Shortcut nitrification rates at different aeration and sludge retention time

A sequencing batch reactor was employed to treat high ammonia concentration wastewater and investigate the shortcut nitrification rates under different aeration and sludge retention time(SRT) conditions. During the start-up stage SRT and temperature were set at 12d and 30°C, respectively, and complete shortcut nitrification was achieved on 31d. The effect of aeration, SRT on ammonia oxidation rate, nitrite production rate,and nitrate production rate was studied under the 300mgNH4+-N/L, as SRT was kept at 12, 21, 30d and SRT with infinite time, and aeration at 0.14 and 0.18m3/h. The results showed that the optimal operational parameters were SRT = 12d, aeration at 0.18m3/h based on ammonia oxidation rate. The maximum ammonia oxidation rate was achieved and to be 43.6×10-3·mgNH4+-N·h-1·mgMLSS-1under this condition, with 89% of nitrite accumulation rate.