"Modelling of Multiphase Multicomponent Flow and Transport in Heap Leaching of Copper Ores"
PDF-VersionThe configuration considered in this master thesis consists of a ore heap that is
irrigated on top with a dilute solution of sulfuric acid. As the solution permeates
through the ore material it dissolves the minerals (the copper ions). In this way the
copper is leached out of the ore and can be separated later on from the leaching
solution and be further processed. Two phenomenas of interest in this work are the
multiphase flow problem through the ore heap and the physico-chemical reactions.
The reactions of the acid leaching solution with the copper will be simulated as
a desorption problem from the ore into the solution. The mass transfer of the copper
into the solution is in our case not dependend on the acid concentration. Furthermore
the acid concentration does not deplete due to the leaching process.
The following steps have been taken:
-Simulation of flow through the heap by a 2 Phase flow model in 2 dimensions. Necessary steps included grid construction, definition of boundary conditions, definition of parameter settings like irrigation rate etc.
-Simulation of 2 phase 3 component flow through the heap by an extendet model setup. Components in the liquid phase include copper, sulfuric acid and air.
- A sensitivity study was conducted. The parameters under investigation were e.g. the Brooks-Corey or vanGenuchten constants in the capillary pressure - saturation relationship, irrigation rate, absolute permeability, relative permeability, desorption coverning parameters etc.
- A more complex, layered configuration of the heap has been modelled. This is more realistic since the permeability, porosity etc. varies over depth of the heap.