| Title |
Leaching Characteristics of Calcium Ion from Granular Converter Slag as Phosphorus Crystallizer |
| Authors |
김응호 ; 허순철 ; 조진규 ( Eoung Ho Kim ; Soon Cheol Hur ; Jin Kyu Cho ) |
| Abstract |
Calcium ion and pH of leachate from converter slag as phosphorus crystallizer were measured with respect to diameter and space velocity(SV) for stable crystallization. Since conventional crystallization process in municipal wastewater treatment requires calcium concentration over 70㎎/L and usually secondary effluent includes Caz^(2+) concentration of 40㎎/L, it must be leached above 30㎎/L from converter slag itself which is the critical concentration to judge the effective slag duration. Diameter of used slag was ranged from 0.4 to 2.0㎜. As the leaching pH of all slag media is over 11.0, the slag process needs the additional pH decreasing adjustment. When using below l.0㎜ diameter of slag media under the space velocity of 2hr^(-1), the effective duration lasted 40days. When using slag ranged from 0.42 to 2.0㎜ under the space velocity of lhr^(-1) and 2hr^(-1) , the effluent Ca^(2+) concentration maintained over 30㎎/L until 40days, but in case of SV of 3hr or above the critical 30㎎/L cannot be obtained from initial operation. |