多相纳秒脉冲介质放电与光催化协同过程处理压舱水机理研究

Ballast water is necessary for the ocean-going ship. Exotic microorganisms, animals and plants carried by ballast water cause heavy damage to the local marine ecology system. It has been thought as one of the four threats of the global ocean. Up to now, all sorts of ballast water treatment technologies can't be applicated and spreading in large scale for their own defects. In liquid phase pulsed discharge, there generates ultraviolet, strong electric field, shock wave and active species. Ballast water is treated effectively by multiple effects in pulsed discharge. However, the metal discharge electrode is eroded easily in the ballast water and the power efficiency of the pulsed discharge is low. In order to solve these problems, in this project, a dielectric layer is added to the discharge electrode, and the TiO2 is coated on the dielectric layer. Dielectric can block the corrosion of the ballast water to the metal electrode and the TiO2 can be catalyzed by the ultraviolet in the pulsed discharge, the amout of the active species increased. The specific research are as follows: the desigh of the discharge electrode and the measurement of the discharge characteristics; the diagnosis of the hydroxyl radicals' concentration and spacial distribution by optical emmision spectroscopy; the chemical analysis of the concentration of the ozone and the Hydrogen Peroxide; the treatment experiments of the ballast water. The treatment mechanism of the ballast water by the gas-liquid-solid phases pulsed barrier discharge with photocatalyst is given through the ways of the experiments, the theory analysis and the numerical simulation.

压舱水是远洋船舶安全航行所必须的。压舱水携带进入本土海洋环境的微生物和动植物严重破坏当地生态系统，已被确定为全球海洋面临的四大威胁之一。众多压舱水处理手段由于各种缺陷难以大规模推广应用。液相脉冲放电产生紫外光、强电场、冲击波和活性物质，多种效应叠加作用可实现对压舱水的有效处理，但水中放电极易被腐蚀、能量效率低。针对这一问题，本项目对放电极添加镀二氧化钛光催化剂的绝缘层，以减少对放电极的腐蚀；二氧化钛可被脉冲放电过程的紫外光催化，生成羟基等活性自由基，与多相纳秒脉冲放电过程协同作用可提高对压舱水的处理效率。具体研究：多相纳秒脉冲介质放电和光催化协同过程放电极设计及放电特性的电气测量；羟基自由基浓度和空间分布的发射光谱诊断；臭氧和过氧化氢的浓度的化学法测定；压舱水处理及微生物灭活效果实验。通过实验、理论分析和数值模拟相结合，给出多相脉冲介质放电与光催化协同过程的压舱水中微生物的灭活机理。

压舱水是远洋船舶安全航行所必须的。压舱水携带进入本土海洋环境的微生物和动植物严重破坏当地生态系统，已被确定为全球海洋面临的四大威胁之一。液相脉冲放电产生紫外光、强电场、冲击波和活性物质，多种效应叠加作用可实现对压舱水的有效处理。本项目对放电极添加镀二氧化钛光催化剂，二氧化钛可被脉冲放电过程的紫外光催化，增加放电过程羟基自由基的数量，与多相纳秒脉冲放电过程协同作用可提高对压舱水的处理效率。主要研究内容包括多相纳秒脉冲放电和光催化协同过程放电极设计及放电特性的电气测量；羟基自由基浓度的发射光谱诊断,放电等离子体特性模拟分析；臭氧和过氧化氢的浓度的化学法测定；压舱水处理及微生物灭活效果试验。研究结果表明多相纳秒脉冲放电协同二氧化钛光催化过程可有效实现对压舱水中藻类、菌类的灭活，降低浊度。给出了系统电气特性、不同放电形式、电气参数等对放电等离子体生成的影响规律及对以藻类等为迷惑目标物的压舱水处理效率的影响规律。该项目的研究为放电等离子体技术处理压舱水的机理及提高处理效率的研究提供了依据。