AOP advanced oxidation system for treating wastewater with high COD levels, removal rate of 90%–100%

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http://www.25hb.com/data/attachment/forum/201506/04/154202zg8bb1lpbdcld1fg.gif.thumb.jpg The AOP advanced oxidation system for treating wastewater with high COD levels achieves a removal rate of 90%–100%. AOP advanced oxidation system for treating wastewater with high COD levels: 1. Introduction to AOP: Advanced Oxidation Process (AOP) is an advanced chemical treatment method used to remove organic and inorganic substances from wastewater. Organic compounds can be oxidized by four substances: ozone, hydrogen peroxide, oxygen, and air. Their oxidation can also be accelerated by ultraviolet (UV) radiation, ultrasound (US), or special catalytic effects. FILTRA adopts the US-AOP technology developed by the Israeli water purification company AST, which can reduce chemical oxygen demand (COD) by 90% to 100%. Its basis lies in oxidation through free radicals, with the ultrasonic cavitation and catalytic effects induced by metal ion-free radicals accelerating the oxidation process. By precisely pre-programming and customizing the oxidation dosage, sequence, and combined processes, AOP can effectively treat wastewater with high COD concentrations. After being treated by AOP, COD substances undergo mineralization and are converted into stable inorganic substances such as water (H2O), carbon dioxide (CO2), and inorganic salts. AOP is very useful for treating biotoxic or hard-to-degrade substances, such as aromatic hydrocarbon wastewater, pesticide wastewater, and volatile organic compound wastewater. High-concentration chemical wastewater and toxic wastewater can be reused after treatment with AOP. 2. AOP application industries: The US-AOP system is particularly suitable for treating high-concentration organic wastewater that is resistant, toxic, and biodegradable. It can be widely used in industries such as petrochemicals, plastic manufacturing, chemicals, food processing, pharmaceuticals, metallurgy, and textile dyeing. For example: l Treatment of petrochemical wastewater and coking wastewater (COD, turbidity, conductivity, TSS); l Treatment and reuse of wastewater from plastic and resin factories; l Treatment of wastewater from pharmaceutical factories (high-concentration saline COD wastewater); l Treatment of wastewater from milk production (wastewater with high concentrations of BOD, COD, and fats); l Treatment and reuse of wastewater from food processing; l Treatment of wastewater from highway service areas. 3. AOP technology innovation: AOP utilizes oxidants to remove organic substances and oxidizable inorganic substances, completely breaking down organic matter into water and carbon dioxide, thereby reducing the COD and BOD levels in wastewater. As a result, high-concentration organic wastewater can be treated using AOP so that it meets regulatory standards or can be reused. The main technical approaches for AOP include: chemical oxidation using hydrogen peroxide (H2O2); chemical oxidation using ozone (O3); combined oxidation using H2O2 and O3; enhanced oxidation through ultrasound (US) and ultraviolet light (UV), such as US+UV+O3 or US+UV+H2O2; and oxidation accelerated by metal ion catalysts. AST has introduced innovations in AOP technology by adding energy sources such as ultrasound, UV light, or metal ion catalysts to the reaction chamber, thereby generating free radicals (OH• and OH–) that accelerate the oxidation process and enhance its efficiency. This is the most effective method for completely removing all COD components. AST has developed a computer software for performing effective AOP calculations on various COD components. 4. Advantages of AOP: Traditional biodegradation oxidation methods often require high investment and operating costs, and they are not effective at reducing the COD of wastewater. Compounds such as aromatic hydrocarbons, phenols, chlorinated carbohydrates, lipids, and certain proteins generally do not react during biological oxidation processes. Biological treatment methods require long operation periods (up to 48 hours) and very large floor space. Compared to biodegradation and physical degradation, the AST-AOP system offers the following unique advantages: it can handle high-concentration organic wastewater that is resistant to degradation, toxic, or non-biodegradable; it can process wastewater with high COD levels, ranging from 300 ppm to 280,000 ppm. It features high oxidation efficiency, capable of reducing chemical oxygen demand (COD) by 90%–100%, resulting in a COD level of 0–10 ppm after treatment. The system operates automatically, allowing for unattended operation. It does not generate secondary pollutants such as sludge. It has the ability to adjust itself to changes in flow rate and wastewater composition. Its operating costs are low, with results visible within 30 minutes. All AOP by-products are environmentally friendly, enabling the treated wastewater to be discharged in compliance with standards or reused. It requires low power consumption: 300W–1kW (for a treatment flow rate of 1 T/h). In terms of chemicals used, 0.5–1 g of H2O2 is required per gram of COD, while FeSO4 is used in a ratio of 1:10 with H2O2. l Low treatment cost: For example, the treatment cost for wastewater with a COD level of 300 mg/L is less than 3 yuan per ton. 5. Typical components of an AOP system: The GOBO AOP system consists of the following components: l Balanced buffer tank/treated wastewater buffer tank – for storing the treated water; l PLC control system (including HMI) – for controlling the entire system and the AOP process; l UV/US reactor – for enhancing activation and generating free radicals; l UV/US controller – for controlling the operation of the UV/US reactor; l Flow control valves and flow meters – for regulating flow rates; l Metering pumps – for precisely controlling the flow rates of wastewater inlet water and treated water; l Additional membrane systems – such as NFRO – for removing metal ions and enabling wastewater reuse