| 主流条件下两级式PN-ANAMMOX工艺的高效能脱氮过程 |
| 摘要点击 2166 全文点击 656 投稿时间：2018-04-26 修订日期：2018-05-20 |
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| 中文关键词 生物脱氮 部分亚硝化(PN) 厌氧氨氧化(ANAMMOX) 低温 市政污水 |
| 英文关键词 biological nitrogen removal partial nitritation (PN) ANAMMOX low temperature sewage |
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| 中文摘要 |
| 中低温条件下采用两级式PN-ANAMMOX工艺对低浓度NH4+-N（50 mg·L-1）污水进行高效脱氮过程研究.结果表明，20~14℃范围内PN-ANAMMOX工艺的脱氮负荷和TN去除率可分别维持在0.6 kg·（m3·d）-1和80%以上；两级式PN-ANAMMOX工艺在限NO2--N和限NH4+-N两种模式下均可保持稳定运行，其中限NH4+-N运行模式为污水极限脱氮需求奠定了良好基础.当温度降至12℃时，PN-ANAMMOX工艺的脱氮负荷下降至0.5 kg·（m3·d）-1左右，低温使得ANAMMOX反应成为工艺脱氮的限速步骤而对PN无明显影响.ANAMMOX污泥比PN颗粒污泥具有更高的温度敏感性，二者活性的温度系数分别为1.056和1.172.综上可知，对于低温条件下运行的两级式PN-ANAMMOX工艺，ANAMMOX菌体数量及活性是决定工艺脱氮负荷的步骤，而PN出水中基质组成（即NO2--N/NH4+-N之比和NO3--N浓度）是控制工艺脱氮效果的环节.基于上述结果，提出两级式PN-ANAMMOX工艺主流条件下实现高效能脱氮的分级分离式调控策略. |
| 英文摘要 |
| A two-stage partial nitritation (PN)-ANAMMOX process was successfully carried out for low-strength NH4+-N (50 mg·L-1) wastewater treatment at ambient/low temperatures. The results show that an average total nitrogen removal rate and removal efficiency above 0.6 kg·(m3·d)-1and 80% could be maintained, respectively, at temperatures between 20℃ and 14℃. The two-stage PN-ANAMMOX process was successful both under NO2--N-limited and NH4+-N-limited conditions. When the two-stage PN-ANAMMOX process was operated under NH4+-N-limited conditions, the "limit of technology" for nitrogen removal (TN<3 mg·L-1) could be easily achieved by following anoxic denitrification. Lowering the temperature to 12℃ resulted in the reduction of the total nitrogen removal rate to~0.5 kg·(m3·d)-1. Due to the low temperature, the anammox reaction became the rate-limiting step for nitrogen removal, while the PN reaction was not impacted. In the temperature range of 10-20℃, the activity-temperature coefficients (θ) of the PN granules and ANAMMOX sludge were 1.056 and 1.172, respectively, suggesting that the anammox bacteria have a higher temperature sensitivity than the ammonium oxidizing bacteria (AOB). Overall, the results clearly indicate that the nitrogen removal loading rate of the two-stage PN-ANAMMOX process is mainly controlled by the activity and quantity of anammox biomass. In contrast, the process nitrogen removal efficiency mainly depends on the performance of the first-stage PN (i.e., effluent NO2--N/NH4+-N ratio and NO3--N concentration) under a constant nitrogen removal loading rate (no overload). Based on these results, a hierarchically separate control strategy was proposed to obtain a high-rate nitrogen removal during the two-stage mainstream PN-ANAMMOX process. |
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