b.前置反硝化工艺 PTeanoxic Aerobic The first concept of a preanoxic BNR was an anoxic -aerobic operating uence by Ludzock ond Etinger(1962). The influent wastewater was ho an anoxic zone, which wos followed by an aerobic zone. The process reies on the nitrate formed in the aerobic zone being returned via the RAS to the anoxic zone. Because the only nitrate fed to the anoxic zone is that in the rAs, denitrification is limited greatly by the RAS recycle noto. However, more recently, this process has been used le rates to prevent rising sludge in the dary darifiers due to deni MLE工艺【(AO)生物脱氪工艺】 缺氧段同样位于樂统前面,从曝气池末端回流含有大 量硝酸盐的混合漩,在缺氧池中进行反硝化脱氪,反 硝化反应以原污水中的有机物为碳源,这是目前通称 的缺氧好氧(AO)反硝化生物脱氮工艺 内循环(硝化液回流) 沉淀池 原废水 处理水 (好氧) 缺氧) 回流污泥 剩余污泥 图18-6缺氧一好氧生物脱氮工艺12 b. 前置反硝化工艺 缺氧段同样位于系统前面，从曝气池末端回流含有大 量硝酸盐的混合液，在缺氧池中进行反硝化脱氮，反 硝化反应以原污水中的有机物为碳源，这是目前通称 的缺氧好氧（AO）反硝化生物脱氮工艺。 MLE工艺【（AO）生物脱氮工艺 】：