海洋厌氧氨氧化菌的富集培养及其脱氮特性

Enrichment and Nitrogen Removal Characteristics of Marine Anaerobic Ammonium Oxidizing Bacteria

采用ASBR厌氧氨氧化反应器,通过接种胶州湾底泥,研究了海洋厌氧氨氧菌的富集培养及其脱氮特性.实验结果表明:海洋厌氧氨氧化菌的富集培养可分为4个阶段:菌体自溶期(1~15 d)、迟滞期(16~152 d)、活性提高期(153~183 d)与稳定运行期(184~192 d).与淡水厌氧氨氧化相比,其迟滞期(137 d)较长,活性提高期(30 d)较短,对基质浓度与HRT的变化更敏感,且由进出水导致的菌活性延迟时间为5 h,远长于淡水厌氧氨氧化菌,因此海洋厌氧氨氧化菌对新环境的适应能力更弱,更难富集培养.经过192 d运行,对NH_4^+-N与NO-2-N的去除率分别达到96.98%与95.66%,三氮转化比n(NH_4^+-N)∶n(NO-2-N)∶n(NO-3-N)为1∶(1.2±0.2)∶(0.22±0.06),接近理论比(1∶1.32∶0.26),NRRNH_4^+-N升至0.080 kg·(m^3·d)-1,海洋厌氧氨氧化菌活性显著提高,这标志着海洋厌氧氨氧化菌富集成功.反应器运行过程中,污泥逐渐由黑色泥状变为砖红色颗粒状,扫描电镜观察,该砖红色颗粒为表面光滑,排列紧密、有类似火山口形状的球状菌相互黏聚而成的菌团.

In this work, enrichment and nitrogen removal characteristics of marine anaerobic ammonium oxidizing bacteria were investigated by seeding sediment sludge from the Jiaozhou bay. Experimental results showed that the whole process could be divided into four phases：bacterial lysis phase （1-15 d）, lag phase （16-152 d）, exponential growth phase （153-183 d） and stationary phase （184-192 d）. Compared to freshwater anaerobic ammonium oxidizing bacteria, the lag phase （137 d） was longer. However, the exponential growth phase （30 d） was shorter. Besides, marine anaerobic ammonium oxidizing bacteria were more sensitive to variation in substrate concentration and HRT. The activity delay time caused by inflow and effluent was 5 h, which was far longer than fresh anaerobic ammonium oxidizing bacteria. As a result, the adaptive ability of marine anaerobic ammonium oxidizing bacteria was weaker and it was harder to enrich. After successful enrichment of 192 d, the removal rates of ammonia nitrogen and nitrite nitrogen were 96.98% and 95.66%, respectively. n（NH4＋-N）：n（NO2--N）：n（NO3--N） was 1：（1.2±0.2）：（0.22±0.06）, which was close to the theoretical ratio. NRRNH4＋-Nwas 0.080 kg·（m3·d）-1, which indicated that the activity of marine anaerobic ammonium oxidizing bacteria increased significantly. The enrichment of marine anaerobic ammonium oxidizing bacteria was achieved. The sludge characteristics changed from black to red. SEM observation confirmed that the red granule was cenobium, which consisted of closely spaced micrococcus with smooth surface and crateriform shape.