This study focuses on anaerobic ammonium oxidation (anammox) treatment performance for nitrogen removal using malt ceramics (MC) as a biomass carrier. A fixed-bed reactor using MC material with 3 to 5 mm diameter pieces (Reactor 1) was operated for 368 days and another using MC material with 10 to 15 mm diameter pieces (Reactor 2) was operated for 280 days. For Reactor 1, with an HRT of 3 h, the influent concentrations of NH
4-N and NO
2-N were both increased stepwise from 150 mg N/
l to 225 mg N/
l with NH
4-N removal efficiency of about 81% and NO
2-N removal efficiency of 90%. Then, the influent concentrations of NH
4-N and NO
2-N were increased to 250~275 mg N/
l, each, and removal efficiencies of NH
4-N and NO
2-N decreased to 75% and 85%, respectively. The T-N removal rates of Reactor 1 increased stepwise from 0.6 to 3.1 kg N/m
3/day from day 187 to day 315. Ratios of T-N removal, NO
2-N removal, and NO
3-N production to NH
4-N removal for Reactor 1 were 1.98:1.15:0.17, respectively. For Reactor 2, with an HRT of 3 h, the influent concentrations of NH
4-N and NO
2-N were both increased stepwise from 100 mg N/
l to 225 mg N/
l and removal efficiencies of NH
4-N and NO
2-N were high at 80% and 93%, respectively. However, when the influent concentrations of NH
4-N and NO
2-N were increased to 250~275 mg N/
l, each, removal efficiencies of NH
4-N and NO
2-N decreased to 72% and 84%, respectively. The T-N removal rates of Reactor 2 were similar to those of Reactor 1 with 0.7 to 3.1 kg N/m
3/day from the day 146 to day 230. Ratios of T-N removal, NO
2-N removal, and NO
3-N production to NH
4-N removal for Reactor 2 were 2.03:1.2:0.17, respectively. In addition, distinctive red granular anammox biomass grew at the bottom parts of the reactors during both runs. By DNA analyses, both KSU-1 and KU-2 strains were detected in anammox sludge of Reactor 2, with the KSU-1 strain being dominant.
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