O_(3)/H_(2)O_(2)高级氧化技术对船舶压载水中微藻处理的研究

Study on the O_(3)/H_(2)O_(2) Advanced Oxidation Treatment of Microalgae in Ship’s Ballast Water

为了研究满足国际海事组织(IMO)制定的压载水排放标准的处理技术,建立了臭氧联合过氧化氢(O_(3)/H_(2)O_(2))的新型高级氧化技术体系(AOP),以单类藻种(青岛大扁藻、新月菱形藻)和混合藻种(青岛大扁藻:新月菱形藻=1∶1)为目标微藻,通过改变藻的种类、初始藻密度,氧化剂的浓度以及反应时间来探究此技术处理船舶压载水中微藻的杀灭效果。结果表明:在高剂量的TRO(>2 mg/L)浓度下,反应时间在20 s的时候就能达到D-2的要求,在面对复杂的混合藻种时,臭氧的生物杀灭功效比起处理单种藻类时更高也更快见效,当达到一定的臭氧浓度后,再继续通入臭氧也只会保持原有的生物杀灭速度。杀灭时间较短时(<10s),不同藻种中杀灭难度最大的是青岛大扁藻,最易杀灭的是混合藻;杀灭时间为20 s~40 s时,最易杀灭的藻是混合藻,单一藻种的杀灭效果相差不大;反应时间在40 s~60 s时,各种藻种的杀灭速度均小于前40 s的杀灭速度;杀灭时间大于60 s时,最难杀灭的是新月菱形藻,最易杀灭的是混合藻。该实验结果对探究高效的船舶压载水处理技术提供了理论依据,并为实际工程中船舶压载水的处理奠定基础。

A ballast water treatment system based on O_(3)/H_(2)O_(2) advanced oxidation process(AOP)was investigated to explore if its killing efficacy could meet the discharge standard according to the International Maritime Origination(IMO).Single algae species(i.e.,Platymonas helgolandica and Nitzschia Closterium f minutissima)and mixed algae species(i.e.,Platymonas helgolandica:Nitzschia Closterium f minutissima=1:1)were used as target microalgae.By changing the types of algae,initial algae densities,concentrations of oxidant and reaction time,the killing effect of microalgae in ship ballast water treated by this technology was investigated.The results showed that at high dose TRO(>2 mg/L),the reaction time reached the requirement of D-2 at 20 s.In the face of the complex mixed effects,ozone showed a higher and faster killing performance to single algae than mixed algae.However,ozone had a limited killing performance with a certain dose.Within reaction time less than 10 s,Platymonas helgolandica was the hardest algae to be killed among the different algae species and mixed algae was the easiest algae to be killed.Within reaction time between 20 s to 40 s,the easiest algae to be killed is mixed algae and the killing effect of a single algae species is not much different.The killing speed with a reaction time between 40s and 60 s is slower than the first 40 s.The most difficult algae to be killed is Nitzschia Closterium f minutissima with reaction time more than 60 s.These experimental results provide a theoretical basis for the exploration of efficient ship’s ballast water treatment technologies,and lay a foundation for ship’s ballast water treatment in practical engineering.