微电解法降低循环冷却水硬度的试验

Experiment of Hardness Redution of Recirculated Cooling Water by Microelectrolysis

微电解法能够去除水中的成垢离子,降低水质硬度,是处理循环冷却水的一种主动防垢方法。采用单程处理方式处理用自来水与CaCO3、NaHCO3配制的模拟循环冷却水,研究了微电解法处理循环冷却水时去除硬度的特性以及电流密度、极板间距及停留时间3种影响因素对微电解装置去除硬度效果的影响情况。结果表明:当进水硬度保持不变,且运行条件(电流密度、极板间距及停留时间)一定时,微电解装置连续运行300h,硬度去除率基本保持稳定,即其降低硬度的性能不会随时间的延长而发生明显变化;当电流密度为28A/m2、极板间距为5cm、水力停留时间为30min时,微电解装置能较好地降低循环冷却水的硬度,去除率可达42%左右,且极板腐蚀程度较低。

Micro-electrolysis method can remove the scale ions in the water and reduce the hardness of the water. It is an active anti-scaling method for treating circulating cooling water. The single-pass treatment was used to treat the simulated circulating cooling water, and the characteristics of hardness removal and the effect of current density, plate distance and hydraulic residence time on the hardness removal of micro-electrolysis unit were studied in the process of micro-electrolysis treatment of circulating cooling water. The results showed that when the hardness of influent water remained unchanged and operating conditions (current density, plate spacing and residence time) were constant, long-term operation of micro- electrolytic device had little effect on the hardness removal rate, that was, it reduced the hardness. The performance did not change significantly with time. When current density was 28 A/m 2, plate spacing was 5 cm, and hydraulic retention time was 30 min, micro- electrolysis device could reduce the hardness of circulating cooling water better, and corrosion degree of the plate was low.