Study on Use of New Integrative Oxidation Ditch Process with Vertical Circulation for Urban Wastewater Treatment
tract:A new integrative oxidation ditch process with vertical circulation was developed with area of land occupation 50% less than the conventional oxidation ditch process.Smentation tank was built at one end,which had no effect on mixed liquor flow pattern in the ditch and achieved the automatic return of sludge.The unit was characterized by compact configuration and simple operation and maintenance.Expe riment was made by using domestic wastewater as influent with and TN concentration of 289~1147 mg/L and 65~87 mg/L respectively.The result showed that when HRT is 10 h and SRT is 30 d,the removal rate of ,BOD5,NH3-N and TN reaches 95%,98%,99%,and 91.2% respectively.
立体循环一体化氧化沟由转刷、上下两层沟道及沉淀区组成,其特点是: ① 化沟的上层为好氧区,下层为缺氧区,混合液在上下循环过程中完成降解有机 物和生物脱氮过程; ② 氧区在底层不与大气接触,缺氧环境形成快。与常规氧化沟相比,采取上下两层沟道立体循环方式减少占地面积约50%; ③ 淀区与氧化沟合建(建在氧化沟的一端),沉淀的污泥可自动回流到氧化沟内,无需污泥回流设备,节省了投资和能耗,并对氧化沟内混合液的流态无任何影响; ④ 构紧凑,运行操作简便。 立体循环一体化氧化沟结构形式如图1所示。
[1] Mandt G,Bell A.袁懋梓译.的氧化沟技术[M].北京:中国建筑工业出版社,19 88. [2] 刘俊新,王宝贞,Groenestijn van J W,et al.采用氧化沟从城市污水中去除氮和磷的研究[J].哈尔滨建筑大学学报,1997,30(5):36-40. [3] Liu J X,Groenestijn van J W,Doddema H J,et al.Influence of the aeration bru sh on nitrogen removal in the oxidation ditch[J].Eur Water Pollut Control,199 6,6(4):25-30.