埕岛海区钢铁阴极保护参数研究

于1989年9月开始，在山东省胜利油田胜利设计院化学研究室，对A₃钢的保护参数进行研究。实验介质为现场采集的黄河入海口附近的含悬浮泥沙的新鲜海水。实验在动水（1.5m／s），静水和动静水交替三种模拟状态下进行。控制保护电位为-800，-900，-1000mV（Ag／AgCl），研究在上述状态下和不同电位下的保护度，最大冲击保护电流密度及稳定的保护电流密度。结果表明，在三种保护电位下，A₃钢的保护度都在90％以上，可以达到防腐目的。在不同的模拟状态下，保护电流密度变化较大，其稳定值在动水状态下为2000－2500 mA/m2，在静水状态下为85 – 120 mA/m²，在动静水交替下为70 - 400 mA/m²。最大冲击保护电流密度（动水状态，保护电位为-1000 mV）接近30 A/m²。

STUDIES ON CATHODIC PROTECTION PARAMETER IN CHENGDAO SEA

The Chengdao Sea zone located near the Huanghe River Mouth is characterized by high current `velocity (max. 1.5 m/s) and high silt content (max. 0.93 kg/m³ in the surfacial water, 1.24 kg/m² in the bottom water). The cathodic protection design parameter under these conditions may be different from that used in common practice. To design a cathodic protection system for marine oil platform, wharf steel pile, steel pipeline etc. in this sea zone, the cathodic protection current density was studied under stir, stirless, and alternate stir-stirless conditions and three potentials; -800, -900, -1000 mV (Ag/AgC1) in laboratory with fresh silt seawater taken from the sea zone. The results show that the protection rates are all over 90% under the above three conditions and potentials,' good enough for anti-corrosion. In different condition, the protection current densities varied considerably, being 2000 - 2500 mA/m², 85 - 120 mA/m², and 70 - 400 mA/m² under stir, stirless, and alternate stir-stirless conditions when potential were between -800 and -1000 mV.