A major environmental risk factor, associated with the use of construction materials, is their potential emission of pollutants and their migration in the aqueous medium (groundwater, surface water and precipitation).

The paper aim is to evaluate the environmental properties of concrete with cement manufactured by using of the alternative fuel.

Concrete matrix ability of heavy metals immobilization was assessed experimentally by appropriate leaching tests. Dynamic surface leaching test on monolithic concrete samples simulates release of contaminants from concrete products during service life. The potential leaching characteristics of the concrete after demolition were estimated by the extraction test, with assessment of the leaching availability (or the maximum leaching fraction). Also, there carried out the extractions at different values of pH for establishment the pH influence on heavy metals leaching.

The emission values of heavy metals from monolithic concrete samples after 64 days were compared with the regulated, as according to Dutch Building Materials Decree (DMBD). The release values of the heavy metals from concrete were well  below of the DMBD regulated criteria, referring to categoria I of construction materials.

The extraction test results showed that pH plays a crucial role on the heavy metals leachability. The cationic contaminants (Mn, Ni, Co, and Cu) were leached at  pH values

< 7. The cations solubility is  much lower than that of the oxyanionic   in  the alkaline aqueous medium of  concrete pore with pH ≥ 12.5. The higher alkalinity of leachate provided from alkaline character of cement matrix was  favorable to leach of Cr (VI), As (V), Sb (V) and V (V) as oxyanions.

The experimental results obtained can be a contribution referring to assessing the environmentally friendly character of the concrete due  cementitious matrix ability to heavy metals immobilization.




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