Process Of High Yield And High Active Bioflocculant Produced By Klebsiella Sp.NIII₂ And The Study On Cationic Modifying Products

Microbial Flocculation is a new kind of preparations for watertreatment.It is widely concerned because of the advantages of its high flocculating activity,and non-pollution.The problems which hinder its industrialization are the high cost and the low stability.This paper means to optimize the yield and flocculating activity and we do some researches to give help for its industrialization.We study the process which can improve the yield,the relationship between content of SA in the MBF produced by Klebsiella sp.NIII₂ and yield and we improve the cationic modification method by the fermentation shaker,ultraviolet spectrophotometer,FT-IR,ELIASA,etc.The results of the studies got as follows:?1?There are some organic acid during the process of producing MBF by NIII₂.We find that when we add intermediate product of glycometabolism in the fermentation broth,and the yield gets better,especially pyruvic acid,?-ketoglutaric acid,succinic acid.Not only can they improve the yield and flocculation rate,but also improve the carbon conversion rate.?2?We use both acid micromolecule produced by the fermentation and saccharose during the process.We know that co-carbon can improve yield of MBF.It is great for saccharose and?-ketoglutarate sodium to be together and the yield is 11 g/L,carbon conversion rate is 42.3%.The proper tri-carbon makes process more stable,the yield higher and the flocculation rate better.The average yield of saccharose-sodium pyruvate-?-ketoglutarate sodium tri-carbon is abvove 11 g/L and the highest yield is 13.85 g/L,the flocculation rate is 97.5%.?3?The reason why co-carbon and tri-carbon can improve the yield and the flocculation rate is that the acid micromolecule can increase the secretion of SA and the content of protein in MBF.When the content of SA in MBF comes to 12 ng/g MBF,the yield can be always maintained 12 g/L.?3?Glycoprotein MBF produced by Klebsiella sp.NIII₂ is Nglycoprotein.Monosaccharides are rhamnose,mannose,galactose and glucose.Maybe it is complex glycoprotein or high mannose type N-linked glycan.The amino acids include tyrosine-like and tryptophan-like?4?We optimize the conditions of cationization with response surface method?RSM?:,and the best Zeta potential is 43 mV.When we deal with kaolin SS and alga,the capacity of cationization MBF is better than non-cationization MBF.Besides,the dosage is reduced.