不同纯生物菌剂对黑臭水体底泥的处理效果

目前黑臭水体底泥通常采用化学或生物方法进行异位治理,生物法由于简单易操作、处理成本较低而被广泛应用,并能够为后续的底泥资源化利用提供条件。为探究更适宜的生物处理方法,明确生物处理过程中的微生物群落变化规律,分别采用不同种类的纯生物菌剂(硝化细菌、反硝化细菌、光合细菌和芽孢杆菌)对黑臭水体底泥进行异位处理,通过投加不同剂量的纯菌剂,比较反应前后底泥中的总氮、总磷、有机质及含水率的变化。结果表明,在常温(20±5)℃下经过30 d的处理,底泥中含水率、总氮和有机质含量都有不同程度的降低。其中,投加量为35 mg/L的反硝化细菌试验组处理效果最好,总氮和有机质去除率分别达到59. 90%和20. 93%。三维荧光光谱分析表明,投加纯生物菌剂处理后,底泥中的大分子有机物浓度降低,小分子物质浓度有不同程度的升高,说明生物菌剂能够提高底泥中微生物的活性,不仅促进了有机物的降解,还为反硝化反应提供了碳源,促进了底泥中总氮的去除。此外,高通量测序也表明,投加菌剂的试验组样本中,都出现了一定丰度的Thiobacillus、Sulfurovum、Sulfuricurvum和Sulfurimonas,且在芽孢杆菌试验组和光合细菌试验组中比例较高,四个菌属总比例分别达到13. 24%和14. 80%。这四个菌属能够参与硫代谢,对于底泥中有机质(如蛋白等)的降解起到重要作用。

Treatment Efficiency of Black and Odorous Water Body Sediment with Different Biological Agents

At present,chemical or biological methods are usually employed for ectopic treatment of black and odorous water sediment. Biological method is widely applied because of its simplicity and low treatment cost,and it is beneficial to the subsequent utilization of sediment. In order to investigate a suitable biological treatment process and demonstrate the variations of microbial community during the biological treatment process,four types of biological agents( nitrifying bacteria,denitrifying bacteria,photosynthetic bacteria,and bacillus) were used for ectopic treatment of black and odorous water sediment. Different dosages of biological agents were added,and variations of total nitrogen( TN),total phosphorus,organic matter and water content in the sediment before and after the reaction were compared. After treatment of 30 days at room temperature( 20 ± 5) ℃,water content,total nitrogen,and organic matter in the sediment all decreased to different degrees. Among them,the denitrifying bacteria group with dosage of 35 mg/L had the best treatment efficiency: removal efficiencies of total nitrogen and organic matter reached 59. 90% and 20. 93%,respectively. Three-dimensional fluorescence spectrum analysis showed that the concentration of macromolecular organic matter in the sediment decreased and the concentration of small molecular matter increased in different degree after adding pure biological agent. This indicated that the biological agents improved the activity of microorganisms in the sediment,not only promoting the degradation of organic matter,but also providing carbon source for denitrification and promoting the removal of total nitrogen in the sediment. Furthermore,high-throughput sequencing also showed that Thiobacillus,Sulfurovum,Sulfuricurvum and Sulfurimonas were observed in all experimental groups with addition of biological agents,and the higher proportions in experimental groups with addition of bacillus and photosynthetic bacteria( total proportions of the four genera reaching13. 24% and 14. 80%,respectively) were detected. These four genera were related to sulfur metabolism and might play an important role in the degradation of organics,such as proteins,in the sediment.