| 摘要 |
PROBLEM TO BE SOLVED: To provide a low-cost treatment process using general-purpose facilities for neutralizing waste water containing suspended matters from which calcium ions are eluted so as to remove calcium by coagulation settling.SOLUTION: The method for processing alkaline waste water including calcium-eluting particles comprises the following steps. In a first step, suspended matters contained in raw water are precipitated for removal in a sand basin. In a subsequent second step, a calcium scavenger is added to precipitate calcium ions as a calcium salt. Because of this, agitation is performed in a tank for addition of the calcium scavenger, in order to prevent the sedimentation of the calcium salt. In a third step, the calcium salt-containing raw water is processed in a neutralization tank for neutralizing positive ions as electrolytes. Subsequently a calcium flock (aggregate) is formed from calcium ions using an inorganic coagulant, an organic coagulant, or both of the coagulants in a coagulation tank. The flock is precipitated in a settling tank. |
