Pyrite-rich tailings oxidation ina a bench scale reactor

Abstract

The mining industry is a relevant economical activity in Mexico. However, it is also one of the industries
that generate more wastes. Tailings (“jales” in Spanish from the aztec term “xalli”, fine sands) figure among
them. Mexican standards define tailings as “solid wastes generated in the primary operations of separation
and concentration of minerals” and tailings pond or dam, the deposits where they are disposed of, as
“engineering constructions for the storage and final disposal of the tailings, which are built and operated
simultaneously”. In the present study, essays to simulate the filling of a tailings pond or dam were performed.
The follow up parameters used where taken from a previous study in which it was found that long periods of
drought followed by strong precipitations, favor the oxidation of the pyrite in the tailings. The objective of
the present research was to determine the effect of these conditions in the leachates characteristics that could
be generated. During the tests, the maximum allowed limits for metals stated in Mexican standards where not
exceeded and the values of pH and iron concentration were similar to the data analyzed from the tailings pond
water samples and the humidity cell tests.