MnO_(x)同步除锰氨氮滤池的快速启动及污染物去除机制

Rapid start-up and pollutant removal mechanism of MnO_(x) filter for simultaneous removal of manganese and ammonium

通过将MnO_(x)负载于石英砂表面形成MnO_(x)滤料,并以此构筑滤池,开展动态试验,考察了滤池的启动周期、污染物去除效率及影响因素;同时通过表征MnO_(x)结构变化和灭活滤料表面微生物等方法探究了MnO_(x)滤池的污染物去除机制.结果表明:运行第1d滤池出水锰即可达标,运行至第9d,滤池启动完成,可实现对水中锰和氨氮的同步有效去除.滤池可稳定同步去除锰和氨氮的最大平均浓度分别为1.4和1.6mg/L,滤速为6m/h,且通过提升水中溶解氧含量可进一步增强滤池对锰和氨氮的去除效果.SEM、EDS和XRD分析结果表明,滤池运行过程中,MnO_(x)由相对密实的颗粒堆积形态逐步发展为多孔的一体化海绵状结构,其组成由ramsdellite和birnessite型MnO_(2),逐步发展为buserite和birnessite型MnO_(2),但元素组成相对较为稳定.结合滤料表面的微生物灭活实验,认为滤池稳定运行阶段,MnO_(x)对锰的去除主要为非生物作用,对氨氮的去除以生物作用为主,化学催化氧化和吸附作用分别占16.9%~23.6%和4.4%~11%.研究结果将为利用MnO_(x)促进锰和氨氮高效过滤去除技术的发展提供理论和技术支撑.

A dynamic experiment was conducted by coating MnO_(x)on the surface of quartz sand to form MnO_(x)filter media and constructing a filter with it.The start-up period,pollutant removal efficiency and influencing factors of the filter were investigated and the pollutant removal mechanism of the MnO_(x)filter was explored by characterizing the structural changes of MnO_(x)and inactivating the microorganisms on the surface of the filter media.The results showed that the manganese in the effluent of the filter can meet the standard in the first day of operation,and it can achieve the simultaneous and effective removal of manganese and ammonium from water when the filter starts to complete in the 9th day of operation.The maximum average concentrations of manganese and ammonium were 1.4 and 1.6 mg/L respectively at the filtration rate of 6 m/h.The efficient removal of manganese and ammonium could be further enhanced by increasing the dissolved oxygen content in the water.The results of SEM,EDS and XRD analysis showed that during the operation of the filter,MnO_(x)gradually developed from a relatively dense particle accumulation morphology to a porous integrated sponge-like structure,and its composition gradually developed from ramsdellite and birnessite type MnO_(2)to buserite and birnessite type MnO_(2),but the elemental composition was relatively stable.Combined with the microbial inactivation experiments on surface of the filter media,it was concluded that the removal of manganese from the filter during the stable operation stage was mainly abiotic,and the removal of ammonium was mainly biological,with chemical catalytic oxidation and adsorption accounting for 16.9%~23.6%and 4.4%~11%,respectively.The results of the study will provide theoretical and technical support for the development of efficient filtration removal technologies for manganese and ammonium using MnO_(x).