Study on trial for making a continuous-type electroosmotic dewatering apparatus of solid-liquid mixutures under an electric field applied efficiently

研制了一种电渗透脱水实验装置，该装置可以连续去除在两个垂直圆柱形电极之间的通道中重力流下的浆料中的水分。脱水体基本由三个垂直的长圆筒组成，两个多孔不锈钢板各组成一个锥形长圆筒，两个圆筒分别作为电极和过滤介质。为了使浆液与电极保持良好的接触，在电极筒之间向下流动的浆液自然施加液压压缩压力。同时在浆料上施加直流电场或电极极性周期性反转的交流电场。然后将浆液水平脱水到两个圆柱形电极的内外。将粉末颗粒与去离子水混合制备浆料。浆料在浆槽内搅拌均匀后，由浆泵送入上述脱水体。对脱水体内向下流动的矿浆施加连续直流电场、电极极性一次反转的直流电场和改变频率和波形的交流电场。利用该连续式电渗透脱水装置，通过改变施加电压、浆料、浆料进料进行了实验研究。实验研究结果总结如下：1。对于几乎不受重力脱水的膨润土浆料，直流电场作用下的浆料几乎只脱水到圆柱形电极的外侧。另一方面，将电极极性反转的直流电场作用下的矿浆分别向电极内外进行一次脱水，排水量较连续直流电场增大。在交流电场作用下，无论正弦波形还是矩形波形，排水流量都随频率的降低而增大。电极内外的排水流量基本相同，交流操作能有效地实现电渗透脱水。少

An experimental apparatus for electroosmotic dewatering which can remove continuously the water in slurry flowing down gravitationally in a passage between two vertical cylindrical electrodes was made for trial. The dewatering body basically consisited of triple vertical long cylinders, and two porous stainless-steel plates were each formed long tapering cylinders and both of the cyliders were used respectively as electrodes and filter media. Hydraulic compressive pressure was naturally applied to the slurry flowing downwards between the electrode cylinders, in order to keep well contact between the slurry and the electrodes. A D.C.electric field or an A.C.electric field with periodical reversals of electrode polarity was applied to the slurry by an electric supplier at the same time. Then the slurry could be dewatered horizontally to both inside and outside of the two cylindrical electrodes. Slurry was prepared by mixing powder particles and deionized water. The slurry was agitated in … More a slurry tank to homogenize, and then the slurry was fed to the above-mentioned dewatering body by using a slurry pump. Electric fields such as continuous D.C., D.C.with reversing electrode polarity once, and A.C.with changing frequency and wave form were applied to the slurry flowing downwards in the dewatering body. Using this continuous type electroosmotic dewatering apparatus, experiments were performed by changing applied voltage, slurry material, and slurry feed. The results obtained by the experimental investigations are summarized as follows :1. For bentonite slurry whichi was hardly dewatered gravitationally, the slurry under D.C.electric field was dewatered alomost only to the outside of cylindrical electrode. On the other hand, the slurry under D.C.elecric field with reversing electrode polarity once was dewatered to both inside and outside of the electrodes, and then the flow rate of drained water was increased compared with the continuous D.C.electric field.2. In the case of A.C.electric fields, the flow rate of drained water showed a tendency to increase with decreasing the frequency, regardless of wave forms such as sine and rectangular. The drained flow rates to the inside and outside of electrodes were almost the same respectively, and A.C.operation gave an effective electroosmotic dewatering in this apparatus. Less