TY - JOUR
T1 - Nitrogen transformation in slightly polluted surface water by a novel biofilm reactor
T2 - Long-term performance and microbial population characteristics
AU - Xia, Yinfeng
AU - Zhu, Lifang
AU - Geng, Nan
AU - Lu, Debao
AU - Xu, Cundong
AU - Withana, Piumi Amasha
AU - Vithanage, Meththika
AU - Khan, Eakalak
AU - Ok, Yong Sik
N1 - Funding Information:
The work was sponsored by the National Natural Science Foundation of China (No. 22006138 ), Zhejiang Provincial Natural Science Foundation of China (Nos. LQ18E090002 , LHY19E090003 , LZJWD22E090001 ), Zhejiang Public Welfare Technology Application Research Project (No. LGF21D020002 ). Y.S.O. was supported through a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (no. 2021R1A2C2011734 ), and was partly supported by the OJEong Resilience Institute (OJERI) Research Grant from the OJERI, Korea University, Republic of Korea.
Publisher Copyright:
© 2022
PY - 2022/7/10
Y1 - 2022/7/10
N2 - This study proposes a modular floating biofilm reactor (MFBR) for in situ nitrogen removal from slightly polluted water in rivers using enriched indigenous microorganisms. Its main structure is a 60 cm × 60 cm × 90 cm rectangular reactor filled with hackettens. After a 96-day startup, the removal efficiencies of ammonia-N and total N (TN) reached 80% and 25%, respectively, with a hydraulic retention time (HRT) of 10 h, whereas those in a control reactor (without biofilm) were only 4.9% and 0.2%, respectively. The influences of HRT and dissolved oxygen (DO) were also investigated. As a key factor, HRT significantly affected the removal efficiencies of ammonia-N and TN. When HRT was close to the actual value for a river studied (2.4 min), the removal efficiencies of ammonia-N and TN were only 8.7% and 3.1%, respectively. Aeration increased the concentration of DO in water, which enhanced nitrification but inhibited denitrification. When HRT was 2.4 min, aeration intensity was 20 L/min; the ammonia-N and TN removal rates were 9.5 g/(m2·d) and 11.3 g/(m2·d), respectively. The results of microbial community analysis indicated that the microorganisms forming the biofilm were indigenous bacteria. The findings demonstrated a concept-proof of MFBR, which may be evaluated in scaling up investigation for developing a new methodology for nitrogen removal from slightly polluted surface water in plain river networks.
AB - This study proposes a modular floating biofilm reactor (MFBR) for in situ nitrogen removal from slightly polluted water in rivers using enriched indigenous microorganisms. Its main structure is a 60 cm × 60 cm × 90 cm rectangular reactor filled with hackettens. After a 96-day startup, the removal efficiencies of ammonia-N and total N (TN) reached 80% and 25%, respectively, with a hydraulic retention time (HRT) of 10 h, whereas those in a control reactor (without biofilm) were only 4.9% and 0.2%, respectively. The influences of HRT and dissolved oxygen (DO) were also investigated. As a key factor, HRT significantly affected the removal efficiencies of ammonia-N and TN. When HRT was close to the actual value for a river studied (2.4 min), the removal efficiencies of ammonia-N and TN were only 8.7% and 3.1%, respectively. Aeration increased the concentration of DO in water, which enhanced nitrification but inhibited denitrification. When HRT was 2.4 min, aeration intensity was 20 L/min; the ammonia-N and TN removal rates were 9.5 g/(m2·d) and 11.3 g/(m2·d), respectively. The results of microbial community analysis indicated that the microorganisms forming the biofilm were indigenous bacteria. The findings demonstrated a concept-proof of MFBR, which may be evaluated in scaling up investigation for developing a new methodology for nitrogen removal from slightly polluted surface water in plain river networks.
KW - Biofilm reactor
KW - Denitrification
KW - Eutrophication
KW - Nitrification
KW - Surface water
UR - http://www.scopus.com/inward/record.url?scp=85126890518&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2022.154623
DO - 10.1016/j.scitotenv.2022.154623
M3 - Article
C2 - 35307444
AN - SCOPUS:85126890518
SN - 0048-9697
VL - 829
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 154623
ER -