Jeong, Sanghyun Cho, Kyungjin Jeong, Dawoon Lee, Seockheon Leiknes, TorOve Vigneswaran, Saravanamuthu Bae, Hyokwan 2024-01-20T00:04:30Z 2024-01-20T00:04:30Z 2021-09-03 2017-11 0043-1354 https://pubs.kist.re.kr/handle/201004/122129 Four dual media filters (DMFs) were operated in a biofiltration mode with different engineered environments (DMF I and II: coagulation with/without acidification and DMF III and IV: without/with chlorination). Designed biofilm enrichment reactors (BERs) containing the removable reverse osmosis (RO) coupons, were connected at the end of the DMFs in parallel to analyze the biofilm on the RO membrane by DMF effluents. Filtration performances were evaluated in terms of dissolved organic carbon (DOC) and assimilable organic carbon (AOC). Organic foulants on the RO membrane were also quantified and fractionized. The bacterial community structures in liquid (seawater and effluent) and biofilm (DMF and RO) samples were analyzed using 454-pyrosequencing. The DMF IV fed with the chlorinated seawater demonstrated the highest reductions of DOC including LMW-N as well as AOC among the other DMFs. The DMF IV was also effective in reducing organic foulants on the RO membrane surface. The bacterial community structure was grouped according to the sample phase (i.e., liquid and biofilm samples), sampling location (i.e., DMF and RO samples), and chlorination (chlorinated and non chlorinated samples). In particular, the biofilm community in the DMF IV differed from the other DMF treatments, suggesting that chlorination exerted as stronger selective pressure than pH adjustment or coagulation on the biofilm community. In the DMF IV, several chemoorganotrophic chlorine-resistant biofilm-forming bacteria such as Hyphomonas, Erythrobacter, and Sphingomonas were predominant, and they may enhance organic carbon degradation efficiency. Diverse halophilic or halotolerant organic degraders were also found in other DMFs (i.e., DMF I, II, and III). Various kinds of dominant biofilmforming bacteria were also investigated in RO membrane samples; the results provided possible candidates that cause biofouling when DMF process is applied as the pretreatment option for the RO process. (C) 2017 Elsevier Ltd. All rights reserved. English Elsevier BV Effect of engineered environment on microbial community structure in biofilter and biofilm on reverse osmosis membrane Article 10.1016/j.watres.2017.07.064 1 Water Research, v.124, pp.227 - 237 Water Research 124 227 237 N scie scopus 000412251500022 2-s2.0-85026372162 Engineering, Environmental Environmental Sciences Water Resources Engineering Environmental Sciences & Ecology Water Resources Article DUAL-MEDIA FILTRATION SEAWATER DESALINATION GEN. NOV. DRINKING-WATER BACTERIAL COMMUNITIES SAND-FILTRATION ORGANIC-MATTER PRETREATMENT PLANT MICROFILTRATION Biofilm Biofiltration Chlorination Coagulation Seawater reverse osmosis Microbial community structure