磷酸铵镁—电氧化一体化集成技术同步脱氮除磷效率及机制

Urine is a major source of nitrogen and phosphorus pollution in urban domestic sewage, which is one of the major causes of water pollution. Urine is a major source of nitrogen and phosphorus pollution in urban domestic sewage, which is one of the major causes of water pollution. The key problem related to the wastewater is that there exist great difficulties for simultaneous nitrate, ammonium and phosphate removal, this project puts forward a novel struvite-electrochemical integrated technology approach and focuses on urine for simultaneous nitrogen and phosphorus effectively decrease at the pump. Struvite- electrochemical crystallization procedure (Mg electrodes) can be realized to recycle phosphate and part of ammonium on effectively from urine, the dynamic process and reaction rule of struvite- electrochemical crystallization for phosphate and ammonium recycle will be employed, and we will conclude the value drivers; a novel and highly effective wastewater treatment facility-integral electrochemical reactor will be designed for simultaneous residual ammonium, nitrate and COD removal from the supernate of urine (anodic switching), the competitive oxidative pathway and the key factors of residual ammonium, COD and nitrate synchronous electrochemical reduction removal from the supernate of urine will be investigated, the electrical oxidation mechanism and the value drivers will be interpreted under the condition of high ionic strength; the mechanism of electrode passivation blocked by scrap iron with fluidized state will be explained, the effect of ammonium, COD electrochemical oxidation and nitrate electrochemical reduction by scrap iron with fluidized state; the implementation of this project will provide a novel struvite-electrochemical integrated device approach for simultaneous nitrogen and phosphorus removal. The conduction of this project will provide a strong theoretical guidance for simultaneous ammonium, nitrate and phosphate removal from wastewater.

尿液是城市污水中污染物的主要来源，而城市污水是环境水体污染的主要来源之一。本项目针对污水处理工艺中硝氮、氨氮和磷酸盐难于同步去除的关键科学问题，提出采用磷酸铵镁—电氧化一体化集成技术，以尿液为研究对象，从源头上同步高效降低城市污水中的硝氮、氨氮和磷酸盐含量。通过磷酸铵镁—电化学(镁电极)结晶法去除尿液中的磷酸盐和部分氨氮，探明磷酸铵镁—电化学结晶法的动力学过程和反应规律，并揭示关键驱动因子；同时设计一款高效一体化反应器，同步降解尿液中过剩的氨氮、硝氮和COD (阳极切换)，探明残留液中氨氮、COD的竞争氧化途径、硝氮同步还原规律及关键影响因素，揭示高离子强度条件下氨氮、COD电氧化/硝氮电还原机制以及关键控制因子；探讨流化态铁屑阻碍电极钝化的作用机制以及其形成的类酚顿体系对氨氮和COD氧化/硝氮还原的影响。本项目将为污水中氨氮、硝氮及磷酸盐的同步去除提供强有力的理论依据。

尿液是城市污水中污染物的主要来源，而城市污水是环境水体污染的主要来源之一。本项目针对污水处理工艺中硝氮、氨氮和磷酸盐难于同步去除的关键科学问题，提出采用磷酸铵镁——电氧化一体化集成技术，以尿液为研究对象，从源头上同步高效降低城市污水中的硝氮、氨氮和磷酸盐含量。通过设计的高效一体化反应器，采用磷酸铵镁电化学结晶除磷以及电氧化脱氮同步去除废水中的磷酸盐和氮。实验结果表明，磷酸铵镁电化学结晶过程中，电流密度为15 mA cm-2，电解时间为20 min时，磷酸盐去除效率超过11 mg P cm−2 h−1；在电氧化过程中，当电流密度为45 m A cm−2，电解时间 60 min时，氨氮和总氮去除效率分别达到80%和75%。电流密度、电解时间以及起始pH是磷酸铵镁电化学除磷和电氧化脱氮的关键控制因素；磷酸铵镁——电氧化一体同步脱氮除磷过程中，pH值是电氧化脱氮的关键控制因素，一体化同步脱氮除磷效率分别达到78%和96%。本项目设计的电化学单反应器，将为分散式小区生活污水处理以及尿液的原位处理提供技术支持和应用选择。