双循环两相生物处理工艺除磷试验

采用双循环两相生物脱氮除磷工艺（BICT）进行除磷试验研究。双循环两相生物脱氮除磷工艺由独立设置的前置厌氧反应器、悬浮生长的主反应器、附着生长的硝化反应器及介于主反应器和硝化反应器之间的沉淀池组成。在改变四种运行参数（泥龄、充水比、上清液回流比、运行时序）的条件下，对双循环两相生物处理工艺的除磷能力进行了实验室规模的试验研究。试验用反应器总体积为70L，连续运行210d。试验原水为市政污水。结果表明：BICT工艺通过缩短主反应区的运行泥龄，在不降低系统脱氮效率的基础上，强化了系统的除磷能力。当泥龄从20d降低至5d时，系统的除磷效率由76．5％提高至89．3％。缩短泥龄使主反应区的充水比得以提高，容积利用率增加；充水比可由最初的33％增加至60％。硝化液回流比由100％提高到200％时，系统的除磷效率几乎没有变化，这说明硝化液回流比对系统除磷能力影响较小；在循环周期中增加后曝气可进一步提高系统的过剩摄磷能力。

PHOSPHORUS REMOVAL BY BI-CYCLIC TWO-PHASE(BICT) PROCESS

A lab-scale BICT biological nutrient removal process was used for a phosphorus removal.It consists of an attached-growth reactor for growing autotrophic nitrifying bacteria,a suspended-growth sequencing batch reactor for growing heterotrophic organisms,a prepositive anaerobic biological reactor and a clarifier between suspended-growth sequencing batch reactor and attached-growth reactor.In this research,the capability and efficiency of phosphorus removal of BICT process were investigated under the conditions of altering four major operation parameters,such as sludge age,ratio of water-filling,the reflux ratio of supernatant.The results showed that,through shortening operational sludge age in main reaction area,the BICT thechnological process enhanced phosphorus removal ability in the system based on not lowering nitrogen removal efficiency.When sludge age lowered from 20d to 5d,the system's phosphorus removal effieieney was raised to 89.3% from 76.5%.