磷酸铵镁沉淀法处理猪场废水的试验研究

Study on piggery wastewater by MAP treatment

磷酸铵镁沉淀法(Magnesium-Ammonium-Phosphate,MAP)是近年来迅速兴起的废水脱氮新型工艺。试验以MgCl2.6H2O和Na2HPO4.12H2O为沉淀剂,考察了pH、反应时间、反应物配比、投加方式等因素对猪场废水氨氮去除效果的影响。结果表明,在pH 9.5,n(PO43-:)n(NH4+):n(Mg2+)为1:1:1.2,反应10 min时,出水氨氮浓度为36.66 mg.L-1,去除率为95.15%,残余磷浓度为28.35 mg.L-1。且采用分段加药方式的处理效果优于一次性加药,出水氨氮浓度可降至22.74 mg.L-1,去除率升至97.26%,残余磷浓度降为15.5 mg.L-1,使MAP法处理猪场废水的工艺条件得到进一步优化。

Magnesium-ammonium-phosphate precipitation method （MAP） is a newly-developed technique to remove ammonia nitrogen from wastewater. In this study, the effects of pH, reaction time, precipitator ratio and dosing method on removal efficiency of ammonia nitrogen from piggery wastewater were investigated by using MgCI2.6H20 and Na2HPO4.12H20 as precipitators. The results showed that the effluent ammonia nitrogen concentration, removal rate and the residual phosphorus concentration reached 36.66 mg·L-1, 95.15% and 28.35 mg·L-1, respectively under the conditions of pH 9.5, n（PO4^3-）：n（NH4＋）：n （Mg2＋） equal to 1：1：1.2 within 10 min. Moreover, the treatment efficiency of stage agent additions was superior to that of one trial. The effluent ammonia nitrogen concentration, removal rate and the residual phosphorus concentration reached 22.74 mg·L-1, 97.26% and 15.5 mg·L-1, respectively. The study was conducted to optimize the reaction conditions.