How is the service life of the mine determined?
After years of practice, the service life of the mine should be determined on the basis of economic rationality, as shown in Table 1.
Table 1 Reasonable service years of different types of mines
Mine type | Annual output of ore (10,000 tons) | Mine service life (a) | |
Ferrous metals | Non-ferrous metal | ||
Large | More than 100 | More than 100 | 30 or more |
Medium | 30~100 | 20~100 | 20 or more |
Small | 30 or less | 20 or less | 10 to 15 or more |
When the deposit is fixed, the annual relationship, the service life of the mine and the deposit Q of the mine have the following relationship:
A=(Q/t 1 )[P/(1-Ï)]
Where A-year production, t/a;
Q-mineral reserves, t;
P-ore recovery rate, %;
æ··-waste stone mixing rate, %;
t 1 - Calculates the service life.
The calculation service life of the mine does not take into account the fact that production at the beginning and end of production does not reach normal production capacity. Therefore, the actual service life of the mine is always longer than the calculated service life t 1 , and the growth time is generally 1 to 5 a.
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