Change search
ReferencesLink to record
Permanent link

Direct link
Stabilisation of CCA-contaminated soil: assessment of amendments for immobilization of chromate cupper arsenate (CCA)
2004 (English)Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

Stabilisation of trace element contaminated soil is a soil remediation method used to reduce the mobile fraction of critical elements in the soil using soil additives (amendments). The stabilisation of trace elements occurs through i.e. sorption, co-precipitation or complex formation. In this work, different amendments and combinations of amendments have been added to chromate cupper arsenate (CCA) contaminated soil collected at a former wood preservation site at Robertsfors works, Sweden. The amendments used in the experiments were blast furnace slag (BFS), zerovalent iron (Fe0), blaster sand (BS), coal fly ash (CFA) and peat. The changes in the element mobility were tested performing standard compliance batch leaching tests at L/S (liquid to solid ratio) 2 and 10. The purpose of the investigation was to increase knowledge about the behavior of the trace elements occurring in CCA contaminated soil when adding different amendments. One goal was to identify an amendment or combination of amendments that effectively stabilized the contaminants (reducing the mobility of the contaminants). A second goal was to test how the effectiveness of the selected amendment changed in different geochemical environments. To vary the geochemical environment the parameters pH, amount of water added to the soil and redox potential were controlled. The evaluation of the results was based on the leaching of As, but the behavior of the other trace elements e.g. chromium, copper was also considered. All amendments added alone decreased the mobility of As, except for peat which increased the amount of As in the leachate about 4 times. The most effective amendment to decrease the leaching of As was Fe0 alone. Fe0 also decreased the leaching of Cr, Cu and Zn. A combination of amendments that effectively reduced the mobility of the trace elements was Fe0 and BFS together. When more water was added to the soil (L/S 10) it was observed that Fe0 alone worked more effectively than the combination of BFS and Fe0. Further investigations were made for the soil treated with Fe0. The effect of redox could not be evaluated because the treatment with nitrogen gas of the samples during the leaching did not permit to reach low redox potential, i.e. to reach oxygen free conditions. The amount of water that was in contact with the soil had less effect on the mobility of As than the pH in the leachant. The pH was kept constant at pH 3, 5 and 8. The least amount of As was leached from the soil when pH was kept at 5.

Place, publisher, year, edition, pages
Keyword [en]
Technology, miljö, förorenad mark, miljögeoteknik, krom, koppar, arsenik, avfallsteknik, nollvärt järn, torv, contaminated soil, phytostabilisering, stabilisering, mobility, arsenic, cupper, chromium, CCA, peat, zerovalent iron, blaster sand, coal fly, ash
Keyword [sv]
URN: urn:nbn:se:ltu:diva-44708ISRN: LTU-EX--04/303--SELocal ID: 2792724e-3760-43dd-96f4-ca073d75999fOAI: diva2:1017987
Subject / course
Student thesis, at least 30 credits
Educational program
Environmental Engineering, master's level
Validerat; 20101217 (root)Available from: 2016-10-04 Created: 2016-10-04Bibliographically approved

Open Access in DiVA

fulltext(716 kB)0 downloads
File information
File name FULLTEXT01.pdfFile size 716 kBChecksum SHA-512
Type fulltextMimetype application/pdf

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

ReferencesLink to record
Permanent link

Direct link