Study on Low Carbon-to-Nitrogen Municipal Wastewater Using Pre-Denitrification Biological Filter

摘要

the performance of pre-denitrification biological aerated filter in a pilot-scale, especially enhancing denitrificaion methods for low carbon-to-nitrogen domestic sewage, was assessed using all reflux to denitrification stage (DN) and shunting circuit into settling bucket and DN. The results showed that in the condition of all reflux to DN ,at the reflux ratio ranges from 100 ,130 to 150%, the average removal efficiency of TCOD enhanced with the value 58.5, 62.3 and 65.8% and that of NH4-N was 84.5,87.5 and 94.7%, whereas the average removal efficiency of TN presented 37.1, 40.9 and 39.7%. In the test, the removal increase of total nitrogen had no unanimous increase with the reflux ratio increase. The TN average removal achieved 56.4% and 60.5% when the quantities of reflux were shunted circuit to settling bucket and DN by 1:1 and 2:1 at 130% of the return flow. Therefore, most of reflux passing by settling bucket for oxygen consumption was the better proposal of improving TN removal efficiency for low C/N wastewater.