RESUMO
To resolve the shortage of carbon source during traditional denitrification used to treat secondary effluent of acrylic fiber wastewater, tri-stage biofilm reactor was used, the influence of pH of influent, HRT, and NH4(+) -N concentration in raw water on NH4(+) -N removal was investigated. Efficiency of TN removal was also investigated. It demonstrated that the optimal HRT and pH were 24 hours and 7.8-8.0 respectively. Under these conditions the removal efficiencies of NH4(+) -N and TN were 94. 6% and 53% respectively. And the removal efficiency of NH4(+) -N had no relationship with the concentration of the inflow water. With absence of organic carbon source in the reactor, efficiency of TN removal was obvious, the average and the highest removal efficiencies of TN were 53% and 66% respectively, efficiency of secondary effluent of acrylic fiber wastewater nitrogen removal was obvious when treated with Tri-stage biofilm reactor.
