Stabilisation of highly polluted soils and tailings using phosphates

Xenidis, A; Stouraiti, C; Paspaliaris, I

dc.contributor.author	Xenidis, A	en
dc.contributor.author	Stouraiti, C	en
dc.contributor.author	Paspaliaris, I	en
dc.date.accessioned	2014-03-01T02:48:46Z
dc.date.available	2014-03-01T02:48:46Z
dc.date.issued	1999	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/34097
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-0033488571&partnerID=40&md5=b50aacec400f20da19687003c584f67d	en
dc.title	Stabilisation of highly polluted soils and tailings using phosphates	en
heal.type	conferenceItem	en
heal.publicationDate	1999	en
heal.abstract	Mining and metallurgical activities throughout the world resulted in the formation of huge stockpiles of mining wastes containing heavy metals and toxic elements. Due to improper environmental management of these wastes, contaminants migrate by several physical and chemical mechanisms contributing to the pollution of surrounding soils as well as surface and ground waters. In the present paper, the effectiveness of stabilisation techniques aiming at converting the contaminants to low solubility, mobility and bioavailability forms, is studied. Oxidic tailings and contaminated soil samples originating from Lavrion (Greece) and Montevecchio (Sardinia, Italy) areas were tested. Lead is considered as the key contaminant for the above materials, since it is present in high content and exhibits solubility well above TCLP EPA regulatory limit. For lead immobilisation, calcium oxyphosphate was added in the contaminated materials aiming at the formation of low solubility lead phosphates. One month long pot experiments were carried out on mixtures of tailings or soils with calcium oxyphosphate. Stabilisation of the heavy metals in the tailings or soil was examined by applying mainly chemical extraction tests (EPA TCLP and EDTA) and complementary biological tests, which involved growing of dwarf beans. The results showed that phosphate doses of 0.89, 1.37, 0.21 and 0.69 w/w for Lavrion tailings and soils and Montevecchio tailings and soils respectively were sufficient to reduce lead solubility well below the EPA TCLP regulatory limit. Moreover, lead bioavailability, as determined in the EDTA test, was significantly reduced with the stabilisation. However, biological tests using dwarf beans as plant indicator showed that the applied doses of phosphates hindered the plant growth.	en
heal.journalName	Proceedings of the TMS Fall Extraction and Processing Conference	en
dc.identifier.volume	3	en
dc.identifier.spage	2153	en
dc.identifier.epage	2162	en