Urea hydrolysis and recovery of nitrogen and phosphorous as MAP from stale human urine

作     者：LEE Duujong 

作者机构：Department of Chemical Engineering"National"Taiwan UniversityTaipeiTaiwan 10617China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2008年第20卷第8期

页      面：1018-1024页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 

主　　题：urea hydrolysis human urine magnesium ammomum phosphate(MAP) ammonium-nitrogen(NH_4^+-N) phosphorus 

摘      要：Laboratory-scale tests for magnesium ammonium phosphate（MAP）precipitation following urea hydrolysis of human urine were conducted using orthogonal experiment *** effects of initial pH,temperature and the volumetric ratios of stale urine to fresh urine,on urea hydrolysis in urine were studied to determine the final hydrolysis time to recover most nitrogen from separated human urine by *** a volumetric ratio of stale to fresh urine10% and at temperature≥20℃,urea hydrolysis could be completed in two *** pH inhibited urea hydrolysis *** final pH values were all around 9.0 following urine hydrolysis,while the suspension pH might act as an indicator to detect the start and extent of urea *** 95% of ammonium nitrogen and over 85% of phosphorus from hydrolyzed urine as MAP precipitate were obtained using MgCl;·6H;O and Na;HPO;·12H;O as precipitation agents at pH 8.5,molar ratio of Mg;:NH;-N:PO;-P at（1.2-1.3）:1:1,mixing speed of 120 r/min,and precipitation time and reaction time of 3 h and 15 min,*** precipitate has a structure resembling pure MAP crystal.