Strengthen The Study Of The Effect Of Hydrodynamic Cavitation On The Removal Of Microorganisms In Water

Recently,the epidemic of infectious diseases caused by microbial contamination in water has received widespread worldwide attention.The outbreak and spread of these diseases pose a serious threat to the safety of human life and pose a public health and safety risk.So far,no one kind of disinfectant or technology has been developed to fully meet the disinfection needs.Only the appropriate disinfection technology can be selected according to the disinfection object and disinfection purpose.As a new type of environmentally friendly water treatment technology,Hydrodynamic cavitation has the advantages of simple installation,large capacity,environmental protection and no secondary pollution,but has the disadvantage of low removal rate.Therefore,more researchers propose the joint disinfection technology.Escherichia coli as a pathogenic microorganisms in water indicator bacteria to orifice plate as a cavitation reactor,based on the hydrodynamic cavitation,sodium hypochlorite disinfection and hydrodynamic cavitation combined with sodium hypochlorite enhanced oxidation disinfection of water E.coli removal effect.Low concentration of sodium hypochlorite has significant enhancement effect on hydrodynamic cavitation.The effect of hydrodynamic cavitation disinfection with 0.10 mg/L sodium hypochlorite is 1.27 times that of cavitation disinfection under the same experimental conditions and 2.47 times of that of sodium hypochlorite;0.20 mg/L sodium hypochlorite fortified The effect of cavitation disinfection is 1.43 times of that of cavitation under the same experimental conditions and 2.3 times of disinfection of sodium hypochlorite.When cavitation combined with sodium hypochlorite to remove E.coli,the two are mutually reinforcing and synergistic.The first-order linear model,Weibull model and Horn model were used to study the kinetic model of hydrodynamic cavitation combined sodium hypochlorite disinfection.The kinetic models of 1.0 mg/L,2.0 mg/L,3.0 mg/L,5 mg/L sodium hypochlorite four concentrations of the survival curve of E.coli were fitted,the results show that the Weibull model compared with the other two models is more suitable for hydrodynamic study on disinfection kinetics of cavitation combined Sodium Hypochlorite.Response surface analysis was used to investigate the effects of inlet pressure,sodium hypochlorite concentration and cavitation time on the removal of E.coli in water.The experimental data were analyzed and the parameters were optimized.The optimal parameters of hydrodynamic cavitation combined sodium hypochlorite enhanced oxidative disinfection process were:inlet pressure 0.37 MPa,sodium hypochlorite concentration 6.0 mg/L,cavitation time 38 min,initial concentration of E.coli 5.0×106 CFU/mL and water temperature 30?,Under this condition,the logarithm of E.coli removal is 4.96,which is close to the predicted value of the model,indicating that the process parameters obtained by the response surface optimization are reliable.In summary,hydrodynamic cavitation combined sodium hypochlorite enhanced oxidation technology can be used as a new type of water disinfection technology,in the removal of microorganisms in water has broad application prospects.