterword, considering the principles of
sustainable development, one must
determine the importance and weight of
these indicators ( w
i
in equation 3). This is a
time consuming and case dependant process,
and these weights should be determined
carefully.
Finally, the summation of all the
indicators for each case shows the score of
that particular case (equation 3).
S w x , j indicates each pit (3)
j i i
Where S
j
is the final score of the pit j.
Using the scores, one could determine the
ranking of pits, and select a pit with the
highest score. Next section provides an
example to show the applicability of this
procedure.
2.2 Example
In this section, the procedure described
earlier is applied in an example to show the
effectiveness of this method to determine a
pit limit according to sustainable
development requirements. Consider the
block model given in figure 2.
If the price of the product is 80 units, and
the cost of mining and processing is 4 and 12
respectively, then one could determine the
block economic values and economic block
model (figure 3).
The mathematical model of UPL
determination is given as equations 4-6.
Equation 4 is the objective function and it
tries to maximize the ore content of the pit.
Equations 5 and 6 are constraints of the
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