Abstract

In this study, we isolated two bacterial strains, P2 (Pseudomonas geniculata ATCC 19374, P. geniculata ATCC 19374) and B1 (Bacillus cereus EC3, B. cereus EC3) from pig farm soil, which were mixed to construct a novel bacterial mixture (P2:B1 = 1:1). We studied the heterotrophic nitrification capablity and growth characteristics of bacterial mixture in heterotrophic nitrification medium (HNM). And the factors affecting the nitrogen removal of the bacterial mixture such as C/N ratio, NH₄⁺-N load and inoculation size of the bacterial mixture were investigated in this study. Furthermore, we used the bacterial mixture to treat livestock wastewater to remove NH₄⁺-N, TN and COD. The results showed that the optimal C/N ratio and inoculation size for the bacterial mixture were 12 and 5%, respectively. It is worth to mention that the bacterial mixture shows excellent NH₄⁺-N removal ability under low C/N ratio, indicating that the bacterial mixture had the potential to be applied to wastewater with C/N lower than 8. When the initial NH₄⁺-N concentration was 500 mg/L, the NH₄⁺-N removal efficiency exceeded 90% with a 5% inoculation size of the bacterial mixture after 72 h. When the single bacteria and bacterial mixture were employed to treat livestock wastewater, the removal efficiencies of bacterial mixture on NH₄⁺-N, TN and COD within 72 h were 70.06%, 58.12% and 81.48%, respectively, which were higher than that of single bacteria. The bacterial mixture has potential application value in enhancing the ability of reactors and constructed wetlands to remove pollutants from livestock wastewater and developing a novel and efficient biological nitrogen removal technology. Our current research provides a research basis for the application of the bacterial mixture in the future.

Graphic Abstract

中文翻译：

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假单胞菌ATCC 19374和蜡样芽孢杆菌EC3混合物在畜禽废水处理中的潜在应用

摘要

在这项研究中，我们分离的两种细菌菌株，P2（假单胞菌膝ATCC 19374，P.膝ATCC 19374）和B1（蜡状芽孢杆菌EC3，蜡状芽孢杆菌EC3）从养猪场土壤，将它们混合以构建新的细菌混合物（ P2：B1 = 1：1）。我们研究了异养硝化硝化能力（HNM）中细菌混合物的异养硝化能力和生长特性。并研究了影响细菌混合物脱氮的因素，如C / N比，NH ₄ ⁺ -N负荷和细菌混合物的接种量。此外，我们使用细菌混合物处理畜禽废水以去除NH ₄ ⁺-N，TN和COD。结果表明，细菌混合物的最佳C / N比和接种量分别为12和5％。值得一提的是，该细菌混合物在低C / N比下显示出优异的NH ₄ ⁺ -N去除能力，表明该细菌混合物具有适用于C / N低于8的废水的潜力。₄ ⁺ -N浓度为500 mg / L，72小时后，细菌混合物的接种量为5％时，NH ₄ ⁺ -N去除效率超过90％。当单一细菌和细菌混合物用于处理家畜废水时，细菌混合物对NH ₄ ⁺的去除效率72 h内的-N，TN和COD分别为70.06％，58.12％和81.48％，高于单一细菌。这种细菌混合物在增强反应堆和人工湿地从牲畜废水中去除污染物的能力以及开发一种新颖而有效的生物脱氮技术方面具有潜在的应用价值。我们目前的研究为将来细菌混合物的应用提供了研究基础。

图形摘要