Due to the different chemical characteristics of Arsenic from Cadmium, Lead, Copper, many different remediation methods have been applied to the arsenic-contaminated soil. In many cases, general particle size range of soils were tested.
Very small ...
Due to the different chemical characteristics of Arsenic from Cadmium, Lead, Copper, many different remediation methods have been applied to the arsenic-contaminated soil. In many cases, general particle size range of soils were tested.
Very small size soil particles after soil washing (0.075mm below) are usually treated as waste material (arsenic concentration 55.4 mg/kg). In this study, the best avaliable technology to reduce the remediation cost was investigated on the 0.01 ∼ 0.075mm particle size range soil.
In this study, (1) portland cement and calcium oxide (Ca(OH)2) were applied as stabilization agents. And (2) phosphate(PO43-) and portland cement/calcium oxide were sequentially applied as washing agent and stabilization agents, respectively.
87.8% stabilization effect was achieved when portland cement (20%, weight ratio) was applied. And when calcium oxide (5%, wt) and portland cement (20%, wt) were applied, 93.4% stabilization effect was achieved.
Wasing efficiency was 69.0% after re-wasing using 2M KH2PO4. When calcium oxide (5%, wt) was applied to rewashing soil (Sample B-2), total stabilization effect was 99.5%.
Therefore, when the remediation of small size particle arsenic-sontaminated soil is needed, several methods are applicable depending on the stabilztion efficiency. (1) portland cement and calcium oxide were applied as stabilization agents. And (2) phosphate and portland cement/calcium oxide were sequentially applied as washing agent and stabilization agents, respectively.