Technological Scheme of Electroplating Industry Wastewater Treatment using Electromembrane Separation Methods

Negative environmental impacts are becoming more and more significant each year. Electroplating production is one of the largest sources of environmental pollution due to the high content of pollutants in its wastewater. Zinc, nickel, copper, and chrome coatings are most often used in electroplating production; therefore, as a result of the production process, alkaline, acidic, and other forms of wastewater contamination occur. To prevent environmental pollution by industrial solutions and wastewater of electroplating industries, it is possible to use electrodialysis purification. Historically, electrodialysis developed as a desalination method, but recently it has also been used for wastewater separation. The main advantages of electrodialysis are the low cost of cleaning, simplicity of operation, and the lack of the necessity of additional chemicals. In the work, experimental data are obtained on the purification level of an initial solution from Cu2+, Fe3+, and Ni2+ cations. Analysis of the experimental data allows us to establish that the separation process at a current density of 20 A/m2 is most advantageous in terms of energy efficiency among the studied separation modes. This separation mode provides almost the maximum purification level with relatively low energy consumption. Based on the selected current density, the economic efficiency of the proposed technological scheme of industrial solution and wastewater purification of electroplating production with a monthly volume of 10 000 m3 is estimated. Calculations show that the cost of cleaning of 1 m3 of wastewater according to the proposed technological scheme is more profitable than the cost of wastewater discharging, even without considering the conservation of water resources. The indicators of the profitability index (PI = 2.3) and the payback period (PP = 4 years and 4 months) allow us to conclude that the project of implementing the proposed technological scheme for cleaning industrial solutions and wastewater of electroplating production is cost-effective and can be profitably implemented in practice.