鸟粪石结晶-絮凝沉淀同步法回收养殖场废水的氮磷

Simultaneous Recovery of Nitrogen and Phosphorus in Farm Wastewater by Struvite Crystallization-Flocculation Sedimentation

对采用鸟粪石结晶-絮凝沉淀同步法处理含高浓度悬浮物的养殖场废水进行了研究。结果表明,在鸟粪石结晶反应体系中加入PAM,不但有助于改善絮凝沉淀效果,而且可以提高氨氮和磷的回收效果。絮凝沉淀效果主要受PAM加药量和pH的影响,N:Mg:P摩尔比和药剂投加顺序对絮凝沉淀效果几乎没有影响。氮磷回收的最佳条件为:0.3 g/L PAM,pH=9,N:Mg:P摩尔比1:1:1。经处理后的养殖场废水氮磷占比极小,可生化性良好,能够作为反硝化的外加碳源。

The use of struvite crystallization-flocculation sedimentation synchronous method on the treatment of farm wastewater with high concentrations of suspended solids was studied. The results showed that adding PAM to the struvite crystallization reaction system could not only improve the flocculation and sedimentation effect but also improve the recovery effect of ammonia nitrogen and phosphorus. The effect of flocculation and sedimentation was mainly affected by the dosage of PAM and the pH value. The molar ratio of N: Mg: P and the order of agent addition had almost no effect on the flocculation and sedimentation. The optimal conditions for nitrogen and phosphorus recovery were: 0.3 g/L of PAM, 9 of pH,and 1:1:1 molar ratio of N: Mg: P. The treated farm wastewater has a very small proportion of nitrogen and phosphorus, good biodegradability, and can be used as an additional carbon source for denitrification.