Fig. 1.

Influent and effluent DOC concentrations of the three BAC filters during two-time periods: I. summer period since May 2016 for 110 days (Day 0–Day 110) and II. winter period since December 2016 for 42 days (Day 215–Day 255). Arrows indicate the backwashing at Day 96 and changing of flow rates at Day 215, respectively