利用白云石石灰去除与回收污泥厌氧消化液中氮和磷

Nitrogen and phosphorus removal and recovery from anaerobic digestion supernatant of sewage sludge using dolomitic lime

以白云石石灰为实验材料去除与回收污泥厌氧消化液中的氮磷,通过小试实验研究不同投药固液比S/L、初始pH值、反应温度、搅拌速度及反应时间对去除与回收氮磷效果的影响。实验结果表明,在最佳投药固液比S/L为300mg/L,最佳初始pH值范围为8.5~9.5,反应温度为25.0℃,搅拌速度为150 r/min,反应时间为24 h条件下,氨氮(NH+4-N)和磷(PO3-4-P)的去除率分别为37.26%和89.60%。利用X射线衍射仪(XRD)、扫描电镜(SEM)对沉淀产物进行了表征,通过分析可知沉淀产物中含有磷酸铵镁(MAP),可实现废水中氮磷经济有效的回收。

The method for nitrogen and phosphorus removal and recovery from anaerobic digestion supernatant of sewage sludge was constructed by using dolomitic lime. And the effects of different solid/liquid(S/L) of dolomitic lime,initial reaction pH values,temperature and reaction time on anaerobic digestion supernatant were investigated. The experimental results showed that nitrogen and phosphorus removal rates were 37. 26% and 89. 60%,respectively,under the optimal conditions of 300 mg/L dolomitic lime,pH 8. 5 ~ 9. 5,25. 0℃,150 r/min stirring and 24 h. Based on the analyses and characterization by using X-ray diffraction(XRD) and scanning electron microscope(SEM),it showed that the recovered product consisted of ammonium magnesium phosphate(MAP). This research indicated that nitrogen and phosphorus could be economically and efficiently recovered from anaerobic digestion supernatant of sewage sludge by using dolomitic lime.