Comparative study of nitrogen bioremoval from aquaculture wastewater using bioflocs technique (BFT) versus biofiltration system [electronic resource].

Includes references.

LaboratOlY experiment aimed to comparison between treatment offish
wastewater /Ising biofloc technology (8FT) and bioJilter system to re-use
water and reduce its change periods. Ammonium concentration
increased from 0.51 mg/I at beginning of experiment to 0.5-4 mg/I and
decreased to 0.25 mg/I and is .fixed at 0.49 mg/I for biofilter samples.
While, these concentrations ware 0.62- 0.87-0.12-0.27 mg/I for biofloc
treatment samples. Ammonium reduction ratio of biofilter was 32%
versus 17.33% for biofloc technique at beginning of experiment then it
still increasing and reached to 42 % for biofilter against 7.45% of
biofloc technique. Unexpected decrease in the ammonium reduction ratio
for biofilter system by 21.87 and 15.52% versus 62.50 and 53.45%
correspondingly for biofloc. These results were referred to biofiltration
process adaptation and lack of uniformity of bioflocs throughout whole
water tank. Results of measured ammonium concentrations show
superiority of the use of biofloc technique over bioJilter system. The
decline in nitrite reduction ratio for biofilter of 63.16% at the second
week of the start of experiment happened and then there was a slight
increase in nitrite reduction ratio 63.49% to be settled on the 65%
reduction ratio value. This was referred to biofilter clogging and
biomass accumulation. Biofloc technique demonstrated an excessive
superiority (93.02%) in nitrite reduction ratio at beginning of the
experiment over biofilter system (70.54%). Two systems had similar
behavior of nitrite reduction ratio throughollt the rest of experiment.
Finally, use of BFT systems to freshwater tilapia aquaculture benefits
both the reduction in ammonium and nitrite concentrations and can be
effective in improvementfish production.

Summary in Arabic.