Green and efficient treatment of wastewater containing heavy metal is greatly desired. Thus, in thisstudy, membrane-free electrodeionization, which allows the electrical regeneration of the packed resinswithout the use of membranes and chemicals, was performed for the removal of nickel ions fromwastewater. In this MFEDI system, an improved stack configuration was used to prevent nickelhydroxide precipitation and phosphonic acid resin was adopted for adjusting the pH to neutral. Theoperation parameters (including current density, flow rate during electrical regeneration, and initialnickel concentration) were evaluated in relation to the electrical regeneration of the exhausted resins, thewater recovery ratio as well as the energy consumption. The results showed that, the increase of currentdensity and flow rate resulted in better electrical regeneration effect, while the initial nickel concentrationhad no obvious influence on this process. Their optimal values for energy consumption and waterrecovery ratio were as follows: current density of 300 A/m 2 , flow rate of 10.6 L/h, and initial nickelconcentration below 10 mg/L. Under these conditions, the water recovery ratio, energy consumption,pH of the concentrate stream, and conductivity of the dilute stream were, respectively, 87.5%, 4.0kWh/m 3 , 5.9–7.5, and below 0.3 μs/cm.
展开▼
机译：迫切需要绿色高效地处理含重金属的废水。因此，在本研究中，进行了无膜电去离子，该电离能使填充的树脂在不使用膜和化学药品的情况下进行电再生，以去除废水中的镍离子。在该MFEDI系统中，使用了改进的堆叠结构来防止氢氧化镍沉淀，并采用了膦酸树脂将pH值调节至中性。相对于废树脂的电再生，水的回收率以及能耗，评估了运行参数（包括电流密度，电再生期间的流量和初始镍浓度）。结果表明，电流密度和流速的增加导致更好的电再生效果，而初始镍浓度对此过程没有明显影响。它们的能量消耗和水回收率的最佳值如下：电流密度为300 A / m 2，流速为10.6 L / h，初始镍浓度低于10 mg / L。在这些条件下，水的回收率，能量消耗，精矿流的pH和稀流的电导率分别为87.5％，4.0kWh / m 3，5.9-7.5和低于0.3μs/ cm。
展开▼
