Author: Dilek Erdirençelebi, Evelina MİHAYLYAN
Publishing Date: 2015
Volume: 3 Issue: 3
Anaerobic reject water (ARW) treatment at pilot-scale sequential batch reactor (SBR) was conducted with 2 and 4-phase at mixed order for N, P and organic matter removal. Short-cut biological nitrogen removal (SBNR) process was implemented with partial nitrification and denitrification over nitrite. Bicarbonate and simple structure organic matter defiencies were determined as the two major limiting factors. Simultaneous organic matter oxidation with nitritation reduced theoratical alkalinity requirement whereas volatile fatty acids (VFA) produced did not promote denitritation. Phosphate was removed onyl via biosynthesis. VFA proved to be of complex structure and not amenable for facultative bacteria. In case of high VFA degradation anaerobic bacteria transported with ARW was believed to be efficient. Nitritation rates were competible with the reported values at 20 oC and increased with increasing ammonium loading rate. Sludge age was obtained at an optimum level for nitrification without control. Results showed that high temperature and low sludge age are not necessarily required for partial nitrification at SBR technology.
Key Words: Nitrogen, biological removal, SBR, anaerobic reject water, side-line treatment.