WP3: Mine water treatment technologies
Objective
The purpose of the research within WP3 is to investigate highly selective porous adsorptive materials for contaminated mine effluents from selected case study sites in Portugal and Finland. The main aim is to select and test potential adsorptive materials for treatment of As contaminated model (synthetic) and raw mine effluents obtained from field campaigns. The second approach is to investigate advanced ion exchange adsorbent(s) (e.g. based on metal oxides or modified porous media) for removal problematic anions, from process water. The third approach is to use nano particles such as NZVI (Nano Zero Valent Iron) for treating anionic contaminants, which have the advantage of very fast kinetics.
Approach
In this research materials will be tested with model (synthetic) solutions in a laboratory scale experiments. In research, the adsorption/ion exchange removal of arsenic species from water by Fe based material(s) and modified adsorbent(s) will be examined. The batch adsorption experiments will be carried out to determine the baseline process parameters needed for technological applications of selected adsorbents, i.e. uptake kinetics, initial effluent composition, pH, solution temperature, competing-ion effect (e.g. sulphates). As an alternative to synthesis method, in the proposed study, selected porous media (e.g. GAC, recycled materials) will be modified by impregnation/loading with metal oxides. The arsenic removal capacity of the best adsorbent(s) will be verified using raw mining effluent from selected site (within network of cooperating partners).
Depending on time and foreseen applications, pilot plant scale tests will be provided in Finland as outsourcing service from Savonia Applied University and Oulu Water Alliance. The waste materials produced during mine water treatment with adsorbents will be characterized in WP4 and methods for the deposition of waste materials will be evaluated. Additionally, the leachates obtained by these methods can be tested using the direct magneto-electrowinning cell developed for WP2. A comparison set of results will be produced.
- More efficient and economical mine water treatment
- Investigation of advanced adsorbents for As removal
Expected results
Advanced adsorbents developed and tested in this research will improve the mine water treatment and can be used for the better control and treatment of the water related impacts at the mine sites. The experimental results from the breakthrough curves will be used to predict the performance of the adsorption columns operated in continuous flow conditions. Optimal conditions for arsenic removal established on the basis of experiments with model solutions, will be adjusted to conditions and demands given by specific on-site application. Models for prediction of performance will be recalibrated for data obtained for mine waters.
