Aquaculture wastewater is mainly composed of organic wastewater. Due to its high influent concentration, it is difficult to treat wastewater using a single process. It is recommended to use a combination of multiple processes. Among them, the dissolved air flotation machine utilizes the different solubility characteristics of water at different pressures to generate microbubbles in the water through pressurization. These microbubbles can adsorb and float suspended substances (such as feed residues, solid particles in animal feces), oils, and organic matter in wastewater, thereby achieving solid-liquid separation of wastewater.
The application of dissolved air flotation machine in aquaculture wastewater is very extensive, and its effective and environmentally friendly characteristics make it one of the main equipment for aquaculture wastewater treatment.
1、 Main structure of dissolved air flotation machine
The dissolved air flotation machine mainly consists of four parts: dissolved air system, release system, separation system, and slag scraping system.
1. Dissolved air system: The air sent to the air tank by the air compressor is brought into the dissolved air system through the jet device. Under pressure, the air is forced into the water to form dissolved air water.
2. Release system: When dissolved water and wastewater meet in a specific environment, countless tiny bubbles are generated.
3. Separation system: The microbubble group is in full contact with the suspended solids in the wastewater being flocculated after dosing, and adsorbs onto the flocculated suspended solids during the slow rise process, helping them easily float to the water surface in the separation system and form floating slag.
4. Scraping system: The scraper removes the floating slag and achieves solid-liquid separation.
2、 Application advantages
1. Effective solid-liquid separation: The dissolved air flotation machine generates a large number of tiny bubbles, causing suspended solids in aquaculture wastewater to adhere to the bubbles, thereby achieving rapid solid-liquid separation. This effective separation process helps significantly improve processing efficiency, reduce processing time and costs.
2. Automated control, simple operation: Modern dissolved air flotation machines are usually equipped with automated control systems that can monitor and adjust the processing process in real time. This not only reduces the difficulty and cost of manual operation, but also avoids safety hazards caused by human errors.
3. Effective removal of recalcitrant organic matter: Aquaculture wastewater is rich in many recalcitrant organic matter, and the dissolved air flotation machine can not only remove suspended solids, but also remove some recalcitrant organic matter, reducing the burden for subsequent treatment.
4. Improve water quality and reduce pollution: The concentration of pollutants in aquaculture wastewater treated by dissolved air flotation machine is significantly reduced, and there will be no secondary pollution, which meets environmental protection requirements. At the same time, the filtered floating slag can also be reused, such as being used as organic fertilizer through dehydration, drying, and other methods, to achieve resource recycling.
5. Small footprint: The dissolved air flotation machine has a compact structure and a small footprint, making it suitable for use in places with limited space such as breeding farms.
3、 Application Fields
In addition to treating aquaculture wastewater, dissolved air flotation machines are widely used in various fields such as papermaking, municipal wastewater, chemical industry, beverage industry, printing and dyeing industry, oil refining industry, electroplating industry, food industry, textile industry, etc.
In summary, the application of dissolved air flotation machines in aquaculture wastewater has significant advantages and broad prospects. It can not only effectively remove suspended solids, oils, and organic matter from wastewater, but also improve water quality, reduce pollution, and bring certain economic benefits. Therefore, promoting and applying dissolved air flotation machines in the treatment of aquaculture wastewater is of great significance.
