Laboratory of Environmental Technology, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.
Laboratory of Environmental Technology, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.
Sci Total Environ. 2020 Feb 25;705:135959. doi: 10.1016/j.scitotenv.2019.135959. Epub 2019 Dec 5.
The sustainable management and recirculation of phosphorus resources are essential to our human lives. In this work, phosphorus removal and recovery from secondary effluent were achieved using municipal wastewater-derived materials as adsorbents. Through modification with 0.5 M NaOH for 30 min, iron containing sludge that originated from the coagulation pretreatment of municipal wastewater was successfully converted to phosphorus adsorbent. The maximal adsorption capacity of the prepared adsorbent was estimated to be 22 mg-P/g, and the adsorption performance remained stable in the pH range of 5-8. FeO(OH) was identified as the key adsorption site, and the ligand exchange mediated chemical adsorption was the main mechanism for phosphorus removal by the prepared material. Moreover, a laboratory-scale continuous-flow adsorption column experiment showed that the surplus phosphorus in secondary effluent could be readily reduced to <0.1 mg/L. By pyrolysis of P-laden alkali-treated iron sludge under oxygen limited conditions, the phosphorus was recovered and successfully applied to support wheat growth. This work provides valuable information for both the sustainable management of phosphorus streams in wastewater and cyclic utilization of waste sludge.
可持续管理和磷资源的再循环对人类生活至关重要。在这项工作中，使用城市废水衍生的材料作为吸附剂从二级出水去除和回收磷。通过用 0.5 M NaOH 改性 30 分钟，成功地将源自城市废水混凝预处理的含铁污泥转化为磷吸附剂。制备的吸附剂的最大吸附容量估计为 22 mg-P/g，并且在 pH 值为 5-8 的范围内吸附性能保持稳定。FeO(OH)被确定为关键的吸附位点，配位交换介导的化学吸附是该材料去除磷的主要机制。此外，实验室规模的连续流动吸附柱实验表明，可以很容易地将二级出水中的剩余磷降低到<0.1 mg/L 以下。通过在有限氧条件下对含磷的碱处理铁污泥进行热解，可以回收磷，并成功地用于支持小麦生长。这项工作为废水磷流的可持续管理和废污泥的循环利用提供了有价值的信息。
