复合生物反应器低溶解氧同步脱氮除磷

利用复合生物反应器(HBR)中同时存在的活性污泥和悬浮生物膜混合生物体系,进行了同步脱氮除磷的试验研究.结果表明,溶解氧浓度和进水COD/TN对系统脱氮除磷效果有重要影响.当曝气量(Qair)控制在0.07m3/h时,系统的同步脱氮除磷效果较好,最大释磷率(释磷结束时溶液中PO3-4-P浓度与初始PO3-4-P浓度百分比)为249%,TN平均去除率为80.0%,PO3-4-P去除率为92.2%.曝气量升高或降低,TN、PO3-4-P去除率均降低.随着COD/TN的升高,系统TN、PO3-4-P去除率也逐渐升高,COD/TN从3.2升高至10.5,系统TN平均去除率从70.3%升高至84.9%,PO3-4-P平均去除率从82.2%高至96.0%.整个试验过程中污泥体积指数(SVI)均小于90 mL/g,污泥的沉降性能良好.实验采用复合反应器进水后未经过传统脱氮、除磷理论认为所必须的缺氧、厌氧段而直接曝气,仍然取得较高的TN、PO3-4-P去除率.

Simultaneous Nitrogen and Phosphorous Removal Under Low DO in a Hybrid Biological Reactor

Study was conducted by use of the mixed organism of activated sludge and suspended biofilm coexisting in a hybrid biological reactor (HBR) system for simultaneous nitrogen and phosphorous removal. The experimental results showed that, DO and COD/TN were the main factors affected the effluent , the maximum phosphorous releasing rate (the rate that PO43--P concentration at releasing end to the initial PO43--P concentration) was 249%, TN removal efficiency was 80.0%, PO43--P removal efficiency was 92.2% by controlling the aeration rate (Qair) at 0.07m3/h, TN and PO43--P removal efficiency will be decreased, whenever aeration rate increasing or decreasing. With the increasing of COD/TN, the TN and PO43--P removal efficiency was increased, TN removal efficiency was increased from 70.3% to 84.9% , PO43--P removal efficiency was increased from 82.2% to 96.0%, when COD/TN was increased from 3.2 to 10.5. The SVI of the activated sludg was less than 90ml/g during the experiments. It was found during the research process that high phosphorus and nitrogen removal efficiency can be simultaneous achieved without anaerobic and anoxic phase , which was conventionally considered as a key phase for phosphorus and nitrogen removal.