Water-Soluble Cr (VI) of Solidification-Cured Process and Compressive Strength of Ferrochrome Slag Complex Cement

Ferrochrome slag, an essential component in stainless steel, is the by-product of ferrochromium production. The composition of the ferrochrome slag and leaching tests show that the chromium content, 3.68%, is high, although the data of leaching tests under normal conditions is very low. Leaching test was performed on an oscillating shaking table with ratio adjusted to 150r/min at L/S 8 and 80°C, during 5h. The maximum content of water-soluble Cr (Ⅵ) is 2.78μg/g (0.3475 mg/L) from ferrochromium slag under these conditions. The soluble (Cr6+ and Cr3+) content rise in the solidification process，with the increase of ferrochrome slag. The Water-soluble Cr (Cr6+ and Cr3+) under different cured times can’t be detected. The content of ferrochrome slag reached 10% is the best ratio by comprehensive consideration of water-soluble Cr (Ⅵ) of all processes, compressive strength and relevant national standards.