| Summary: | 碩士 === 中興大學 === 環境工程學系所 === 99 === In respect of aquaculture, the excess of fodder and metabolism activity of aquatic organism or excrement may result in the deterioration of water quality as the accumulation of nitrous acid and ammonia nitrogen causes considerable propagation of bacillus. Chlorine dioxide possesses powerful oxidization and disinfection abilities, nevertheless, the research regarding utilization of chlorine dioxide applied in aquaculture in domestic area is not sufficient. The research utilize ready-made high purity chlorine dioxide to make three experiments as follows: treatment on purity material wastewater from artificiality, which is harmful to aquaculture: including freshwater and seawater solutions of nitrous acid, ammonia nitrogen and colon bacillus; treatment on cultivated aquatic organism in laboratory culture; measuring by means of Microtox on chlorine dioxide and inorganic by-products: chlorite and chlorate which may generate biological toxicity in water .According to the result of the research, it appears that high purity chlorine dioxide has significant effect of removal on nitrous acid either in freshwater or in seawater and with rapidity of reaction . Further, ammonia nitrogen does not take good effect in freshwater, while its removal rate in seawater has relation with concentrations of seawater and chlorine dioxide added；Moreover, the removal on colon bacillus in either freshwater or in seawater takes good effect, and it can reach 99.99%and 99.83% of disinfection rate if adding 0.25mg/L chlorine dioxide with reaction time for 15minutes .In terms of wastewater treatment in laboratory culture , nitrous acid , colon bacillus and COD in aquatic organism provide significant effects of removal. In addition, according to the result of experiment on biological toxicity, it shows that chlorine dioxide has the highest toxicity, and the next is chlorite, while chlorate is almost out of toxicity.
|
|---|
