Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, via Claudio 21, 80125 Naples, Italy.
Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, via Gaetano di Biasio 43, 03043, Cassino, Italy.
Chemosphere. 2020 Sep;255:126977. doi: 10.1016/j.chemosphere.2020.126977. Epub 2020 May 4.
The simultaneous removal of nitrate (15 mg N-NO L) and phosphate (12 mg P-PO L) from nutrient-polluted synthetic water was investigated in a recirculated pyrite-packed biofilter (RPPB) under hydraulic retention time (HRT) ranging from 2 to 11 h. HRT values ≥ 8 h resulted in nitrate and phosphate average removal efficiency (RE) higher than 90% and 70%, respectively. Decrease of HRT to 2 h significantly reduced the RE of both nitrogen and phosphorus. The RPPB showed high resiliency as reactor performance recovered immediately after HRT increase to 5 h. Solid-phase characterization of pyrite granules and backwashing material collected from the RPPB at the end of the study revealed that iron-phosphate, -hydroxide and -sulfate precipitated in the bioreactor. Thermodynamic modeling predicted the formation of S during the study. Residence time distribution tests showed semi-complete mixing hydrodynamic flow conditions in the RPPB. The RPPB can be considered an elegant and low-cost technology coupling biological nitrogen removal to the recovery of phosphorus, iron and sulfur via chemical precipitation.
采用循环载硫生物滤池（RPPB）在水力停留时间（HRT）为 2-11 h 范围内，考察了同时去除营养污染模拟水中硝酸盐（15 mg N-NO L）和磷酸盐（12 mg P-PO L）的情况。HRT 值≥8 h 时，硝酸盐和磷酸盐的平均去除效率（RE）分别高于 90%和 70%。当 HRT 降低至 2 h 时，氮和磷的去除效率均显著降低。当 HRT 增加到 5 h 时，反应器性能立即恢复，RPPB 表现出高弹性。研究结束时从 RPPB 中收集的硫铁矿颗粒和反冲洗材料的固相特性表明，生物反应器中形成了铁磷酸盐、铁氢氧化物和铁硫酸盐。热力学模型预测在研究过程中形成 S。停留时间分布测试表明 RPPB 中存在半完全混合的水动力流条件。RPPB 可以被认为是一种优雅且低成本的技术，通过化学沉淀将生物脱氮与磷、铁和硫的回收结合在一起。
