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Kemi, Finland

Nurmesniemi H.,Stora Enso | Poykio R.,Valtakatu 26 | Dahl O.,Aalto University | Keski R.L.,University of Oulu
Chemija | Year: 2013

In this study, the elements in the activated sludge were fractionated between acid-soluble (CH3COOH; BCR1), reducible (NH 2OH-HCl; BCR2) and oxidisable (H2O2 + CH 3COONH4; BCR3) fractions. Only the extractable concentrations of Mn (523 mg kg-1; d. w.), Ni (5.1 mg kg -1; d. w.), S (1 650 mg kg-1; d. w.) and Ti (1.3 mg kg-1; d. w.) in the BCR1 fraction were higher than those in the BCR2 fraction. The extractable concentration of Mn in the BCR1 fraction was also higher than that (160 mg kg-1; d. w.) in the BCR2 fraction and that (135 mg kg-1; d. w.) in the BCR3 fraction. However, if we disregard elements whose concentrations were lower than the detection limits, as well as Ba and Mn, the extractable concentrations of other element in the BCR3 fraction were higher than those in the BCR1 and BCR2 fractions. The recovery values (R% values), which are the ratio of sum of BCR sequential extraction procedure to the total digestion using USEPA method 3051A, varied between 81.6% (Ni) and 96.4% (V). Due to the high R% values for certain elements we would like to point out that caution must always be exercised when activated sludge is utilized and the existing legislation must always be applied. © Lietuvos mokslu̧ akademija, 2013.


Watkins G.,Aalto University | Poykio R.,Valtakatu 26 | Nurmesniemi H.,Stora Enso | Dahl O.,Aalto University | Makela M.,Aalto University
Fuel Processing Technology | Year: 2011

In Finland, the new limit values of total heavy metal, polychlorinated biphenyl (PCB) and polycyclic aromatic hydrocarbon (PAH), as well as the extractable heavy metal, dissolved organic carbon (DOC), fluoride, sulphate, and chloride concentrations for bed sand material used as an earth construction agent came into force in June 2009. The total heavy metal (i.e. Cd, Cu, Pb, Cr, Zn, As, V, Ba and Mo) concentrations in the studied bed sand material were clearly lower than the current Finnish limit values for the maximum allowable heavy metal concentrations for materials used as an earth construction agent. However, the extractable concentration of Ba (24.6 mg kg -1; d.w.) in the bed sand material exceeded the limit value for covered structures (20 mg kg -1; d.w.). However, in Finland, the competent environmental authority may relax the maximum limit values up to 30% in certain circumstances. Therefore, if, the environmental authority relaxes the maximum limit value for the extractable concentration of Ba by up to 30% to the value of 26 mg kg -1 (d.w.) for covered structures, the extractable concentration of Ba (24.6 mg kg -1; d.w.) in the bed sand material is below this relaxation. © 2011 Elsevier B.V. All rights reserved.


Poykio R.,Valtakatu 26 | Kivilinna V.-A.,Oy Metsa Botnia Ab | Nurmesniemi H.,Stora Enso
Chemija | Year: 2010

Tis study presents the most recent data on Na and Ca concentrations in Scots pine (Pi-nus sylvestris L.) needles sampled in bioindicator surveys carried out in 2009 at Kemi (Northern Finland), as well as at Pietarsaari (Western Finland) in 2007, at Eno (Eastern Finland) in 1994-1996 and in the Jyväskylä region (Central Finland) in 2006, which are areas with operating pulp and paper mills. Na and Ca concentrations in Scots pine needles at Kemi varied within 7-280 mg/kg (d. w.) and 1 410-5 450 mg/kg (d. w.), respectively. Na concentrations in both C and C + 1 needles at Kemi in 2009 were in good agreement with the values of 31-105 mg/kg (d. w.) and 54-151 mg/kg (d. w.), respectively, observed at Eno. Ca concentrations in C + 1 needles at Kemi were in good agreement with the values of 2 432-5 598 mg/kg (d. w.) observed at Pietarsaari in 2007 and with the values of 2 700-7 900 mg/kg (d. w.) observed in the Jyväskylä region in 2006, although the highest Ca concentrations - 7 900 mg/kg (d. w.) - in the C + 1 needles in the latter area was obviously higher than the corresponding value of 5 450 mg/kg (d. w.) observed in our study at Kemi. © 2012 Lietuvos mokslu̧ akademija.


Dahl O.,Aalto University | Nurmesniemi H.,Stora Enso | Poykio R.,Valtakatu 26 | Watkins G.,Aalto University
Fuel Processing Technology | Year: 2010

The total and size fractionated concentrations of As, Cd, Cr, Cu, Ni, Pb and Zn in bottom ash and two fly ash fractions from a large-sized (246 MW) fluidized bed boiler were compared to Finnish statutory limit values for forest fertilizers, which came into force in March 2007. Fly ashes were sampled from the different fields (i.e. electrodes) of the electrostatic precipitator (ESP) unit treating the stack gases. The bottom ash and the fly ash from the first ESP field are suitable for use a forest fertilizer. Due to the elevated As concentration (40 mg/kg; d.w.), which exceeded its Finnish limit value of 30 mg/kg (d.w.), the fly ash from the second ESP field is not suitable as a forest fertilizer alone. The results of ash sieving indicated that an As concentration of 40 mg/kg (d.w.) for particle size less than 0.125 mm for fly ash 2 from the second ESP electrode field exceeded the As limit value of 30 mg/kg (d.w.). In addition, a Pb concentration of 170 mg/kg (d.w.) for fly ash 1 from the first ESP electrode field for particle size 0.5-2.0 mm exceeded the Pb limit value of 150 mg/kg (d. w.). These two specific fractions are therefore not suitable for used as a forest fertilizer alone. © 2010 Elsevier B.V. All rights reserved.


Makela M.,Aalto University | Nurmesniemi H.,Stora Enso | Watkins G.,Aalto University | Poykio R.,Valtakatu 26 | Dahl O.,Aalto University
International Journal of Materials Engineering Innovation | Year: 2012

Inter-industrial utilisation of solid residues for soil amendment was investigated by combining secondary steel mill slags with residuals from a pulp and paper mill. Sample analysis included mineralogical characterisation by X-ray diffraction, relevant physicochemical properties and trace element availability by the original three-stage sequential BCR extraction procedure (CH 3COOH, NH 2OH·HCl and H 2O 2 + CH 3COONH 4) and residual fraction determination by acid digestion (USEPA 3051A). Respectively, the pseudo-total concentrations of trace elements were determined according to USEPA method 3051A. Consequently, the alkalinity of the samples (pH values 12.1-12.2) suggests significant buffering and acid neutralisation capacity with liming effect values (34.9%-35.6%, Ca-equivalents, d.w.) comparable to commercial ground limestone. This was supported by XRD, which only revealed the existence of portlandite [Ca(OH) 2] an calcite [CaCO 3]. Additionally, the pseudo-total concentrations of trace elements were lower than the respective limit values for EU soil improvers (2006/799/EC). However, Ba and V recovery during sequential extraction (Ba: 40.1-56.0 mg·kg -1, d.w., by CH 3COOH; and V: 72.2-96.5 mg·kg -1, d.w., by NH 2OH·HCl) indicates potential phytoavailability. Copyright © 2012 Inderscience Enterprises Ltd.

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