| Oxytetracycline is a kind of tetracycline antibiotics.There is a large market demand for oxytetracycline in China.The production process will increase the discharge of wastewater.Because of the high pollution load of antibiotic wastewater and the rapid change of water quality,the residual substances in antibiotic wastewater do great harm to the environment,which makes it more difficult to treat.Therefore,researchers need to pay close attention to relevant fields and find out more economic,effective and environmental protection technology to solve this problem.In this paper,the wastewater from mother liquor of oxytetracycline is studied.Its main pollution factors are COD and sulfate.The main components of COD are carbohydrate,protein and oxalic acid,followed by oxytetracycline,which is an important evaluation index of water quality.Based on the analysis and summary of the current treatment methods and processes of oxytetracycline wastewater,the biological treatment method of microbial fermentation is proposed,and a reasonable comprehensive wastewater treatment process is designed.The characteristics of wastewater containing high sugar and high protein organic substances and biological active substances are used as the natural medium to consume and decompose the existing pollutants through the added microorganisms,with the maximum limit In order to improve the degradation rate of COD and the removal rate of oxytetracycline,the purpose of water purification can be achieved.However,up to now,only a few strains can be found and applied in the process of biological treatment of oxytetracycline wastewater.Therefore,it is a crucial prerequisite to find a more likely high-quality strain in the treatment process.In this project,10 strains selected from the early laboratory were added to the wastewater of oxytetracycline in different ways for fermentation,and COD value and oxytetracycline titer were measured respectively.According to the effect of oxytetracycline on wastewater fermentation,the superior strains with high performance on wastewater degradation were explored,and the conditions of wastewater degradation by the superior strains were optimized to determine the best process parameters,which is helpful to solve the hot spot It is of far-reaching significance to study problems,recycle resources and accelerate economic development.The results of this study are as follows:1.Explore the impact of wastewater treatment on the reduction of COD value.After two methods of wastewater treatment,including unsterilization and sterilization,10 kinds of bacterial suspension were added and fermented in an electric constant temperature shaker at30?and 180r/min for 4 days.A certain amount of wastewater fermentation liquid was taken every day.The COD value before and after the reaction was quickly determined by spectrophotometry,and the COD degradation rate was calculated.Through data analysis and comparison,the method of adding bacteria suspension after wastewater sterilization treatment to reduce COD value is better,which has certain regular trend and is convenient for further screening of bacteria.2.To study the effect of two different ways of adding bacteria on reducing COD value of wastewater.On the basis of wastewater sterilization,10 kinds of 10~8/m L bacterial suspension and bacterial culture solution were added to every 100m L of wastewater respectively,and fermented in an electric constant temperature shaking table at 30?and 180r/min for 4 days.Samples were taken at the same time every day,and the COD value was determined rapidly,and the COD degradation rate was calculated.Through data analysis,it is concluded that the treatment method of adding strain culture liquid is more effective for degradation of wastewater,and yeast and Bacillus amylolyticus can be selected as the dominant strains.After adding,the degradation rate of COD in wastewater is the highest on the third day of fermentation,reaching 82.6%and 77.7%respectively.3.To explore the effect of strains on the removal of oxytetracycline from wastewater.Take 100m L of terramycin mother liquor wastewater from each bottle,add 10m L of 10 kinds of bacterial suspension with 10~8/m L bacterial amount for fermentation for 4 days,measure the residue of terramycin every day,and calculate the removal rate of terramycin.Through data analysis,it is concluded that the removal efficiency of oxytetracycline from yeast wastewater is the best on the second day,and the removal rate is 75.6%.At the same time,the p H value of the fermentation liquor is higher than that of the original liquor,that is to say,the acidity of the wastewater is reduced,a large amount of acid and alkali for regulation is saved,and the cost is low,which is conducive to further treatment and discharge or resource utilization.Among them,the p H value of CMC decomposing bacteria wastewater fermentation liquid is relatively high at 5.63,indicating that CMC decomposing bacteria has a strong ability to consume oxalic acid.4.Observe the colonies of yeast and Bacillus amylolyticus on the corresponding medium,and observe their morphological characteristics under the microscope to understand their characteristics.Through single factor experiment,the conditions of COD value of wastewater degradation by dominant strains were optimized,and the effects of strain addition,rotation speed and temperature on wastewater treatment were explored.The results showed that when the yeast dosage was 15%,the degradation rate of COD in wastewater from oxytetracycline mother liquor was as high as 80.4%,while the degradation rate of COD in wastewater from Bacillus amylolyticus was as high as 81.3%.When the rotation speed of yeast wastewater fermentation liquid is 180r/min and that of starch Bacillus wastewater fermentation liquid is200r/min,the degradation rates of COD by the two strains are 83.2%and 78.5%respectively.The results showed that when the temperature was 27?,the highest degradation rate of yeast to fermentation wastewater was 80.3%;when the temperature was 30?,the degradation rate of COD by Bacillus amylolyticus to fermentation wastewater was 76.3%. |
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