O/A两级生物砂滤池的二次启动及其脱氮除碳效果

以城市二级处理出水为试验原水,通过逐渐提高滤速的方式,对停止运行近5个月的O/A两级生物砂滤池进行重新启动。重点研究了反应器的二次启动速度和启动后的脱氮除碳效果,以及C/N比对该工艺脱氮除碳效果的影响。试验结果表明,石英砂表面的生物膜并未死亡,通水运行后能在很短的时间内恢复正常。稳定运行期间,系统对CODCr和NH4+-N的平均去除率分别为45.53%和65.50%,出水CODCr和NH4+-N的平均浓度分别为48.50mg/L和4.12mg/L。当C/N比为5.0时,O/A两级生物砂滤池具有较高的TN脱除效果,TN去除率可达到30%以上,滤池出水TN含量低于15mg/L,均能达到一级A标准的要求。

Secondary start-up of O/A biological sand filters and its removal effect of nitrogen and carbon

Effluent of municipal secondary treatment was chosen as raw water to re-start up the O/A biological sand filters which stopped running nearly five months, in the way of increasing hydraulic load gradually. The secondary start-up speed, the removal effect of nitrogen and carbon, the influence of C/N ratio on removal effect of nitrogen and carbon were mainly studied. The results showed that the membrane attached on the surface of quartz sand is not dead, the O/A biological sand filters can back to normal run in a very short time. During stable operation, the average removal of CODCr and NH4+-N were 45.53% and 65.50% respectively, and the average concentration of CODCr and NH4+-N in effluent were 48.50mg/L and 4.12mg/L respectively. The removal efficiency of O/A biological sand filters is high for total nitrogen when the C/N ratio is 5.0; the removal rate of total nitrogen reaches above 30%, the average concentration of TN in effluent is lower than 15 mg/L. The effluent quality met the first A class standard of "urban sewage treatment plant pollutant discharge standard" (GB18918-2002).