The advantages of heterogeneous ozone catalytic oxidation process applied to the treatment of industrial high-salt wastewater
At present, the treatment status of high salt wastewater is the coexistence of many technologies, but each has advantages and disadvantages. Traditional treatment methods such as distillation desalting, although mature technology, but high energy consumption, high operating costs, and difficult to adapt to large-scale treatment needs. With the improvement of environmental awareness and the continuous development of wastewater treatment technology, a variety of treatment technologies are integrated into the development trend of high-salt wastewater treatment. By optimizing the combination of different treatment technologies, with ozone catalytic oxidation as the core process to achieve effective treatment of high-salt wastewater, while reducing treatment costs, to achieve a win-win situation of economic benefits and environmental benefits.
In many wastewater treatment technologies, heterogeneous ozone oxidation technology has attracted much attention for its strong oxidation capacity, no chemical sludge and no secondary pollution. It has a good degradation effect on refractory pollutants, and is an advanced oxidation technology widely used in wastewater treatment. Direct ozone oxidation has a low ozone utilization rate and low ·OH production rate, and the exclusive ozone catalyst of Cori is used to efficiently degrade organic pollutants by promoting ozone to produce active oxygen species such as hydroxyl radical (•OH), superoxide radical (•O2−) and singlet oxygen (1O2).
1. Principle of advanced ozone oxidation technology
Ozone (O) is a strong oxidizing gas, which can react with pollutants in wastewater through direct and indirect oxidation. Direct oxidation refers to the direct reaction of ozone molecules with pollutants to convert them into small molecules. Indirect oxidation is the oxidative species such as hydroxyl free radicals (·OH) generated by ozone decomposition, which further oxidizes and degrades organic matter, and even mineralizes it into carbon dioxide and water. As the best oxidant in advanced oxidation, hydroxyl radical has the characteristics of non-selectivity and high reactivity, and can rapidly degrade refractory organic matter in wastewater.
2. Application advantages of advanced ozone oxidation technology
(1) Efficient treatment: advanced ozone oxidation technology can efficiently degrade organic pollutants in wastewater, reduce chemical oxygen demand (COD) and chroma, and improve the biodegradability of wastewater.
(2) Environmental protection without secondary pollution: the final product produced in the ozone oxidation process is carbon dioxide and water, which will not introduce new pollutants and meet environmental protection requirements.
(3) Strong adaptability: ozone oxidation is not affected by the salt concentration of wastewater, and can maintain strong oxidation in a high-salt environment, which is suitable for the treatment of high-salt wastewater.
(4) Versatility: In addition to degrading organic matter, ozone can also remove odors, odors, and metal ions such as iron and manganese in water to improve water quality.
3. Kolisu heterogeneous ozone catalytic oxidation treatment of high salt wastewater
Compared with traditional technologies, advanced ozone oxidation technology has shown significant advantages in treatment efficiency, reaction conditions, ease of operation and cost effectiveness, and more importantly, the technology avoids secondary pollution and can improve the salt recovery rate of high-salt wastewater, which fully meets the requirements of current environmental protection policies and standards.
The principle of ozone oxidation process to improve the salt recovery rate of high-salt wastewater mainly involves the following aspects:
(1) Oxidative decomposition of organic matter: ozone, as a strong oxidizing agent, can effectively oxidize and decompose organic matter in high-salt wastewater, converting it into harmless carbon dioxide and water, thereby reducing the chemical oxygen demand (COD) of wastewater. This process helps to reduce organic pollutants in wastewater and improve the efficiency of wastewater treatment.
(2) Improvement of flocculation effect: In the treatment of high-salt wastewater, because the wastewater contains a large number of soluble inorganic salts, such as Cl−, Na+, SO42−, Ca2+, etc., these salts have a significant inhibitory effect on conventional biological treatment. Ozone oxidation technology can effectively improve this situation, through oxidation to change the nature of suspended solids in water, so that suspended particles in water become larger. This helps to improve salt recovery while reducing the amount of flocculants used and reducing the amount of chemicals consumed.
(3) The application of catalytic ozone oxidation: in some cases, the oxidation efficiency of ozone is improved by adding a catalyst (such as Fe/Al2O3). The catalyst can promote the decomposition of ozone and produce more hydroxyl radicals, thus improving the oxidation efficiency of organic matter. However, it is important to note that certain components of the wastewater, such as silicates, may cause the catalyst to be deactivated, affecting the catalytic oxidation efficiency of the overall process.
(4) Optimization of ozone oxidation process: In practical applications, by optimizing the ozone oxidation process, such as adjusting the ozone flow rate, pH value and reaction time, the treatment effect of high-salt wastewater can be further improved. For example, by adjusting the ozone flow rate and reaction time, the COD value of the wastewater can be effectively reduced.
(5) The use of heterogeneous ozone catalysts: In some high-salt wastewater treatment projects, heterogeneous ozone catalysts are used to further improve ozone removal efficiency. The use of this catalyst can improve the utilization of ozone, which can more effectively remove organic matter from wastewater and improve salt recovery.
(6) ozone-hydrogen peroxide coupling catalytic oxidation: In some cases, the combined use of ozone and hydrogen peroxide can further improve the removal effect of COD. Selecting suitable catalyst and pH conditions, this method shows the advantages of high efficiency, economy and wide application range in practical application, especially for the treatment of industrial wastewater containing refractory organic matter and high salinity.
The application of ozone oxidation technology in the treatment of high-salt wastewater can not only improve the recovery rate of salt, but also effectively reduce the pollution load of wastewater and reduce the impact on the environment. With the continuous progress and optimization of technology, it is expected that ozone oxidation technology will be more widely used in the field of high-salt wastewater treatment, and provide new impetus for the development of environmental protection industry. It is worth emphasizing that the successful application of advanced ozone oxidation technology is highly dependent on the development and application of efficient catalysts. Optimization of catalyst selection and preparation process is of vital significance for improving ozone utilization, enhancing oxidation efficiency and ensuring the stability and reliability of the treatment process.
