Effect of conversion of internal carbon source on denitrifying phosphorus removal under different reaction time
ZHANG Jian-hua, WANG Shu-ying, ZHANG Miao, WANG Cong, PENG Yong-zhen
National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, China
Denitrifying polyphosphate accumulating organisms (DPAOs) could remove N and P simultaneously when exposed to sequential anaerobic-anoxic conditions. The key factor of denitrifying phosphorus removal by DPAOs was the conversion and utilization of internal carbon source. To evaluate the effect of conversion and utilization of internal carbon source on the removal of nitrogen and phosphorus, batch experiments were conducted with different anaerobic/anoxic reaction time using denitrifying phosphorus activated sludge taken from an anaerobic/anoxic/oxic (A2/O)-biological contact oxidation (BCO) system. The results showed that DPAOs produced the highest amount of poly-β-hydroxyalkanoate (PHA) and finished phosphorus release when anaerobic reaction time was 90min, while too long anaerobic reaction time (120, 150min) led to the decrease of PHA and affected denitrifying phosphorus removal. Additionally, the effect of long anaerobic reaction time on phosphorus absorption was more significant than that on denitrification by NO3--N, and the specific phosphorus uptake rate suffered a 30 percent fall when extending the anaerobic reaction time to 150min. Under the appropriate anaerobic conditions, the optimal anoxic reaction time for nitrogen and phosphorus removal was 120min. The nitrogen and phosphorus removal couldn't finish with a short reaction time (60min), while Gly was partially degraded with long anoxic reaction time (180, 240, 300min), denitrifying phosphorus removal was indirectly affected, and it was of no advantage to the long-term operation. Furthermore, in a short time, the impact of long anaerobic reaction time on the nitrogen and phosphorus removal was greater than that of long anoxic reaction time.
Kuba T, Smolders G, Vanloosdrecht M C M, et al. Biological phosphorus removal from waste-water by anaerobic-anoxic sequencing batch reactor [J]. Water Science and Technology, 1993,27(5/6):241-252.
[2]
Kong Y H, Nielsen J L, Nielsen P H. Microautoradiographic study of Rhodocyclus-related polyphosphate accumulating bacteria in full-scale enhanced biological phosphorus removal plants [J]. Applied and Environmental Microbiology, 2004,70(9): 5383-5390.
[3]
Tsuneda S, Ohno T, Soejima K, et al. Simultaneous nitrogen and phosphorus removal using denitrifying phosphate-accumulating organisms in a sequencing batch reactor [J]. Biochemical Engineering Journal, 2006,27(3):191-196.
[4]
Zeng R J, Lemaire R, Yuan Z, et al. Simultaneous nitrification, denitrification, and phosphorus removal in a lab-scale sequencing batch reactor [J]. Biotechnology and Bioengineering, 2003,84(2): 170-178.
[5]
Tsuneda S, Miyauchi R, Ohno T, et al. Characterization of denitrifying polyphosphate-accumulating organisms in activated sludge based on nitrite reductase gene [J]. Journal of Bioscience and Bioengineering, 2005,99(4):403-407.
Zhang S H, Huang Y, Hua Y M. Denitrifying dephosphatation over nitrite: Effects of nitrite concentration, organic carbon, and pH [J]. Bioresource Technology, 2010,101(11):3870-3875.
Zhou S Q, Zhang X J, Feng L Y. Effect of different types of electron acceptors on the anoxic phosphorus uptake activity of denitrifying phosphorus removing bacteria [J]. Bioresource Technology, 2010,101:1603-1610.
Wang Y Y, Peng Y Z, Stephenson T. Effect of influent nutrient ratios and hydraulic retention time (HRT) on simultaneous phosphorus and nitrogen removal in a two-sludge sequencing batch reactor process [J]. Bioresource Technology, 2009,100(14): 3506-3512.
Wachtmeister A, Kuba T, Van Loosdrecht M C M, et al. A sludge characterization assay for aerobic and denitrifying phosphorus removing sludge [J]. Water Research, 1997,31(3):471-478.
[16]
APHA. Standard Methods for the Examination of Water and Wastewater [M]. 14th ed. Washington DC: APHA American Public Health Association, 1976.
[17]
Oehmen A, Keller-Lehmann B, Zeng R J, et al. Optimisation of poly-beta-hydroxyalkanoate analysis using gas chromatography for enhanced biological phosphorus removal systems [J]. Journal of Chromatography A, 2005,1070(1/2):131-136.
Pijuan M, Casas C, Baeza J A. Polyhydroxyalk anoate synthesis using different carbon source by two enhanced biological phosphorus removal microbial communities [J]. Process Biochemistry, 2009,44(1):97-105.
Meinhold J, Filipe C D M, Daigger G T. Characterization of the denitrifying fraction of phosphate accumulating organisms in biological phosphate removal [J]. Water Science and Technology, 1999,39(1):31-42.
Soejima K, Oki K, Terada A, et al. Effects of acetate and nitrite addition on fraction of denitrifying phosphate-accumulating organisms and nutrient removal efficiency in anaerobic/aerobic/anoxic process [J]. Bioprocess and Biosystems Engineering, 2006, 29(5/6):305-313.
[28]
Wang Y Y, Geng J J, Ren Z J, et al. Effect of anaerobic reaction time on denitrifying phosphorus removal and N2O production [J]. Bioresource Technology, 2011,102(10):5674-5684.
Wang Y Y, Geng J J, Peng Y Z, et al. A comparison of endogenous processes during anaerobic starvation in anaerobic end sludge and aerobic end sludge from an anaerobic/anoxic/oxic sequencing batch reactor performing denitrifying phosphorus removal [J]. Bioresource Technology, 2012,104:19-27.
Bassin J P, Kleerebezem R, Dezotti M, et al. Simultaneous nitrogen and phosphate removal in aerobic granular sludge reactors operated at different temperatures [J]. Water Research, 2012,33(10):3805-3816.
[34]
Lv X M, Shao M F, Li C L, et al. Operation performance and microbial community dynamics of phosphorus removal sludge with different electron acceptors [J]. Journal of Industrial Microbiology & Biotechnology, 2014,41(7):1099-1108.
