碳钢海水工业冷却器的腐蚀控制技术

CORROSION-CONTROL TECHNIQUE OF CARBON STEEL SEAWATER COOLING APPARATUS

应用电化学联合保护新技术 ,通过冷却管管内保护电位与保护电流测量 ,研究静止与流动海水中管内保护电位变化 ,保护电位与保护电流随时间变化以及管径与海水流速对管内保护电位的影响。冷却管 11个月平均保护电流密度约 0 .4m A/ m2 ,11个月后冷却管 (管内径 19m m,长 3m)管内远端保护电位为 - 940 m V(相对于 Ag/Ag Cl参比电极 )。实现冷却管 (管内径 19mm)内保护距离从以前的 0 .3m提高到 3m以上 (单端 )。经过近一年的模拟实验 。

Internal surfaces of carbon steel cooling tubes of 14, 16, 19 mm ID in stagnant and flowing seawater were protected by a new kind of corrosion control technique Through monitoring the protection potential and current, the changes of the protection potential and current vs time and the effects of the diameter of tubes and the flow rate of seawater on the potential of internal tube surfaces were studied The mean protection current density of internal tube surfaces for 11 months was about 0 4mA/m 2 After 11 months, the protection potential at the remote end of cooling tubes from the anode was -940mV (vs Ag/AgCl reference electrode) The results showed that the protection distance of internal surfaces of cooling tubes (19mm ID) increased to above 3m from the former 0 3m (from the single end) One year experiment showed that the cooling tubes were nearly the same as that before the experiment