摘要
采用鸟粪石沉淀(MAP)法同时回收某酒厂厌氧工艺出水中的氮和磷,以MgO取代MgCl_2作为沉淀剂,研究了不同pH值、镁磷摩尔比和反应时间对N、P回收率的影响.结果表明:在pH=9.6,n(Mg^(2+))︰n(P)=1︰1,反应时间为20 min的最佳回收工艺条件下,总磷和氨氮的回收率分别高达98.0%和30.9%,同样条件下氨氮的挥发率为7.2%.生成的鸟粪石沉淀物的SEM分析结果显示:其结晶体为斜方型晶体,表面有絮状物和微粒附着;XRD半定量分析表明:沉淀物中鸟粪石的含量高达94%,属于利用价值极高的缓释化肥.每1000 m3的酒厂厌氧出水通过投加0.16 t的氧化镁和微量的氢氧化钠可以回收1.01 t的高纯度(90%)鸟粪石,具有极高的经济价值.
Struvite precipitation （ MAP） was used to recover the nitrogen and phosphorus at the same time from the anaerobic treated effluent of distillery wastewater and MgCl2 was replaced by MgO as a new precipitant during the test. Meanwhile, influences of pH, molar ratio between Mg and P, and reacting time on nitrogen and phosphorus recovering performances were investigated. The results indicated that under optimum condition [ n （ Mg^2 ＋ ） n （P ）= 1 ： 1 ,pH = 9. 6, stirring time of 20 minutes] ,98% of total phosphorus and 30. 9% of ammonia were recovered. In addition, 7. 2% of ammonia was removed as volatilization under the same conditions. The precipitated struvite was analyzed by SEM and showed that the sediment was orthorhombic crystal and some floccules and particles were adhered on its crystal surface. XRD semi-quantitative analysis indicated the purity of MAP sediments was up to 94% , which could be used as a promising slow-release fertilizer. Moreover, 1.01 t high purity （above 90% ） struvite could be recovered by adding 0. 16 t MgO and a little bit NaOH to 1000 m3 anaerobic treated wastewater, suggesting it is a technology of high economic value.
出处
《中南民族大学学报（自然科学版）》
CAS
北大核心
2016年第3期1-5,共5页
Journal of South-Central University for Nationalities：Natural Science Edition
基金
国家自然科学基金资助项目(30800021)
湖北省科技支撑资助计划(2014BEC029)
关键词
鸟粪石
酒厂厌氧废水
氮磷回收
晶型分析
struvite
UASB treating swine wastewater
recovery of nitrogen and phosphorus
crystal analysis
