絮凝剂BF-11的制备及其在淀粉废水处理中的应用

Preparation of Bioflocculant BF-11 and its application in starch waste water treatment

对絮凝剂BF-11的制备、性质及其在淀粉废水处理中的应用进行研究,为该絮凝剂的工业化生产及其在淀粉废水处理中的应用提供理论依据。絮凝剂的制备采用有机溶剂沉淀方法,多糖含量的测定采用苯酚—硫酸法,废水SS的测定采用重量法、COD的测定采用重铬酸钾法。用2倍体积95%乙醇—丙酮(1∶1)在0℃、pH值为8的条件下沉淀5 m in,1 L发酵液可得絮凝剂BF-11产品5.74 g,推测其主要成分为多糖。絮凝剂BF-11对淀粉废水絮凝的最佳条件为:每100 mL废水投加BF-11 0.01 g,1%CaC l25 mL,在pH 8的条件下沉降30 m in。在该条件下,COD cr去除率可达81.74%,SS去除率可达92.14%,絮凝效果优于聚合氯化铝(PAC)和聚丙烯酰氨(PAM)。该絮凝剂产率高,对淀粉废水净化效果好,用量小,无二次污染,并可回收利用淀粉废水中有用成分,具有很好的经济效益和社会效益。

The optimum preparation conditions of bioflocculant BF-11, its properties and its application in starch waste water treatment were studied, in order to provide theory basis for BF-11＇s industrialization and application in starch waste water treatment, bioflocculant BF-11 was prepared through organic solvent precipitation. The determination of the contents of polysaccharide was performed by phenol-sulfuric acid method. The SS of waste water was determined by weight method, and COD was determined by potassium dichromate method. Precipitated by 2 volume 95% ethanolacetone （ 1 ： 1 ） at 0 ℃ and pH 8 for 5 min,5.74 g bioflocculant BF-11 product can be obtained from 1L culture broth, it was inferred that its main components is polysaccharide. The optimum conditions for coagulation in starch waste water treatment were as follows： add BF-11 0.01 g and 5 mL 1% CaCl2 respectively per 100 mL waste water, maintain pH 8.0 and precipitate 30 min. Under this conditions, the CODcr removal ratio can reach 81. 74%, and the SS removal ratio is 92.14% ,which is better compared to polyaluminum chloride and polyacrylamide, This bioflocculant has high yield. It has good effects on starch waste water purification, without causing secondary pollution, and the useful ingredients can be recycled. The results indicated that BF-11 has good economic benefits and social benefits and has wide prospect of application.