Study On The Immobilized Product By Solid-State Fermentation Of Efficient Advantages Bacteria To Treat The Industrial Wastewater

In recent years, with the rapid development of science and technology and industrial production, the type and quantity of organic matter in industrial wastewater which is mostly characterized by complex pollutant content, high concentration, toxicity, deep color and being difficult to be degradation are increasing fast. Traditional physical and chemical methods for degradating refractory high-strength industrial wastewater are not only high cost, but not ideal in the treatment effect, and most possible creating potential secondary pollution, thus, the conventional biological treatment technology is faced challenge.The subject aims to solve the problem of easy to drain and inconvenience on transportting liquid broth in industrial applications on the efficient dominant strain, the specified wastewater (coking wastewater, pesticide wastewater) are domesticate activated sludge gradiently and the tolerated advantage flora are obtained; strains are optimized, medium is expanded and the effect of temperature, pH, inoculum’s size and the growth of the dominant flora in culture are studied; homemade medium are added to the acclimated sludge to expand culture and obtain dominant bacteria culture medium. Solid-state fermentation are further used to inoculat dominant bacteria culture into new biomass of carrier rice husk and wheat bran, the fermentation conditions are controlled for solid-state fermentation by our homemade solid-state fermentation system, which is to obtain dominant bacteria of specified wastewater and achieve bacteria cultivation and preservation integration. In this work, surface methodology is used to optimize the solid-state fermentation conditions and the optimum fermentation conditions of nitrifying bacteria and pesticides bacteria are getted. By Comparing three solid-state biomass measurement methods and three preservation methods on the fermentation product, biomass measurement methods and preservation methods for solid-state fermentation product are given. Experimental process and results are as follows:(1) the Domestication of pesticide wastewater activated sludge: the pesticide wastewater is settled tank sludge acclimation, acclimated sludge tablet coating and microscopy experiments, the results show that the acclimated sludge are activestrains exist, pesticide wastewater advantage bacteria is optimized and the medium is expanded, it is shown that:the optimum growth medium for glucose (2g/100mL), Peptone (0.12g/100mL), ferrous sulfate (0.2g), potassium dihydrogen phosphate (0.5g), sodium chloride (0.01g), magnesium sulfate (0.02g), water (100mL); acclimated sludge is expanded culture of vaccination by20%of the inoculum size to the specified wastewater pesticide, COD removal rate was60.4%after two days.(2) Optimization of the dominant flora liquid submerged culture conditions:single factor test is used for the domestication of coking wastewater dominant bacteria (nitrifying bacteria, denitrifying bacteria) and bacteria of pesticide wastewater, nitrifying bacteria:the optimum pH (7-8), temperature (30℃), inoculum size (10%), incubation time on the dominant bacteriagrowth of group (1day);denitrifying bacteria:the optimum pH (7-8), temperature (25℃), inoculum size (15%), incubation time on the dominant bacteriagrowth of group (2day);the bacteria of pesticide wastewater:the optimum pH (7), temperature (30℃), inoculum size (15%), incubation time on the dominant bacteriagrowth of group (2day).(3) Changing the traditional method of immobilization, taking low cost biomass rice husk as a carrier, we use solid-state fermentation to prepare product. Using the experimental homemade drum fermentation system, a fixed product of the system was efficient and dominant flora. lOmL efficient advantage flora bacteria and5g wet efficient advantages of group immobilized products (10%vaccinated) were added into the nitrifying bacteria bacteria in100mL purpose of wastewater in the coking wastewater under the same experimental conditions, after2days, COD removal efficiencies of85%, in which the COD removal efficiency of immobilization was92%; Denitrifying bacteria bacteria removal rate of coking wastewater of78%, fixed-products of coking wastewater removal efficiency of88%; pesticide degrading bacteria pesticide COD removal rate of50%phosphorus removal efficiency of31%, the pesticide degrading bacteria immobilized product of pesticide COD removal rate was52.5%, the phosphorus removal efficiency of38.3%. The experiments show that:for the product of the immobilized the bacteria inoculation is less than solution of liquid flora conditions, removal efficiency is higher than the liquid broth, biological activity and removal rate is higher than liquid broth.(4) The immobilized product is different from the liquid broth and can not be directly measured biomass. Lipid phosphorus method, compared with ergosterol and TTC dehydrogenase activity method were used to study the characterization of immobilized biological activity. The results show that:because of containing lipid phosphorus in the biomass carrier rice husk, it is easy on the experimental results lead to considerable error; TTC dehydrogenase activity method which is not affected by the carrier and culture of the time, can better characterize immobilized biological activity. For biomass carrier rice husk, TTC dehydrogenase activity, immobilized products TTC dehydrogenase activity, optimization of nitrifying bacteria immobilized TTC dehydrogenase activity, denitrifying bacteria immobilized product TTC dehydrogenase activity, and pesticide degradation bacteria immobilized TTC dehydrogenase activity are determined to be0.49ugTF g-1.h-1,11.54h-1,16.8726ugTF g-1h-1,30.852ugTF g-1, h-1,17.0668ugTF/g/h, respectively.(5) Study on the solid-state fermentation product preservation method.The improved freezing preservation method, drying and the blast air-dried in industrial applications are used as immobilized products. A fixed number of products are divided into3parts, using the above three ways to save the immobilized enzyme activity measured after30days, the results show that:using freezing, drying and blast air-dried methods to save30d nitrification immobilized48h coking wastewater, COD removal efficiency were78.4%,70.37%,67.9%, respectively, which is higher than the51.23%used by the liquid culture of the bacterium. The effect of cryopreservation among the three preservation methods, freezing is best and blast drying is better than drying.