Simulated Experiment on Removing Nitzschia Closterium in Ballast Water by Combination of Micro-pore Filtration and UV Radiation

摘要

For minimizing the harmfulness of invasive exotic species in ballast water to the marine environment, the study worked on a ballast water treatment system using micro-pore filtration and UV radiation. In the simulated experiment, nitzschia closterium was selected as indicator organism in seawater, and its removal rates were investigated at the flow rates of 1-9m3/h and at the initial alga concentration of 1×04-2×05 cells·L-1. In addition, transmission electron microscope was used to observe the changes of alga cells after filtration and UV radiation treatments. The results showed that the removal rate on nitzschia closterium by the combination treatment was 94% in average, and it was observed that cell walls of nitzschia closterium were damaged during the micro-pore filtration, and cell walls and nucleus were ruined during the UV radiation. It is proved that the combination of micro-pore filtration and UV radiation is feasible in removing algae of ballast water.