海水管道的外加阴极电流防生物污损机理研究

Study on mechanism of bio-antifouling by impressed cathode current in seawater pipe

根据流体动力学以及电化学相关理论,研究了外加阴极电流作用下海水管道内O2和OH-的浓度分布。结果显示:施加阴极电流后,靠近金属壁面的扩散层内构建了低溶氧、高pH值的环境,其远不同于大多数海生物生活的正常溶氧和近似中性的环境。同时发现,阴极电流和管径大小对O2和OH-浓度分布产生重要影响,阴极电流密度和管径越大,O2和OH-浓度差越大。从而论证了阴极电流可以抑制生物污损,电流越大,污损生物越难以附着。

In this paper, the effects of impressed cathode current on the concentration distribution of O2and OH- in the seawater pipe were investigated by hydrodynamics and electrochemistry theories. The results showed that a low DO and high 0H- concentration envi- ronment was produced near the inner surface in the pipe under the effect of cathodic current, which was significantly different from the living environment for survival of most marine life. Meanwhile, it was found that the cathode current density and diameter of pipe im- portantly affected the concentration distribution of O2and OH-. The larger the cathode current density and diameter,the larger the con- centration differences of O2 and OH-. Therefore, it showed that the cathode current could restrain the biofouling, and the larger current was, the more difficult for the marine life to attach.