Reducing the concentration of ions in water is increasingly important for drinking water treatment as well as for the treatment of industrial wastewater. In this thesis we analyse the reduction of water conductivity through the diafiltration process using electrodialysis. The basics of electrodialysis and its practical applications are discussed, and the set-up of a laboratory experimental system for the diafiltration process using an electrodialysis cell with a total membrane area of 1280 cm2 is presented. Aqueous solutions with NaCl were used to evaluate the effectiveness of reducing the conductivity of water samples. We monitored the conductivity of the diluate and the current efficiency of the process as a function of the inlet salinity and the voltage on the electrodialysis cell. Depending on the rate of ion removal and the specific mass flux of ions, the power consumption per unit mass of salt was estimated. According to the measured process characteristics, the final part of the thesis also shows the calculations of the diafiltration process for three different salinities and three supply voltages.
|
