| With the outbreak and prevalence of COVID-19 around the wo rld,the disinfection of public places and home environments has becom e thenew normal condition,so there is a huge demand for safe and effi cient disinfection products in the market.sodium hypochlorite solution ha s become an indispensable epidemic prevention material as a kind of di sinfection productwith broad spectrum sterilization effect.Based on the r esearch of preparing sodium hypochlorite disinfectant by electrolysis met hod,this paper plans to design a real-time disinfectant generator with to w concentration salt water as raw material,no dilution and high steriliz ation efficiency,which has important practical value and great social sig nificance.Firstly,the effects of five process parameters,including brine f low rate,salt concentration,current density,inlet temperature and pH va lue,on the preparation of sodium hypochlorite disinfecting water by ele ctrolysis were studied by single factor experiment.The five process para meters were optimized with the effective chlorine concentration,current efficiency and operating cost as evaluation indexes.The results showed t hat when the brine flow rate was 75 mL/min,the mass concentration of brine was 7 g/L,the current density was 1 A/dm2,the inlet temperature was 30℃,and the pH was 7,the effective chlorine concentration of th e electrolytic effluent was 455 mg/L,the current efficiency was higher and reache 23.8%,and the operating cost is the lowest,which was 24.8 yuan/kg.Then,the apparent kinetics of the reaction was investigated,and it was determined that the reaction was a first order reaction.The relati onship between the initial mass concentration of salt A and current dens ity J and the reaction rate constant k was concluded as:k=0.007a-0-459 a nd k=0.003j0.423,respectively.In order to improve the electrolytic efficie ncy,the structure ofthe electrolytic cell was optimized.The results show ed that the best electrolytic effect was achieved when the cylindrical ele ctrolytic cell,the length-diameter ratio of the electrode was 3.4,the imm ersion depth of the electrode was 12 cm,and the distance between the anode and the anodewas 1 cm.At this time,all the chlorine produced by the anode could be absorbed.Next,the main components of the disin fecting water generator were calculated and selected,mainly involving s alt water tank,electrolyzer,disinfecting water storage tank,salt pump,d isinfecting water spray pump and nozzles,etc.In addition,the control sy stem of the device was designed and debugged,and the linkage controls ystem with the liquid level as the input condition was finally realized.Finally,the sterilization effect of sodium hypochlorite disinfecta nt prepared by the disinfectant water generator was evaluated.The results showed that the effective chlorine concentration of 100 mg/L disinfectan t with Escherichia coli,Staphylococcus aureus after 15 min,the killing ratecan reach 99.9%;The effective chlorine concentration of 150 mg/L disinfectant treated with Bacillus subtilis,Candida albicans for 25 min,t he killing rate could reach 99%.The bacterial killing rate increased gra duallywith the increase of effective chlorine concentration and the decrea se ofpH value.When the concentration of 10-4 mol/L BUCT was mixed into the disinfectant,the surface wettability and bactericidal effect of the disinfectant were significantly improved.Finally,through comparative ex periments,it was found that the sterilization effect of the three kinds of disinfectants was ranked as follows:homemade disinfectants>with BU CT,homemade disinfectants>and 84 disinfectants sold in the market. |
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