扬水曝气诱导自然混合持续改善水质效果评价  

Assessment of water quality improvement through continuous natural mixing induced by WLAs

作　　者：张春晓 黄廷林[1,2] 张轩[1,2] 刘宇轩 宋云霞 温成成 蔡晓春 ZHANG Chunxiao;HUANG Tinglin;ZHANG Xuan;LIU Yuxuan;SONG Yunxia;WEN Chengcheng;CAI Xiaochun(Collaborative Innovation Center of Water Pollution Control and Water Quality Security Assurance of Shaanxi Province,Xi'an University of Architecture and Technology,Xi'an 710055;Shaanxi Provincial Field Scientific Observation and Research Station of Water Quality in Qinling Mountains,Xi'an University of Architecture and Technology,Xi'an 710055;Xi'an Water Supply Corporation(Group)Lijiahe Reservoir Management Co.Ltd,Xi'an 710016)

机构地区：[1]西安建筑科技大学,陕西省水污染控制与水质安全保障协同创新中心,西安710055 [2]西安建筑科技大学,秦岭水源地水质陕西省野外科学观测研究站,西安710055 [3]西安水务(集团)李家河水库管理有限公司,西安710016

出　　处：《环境科学学报》2024年第10期185-196,共12页Acta Scientiae Circumstantiae

基　　金：国家重点研发计划(No.2022YFC3203604);陕西省重点研发计划(No.2022ZDLSF06-08)。

摘　　要：为探明扬水曝气诱导自然混合对深水分层型水库水质持续改善效果,对李家河水库水质进行为期一年的连续监测,对比不同运行条件下人工诱导混合期及持续自然混合期同期水质变化,采用综合污染指数对水质改善效果进行评价并采用相关性分析得出持续自然混合期间水质改善机制.结果表明:①人工强制混合可破坏水体热分层结构,缩小垂向温差,当平均气温低于表层水温时,诱导水体提前进入完全混合状态,延长混合周期2~3个月.②相较于自然过程,在诱导混合作用下持续自然混合期水体混合周期被延长,水体水质可得到持续改善:总氮、硝氮、氨、总磷均值浓度呈持续下降趋势,削减率分别为16.67%、11.94%、46.90%和35.1%,WQI指数>70的时间为139 d.同时,在人工强制(诱导)混合与持续自然混合衔接良好的运行条件下,水体维持完全混合状态更久,水质持续改善效果更好,总氮、硝氮、氨、总磷均值浓度削减率分别提升到20.69%、26.97%、60.00%和57.87%.氨与总磷均可满足地表Ⅱ类水标准,水质评价为良好,WQI指数>70的时间延长为165 d.③溶解氧浓度与参与氮循环的功能微生物Bacillus和Rhodococcus呈显著正相关关系.扬水曝气诱导自然混合可通过改善水体环境,增强水体混合程度,维持较高的溶解氧水平,强化好氧反硝化微生物作用从而达到改善水质、保障供水安全的目的.To assess the continuous improvement effect of water quality induced by water aeration in Li Jiahe reservoir,a one-year continuous monitoring was conducted.The study compared the water quality under different operating conditions that induce mixing with the natural mixing period.The comprehensive pollution index was used to evaluate the water quality improvement effect,and correlation analysis was employed to investigate the water quality improvement mechanism during continuous natural mixing.The results indicated that artificial forced mixing disrupts the thermal stratification structure of water,diminishing the vertical temperature difference.This process advances the water to a fully mixed state earlier when the average temperature is lower than the surface water temperature,extending the mixing cycle by 2~3 months.Moreover,compared to the natural process,the mixing cycle during continuous natural mixing under artificial induced mixing was prolonged,leading to continuous improvement in water quality.The mean concentrations of total nitrogen,nitrogenous nitrogen,ammonia,and total phosphorus demonstrated a continuous decrease,with reduction rates of 16.67%,11.94%,46.90%,and 35.1%,respectively.The days with"WQI index>70"increased to 139 days.Under both artificial forced mixing and continuous natural mixing conditions,the water remained fully mixed for an extended period,resulting in better water quality.The reduction rates of the mean concentrations of total nitrogen,nitrogenous nitrogen,ammonia,and total phosphorus increased to 20.69%,26.97%,60.00%,and 57.87%,respectively.The ammonia and total phosphorus levels met surface water standards,leading to an evaluation of good water quality and an extension of the days with"WQI index>70"to 165 days.Furthermore,there was a strong positive correlation between dissolved oxygen concentration and Bacillus and Rhodococcus,the functional microorganisms involved in the nitrogen cycle.The natural mixing induced by water aeration enhances the water environment,elevates the wate

关 键 词：深水分层型水库 诱导混合 持续自然混合 扬水曝气 水质改善效果评价 

分 类 号：X524[环境科学与工程—环境工程] X824