Research On Fed-batch Fermentative Process For The Bioflocculant Preparation

Biological safety as a purifying agent nontoxic, flocculation high activity, no secondary pollution of the new flocculent, is practical and significant to human and environmental protection, and then represents the flocculent one of the important research and development direction. However, most of the studies are at the laboratory stage. Because of the high cost of media, it limited the bioflocculant production and application to a large extent. Now the laboratory has developed a variety of bioflocculant more for Wastewater, Purification of high concentration and the elimination of livestock wastewater treatment sludge bulking. The Bioflocculant increase of urban sewage treatment research will have a broad prospect. In addition, water pollution, water scarcity problem has been quite prominent problem to the world, and the requirements of the governments'environmental quality show more stringent. Therefore, this study it should widen its scope of application, it should transformed to the practical application and industrialization as soon as possible, narrowing the gap with foreign countries. To this end, bioflocculant must enhance the production of bioflocculant yield, low the cost of production and research facilities dedicated to the research, to scale production to provide technical support, in order to enter the market. Therefore, the issue bases on lowering production costs, about the use of chitosan as a production of raw materials, and designing batch fermentation processes compound Bioflocculant development and research.The test FBC use " fed-batch culture " method, when ferment after some time, it will produce metabolites (the end period of growth of log ). Release part of the regular broth, and then add some fresh nutrient solution at the same time, and repeat. As the added fresh medium is the same as the original medium, canmaintain a certain level of bacterial growth rate, extend fermentation cycle, and improve product yield and reduce cost. Also for continuous fermentation experiments, which can be presented as controls.Flocculants bacteria in fermentation results of the study based on the experimental research on the bacteria batch fermentation experiments. On the conditions of increasing the volume of media analysis flocculation, the best inoculation will also change, measured by the tests: When activated strain, after training absorbance value reached 0.6 OD660nm seed broth, 3% inoculums is the best.After the experimental study of flocculently fermentation process of a series of changing parameters, it includes: the growth curve, pH, DO, the residual sugar concentration, the rate of flocculation broth and flocculants purified from yields and so on. In the experiments on the basis of summing up a batch fermentation parameters of the various trends : The growth curve in 48 hours when it reached the highest in the log ;60h after nearly steady growth curve, enters the period of endogenous respiration. PH first decreased and then increased, the dissolved oxygen in 12 hours after 0mg/L, residual sugar concentration decreased rapidly within 36 hours, and then remained stable. Flocculation broth rate and yield strains were cultured in 60 hours after it reached the highest and 92.77% respectively 3.67g/L. And the Task Force of the continuous fermentation compared to the experimental results, coagulant the increased output, flocculation rate stability, and the highest rate of flocculation shorten training time.The oxygen and timing of the fill material under the conditions of the flocculent-producing bacteria fermentation results show that when the dissolved oxygen concentration at 5-10mg/L, the parameters will have some changes to some extent: The growth curve in the rapid growth within 24 hours, maintain thepH range of 6-7, flocculation rate reach the highest yield. and 97.52% respectively 3.73g/L, fermentation conditions are higher than other similar circumstances which not regularly feed the fermenter. The conditions also flocculants from the best expanding culture fermentation conditions. The research results have some practical significance for future production provides a reference .Flocculant output hampered its production and the application of one of the major factors, while water is the environmental field researchers to solve pressing problems. In this study the optimum conditions for the extraction and purification of flocculants in the literature and experimental data on the basis of developed purification methods. Impact of various factors on the best extraction conditions: flocculation bacteria cultured for 60h, adjust pH 7 supernatant using ethanol purification reagent, ethanol dosage is greater than 1.6 times the volume of fermentation broth, and application of this method of purification - extraction yield reached 3.52g/L above. The results of this study for the application of bioflocculant provide a preliminary basis, also for the future bioflocculant production practice to provide references.It systematically sums up the compound microbial water purifying agent batch fermentation and purification processes, and provide theoretical basis for purifying agent for the industrialization of the production and promotion of the use , we anticipate industrial production of their products can come true at an earlier date.