The Research On Substitutional Substrate Of Bioflocculant-producing Strain And Decontaminating Characteristic And Its Componential Analyse Of Bioflocculant

Bioflocculants, having good flocculating activity, are the metabolic products of the microorganism, which are safe, non-toxic , easily cultivated, and can be biodegraded. Its main components are amylose, glycoprotein, nucleic acid, protein etc. Since the advantages of using bioflocculants in both environmental safety and economic over some other inorganic flocculants and organic flocculants, great attention has been payed to explore the bioflocculants mechanism and to investigate their characteristics in use. As a result, it is of great value in the research of bioflocculant.In this study, 3 strains of bioflocculant-producing microorganisms are screened from activated sludge taking from wastewater treatment plant and soil in Changsha, respectively One is named B23 identified to be Aspergillus fumigatus Fres.The two others are belong to bacterium, named N10 and N11, and bioflocculant produced by them are respectively named as MBF10 and MBF11. The substitutional substrate for B23 cultivation was investigated, at the same time, the capability of heavy metal removal by N10 is also studied. Finally, the components of MBF10 were analyzed and determined after purified and extracted by ethanol.Experimental results showed that MBF23 can grow on many kinds of substrates, and its flocculation capability are generally better than that of FeSO4, FeCl3 ,AlCl3, but related to PAC, CTS and amic-polypropylene. The results also showed that a mixture of soybean liquor and raisin liquor (5g/L) with the ratio 1:1 can be used as a substitutional substrate for MBFB-23 production. A high flocculating activity could be obtained when C/N was limited in the range of 15 to 25. The cultivation cost with this kind of substrate is therefore reduced to only about 8%-9% of the one with GC.The studies on the bioflocculant produce process by B23 showed that the substitutional substrate is easy to get.The MBF10 showed a good perfermance when used for the treatment of some kinds of wastewater, such as beer wastewater, hoggery wastewater, demestic wastewater, blue ink wastewater and etc. After orthogonal experiment it was found that the main factors affect MBF10 in wastewater treatment are pH, SS and the quantity of bioflocculant. At the same time,the optimal conditions for MBF10 in wastewater treatment are obtained as follows(pH=8.5, concentration of MBF10=15-25 %.), through orthogonal test.The experiments also indicated that MBF10 also showed...