State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China..
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China.
J Environ Sci (China). 2014 Oct 1;26(10):2076-83. doi: 10.1016/j.jes.2014.08.007. Epub 2014 Aug 13.
The optimized production of a novel bioflocculant M-C11 produced by Klebsiella sp. and its application in sludge dewatering were investigated. The optimal medium carbon source, nitrogen source, metal ion, initial pH and culture temperature for the bioflocculant production were glucose, NaNO3, MgSO4, and pH7.0 and 25°C, respectively. A compositional analysis indicated that the purified M-C11 consisted of 91.2% sugar, 4.6% protein and 3.9% nucleic acids (m/m). A Fourier transform infrared spectrum confirmed the presence of carboxyl, hydroxyl, methoxyl and amino groups. The microbial flocculant exhibited excellent pH and thermal stability in a kaolin suspension over a pH range of 4.0 to 8.0 and a temperature range of 20 to 60°C. The optimum bioflocculating activity was observed as 92.37% for 2.56mL M-C11 and 0.37g/L CaCl2 dosages using response surface methodology. The sludge resistance in filtration (SRF) decreased from 11.6×10(12) to 4.7×10(12)m/kg, which indicated that the sludge dewaterability was remarkably enhanced by the bioflocculant conditioning. The sludge dewatering performance conditioned by M-C11 was more efficient than that of inorganic flocculating reagents, such as aluminum sulfate and polymeric aluminum chloride. The bioflocculant has advantages over traditional sludge conditioners due to its lower cost, benign biodegradability and negligible secondary pollution. In addition, the bioflocculant was favorably adapted to the specific sludge pH and salinity.
研究了 Klebsiella sp. 产生的新型生物絮凝剂 M-C11 的优化生产及其在污泥脱水中的应用。生物絮凝剂生产的最佳培养基碳源、氮源、金属离子、初始 pH 值和培养温度分别为葡萄糖、NaNO3、MgSO4、pH7.0 和 25°C。成分分析表明，纯化的 M-C11 由 91.2%的糖、4.6%的蛋白质和 3.9%的核酸（m/m）组成。傅里叶变换红外光谱证实了羧基、羟基、甲氧基和氨基的存在。在高岭土悬浮液中，微生物絮凝剂在 pH4.0 至 8.0 范围内和 20 至 60°C 范围内具有出色的 pH 和热稳定性。使用响应面法观察到最佳生物絮凝活性为 2.56mL M-C11 和 0.37g/L CaCl2 剂量时为 92.37%。污泥过滤阻力（SRF）从 11.6×10(12)降低到 4.7×10(12)m/kg，表明生物絮凝剂调理显著增强了污泥脱水能力。M-C11 调理的污泥脱水性能比无机絮凝剂（如硫酸铝和聚合氯化铝）更有效。生物絮凝剂具有成本低、生物可降解性好、二次污染小等优点，优于传统的污泥调理剂。此外，生物絮凝剂还能很好地适应特定的污泥 pH 值和盐度。
