Abstract:

Electrochemical device with 2D plate electrodes suffers from low softening efficiency in the treatment of circulating cooling water. The precipitation rate of CaCO₃ was improved effectively and the energy consumption was reduced by replacing the 2D plate electrode with a 3D porous nickel foam cathode. It mainly depended on the large electrode area of nickel foam, and providing the large surface in the inner zone of nickel foam for the precipitate crystallization after invactivation. At a current density of 100 A/m² and a flow rate of 0.4 L/min, the obtained precipitation rate was as high as 39.0 g/(m²·h), being 120% higher than that of conventional nickel plate. The deactivated nickel foam cathode was regenerated by current pulsated method after one operational cycle. Because of the incomplete regeneration of the cathode, the average precipitation rate kept decreasing and the energy consumption increased gradually during 10 consecutive cycles. Therefore, it is of great significance to develop an effective regeneration approach for 3D cathode.

Key words: nickel foam, circulating cooling water, electrochemistry, softening, precipitation rate

摘要：

采用具有二维平板电极的电化学软化设备对循环冷却水进行处理，存在软化效率低下的问题。通过将二维电极替换为三维的多孔泡沫镍阴极，有效地提高了CaCO₃的沉淀速率，并降低了能耗。这主要依赖于泡沫镍较大的电极面积以及失活后可为沉淀物结晶提供大量表面的内部区域。当电流密度为100 A/m²，流量为0.4 L/min时，沉淀速率可达39.0 g/（m²·h），相比普通镍板提高了120%。1个运行周期结束后，采用脉冲电流的方法对失活的泡沫镍阴极进行再生。由于阴极再生的不彻底，10个连续周期内平均沉淀速率持续下降，同时能耗不断提高。因此，亟待开发更为有效的适于三维电极的再生方法。

关键词: 泡沫镍, 循环冷却水, 电化学, 软化, 沉淀速率

CLC Number: 

• O646.54