Simultaneous Bromate and Nitrate Reduction in Water Using Sulfur-Utilizing Autotrophic and Mixotrophic Denitrification Processes in a Fixed Bed Column Reactor

DEMİREL S., UYANIK I., Yurtsever A., Celikten H., Ucar D.

CLEAN-SOIL AIR WATER, cilt.42, sa.9, ss.1185-1189, 2014 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 42 Sayı: 9
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1002/clen.201300475
  • Dergi Adı: CLEAN-SOIL AIR WATER
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1185-1189
  • Erciyes Üniversitesi Adresli: Evet

Özet

Carcinogenic bromate (BrO3-) can be present in drinking water as a result of its formation from bromide (Br-) during ozonation. A fixed bed column reactor filled with elementel sulfur and limestone was operated for about six months under autotrophic and mixotrophic (autotrophic+heterotrophic) conditions at 30 degrees C. The reactor was operated at the hydraulic retention time (HRT) ranging from 16.5 to 10.1h at autotrophic conditions. Under mixotrophic conditions, 45mg/L NO3-N was removed completely at C/N ratio (mg CH3OH/mg NO3-N) between 0.55 and 1.66 at HRT of 10.1h. The average effluent pH was 7.8 and the sulfate concentration was lower than the Environmental Protection Agency limits at the mixotrophic stages. Efficient simultaneous BrO3- and nitrate removal was achieved at feed concentrations of 100-500 mu g/L BrO3- and 45mg/L nitrate under autotrophic and mixotrophic conditions. Effluent Br- measurements indicated that BrO3- was completely reduced without accumulation of by-products.

Carcinogenic bromate (BrO-3) can be present in drinking water as a result of its formation from bromide (Br-) during ozonation. A fixed bed column reactor filled with elementel sulfur and limestone was operated for about 6 months under autotrophic and mixotrophic (autotrophic+heterotrophic) conditions at 30oC.  The reactor was operated at the hydraulic retention time (HRT) ranging from 16.5 to 10.1 h at autotrophic conditions. Under mixotrophic conditions, 45 mgL-1 NO3-N was removed completely at C:N ratio (mg CH3OH:mg NO3-N) between 0.55 and 1.66 at HRT of 10.1 h. The average effluent pH was 7.8 and the sulfate concentration was lower than the Environmental Protection Agency (EPA) limits at the mixotrophic stages. Efficient simultaneous bromate and nitrate removal was achieved at feed concentrations of 100-500 µgL-1 bromate and 45 mgL-1 nitrate under autotrophic and mixotrophic conditions. Effluent bromide measurements indicated that bromate was completely reduced without accumulation of by-products.