four fractions along the main phase of SF operations. Therefore, a preliminary study
at lab scale is required to select the suitable additives and the conditions of their use,
in order to minimize their loss caused by the first two processes over the implementation period (Ahmed Mohamed et al. 2013; Efligenir et al. 2013).
Finally, as sustainable development goals aim at supporting a cleaner production
approach, pushing away the concept of ultimate waste by supporting the idea to
reintroduce these materials into the economy (Dondi et al. 1997). For on-site
treatments, the treated soil and the building materials are usually used to fill the
excavated zones; however, the latter start to be reintroduced onto the building
materials market. About the valuation of contaminants, the market price of the
most usual metals and metalloids recovered in brownfields is ranging from 1.3 to
18 € kg
À1 (CGDD 2013). Electrolysis is often used for their simultaneous separation
and purification (Fedje et al. 2013). Recovered hydrocarbons are managed exclusively by thermal mineralization in specific treatment units usually located outside
the treated area. Nonhalogenated compounds (halogen level <0.5 %w) may be
recycled as substitute for fuel oil in cement factory if their highest heating value
(HHV) is higher than 34000 MJ ton
À1 . They may be collected by formulators for
free or bought cheap. For halogenated hydrocarbons, management costs can rise
quickly, e.g., up to 100 € ton
À1 for chlorine mass fraction between 1.5 and 2% and a
HHV lower than 2000 MJ ton
À1 . Table 1.1 presents a comparative evaluation of SW
and SF treatments (US EPA 1997; Khan et al. 2004; Dermont et al. 2008; BRGM
2010).
1.2 Current Knowledge Regarding Contaminant Behavior
Many monographs have already described the behavior of contaminants in soils and
groundwater. Herein, the knowledge about this topic is summarized and the readers
are invited to read other monographs for a more detailed information (BRGM 2008;
van der Perk 2013; Boulding and Ginn 2016).
1.2.1 Physicochemical Properties and Recalcitrance by
Groups of Contaminants
This section aims at categorizing the groups and the state of contaminants for which
leaching is relevant. In fact, it may be appropriate whenever the physical treatment
technologies used for contaminant desorption are not practicable due to either the
soil humidity or because of the low volatility of these compounds. Therefore, it is
necessary to identify nonvolatile and semi-volatile compounds (NVCs and SVCs,
respectively). Volatile compounds (VCs) are those that vaporize at room temperature
and have boiling points (BP) <200
C (Zhang 2007). These categories include
1 Contaminant Mobilization from Polluted Soils: Behavior and Reuse of Leaching. . .
9
at lab scale is required to select the suitable additives and the conditions of their use,
in order to minimize their loss caused by the first two processes over the implementation period (Ahmed Mohamed et al. 2013; Efligenir et al. 2013).
Finally, as sustainable development goals aim at supporting a cleaner production
approach, pushing away the concept of ultimate waste by supporting the idea to
reintroduce these materials into the economy (Dondi et al. 1997). For on-site
treatments, the treated soil and the building materials are usually used to fill the
excavated zones; however, the latter start to be reintroduced onto the building
materials market. About the valuation of contaminants, the market price of the
most usual metals and metalloids recovered in brownfields is ranging from 1.3 to
18 € kg
À1 (CGDD 2013). Electrolysis is often used for their simultaneous separation
and purification (Fedje et al. 2013). Recovered hydrocarbons are managed exclusively by thermal mineralization in specific treatment units usually located outside
the treated area. Nonhalogenated compounds (halogen level <0.5 %w) may be
recycled as substitute for fuel oil in cement factory if their highest heating value
(HHV) is higher than 34000 MJ ton
À1 . They may be collected by formulators for
free or bought cheap. For halogenated hydrocarbons, management costs can rise
quickly, e.g., up to 100 € ton
À1 for chlorine mass fraction between 1.5 and 2% and a
HHV lower than 2000 MJ ton
À1 . Table 1.1 presents a comparative evaluation of SW
and SF treatments (US EPA 1997; Khan et al. 2004; Dermont et al. 2008; BRGM
2010).
1.2 Current Knowledge Regarding Contaminant Behavior
Many monographs have already described the behavior of contaminants in soils and
groundwater. Herein, the knowledge about this topic is summarized and the readers
are invited to read other monographs for a more detailed information (BRGM 2008;
van der Perk 2013; Boulding and Ginn 2016).
1.2.1 Physicochemical Properties and Recalcitrance by
Groups of Contaminants
This section aims at categorizing the groups and the state of contaminants for which
leaching is relevant. In fact, it may be appropriate whenever the physical treatment
technologies used for contaminant desorption are not practicable due to either the
soil humidity or because of the low volatility of these compounds. Therefore, it is
necessary to identify nonvolatile and semi-volatile compounds (NVCs and SVCs,
respectively). Volatile compounds (VCs) are those that vaporize at room temperature
and have boiling points (BP) <200
C (Zhang 2007). These categories include
1 Contaminant Mobilization from Polluted Soils: Behavior and Reuse of Leaching. . .
9