摘要
针对回流混合液中溶解氧导致缺氧池脱氮性能下降的问题,分析回流混合液中的溶解氧浓度及其对污水中易生物降解有机物的消耗量,提出设置脱气池的工程措施。在3座污水厂的现场试验表明,曝气停止后,混合液中溶解氧快速降低,30 min内混合液中溶解氧分别下降了1.24、2.78和1.86 mg/L。脱气池可以有效控制回流混合液中的溶解氧,平均去除溶解氧1.81 mg/L,耗氧速率为2.22 mgDO/(gVSS·h)。脱气池布置在好氧池的末端,内设搅拌器防止污泥沉降和利于脱气,设计水力停留时间(HRT)宜为0.5 h,可灵活应用于AAO和多级AO等工艺,提高污水处理厂的脱氮性能,可用于污水处理厂提标改造或新建工程中。
To solve the problem that dissolved oxygen in reflux mixed liquid leads to the decrease of denitrification efficiency in anoxic tank,the concentration of dissolved oxygen in the reflux mixed liquid and its consumption of biodegradable organic matter in wastewater were analyzed,and the engineering measure of setting up a deoxy tank was proposed.Field tests in three wastewater treatment plants showed that the dissolved oxygen in the mixed liquid decreased rapidly after the aeration stopped,and the dissolved oxygen decreased by 1.24 mg/L,2.78 mg/L and 1.86 mg/L within 30 min,respectively.The deoxy tank effectively controlled the dissolved oxygen in reflux mixed liquid with an average dissolved oxygen removal amount of 1.81 mg/L and an oxygen consumption rate of 2.22 mgDO/(gVSS·h).The deoxy tank was arranged at the end of the aerobic tank with a stirrer to prevent sludge settling and facilitate degassing.The designed hydraulic retention time(HRT)is suggested to be 0.5 h,which can be flexibly applied to AAO and multi-stage AO processes to improve the nitrogen removal performance of wastewater treatment plants,and it can be used in the upgrading of wastewater treatment plants or new projects.
作者
刘雷斌
高守有
李艺
LIU Lei-bin;GAO Shou-you;LI Yi(Beijing General Municipal Engineering Design&Research Institute Co.Ltd.,Beijing 100082,China)
出处
《中国给水排水》
CAS
CSCD
北大核心
2022年第16期52-56,共5页
China Water & Wastewater
基金
国家重点研发计划项目(2018YFC0406305)。
关键词
脱气池
溶解氧
回流混合液
deoxy tank
dissolved oxygen
reflux mixed liquid
