Abstract:

High salinity ammonia nitrogen wastewater generated in industry has a greater inhibitory effect on biological denitrification. Aerobic granular sludge technology can be used to effectively treat the wastewater. However， most of SBR are one-feeding and single-aeration processes， which have insufficient carbon source and anaerobic time in the subsequent operation， making nitrogen removal performance limited. The enhanced denitrification effect of aerobic granular sludge system for high salinity ammonia nitrogen wastewater was investigated by varying operating process with step-feeding and intermittent aeration conditions. The salinity tolerance performance of the system and effect of the process on sludge biomass and particle stability were evaluated， along with a mechanistic explanation of partial nitrification. The results showed that when influent salinity was 1% and mass concentration of ammonia nitrogen was 100 mg/L and 200 mg/L， the removal rates of total nitrogen by step-feeding and intermittent aeration processes were （82.51±5.66）% and （76.25±2.42）%， respectively， and the partial nitrification rates reached （89.62±11.26）% and （92.40±3.88）%， respectively. The results of cycle experiments showed that the supplemental carbon source， additional anaerobic process and occurrence of partial nitrification were important reasons for the increase of total nitrogen removal rate. Throughout the experiment， the system maintained high biomass and good particle settling performance. The setting of amine feast period under step-feeding and intermittent aeration conditions promoted the granulation of sludge with plump and rounder particle appearance， and increased average density， settling velocity and particle size， which was beneficial for microorganisms to cope with salinity stress， thus enhancing denitrification performance. Nitrification kinetics experiments showed that the setting of aeration duration under intermittent aeration conditions may be the main reason for the partial nitrification.

Key words: aerobic granular sludge, high salinity ammonium nitrogen wastewater, intermittent aeration, partial nitrification

摘要：

工业领域产生的高盐氨氮废水对生物脱氮有较大的抑制作用。采用好氧颗粒污泥技术可有效处理此类废水。但常见的序批式反应器大都为一次进水、单段曝气工艺，运行后期碳源和厌氧时长不足，使得脱氮性能受到限制。通过改变运行工艺，探讨分段进水、间歇曝气条件下，好氧颗粒污泥系统对高盐氨氮废水的强化脱氮效果，评价系统耐盐性能，以及该工艺对污泥生物量和颗粒稳定性的影响，同时对短程硝化现象进行机理解释。结果表明，当进水盐度为1%、氨氮质量浓度分别为100、200 mg/L时，分段进水、间歇曝气工艺对总氮的去除率分别为（82.51±5.66）%、（76.25±2.42）%，短程硝化率分别达到（89.62±11.26）%、（92.40±3.88）%。周期实验结果表明，补充碳源、增设厌氧段及短程硝化反应发生是总氮去除率提升的重要原因。在整个实验过程中，系统保持较高的生物量和良好的颗粒沉降性能。间歇曝气及分段进水条件下饥饿-丰盛期的设定促进了污泥颗粒化，颗粒外观更加饱满圆润，平均密度、沉速和粒径均增大，有利于微生物应对盐度胁迫，从而提升脱氮性能。硝化反应动力学实验表明，间歇曝气条件下曝气时长的设置可能是系统出现短程硝化现象的主要原因。

关键词: 好氧颗粒污泥, 高盐氨氮废水, 间歇曝气, 短程硝化

CLC Number: 

• X703

• TU992.3