Integrating biological ion exchange with biological activated carbon treatment for drinking water: A novel approach for NOM removal, trihalomethane formation potential, and biological stability

Yun Lee; Jin-Hyung Noh; Ji-Won Park; Seon-Won Yoon; Sang-Yeob Kim; Hee Jong Son; Woorim Lee; Sung Kyu Maeng

doi:10.1016/j.watres.2023.120598

Integrating biological ion exchange with biological activated carbon treatment for drinking water: A novel approach for NOM removal, trihalomethane formation potential, and biological stability

Water Res. 2023 Oct 15:245:120598. doi: 10.1016/j.watres.2023.120598. Epub 2023 Sep 9.

Authors

Yun Lee¹, Jin-Hyung Noh¹, Ji-Won Park¹, Seon-Won Yoon¹, Sang-Yeob Kim¹, Hee Jong Son², Woorim Lee², Sung Kyu Maeng³

Affiliations

¹ Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea.
² Busan Water Quality Institute, Busan Water Authority, Busan 50804, Republic of Korea.
³ Department of Civil and Environmental Engineering, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Republic of Korea. Electronic address: smaeng@sejong.ac.kr.

PMID: 37722140
DOI: 10.1016/j.watres.2023.120598

Abstract

Ion exchange resins (IEX) are used in drinking water utilities to remove natural organic matter (NOM) from surface water; however, the disposal of used brine can be a major drawback. Recently, biological ion exchange (BIEX) has been proposed as an alternative to biological activated carbon (BAC) for removing natural organic matter (NOM). The present study is, to the best of our knowledge, the first attempt to use a hybrid BIEX and BAC (BIEX+BAC) system for drinking water treatment. The removal of NOM, assimilable organic carbon, and trihalomethane formation potential was investigated by operating four columns comprising IEX, BIEX, BAC, and BIEX+BAC with 18,000 bed volumes. The BIEX+BAC system was the most effective at removing dissolved organic carbon (59.9%). Based on fluorescence excitation-emission matrix spectroscopy, the BIEX+BAC column showed the maximum removal rates in all peak regions of T1, T2, and A. Using liquid chromatography-organic carbon detection, resin-containing columns were found to effectively remove humic substances, which are the principal precursors of trihalomethanes. The lowest potential for trihalomethane formation was observed in BIEX+BAC. BIEX+BAC also had the highest assimilable organic carbon removal efficiency (61.2%) followed by BIEX (52.3%), BAC (49.5%), and IEX (47.1%). The BIEX+BAC hybrid was found to be the most effective method for removing NOM fractions and reducing the formation of disinfection byproducts.

Keywords: Biological ion exchange; Biological stability; Ion exchange; Natural organic matter; Trihalomethane formation potential.