膜电解法用于循环冷却水处理

Membrane electrolysis used in circulating cooling water treatment

在传统微电解反应器基础上增加离子膜并用于处理循环冷却水。由于离子膜的存在,反应器阴极室内能够快速富集OH^(-),有利于去除Ca^(2+)和Mg^(2+),同时阳极室内电解产生的Cl2溶于水生成的次氯酸盐可作为杀菌剂使用。探究了离子膜类型、电流密度、水力停留时间、极板间距等参数对循环冷却水硬度去除率和比能耗的影响,并探究了阳极室NaCl浓度对除硬效果、比能耗和阳极副产物的影响。结果表明,使用阳离子膜的反应器,在进水硬度为500 mg/L(以CaCO_(3)计)、电流密度为25 A/m^(2)、水力停留时间为14 min、极板间距为12 mm、阳极NaCl质量分数为4%、电解时间为6 h的条件下,硬度去除质量浓度为466 mg/L,硬度去除率为93.2%,比能耗为3.69 kW·h/kg,阳极液有效氯质量浓度为3.99 g/L。相比常规微电解法,膜电解法提高了循环冷却水的硬度去除率和电流效率,同时阳极液可以作为杀菌剂使用,提高了经济效益。

Ionic film was added to the traditional microelectrolytic reactor and used to treat circulating cooling water.Due to the existence of the ionic membrane,OH^(-) could be rapidly enriched in the cathode chamber of the reactor,which was conducive to the removal of Ca^(2+) and Mg^(2+).The chlorine produced by electrolysis in the anode chamber was dissolved in water to generate hypochlorite,which could be used as a fungicide.The effects of ionic film type,current density,hydraulic retention time,plate spacing and other parameters on hardness removal rate and specific energy consumption of circulating cooling water were explored,and the effects of NaCl concentration in anode chamber on hardness removal effect,specific energy consumption and anode by-products were also explored.The results showed that the hardness removal mass concentration,removal rate,specific energy consumption and effective chlorine concentration of the anodic solution was 466 mg/L,93.2%,3.69 kW·h/kg and 3.99 g/L under the condition of using cationic membrane reactor,500 mg/L(CaCO_(3))of inlet water hardness,25 A/m^(2) of current density,14 min of hydraulic retention time,12 mm of distance between the plates,4%of NaCl concentration of anode,and 6 h of electrolysis time.Compared with the conventional microelectrolysis method,the membrane electrolysis method can improve the hardness removal rate and current efficiency of circulating cooling water,and the anodic liquid can be used as a fungicide,which improves the economic benefits.