Evaluation Of Ship Ballast Water Rapid Inspection Equipment And Photocatalytic H₂O₂ Inactivation Technology

With the entry into force of the ballast water convention in China,the research on rapid detection and efficient inactivation of microorganisms in ballast water is of great significance.At present,it is difficult to ensure the accuracy of the rapid detection equipment for the indicative analysis of ballast water,and the ballast water treatment technology also has some problems,such as low treatment efficiency,difficult to ensure stability and long-term mechanism.Based on this,this paper carried out the comparative analysis and research of ballast water rapid detection equipment,and used ultraviolet catalysis combined with hydrogen peroxide technology to inactivate bacteria and microalgae in ballast water,which provided a theoretical basis for seeking an efficient ballast water inactivation treatment process.Aiming at the low accuracy of ballast hydration gauge detection equipment（CMDS）,the performance of mainstream ballast water rapid detection equipment was tested to explore the impact of different water quality environmental factors（turbidity and soluble natural organic humic acid concentration）and biological factors（dead algae and algae cell concentration）on the rapid detection equipment,It is found that the ballast water quality parameters will affect the indicative analysis results of CMDS.The results of weight factor analysis show that the concentration of dead algae and algal cells has the greatest impact on the detection accuracy of CMDS.We need to focus on these two factors in the investigation of rapid detection equipment.The study on the inactivation of bacteria and microalgae shows that UV catalysis combined with hydrogen peroxide technology is feasible for the inactivation of microalgae and bacteria in ballast water.When the UV radiation intensity was 44.2 m W/cm²,the average load of Ti O₂ was 9.48 mg/cm²,and the influent H₂O₂ concentration was 20 mg/L,the logarithmic inactivation rates of Escherichia coli,Enterococcus and Prorocentrum microalgae could reach 5.86 log,5.23 log and 3.11 log respectively within 5 minutes.Mechanism research shows that the system can effectively inactivate bacteria and microalgae cells,cause irreversible damage to cell structure and cause their death.The content of lipid peroxide（MDA）of bacterial cells increases to 101 nmol/L,the activity of superoxide dismutase（SOD）rapidly decreases to 51.7 U/mg pro,and the chlorophyll a of microalgae is rapidly degraded to 5.3μg/L.The UV/Ti O₂/H₂O₂ disinfection reactor model based on CFD was established,and the structural optimization design and numerical simulation were carried out.The flow pattern of the guide vane sterilizer with different parameters is simulated and calculated.The results show that setting the guide vane at the inlet and outlet of the sterilizer can change the concentration of water flow and homogenize the velocity distribution.The existence of the guide vane is conducive to the generation of secondary circulation in the reactor and can develop into eddy current,so as to ensure the full mixing of water flow and microorganism in the reactor with H₂O₂,so as to improve the disinfection performance,and optimize the best guide vane parameters.The light intensity simulation results show that there is no dead angle in the reactor,which can effectively irradiate the water in the reactor.