NEUTRALIZATION METHOD OF ALKALINE LEACHATE CAUSED BY SLAG

摘要

PURPOSE: A neutralization method of alkaline leachate caused by slag is provided, which adds gypsum produced from a phosphoric acid manufacturing process to the region where strong alkaline leachate is formed by contact of slag with water and so neutralizes the leachate effectively. The adding rate of gypsum is ranged from 5-6 wt.% to 30-50 wt.% according to the particle size of the slag. CONSTITUTION: The method comprises as follows: (i) add gypsum discharged from phosphoric acid process to a region where slag is in contact with water to form alkaline leachate; (ii) if the particle size of slag is less than 0.2 mm, add gypsum by 30-50 wt.%; (iii) if the particle size of the slag is less than 0.2-2 mm, add gypsum by 10-15 wt.%; and (iv) if the particle size of slag is less than 2-5.6 mm, add gypsum by 5-6 wt.%.