Mineral barrier systems for the treatment of metal-polluted water from an alum shale deposit
Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
Oil and gas were recovered from alum shale (black shale) at Kvarntorp, Närke,during a period of 24 years. One of the remnants of this industry is a 100 m highdeposit with high contents of uranium, arsenic, molybdenum, vanadium and otherelements. Presently the leakage of metals from the deposit into nearby streams israther modest but will most likely accelerate in the near future. One way to preventan uncontrolled leakage of these elements from the deposit into the environmentwould be to install a filter with an effective adsorbent that after saturation could easilybe regenerated and reused. The filter could not only be used to reduce the impact ofmetal leakage to the environment but also to reclaim valuable elements like nickel,vanadium, uranium and molybdenum. Unfortunately such a filter does not existtoday, but there are a wide range of minerals that have high adsorbing capacities andcould serve as filter components in a mineral barrier system. The adsorbingproperties of some natural minerals with respect to selected metals that are abundantin the Kvarntorp deposit are studied in this project. These minerals are bentoniteclay, (burnt clay), unburnt shale (stybb), burnt shale (rödfyr), apatite, peat andbark. In the experiments each sorbent was blended with artificial groundwater and acertain amount of metal stock solution. Samples were taken at five different pH.The results show that the two shale-products stand out from the othersand have the best adsorbing qualities for nickel, copper and zinc. At a pH over 7between 96 and 99% of the metal ions were removed from the solution.Unburned shale especially shows remarkably good results for vanadiumthroughout the tested pH range of 3,4-7,7 between 98 and 99% of the vanadium ionswere removed from the solution. Unburned shale performs best of the testedadsorbents and could probably be used as an adsorbent in a geological barrier butmore research is needed.
Place, publisher, year, edition, pages
2014. , 43 p.
Examensarbete vid Institutionen för geovetenskaper, ISSN 1650-6553
, Självständigt arbete, 102
Oceanography, Hydrology, Water Resources Chemical Sciences Environmental Sciences
IdentifiersURN: urn:nbn:se:uu:diva-227452OAI: oai:DiVA.org:uu-227452DiVA: diva2:734891
Bachelor Programme in Earth Science
2014-06-03, Hambergsalen, Institutionen för geovetenskaper, Uppsala universitet, Villavägen 16, Uppsala, 10:10 (Swedish)
Herbert, Roger, DocentAllard, BertKarlsson, StefanSjöberg, Viktor
Hellqvist, Magnus, Universitetslektor