LIU Qiang,WANG Tai,SHEN Bo,et al. Operation Effect of MBBR Applied in Upgrading and Reconstruction of a Wastewater Treatment Plant in Tianjin at Low Temperature [J].China Water & Wastewater,2020,36(13):7-13.
Operation Effect of MBBR Applied in Upgrading and Reconstruction of a Wastewater Treatment Plant in Tianjin at Low Temperature
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第36卷
Number:
13
Page:
7-13
Column:
Date of publication:
2020-07-01
- Keywords:
- MBBR; Bardenpho process; low temperature; high-throughput sequencing; upgrading and reconstruction
- Abstract:
-
A wastewater treatment plant (WWTP) in Tianjin was upgraded, and the effluent quality was required to meet the level A criteria specified in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (DB 12/599-2015)in Tianjin City. The biochemical unit was reconstructed in situ by applying moving bed biofilm reactor (MBBR) technology, in which the AAO process was changed into Bardenpho process. An additional anoxic zone was added to enhance the nitrogen removal efficiency of the biochemical system, and suspended carriers were added to the aerobic zone to ensure the ammonia nitrogen always meeting the standard. Advanced treatment technologies including air flotation, twostage ozonation, aerated activated carbon filter and V-type filter were adopted to ensure the TP, SS and COD always meeting the standard. At low temperature of 9-11 ℃ in winter, COD, BOD5, NH3-N, TN, TP and SS in the effluent of the WWTP were 24.52 mg/L, 0.88 mg/L, 0.29 mg/L, 6.82 mg/L, 0.08 mg/L and 2.32 mg/L, respectively, which steadily achieved the upgrading target. The suspended carrier had a good performance at low temperature, and the nitrification rate was 10 times that of the activated sludge, indicating that almost all the nitrification was completed by the suspended carrier. The design of Bardenpho process relieved the restriction of reflux ratio to TN removal, and the TN removal efficiency in the postanaerobic zone was 24.76%, indicating that the TN removal was enhanced and nitrogen in the effluent of the biochemical section reached the standard stably. The main nitrifying bacteria in the system were Nitrospira, which had a relative abundance of 13.14% on the suspended carrier in MBBR, but only 0.68% in activated sludge. The in-situ reconstruction of the biochemical section by MBBR process could effectively improve the nitrification capacity of the system, which
was an effective measure to cope with low temperature in winter and ensure the effluent quality to meet the standard.
Last Update:
2020-07-01