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Karlsson, Stefan
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Allard, B., Sjöberg, S., Sjöberg, V., Skogby, H. & Karlsson, S. (2023). Metal Exchangeability in the REE-Enriched Biogenic Mn Oxide Birnessite from Ytterby, Sweden. Minerals, 13(8), Article ID 1023.
Öppna denna publikation i ny flik eller fönster >>Metal Exchangeability in the REE-Enriched Biogenic Mn Oxide Birnessite from Ytterby, Sweden
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2023 (Engelska)Ingår i: Minerals, E-ISSN 2075-163X, Vol. 13, nr 8, artikel-id 1023Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

A black substance exuding from fractures was observed in 2012 in Ytterby mine, Sweden, and identified in 2017 as birnessite with the composition Mx[Mn(III,IV)](2)O-4 center dot(H2O)n. M is usually calcium and sodium, with x around 0.5. The Ytterby birnessite is unique, with M being calcium, magnesium, and also rare earth elements (REEs) constituting up to 2% of the total metal content. The biogenic origin of the birnessite was established in 2018. Analysis of the microbial processes leading to the birnessite formation and the REE enrichment has continued since then. The process is fast and dynamic, as indicated by the depletion of manganese and of REE and other metals in the fracture water during the passage over the precipitation zone in the mine tunnel. Studies of the exchangeability of metals in the structure are the main objective of the present program. Exposure to solutions of sodium, calcium, lanthanum, and iron led to exchanges and altered distribution of the metals in the birnessite, however, generating phases with almost identical structures after the exchanges, and no new mineral phases were detected. Exchangeability was more efficient for trivalent elements (REE) over divalent (calcium) and monovalent (sodium) elements of a similar size (ionic radii 90-100 pm).

Ort, förlag, år, upplaga, sidor
MDPI, 2023
Nyckelord
Ytterby mine, biogenic Mn mineralization, birnessite, rare earth elements enrichment
Nationell ämneskategori
Geokemi
Identifikatorer
urn:nbn:se:oru:diva-108411 (URN)10.3390/min13081023 (DOI)001055746500001 ()2-s2.0-85168870545 (Scopus ID)
Tillgänglig från: 2023-09-27 Skapad: 2023-09-27 Senast uppdaterad: 2024-01-17Bibliografiskt granskad
Nilsson, C., Sjöberg, V., Grandin, A., Karlsson, S., Allard, B. & von Kronhelm, T. (2022). Phosphorus speciation in sewage sludge from three municipal wastewater treatment plants in Sweden and their ashes after incineration. Waste Management & Research, 40(8), 1267-1276, Article ID 734242X211065231.
Öppna denna publikation i ny flik eller fönster >>Phosphorus speciation in sewage sludge from three municipal wastewater treatment plants in Sweden and their ashes after incineration
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2022 (Engelska)Ingår i: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 40, nr 8, s. 1267-1276, artikel-id 734242X211065231Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Given the high efficiency in phosphorus removal at municipal wastewater treatment plants (MMWWTP), sewage sludge constitutes a promising resource for phosphorus (P) recovery. Sewage sludge is, however, a complex matrix and its direct use as fertiliser is limited by its content of metals/metalloids and organic pollutants. In order to increase its usability as a potential resource of P, there is a need for increased knowledge on phosphorus speciation in these matrices. The sludge composition is highly influenced by local conditions (i.e. wastewater composition and treatment method), and it is therefore important to study sludge from several MMWWTPs. In this study, three different protocols for sequential extraction were utilised to investigate the chemical speciation of phosphorus in sludge from three different MMWWTP sludges in Sweden, as well as in corresponding ashes following incineration. The results showed that the total amounts of phosphorus ranged from 26 to 32 mg g-1 sludge (dry weight), of which 79-94% was inorganically bound (IP). In the sludge, 21-30% of the IP was associated with calcium (Ca-P), which is the preferred species for fertiliser production. Following incineration, this fraction increased to 54-56%, mainly due to transformation of iron-associated phosphorus (Fe-P), while aluminium-associated species of phosphorus (Al-P) remained unaltered. The results from this study confirm that incineration is a suitable treatment for sewage sludge in terms of potential phosphorus recovery.

Ort, förlag, år, upplaga, sidor
Sage Publications, 2022
Nyckelord
Sewage sludge, bioavailability, incineration, phosphorus, recirculation, speciation, sustainability, wastewater
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:oru:diva-96079 (URN)10.1177/0734242X211065231 (DOI)000736222100001 ()34920692 (PubMedID)2-s2.0-85121694485 (Scopus ID)
Anmärkning

Funding agency:

Norrtorp Kumla Environmental foundation

Tillgänglig från: 2021-12-21 Skapad: 2021-12-21 Senast uppdaterad: 2022-09-12Bibliografiskt granskad
Liem-Nguyen, V., Sjöberg, V., Dinh, N. P., Huy, D. H. & Karlsson, S. (2020). Removal mechanism of arsenic (V) by stainless steel slags obtained from scrap metal recycling. Journal of Environmental Chemical Engineering, 8(4), Article ID 103833.
Öppna denna publikation i ny flik eller fönster >>Removal mechanism of arsenic (V) by stainless steel slags obtained from scrap metal recycling
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2020 (Engelska)Ingår i: Journal of Environmental Chemical Engineering, E-ISSN 2213-3437, Vol. 8, nr 4, artikel-id 103833Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

With this study, the removal mechanisms of arsenate by steel slag and its potential for treatment of contaminated water were elucidated. While original slag showed a poor fit to the Langmuir equation (R2 = 0.960), washed slag (the original slag is washed by low pH water solutions to remove readily soluble oxides) conformed better (R2 = 0.995). An initial pH of 2.0 give optimal adsorption, with a strong impact from the chemical speciation observed with highest efficiency for the fully protonated (OH)3AsO form. Adsorption capacity of the slag is 4.0 mg g−1, while together with precipitation the retention capacity reaches 13.7 mg g−1. However, removal by precipitation is a non-steady process due to re-dissolution of Ca3(AsO4)2(s). The washed slag shows a similar adsorption capacity to the original one but has not as strong alkaline properties. Batch experiment shows fast adsorption kinetics and column loading tests indicate an instant adsorption kinetics with 80 % As(V) removal for a 10 mg L−1 As(V) solution by 1.0 g of washed slag using a solution flowrate of 1 mL min−1. Common ions like sulfate, carbonate, chloride, iron(III), humic acid and fulvic acid do not significantly interfere with the removal efficiency. In combination with limited hazardous metals leaching, the slag is thus appropriate for use as a filter material for treatment of contaminated water and it has been successfully applied as filter material for treatment of arsenate spiked natural water sample with average removal efficiency of 84 % (solid to liquid ratio of 200).

Ort, förlag, år, upplaga, sidor
Elsevier, 2020
Nyckelord
Arsenic, Steel slag, Contaminated waters, Precipitation, Adsorption
Nationell ämneskategori
Miljövetenskap
Identifikatorer
urn:nbn:se:oru:diva-84680 (URN)10.1016/j.jece.2020.103833 (DOI)000563932900004 ()2-s2.0-85086509805 (Scopus ID)
Anmärkning

Funding Agencies:

MINRENT project (Vinnova, Swedens innovation agency)  2016-02830

EnForce profile (KKS, The Knowledge Foundation)  20160019

Faculty of Business, Science and Engineering at Örebro University  

Tillgänglig från: 2020-08-11 Skapad: 2020-08-11 Senast uppdaterad: 2023-12-08Bibliografiskt granskad
Rai, N., Sjöberg, V., Forsberg, G., Karlsson, S., Olsson, P.-E. & Jass, J. (2019). Metal contaminated soil leachates from an art glass factory elicit stress response, alter fatty acid metabolism and reduce lifespan in Caenorhabditis elegans. Science of the Total Environment, 651, 2218-2227
Öppna denna publikation i ny flik eller fönster >>Metal contaminated soil leachates from an art glass factory elicit stress response, alter fatty acid metabolism and reduce lifespan in Caenorhabditis elegans
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2019 (Engelska)Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 651, s. 2218-2227Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

The present study evaluated the toxicity of metal contamination in soils from an art glass factory in Smaland Sweden using a Caenorhabditis elegans nematode model. The aim of the study was to chemically analyze the soil samples and study the biological effects of water-soluble leachates on the nematodes using different physiological endpoints. The total metal content showed that As, Cd and Pb were at levels above the guideline values for soils in areas around the factory. Less than 10% of the total metal content in the soil was found in the water-soluble leachates, however, Al, As, Fe and Pb remained higher than the guideline values for safe drinking water. Exposure of C. elegans to the water-soluble leachates, at both post-hatching larvae stage (L1-young adult) for 48 h and at the young adult stage (L4) for 6 h, showed significant gene alteration. Although the nematodes did not exhibit acute lethality, lifespan was significantly reduced upon exposure. C. elegans also showed altered gene expression associated with stress response and fat metabolism, as well as enhanced accumulation of body fat. The study highlighted the significance of assessing environmental samples using a combination of gene expression analysis, fatty acid metabolism and lifespan for providing valuable insight into the negative impact of metals. The altered fat metabolism and reduced lifespan on exposure to soil leachates motivates further studies to explore the mechanism of the toxicity associated with the metals present in the environment.

Ort, förlag, år, upplaga, sidor
Elsevier, 2019
Nyckelord
Contaminated soil, Water-soluble leachates, Ecotoxicology, Lipid metabolism, Heavy metals, Glass manufacturing
Nationell ämneskategori
Miljövetenskap
Identifikatorer
urn:nbn:se:oru:diva-70482 (URN)10.1016/j.scitotenv.2018.10.067 (DOI)000450551600055 ()30326454 (PubMedID)2-s2.0-85054622934 (Scopus ID)
Forskningsfinansiär
KK-stiftelsen, 20150084
Tillgänglig från: 2018-12-05 Skapad: 2018-12-05 Senast uppdaterad: 2018-12-05Bibliografiskt granskad
Sjöberg, V. & Karlsson, S. (2017). LC-MP AES as a screening tool for metal-DOC interactions in ARD. In: Bio-geo interactions: basic knowledge to application: 16th Symposium on remediation in Jena “Jenaer Sanierungskolloquium”. Conference proceedings. Paper presented at 16th Symposium on remediation, Jena, Germany, October 5-6, 2017 (pp. 43-43).
Öppna denna publikation i ny flik eller fönster >>LC-MP AES as a screening tool for metal-DOC interactions in ARD
2017 (Engelska)Ingår i: Bio-geo interactions: basic knowledge to application: 16th Symposium on remediation in Jena “Jenaer Sanierungskolloquium”. Conference proceedings, 2017, s. 43-43Konferensbidrag, Poster (med eller utan abstract) (Övrigt vetenskapligt)
Abstract [en]

Dissolved organic carbon (DOC) such as humic and fulvic acids have a high ability to form stable complexes with many metal ions. Also otherwise insoluble elements may be mobilized by complexolysis. Detection of the humic substances can be made with size exclusion chromatography (SEC) with UV/Vis and fluorescence detection. To detect the metals that different organic compounds carry the metal content in the eluent can be analyzed. However, the phosphate buffer that is used in the reference method is not well suited since phosphate and hydrogen phosphate ions are excellent complexing agents for many metals. In this work ammonium nitrate buffer was evaluated and used.

To decrease the analytical cost and streamline the analytical procedure an LC-system (Agilent 1260) was connected to an MP AES (Agilent 4200). After separation and spectroscopic measurements the eluent was lead to the nebulizer and the metal content in the eluent was determined as a function of time.

When acidic shale residues come in contact with wood chips, acidic hydrolysis and microbial degradation generate a complex mixture of hydrophilic organic compounds and acid rock drainage (ARD). If no subsequent condensation occurs the released organics would mainly contain low molecular weight carbon compounds (LMWOC). The fluorescence at 443 nm after exitation at 345 nm reveals that compounds of humic and fulvic character are present in the leachates. The content of manganese in the more complex forms of organic compounds is limited and it is mainly associated with LMWOC. Hence, humic compounds are not a good carrier of manganese in this type of system.

By using ammonium nitrate as buffer solution the separation was almost identical to the phosphate buffer. The results show that LC and MP AES can be used for analysis of the metal content as a function of size of organic carriers, such as humic substances and LMWOC. By using MP AES for metal analysis, operating cost is significantly decreased compared to hitherto used methods based on ICP. The results also indicate that substances with humic character form during acidic and microbial degradation of wood. From an environmental perspective this is of importance since several organic compounds facilitate metal mobilization.

Nationell ämneskategori
Miljövetenskap
Identifikatorer
urn:nbn:se:oru:diva-64736 (URN)
Konferens
16th Symposium on remediation, Jena, Germany, October 5-6, 2017
Tillgänglig från: 2018-01-31 Skapad: 2018-01-31 Senast uppdaterad: 2022-09-28Bibliografiskt granskad
Karlsson, S., Sjöberg, V. & Allard, B. (2017). Metal transport dynamics in a small watershed - Dylta bruk, Sweden. In: Bio-geo interactions: basic knowledge to application: 16th Symposium on remediation in Jena “Jenaer Sanierungskolloquium”. Conference proceedings. Paper presented at 16th Symposium on remediation, Jena, Germany, October 5-6, 2017 (pp. 23-23).
Öppna denna publikation i ny flik eller fönster >>Metal transport dynamics in a small watershed - Dylta bruk, Sweden
2017 (Engelska)Ingår i: Bio-geo interactions: basic knowledge to application: 16th Symposium on remediation in Jena “Jenaer Sanierungskolloquium”. Conference proceedings, 2017, s. 23-23Konferensbidrag, Muntlig presentation med publicerat abstract (Övrigt vetenskapligt)
Abstract [en]

Metal transport in small streams in boreal catchments is a function of weathering rate, water balance and redistribution mechanisms. Because of these highly dynamic processes long term water quality changes are difficult to determine but needed in order to assess the impact of several local and largescale changes on local water quality.

The field site is situated at Dyltabruk, some 20 km North of Örebro in South Central Sweden. The 4 km2 catchment has deciduous and coniferous species on a granitic moraine with some 20% ofmires and fens adjacent to the oldest sulphur mine in Sweden. Grab samples were collected weekly since 2006 but more frequent during periods with large changes in water balance. The samples were analysed for general hydrochemical parameters (temperature, electrical conductivity, pH, dissolved organic carbon (DOC), inorganic carbon (IC), fulvic and humic acids and dissolved oxygen), dissolved principal anions, principal and trace metals. Standardized analytical procedures were applied. Temperature, precipitation and other climatic parameters were recorded some 2 km from thesite every 15 minutes.

The results showed a general concentration pattern where the water balance had the largest single influence. The concentrations had a seasonality inversely related to the ground water level. Inter annual variations of one to two orders of magnitude were observed for group 1 and 2 elements. For transition metals with high affinity to solid matter as well as DOC the variation reached three to four orders of magnitude. Only aluminium and iron had concentrations that occasionally exceeded solubility limits which resulted in a similar inter annual variation.

During the study period the average annual temperature and precipitation were no different (p 0.05) from the previous ten years but rainfall intensities increased. In a long term perspective the concentrations for all metals except calcium had positive trends. The tendencies remained when normalizing against chloride. The same was found for DOC, nitrate and sulphate. Hence, there is an accelerating loss of most elements that is not limited by weathering. It is uncertain, however, if the positive trends for DOC depend on increased production or a balancing release from the supply in mires and fens. In addition, there is also an indication of increasing inter annual concentration changescwith time. Although not exclusively proven such phenome would occur as a result of increased rainfall intensity. It is therefore likely that the accelerating loss of elements is a result of increased weathering rather than increasing water discharge.

Nationell ämneskategori
Miljövetenskap
Identifikatorer
urn:nbn:se:oru:diva-64734 (URN)
Konferens
16th Symposium on remediation, Jena, Germany, October 5-6, 2017
Tillgänglig från: 2018-01-31 Skapad: 2018-01-31 Senast uppdaterad: 2022-09-28Bibliografiskt granskad
Sjöberg, S., Allard, B., Rattray, J. E., Callac, N., Grawunder, A., Ivarsson, M., . . . Dupraz, C. (2017). Rare earth element enriched birnessite in water-bearing fractures, the Ytterby mine, Sweden. Applied Geochemistry, 78, 158-171
Öppna denna publikation i ny flik eller fönster >>Rare earth element enriched birnessite in water-bearing fractures, the Ytterby mine, Sweden
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2017 (Engelska)Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 78, s. 158-171Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Characterization of a black substance exuding from fractured bedrock in a subterranean tunnel revealed a secondary manganese oxide mineralisation exceptionally enriched in rare earth elements (REE). Concentrations are among the highest observed in secondary ferromanganese precipitates in nature. The tunnel is located in the unsaturated zone at shallow depth in the former Ytterby mine, known for the discovery of yttrium, scandium, tantalum and five rare earth elements.

Elemental analysis and X-ray diffraction of the black substance establish that the main component is a manganese oxide of the birnessite type. Minor fractions of calcite, other manganese oxides, feldspars, quartz and about 1% organic matter were also found, but no iron oxides were identified. The Ytterby birnessite contains REE, as well as calcium, magnesium and traces of other metals. The REE, which constitute 1% of the dry mass and 2% of the metal content, are firmly included in the mineral structure and are not released by leaching at pH 1.5 or higher. A strong preference for the trivalent REE over divalent and monovalent metals is indicated by concentration ratios of the substance to fracture water. The REE-enriched birnessite has the general formula Mx(Mn3+,Mn4+)2O4·(H2O)n with M = (0.37–0.41) Ca + 0.02 (REE + Y), 0.04 Mg and (0.02–0.03) other metals, and with [Mn3+]/[Mn4+] = 0.86–1.00.

The influence of microorganisms on the accumulation of this REE enriched substance is demonstrated by electron paramagnetic resonance spectroscopy. Results show that it is composed of two or more manganese phases, one of which has a biogenic signature. In addition, the occurrence of C31 to C35 extended side chain hopanoids among the identified lipid biomarkers combined with the absence of ergosterol, a fungal lipid biomarker, indicate that the in-situ microbial community is bacterial rather than fungal.

Ort, förlag, år, upplaga, sidor
Elsevier, 2017
Nyckelord
Ytterby mine; Manganese oxides; Birnessite; Rare earth elements; Microbial mediation
Nationell ämneskategori
Miljövetenskap Kemi
Forskningsämne
Miljövetenskap; Kemi
Identifikatorer
urn:nbn:se:oru:diva-55316 (URN)10.1016/j.apgeochem.2016.12.021 (DOI)000395599500015 ()2-s2.0-85008339668 (Scopus ID)
Tillgänglig från: 2017-02-03 Skapad: 2017-02-03 Senast uppdaterad: 2018-02-01Bibliografiskt granskad
Schindler, F., Merbold, L., Karlsson, S., Sprocati, A. R. & Kothe, E. (2017). Seasonal change of microbial activity inmicrobially aided bioremediation. Journal of Geochemical Exploration, 174, 4-9
Öppna denna publikation i ny flik eller fönster >>Seasonal change of microbial activity inmicrobially aided bioremediation
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2017 (Engelska)Ingår i: Journal of Geochemical Exploration, ISSN 0375-6742, E-ISSN 1879-1689, Vol. 174, s. 4-9Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Microbial community patterns and their potential substrate utilization were examined to test for sustainability in metal polluted soil. The acid mine drainage (AMD) influenced test field was characterized for total soil respiration and the functional diversity of the soil bacterial communities using BIOLOG EcoPlate assays. Inoculation with the mycorrhizal fungus Rhizophagus irregularis and two streptomycetes led to an altered metabolic diversity and soil vitality, with cell numbers increased by one to three orders of magnitude. The change in metabolic activity was stable even after one winter with severe frost periods. The inoculation thus resulted in enhanced microbial activities. This vitalization resulted in enhanced formation of soil organic matter which, in turn, can sustain higher microbial cell numbers. We therefore conclude that inoculation with indigenous bacteria and a versatile mycorrhizal fungus results in improved vitality suitable for plant growth at heavy metal polluted soils. This holds a huge potential for the remediation of the legacies of mining activities and allows for land-use strategies on metal contaminated sites the world-over.

Ort, förlag, år, upplaga, sidor
Elsevier, 2017
Nyckelord
Microbial diversity, Soil function, Soil respiration, Bioremediation, Heavy metal contamination, Acid mine drainage
Nationell ämneskategori
Geofysik Geokemi
Identifikatorer
urn:nbn:se:oru:diva-54812 (URN)10.1016/j.gexplo.2016.04.001 (DOI)000390675100002 ()2-s2.0-84963542793 (Scopus ID)
Tillgänglig från: 2017-01-19 Skapad: 2017-01-19 Senast uppdaterad: 2023-12-08Bibliografiskt granskad
Rozpadek, P., Rapala-Kozik, M., Wezowicz, K., Grandin, A., Karlsson, S., Wazny, R., . . . Turnau, K. (2016). Arbuscular mycorrhiza improves yield and nutritional properties of onion (Allium cepa). Plant physiology and biochemistry (Paris), 107, 264-272
Öppna denna publikation i ny flik eller fönster >>Arbuscular mycorrhiza improves yield and nutritional properties of onion (Allium cepa)
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2016 (Engelska)Ingår i: Plant physiology and biochemistry (Paris), ISSN 0981-9428, E-ISSN 1873-2690, Vol. 107, s. 264-272Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Improving the nutritional value of commonly cultivated crops is one of the most pending problems for modern agriculture. In natural environments plants associate with a multitude of fungal microorganisms that improve plant fitness. The best described group are arbuscular mycorrhizal fungi (AMF). These fungi have been previously shown to improve the quality and yield of several common crops. In this study we tested the potential utilization of Rhizophagus irregularis in accelerating growth and increasing the content of important dietary phytochemicals in onion (Allium cepa). Our results clearly indicate that biomass production, the abundance of vitamin B1 and its analogs and organic acid concentration can be improved by inoculating the plant with AM fungi. We have shown that improved growth is accompanied with up-regulated electron transport in PSII and antioxidant enzyme activity.

Ort, förlag, år, upplaga, sidor
Paris, France: Elsevier, 2016
Nyckelord
Allium cepa, Thiamine, Rhizophagus irregularis, Biofortification, Organic acids, PSII efficiency
Nationell ämneskategori
Botanik Genetik och förädling
Identifikatorer
urn:nbn:se:oru:diva-50862 (URN)10.1016/j.plaphy.2016.06.006 (DOI)000382341600027 ()27318800 (PubMedID)2-s2.0-84974622177 (Scopus ID)
Anmärkning

Funding Agencies:

Ministry of Science and Higher Education 197/N-COST/2008/0

Marshal Office of the Malopolska Region

Jagiellonian University in Krakow funds DS/WBiNoZ/INOS/758

Tillgänglig från: 2016-06-15 Skapad: 2016-06-15 Senast uppdaterad: 2024-01-16Bibliografiskt granskad
Sartz, L., Bäckström, M., Karlsson, S. & Allard, B. (2016). Mixing of acid rock drainage with alkaline leachates: Formation of solid precipitates and pH-buffering. Mine Water and the Environment, 35(1), 64-76
Öppna denna publikation i ny flik eller fönster >>Mixing of acid rock drainage with alkaline leachates: Formation of solid precipitates and pH-buffering
2016 (Engelska)Ingår i: Mine Water and the Environment, ISSN 1025-9112, E-ISSN 1616-1068, Vol. 35, nr 1, s. 64-76Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Three metal-rich, acidic mine waters (from Bersbo and Ljusnarsberg, Sweden) were mixed with alkaline fly ash leachates in various proportions, representing a pH titration. Changes in pH and the loss of metals in solution due to precipitation of solid phases were tracked. Mineral equilibria and changes in pH and alkalinity were simulated using the geochemical code PHREEQC and the MINTEQv4 database, and the measured and simulated pH responses were compared. The formation of solid precipitates corresponded to fairly well-defined pH-buffering regions, reflecting the mine water compositions (notably the levels of Fe, Al, and Mn). Zn precipitation had a distinct buffering effect at near-neutral pH for the mine waters not dominated by iron. The formation of solid Mg phases (carbonate, as well as hydroxide) was indicated at high pH (above 9), but not formation of solid Ca phases, despite high sulfate levels. The phases that precipitated were various amorphous mixtures, mostly of the metals Fe, Al, Mn, Zn, and Mg. For the Fe-rich mine water, pH was poorly simulated with a simple MIX model, while alkalinity predictions agreed reasonably well with measured data. For the Al-rich mine waters, the simulated pH responses agreed well with the measurements. In an additional step, geochemical simulations were performed where selected proxy phases for major elements were forced to precipitate; this significantly improved the pH and alkalinity predictions. This approach may be more efficient than performing mixing experiments and titrations.

Ort, förlag, år, upplaga, sidor
Springer, 2016
Nyckelord
ARD; CFB-fly ash; PHREEQC
Nationell ämneskategori
Miljövetenskap
Forskningsämne
Kemi; Miljövetenskap
Identifikatorer
urn:nbn:se:oru:diva-47911 (URN)10.1007/s10230-015-0347-3 (DOI)000371308400008 ()2-s2.0-84959228256 (Scopus ID)
Anmärkning

Funding Agencies:

EU

Bergslagen region

Örebro University

Tillgänglig från: 2016-02-03 Skapad: 2016-02-03 Senast uppdaterad: 2024-01-16Bibliografiskt granskad
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