降温方式对厌氧氨氧化脱氮性能的影响

考察一次性降温和阶梯式降温对厌氧氨氧化反应器(ASBR)脱氮性能的影响。一次性降温方式（30 ℃降至15 ℃），阶梯式降温方式（30 ℃降至25 ℃，再降至20 ℃，最后降至15 ℃）。温度30 ℃时，NH4+-N和NO2--N的去除率分别为97.3%和98.5%，总氮去除速率为5.12 mg·(g·h)-1，ΔNO2--N/ΔNH4+-N为1.33，厌氧氨氧化活性(SAA)为0.139 g·(g·d)-1。一次性降温至15 ℃时，NH4+-N和NO2--N的去除率分别降至47.9%和55.1%，总氮去除速率降至2.74 mg·(g·h)-1，ΔNO2--N/ΔNH4+-N升至1.51，SAA降至0.071 g·(g·d)-1。阶梯式降温至15 ℃时，NH4+-N和NO2--N的去除率降至51.6%和61.2%，总氮去除速率降至3.22 mg·(g·h)-1，ΔNO2--N/ΔNH4+-N升至1.48，SAA降为0.083 g·(g·d)-1。阶梯式降温方式脱氮性能更佳。

Effect of cooling methods on nitrogen removal performance of anammox

The denitrification performance of the anaerobic ammonia oxidation reactor (ASBR) under one time cooling and step cooling was compared and analyzed in this experience. One time cooling method (30 ℃ down to 15 ℃), step cooling method (30 ℃ down to 25 ℃, then decrease to 20 ℃,finally fall to 15 ℃). The removal rates of NH4+-N and NO2--N were 97.3% and 98.5%, respectively, and the specific nitrogen removal rate was 5.12 mg·(g·h)-1, and the ΔNO2--N/ΔNH4+-N was 1.33 and the specific anammox activity (SAA) was 0.139 g·(g·d)-1when the temperature was controlled at 30 ℃. The removal rates of NH4+-N and NO2--N reduced to 48.0% and 56.1%, respectively, and the specific nitrogen removal rate dropped to 2.74 mg·(g·h)-1, and the ΔNO2--N/ΔNH4+-N increased to 1.51 and SAA decreased to 0.071 g·(g·d)-1when the temperature was cooled one-time from 30 ℃ to 15 ℃ . However the removal rates of NH4+-N and NO2--N reduced to 51.6% and 61.2%, respectively, and the specific nitrogen removal rate dropped to 3.22 mg·(g·h)-1 , and the ΔNO2--N/ΔNH4+-N increased to 1.48 and SAA reduced to 0.083 g·(g·d)-1 when the temperature was cooled step by step to 15 ℃, which suggested that the nitrogen removal performance of step cooling method was superior to that of one-time cooling method.