利用酵母菌处理高浓度味精废水的研究

【作者】 黑亮；

【导师】 张嵩午；

【作者基本信息】 西北农林科技大学 ， 生态学， 2002， 硕士

【摘要】 随着工农业生产的发展，我国生态环境逐渐恶化，尤其水域环境污染严重，有机废水特别是高浓度有机废水的污染问题迫在眉睫，它一直是废水处理行业的热点和难点。 味精废水主要含有菌体蛋白、残糖、氨基酸、铵盐、有机酸及硫酸根等污染物，废水COD负荷高达20000～70000mg／L，pH3.2，属于亟待解决的高浓度酸性有机废水。由于其BODs／COD比值为0.86，可生化性高，适合采用生物处理法。 酵母菌是一种真菌。据其分布情况表明，经过长期的自然选择，酵母菌对高糖环境、高碳环境、高渗透压环境等具有较强的适应性，这使其有可能应用于高浓度有机废水的处理；并由于其利用的碳源种类非常广泛，使其可应用于不同有机废物的治理。酵母菌对有机废水的处理主要表现为不仅可以在一定程度上降低有机物的污染，还可同时利用有机废水生产单细胞蛋白(SCP)，从而实现废水的资源化。 本研究主要是利用酵母菌对味精废水进行了连续小试处理。通过批量实验对从高浓度味精废水中筛选出的一组酵母菌混合菌群进行了脱氢酶活性(DHA)测试，结果表明用该菌群对COD、硫酸根和氨氮均接近20000mg／L的味精离交尾液进行处理时，其DHA值在前36h高于对离交尾液稀释液的处理，说明高浓度氨氮和硫酸盐对酵母菌活性的影响不显著。利用接种了该酵母菌群的生物接触氧化反应器对味精废水进行的连续小试处理结果表明，在恒温28℃，DO为4mga,条件下，COD容积负荷为2.0～14.3kg／(m~3·d)范围内，COD去除率稳定在80％以上；适当地补充磷源有利于维持稳定的处理效果。对出水pH值和COD去除率的关系进行了探索，发现pH值对COD的去除影响并不大，而酵母菌生长的最佳pH值为3.5～5.0。处理后的出水SS升高，其中含有大量的酵母菌体，成分分析结果表明菌体蛋白含量为57.9％，氨基酸分布均衡，可以回收为饲料添加剂。将酵母菌反应器后出水再经活性污泥反应器进行二级后续处理，废水在生物处理后的出水COD去除率达到93％以上。 同时，对味精废水氨氮的去除、酸化(水解)对废水的处理、混凝批量试验的净化研究进行了一系列的探索性试验，结果表明，酸化工艺的效果不大；若以聚铁为混凝剂，可以使出水的COD最终降至360mg／L左右。更多还原

【Abstract】 With the development of industry and agriculture, our environment deteriorates gradually, especially water area pollution. The treatment of high concentration organic wastewater is always a hotspot and a difficulty in wastewater treatment.Monosodium glutamate wastewater contain much contamination, such as thalli albumen, remnant sugar, amino acid, ammonium salt, organic acid, SO42". The COD of the water is 20000~70000mg/L, pH3.2, belonging to the high concentration organic wastewater to solve urgently.Yeast is a kind of fungi. Distributing of yeasts indicates that after the natural selection for a long time, yeasts fit on the surroundings of containing high concentration sugar, high concentration carbon, or high infiltration pressure, which makes it possible to apply to the treatment of the high concentration organic wastewater. The carbon fountain categories of yeasts using are very wide, which makes it possible to apply to the treatment of the different organic waste. The manifest of the treatment of the organic wastewater using yeast is not only reducing the pollution degree of the organic waste, but also gaining the SCP as well by using the waste as a resource.The laboratory-scale continuous treatment of monosodium Glutamate manufacturing wastewater used yeast in the study. DHA (dehydrogenation activity) test indicated that mixed yeast strains isolated from high strength monosodium glutamate wastewater could endure the high concentrations of COD, S042", and NH}"1" containing in glutamate wastewater. The mixed yeast strains were inoculated to a biological contact oxidation reactor, and the reactor was used to treat the glutamate wastewater. Under a COD load ranging from 2.0 to 14.3kg/(m3 ?d), the COD removal rate was over 80%. On the other hand, supplementation of phosphorus was necessary to maintain a stable COD removal performance. Variation of effluent pH seemed to have no apparent influence on COD removal rate. The optimum pH for the growth of yeast, however, was found to be in the range of 3.5~5.0. The effluent wastewater contained high concentration of yeast bodies, which could be utilized as a forage additive because of its high protein content (57.9%) and well-balanced amino acid distribution. The effluent wastewater using yeast was treated by activated sludge, and the COD removal rate was 93% finally.Moreover, a series of exploring experiments of the NH4+-N removal, hydrolyzation of wastewater, coagulation purify study showed that the effect of the acidification is small, and the COD was about 360mg/L by polymerizing FeCla.更多还原