During the biosobent work package of Min-North project the suitability of applying peat and sawdust for the purification of mining wastewater (removal of select metals and nitrogen) is evaluated. The research was divided into two phases: 1) Batch tests laboratory studies and 2) Pilot studies.
Mining area drainage water was used for all tests. During phase 1, natural and chemically (HCl) treated peat as well as chemically treated (CHMAC) sawdust materials were accessed for their metal and nitrogen removal capacity. Peat was tested for the removal of positive ions (metals) and saw dust for the removal of negative ions (focus on nitrate removal). The modified sawdust material did not perform well in the removal of nitrogen species or other anions such as sulphate even at high doses. Generally, natural peat showed higher metal reduction capacity compared to modified peat. The effect of contact time, dosage and temperature was also less pronounced on natural peat performance than HCl treated peat performance. Sorbents were fully characterized before and after chemical treatment and before and after their utilization (XPS, FTIR). Complete results will be presented (oral presentation) during the 13th International Mine Water Association Congress, Lappeenranta, Finland (June, 2017). http://www.imwa2017.info/
Gogoi, H., Leiviskä, T., Heiderscheidt, E., Postila, H., Tanskanen, J., 2017. Removal of Metals from Mining Wastewaters by Utilization of Natural and Modified Peat as Sorbent Materials.
During phase 2, the two best performing sorbents in phase 1 (natural and chemically treated peat) were evaluated in pilot scale tests of two water treatment systems; mix and settling and horizontal filter system. Results of pilot experiments are still being analyzed. Preliminary results of the horizontal filter system will be presented (poster) during the 13th International Mine Water Association Congress, Lappeenranta, Finland (June, 2017). Full manuscript including both pilots to be submitted at the end of 2017.
Heiderscheidt, E., Postila, H., Ronkanen, A-K., Campos Lopez, F., Gogoi, H., Leiviskä, T. Pilot Scale Evaluation of the Suitability of Peat as Sorbent Filter Material for Metal Removal from Mining Drainage Water.
Results will also be presented during the joint Min-North and RESEM project seminar to occur towards the end of September 2017 in Oulu, Finland. Further details will be posted soon!
Last updated: 19.5.2017