Lee S I, Weon S Y, Lee C W, Koopman B
Department of Environmental Engineering, Chungbuk National University, Cheongju, 361-763, Republic of Korea.
Chemosphere. 2003 Apr;51(4):265-71. doi: 10.1016/S0045-6535(02)00807-X.
Removal of nitrogen and phosphate through crystallization of struvite (MgNH(4)PO(4).6H(2)O) has gained increasing interest. Since wastewaters tend to be low in magnesium relative to ammonia and phosphates, addition of this mineral is usually required to effect the struvite crystallization process. The present study evaluated the feasibility of using bittern, a byproduct of salt manufacture, as a low-cost source of magnesium ions. High reaction rates were observed; the extent of nitrogen and phosphorus removals did not change beyond 10 min. Phosphorus removals from pure solutions with bittern added were equivalent to those obtained with MgCl(2) or seawater. Nitrogen removals with bittern were somewhat lower than with the alternate Mg(2+) sources, however. Application of bittern to biologically treated wastewater from a swine farm achieved high phosphate removal, but ammonia removals were limited by imbalance in the nitrogen:phosphorus ratio.
通过鸟粪石(MgNH(4)PO(4).6H(2)O)结晶去除氮和磷越来越受到关注。由于废水相对于氨和磷酸盐而言往往镁含量较低,通常需要添加这种矿物质来实现鸟粪石结晶过程。本研究评估了使用制盐副产品卤水作为镁离子低成本来源的可行性。观察到反应速率很高;10分钟后氮和磷的去除程度没有变化。添加卤水的纯溶液中的磷去除率与使用MgCl(2)或海水时相当。然而,用卤水去除氮的效果略低于使用其他镁离子来源。将卤水应用于猪场生物处理后的废水,实现了高磷酸盐去除率,但氨的去除受到氮磷比失衡的限制。