Title: Reactive walls and filters of iron shavings – an overview 
Resource Type: document --> technical publication --> report 
Country: Denmark 
Language(s): Danish
Year: 2004 
Availability: Environmental project, Miljørapport nr. 916 
Author 1/Producer: Kjeldsen, P. 
Author / Producer Type: Agency, regulator or other governmental or inter-governmental body 
Publisher: The Danish Environmental Protection Agency, Miljøstyrelsen 
Publisher City: Strandgade 29, DK-1405 Copenhagen K, Denmark 
ISBN: 87-7614-229-9 
Report / download web link (=direct link): http://www2.mst.dk/common/Udgivramme/Frame.asp?pg=http://www ...  
Format (e.g. PDF): PDF 
Size: (e.g. 20mb) 1.596 
EUGRIS Keyword(s): Contaminated land-->Remediation options-->Permeable reactive barriers
Short description: The report gives an overview of processes and research using zero-valent iron for treatment of contaminated groundwater, and alternative technological construction methods. Demonstration projects carried out under the Danish EPA Technology Programme for Soil and Groundwater Contamination are presented as well as a detailed status of treatment technologies. 
Long description: Permeable reactive barriers and on-site canisters containing zero-valent iron are technologies for treatment of contaminated groundwater. Iron filings have – by the anaerobic corrosion process - a potential for degradation of many types of organic pollutants, especially chlorinated compounds. Iron filings can also treat many inorganic compounds such as chromate, arsenic, and nitrate, by reduction, precipitation, and adsorption processes. Technologies combining other metals with the iron filings have been developed in order to enhance the reactivity of the material. Five Danish field projects were carried out: three permeable reactive barriers (PRBs), and two on-site groundwater treatment canisters. A relatively limited capacity for chromate removal was demonstrated in one project. Several of the reactors containing organic materials showed removal of chlorinated solvents. The most important issues to consider are controlling the hydraulic conditions of permeable reactive barriers to ensure homogeneous retention times within the iron barrier, and the long-term reactivity of the iron material. Due to changes of the chemistry of the groundwater passing through the barrier, several compounds may be retained by precipitation and adsorption processes affecting the reactivity of the iron surfaces leading to reduced degradation rates and/or limited capacities for chromate removal. 
Submitted By: Dr Jacqueline Falkenberg WhoDoesWhat?      Last update: 02/04/2007