“In situ” remediation technologies, if applied without careful evaluation of the process parameters, may themselves be a source of pollution. The soil flushing is a useful technology for in situ remediation of a heavy metal contaminated soil and is particularly effective when the washing solution is added with a chelating agent such as EDTA. Excessive use of chelating agent may, however, be harmful to the environment for several reasons: the chelating solution, if incompletely intercepted by extraction wells, can reach the water table; an excessive concentration of chelator can damage soil structure and finally the metal transported by the chelating solution can be reabsorbed into the deeper layers of the soil. This paper presents the results of a soil flushing treatment with a EDTA solution carried out on an experimental soil column that consists of a surface layer contaminated with lead and a not contaminated deeper layer. The purpose of the study is to determine whether a part of the metal contained into the superficial contaminated soil can be transferred, by the chelating solution, in the uncontaminated soil; furthermore the concentration of the chelating agent and the volume of the solution that minimizes the risk for the soil are determined by 1D model that simulates the chelation process. The experimental results confirm the possibility that a small amount of metal can be transferred and absorbed into the not contaminated soil. Operationally this information can be used to define the correct positioning of the extraction wells used in the soil flushing; at the same simulation model can be used to determine the concentration and volume of chelating solution that optimize the treatment.
NUMERICAL MODEL FOR CHELATING AGENTS ENHANCED SOIL FLUSHING / Antonucci, Angela; Lamberti, Mafalda; Luciano, Antonella; Mancini, Giuseppe; Martorelli, Elisa; Torretta, Vincenzo; Viotti, Paolo. - STAMPA. - (2015), pp. 1-5. (Intervento presentato al convegno 14th International Conference on Environmental Science and Technology (CEST2015) tenutosi a Rhodes, Greece nel 3-5 September 2015).
NUMERICAL MODEL FOR CHELATING AGENTS ENHANCED SOIL FLUSHING
ANTONUCCI, ANGELA;MARTORELLI, ELISA;VIOTTI, Paolo
2015
Abstract
“In situ” remediation technologies, if applied without careful evaluation of the process parameters, may themselves be a source of pollution. The soil flushing is a useful technology for in situ remediation of a heavy metal contaminated soil and is particularly effective when the washing solution is added with a chelating agent such as EDTA. Excessive use of chelating agent may, however, be harmful to the environment for several reasons: the chelating solution, if incompletely intercepted by extraction wells, can reach the water table; an excessive concentration of chelator can damage soil structure and finally the metal transported by the chelating solution can be reabsorbed into the deeper layers of the soil. This paper presents the results of a soil flushing treatment with a EDTA solution carried out on an experimental soil column that consists of a surface layer contaminated with lead and a not contaminated deeper layer. The purpose of the study is to determine whether a part of the metal contained into the superficial contaminated soil can be transferred, by the chelating solution, in the uncontaminated soil; furthermore the concentration of the chelating agent and the volume of the solution that minimizes the risk for the soil are determined by 1D model that simulates the chelation process. The experimental results confirm the possibility that a small amount of metal can be transferred and absorbed into the not contaminated soil. Operationally this information can be used to define the correct positioning of the extraction wells used in the soil flushing; at the same simulation model can be used to determine the concentration and volume of chelating solution that optimize the treatment.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
