Effect of hydraulic retention time and seed material on phosphorus recovery and crystal size from urine in an air-agitated reactor.
Phosphorus (P) recovery from urine is affected by various parameters. This study evaluates the effects of hydraulic retention time (HRT) and seed material on P recovery and crystal size in an air-agitated reactor. Results show that ortho-phosphate removal and struvite recovery efficiencies were 96.3% and 89.5%, and 97.1% and 93.0%, after five runs of HRTs of 1 and 2 h, respectively. Low loss of crystals from effluent urine solutions indicates high struvite recovery efficiency and is correlated with the structure and design of the reactor. The average particle size decreased from 40.0 to 31.7 μm as the HRT increased from 1 to 2 h. The two types of seed materials (zeolite and molecular sieve) did not affect the ortho-phosphate removal efficiency but affected the struvite crystal size. In particular, multi-stage addition of zeolites increased the average crystal size from 33.7 to 57.0 μm.
College of Resources and Environment, University of Chinese Academy of Sciences, 19A, Yuquan Road, Shijingshan District, Beijing 100049, China E-mail: zhyhu@ucas.ac.cn.
Xiaoning
X
Liu
College of Resources and Environment, University of Chinese Academy of Sciences, 19A, Yuquan Road, Shijingshan District, Beijing 100049, China E-mail: zhyhu@ucas.ac.cn.
Zhengyi
Z
Hu
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Jinzhi
J
Wang
College of Resources and Environment, University of Chinese Academy of Sciences, 19A, Yuquan Road, Shijingshan District, Beijing 100049, China E-mail: zhyhu@ucas.ac.cn.
Guoqi
G
Wen
D003460:Crystallization; D006801:Humans; D010758:Phosphorus / Q000302:isolation & purification*; D013997:Time Factors; D014556:Urine / Q000737:chemistry*
D010758:Phosphorus