Common Treatment Processes for High-Salinity Industrial Wastewater
Evaporation Concentration: This method can effectively remove dissolved solids and organic substances from wastewater, and through the crystallization process, salts can be recovered. However, it has high energy consumption, requires a large amount of thermal energy, has complex equipment, takes up significant space, and the salt crystals produced during the process need to be treated or disposed of subsequently, resulting in higher treatment costs.
Membrane Separation: Membrane separation for desalting is an efficient and environmentally friendly water treatment technology. Its core principle is the selective permeability of semi-permeable membranes, which separates salts and other dissolved substances from the water, achieving desalting. This technology is efficient, energy-saving, and environmentally friendly, capable of removing salts and organic materials from wastewater. It is easy to operate and highly automated. However, membrane materials are prone to fouling and require regular cleaning and maintenance. For wastewater with high salinity, high-pressure pumps are needed to provide sufficient pressure, which leads to higher energy consumption.
Electrolysis: The electrolysis desalting is an effective water treatment technology based on the electrolysis process for removing salts and impurities from water. In the electrolysis desalting system, water is placed in an electrolytic cell, and a voltage is applied to induce electrolysis reactions in the water molecules. The electrolysis reaction converts dissolved solids into precipitates or gases, offering good removal effects and is suitable for treating high-salinity wastewater containing heavy metal ions. The downside is that it has high energy consumption, requires a large amount of electrical energy, and the resulting precipitates or gases need further treatment or disposal.
Biochemical Treatment: The principle of biochemical treatment for high-salinity wastewater is to use the metabolic activity of microorganisms to decompose organic substances in wastewater into harmless substances such as carbon dioxide and water. Through the adsorption, absorption, and transformation activities of microorganisms, salts in wastewater are removed. Common biochemical methods include activated sludge, biofilm, and anaerobic biochemical treatment. In the activated sludge method, microorganisms exist in a suspended state in wastewater, and oxygen is supplied through aeration, allowing microorganisms to carry out metabolic activities under aerobic conditions, degrading organic substances into harmless substances. Meanwhile, microorganisms also adsorb and transform salts in wastewater to achieve salt removal. However, high-salinity environments inhibit microorganism growth and metabolism, requiring dilution before processing, which increases the treatment volume. At the same time, biochemical treatment has a long processing cycle and requires a longer biochemical reaction time.
