Summary
In order to apply magnetic force for biological wastewater treatment, method for production of magnetic immobilized cell bead was studied. In addition, magnetic bead column reactor(MBCR) with fixed bed mode was employed to investigate the process performance on denitrification process. According to the results of batch and semi-continuous operations, the appropriate magnetite (Fe3O4) content of the bead was 2.0 % (w/v), providing high specific gravity, high permeability and low floating ratio. MBCR achieved 99.5 to 100 % of nitrate removal with nitrate removal rate (NRR) of 14.49 to 43.1 mg N/l/hr at low/moderate nitrate loading of 14.49 to 43.40 mg N/l/hr. At high nitrate loading rates of 93.2 and 162.0mg N/l/hr, MBCR provided 80.1 and 67.8 % of nitrate removals with rates of 74.8 and 110.5 mg N/l/hr of NRR, respectively. Regarding the reactor design of MBCR with fixed bed mode, area nitrogen loading rate (ANLR, mg N/cm2 area/hr) appeared to be an important factor. The relation between ANLR and NRR were Y=31.092ln(X)+234.8.HomePageKeywords: magnetic bead, magnetic bead column reactor, denitrification, nitrite accumulation