Denitrification of groundwater by a combined reactor of heterotrophication, electrolysis and biofilm

摘要

The denitrification process for groundwater with a heterotrophication-electrode-biofilm combination reactor (HEBCR) was investigated in this paper. The process was dependent primarily on heterotrophic denitrification. Residual methanol, nitrate, or nitrite was removed in the electrochemical section. There was no nitrite accumulation or residual methanol in the effluent when the feed C:N ratio (n/m) varied from 2.2 to 2.9. However, slightly excessive methanol could increase the treatment capacity of the reactor. Maximum denitrification load at 24 °C was 10.68g NO_3~-/m~3·h (47g NO_3~-) when the C:N ratio was 2.5-2.6 (mg/mg) and the feed nitrate-N concentration was 40mg/L.