摘要
为解决次氯酸钠(NaClO)氧化法在复杂开放的城市河道水体中治理氨氮时面临的效率不确定与生态安全风险问题,研究以阜阳城区水系为对象,通过实验室模拟与河道原位试验进行系统研究。实验室模拟中,氨氮的单位降解比例受河道本底有机物负荷影响显著,从小到大依次为盲肠段(6.40)、梅园段(7.25)、北京路桥段(12.00),与水体的三维荧光特征所表征的溶解性有机物(DOM)含量及组成呈正相关,氨氮浓度不大于4.0mg/L时,反应生成的余氯消散迅速,氨氮浓度不小于5.0mg/L时余氯残留浓度升高且半衰期显著延长,需结合水体生物活性分区实施调控策略;河道原位试验中,投加NaClO后6h内氨氮显著降低(降幅0.3~0.5mg/L),24h后余氯小于安全阈值,对鱼类生存无显著影响。基于污染物特征与生态响应,研究创新性提出的三套定制化NaClO投加方案可显著优化氨氮去除效率与生态安全性的协同调控,为城市河道精准治理提供可靠技术支撑。
To address the issues of uncertain efficiency and ecological safety risks encountered when using the sodium hypochlorite(NaClO)oxidation method to treat ammonia nitrogen in complex,open urban river waters,this paper took the river system of Fuyang urban area as the research object and conducted a systematic investigation through laboratory simulations and in situ river experiments.Laboratory simulation results indicated that the unit degradation ratio of ammonia nitrogen was significantly influenced by the background organic load of the river,with values increasing in the order of the Cecal segment(6.40),Meiyuan segment(7.25),and Beijing road bridge segment(12.00).This trend showed a positive correlation with the content and composition of DOM,as characterized by the three-dimensional fluorescence characteristics of the water body revealing the competitive consumption mechanism of DOM for oxidants.When the ammonia nitrogen concentration was not more than 4.0 mg/L,the residual chlorine generated by the reaction dissipated rapidly.However,when the ammonia nitrogen concentration was not less than 5.0 mg/L,the residual chlorine concentration increased,and its half-life significantly prolonged,necessitating regulation strategies based on the biological activity zoning of the water body.In-situ river experiments demonstrated a significant reduction in ammonia nitrogen(0.3~0.5 mg/L)within 6 hours after sodium hypochlorite dosing,with residual chlorine decaying to less than the safe threshold after 24 hours,with on-site qualitative observations indicating no significant impacted on fish survival.Based on pollutant characteristics and ecological responses,this paper innovatively proposed three customized sodium hypochlorite dosing schemes,optimizing the synergistic regulation of ammonia nitrogen removal efficiency and ecological safety,thereby providing reliable technical support for the precise management of urban rivers.
作者
聂菊仙
卢庆根
崔健
程庆庆
张勇
张爱勇
NIE Juxian;LU Qinggen;CUI Jian;CHENG Qingqing;ZHANG Yong;ZHANG Aiyong(Fuyang China Electric Power Construction Botian Water Environment Treatment Co.,LTD.,Fuyang 236000,China;CEWUD Group Co.,Ltd.,Anhui Branch,Hefei 230000,China;School of Civil and Hydraulic Engineering,Hefei University of Technology,Hefei 230009,China)
出处
《江淮水利科技》
2025年第6期21-28,共8页
Jianghuai Water Resources Science and Technology
基金
安徽省自然科学基金水科学联合基金(2408055US005)。
关键词
次氯酸钠
氨氮
净化水质
余氯衰减
城市河道
sodium hypochlorite
ammonia nitrogen
purify water quality
residual chlorine attenuation
urban river course
