english 1. Optimize dissolved air parameters
Precisely control the pressure and temperature of the dissolved air tank, generally maintain the pressure at 0.3-0.5MPa, and maintain the temperature at 20-30℃ to ensure that the solubility of air in water reaches the optimal state. At the same time, reasonably adjust the dissolved air water reflux ratio, usually between 20%-40%, and optimize it according to the influent water quality and treatment requirements to provide enough tiny bubbles and suspended particles to attach.
2. Improve flocculation process
In-depth understanding of the changing laws of influent water quality, accurately select suitable flocculants and coagulants according to different water quality characteristics, and determine the optimal dosage through experiments. For example, for wastewater with high turbidity, polyferric sulfate can be used as a flocculant, and the dosage is controlled at 100-300mg/L; for wastewater containing more organic matter, polyacrylamide can be used as a coagulant, and the dosage is 1-5mg/L. At the same time, optimize the flocculation reaction conditions, such as reaction time and stirring intensity. Generally, the flocculation reaction time is 15-30 minutes, and the stirring intensity is strong at first and then weak, so as to form a good floc structure and improve the flotation effect.
3. Optimize the design and operation of the flotation tank
Reasonably design the structure of the flotation tank, including the water inlet method, water distribution uniformity, water flow rate, etc. Use perforated pipe water distribution or rectifiers to evenly distribute the incoming water in the flotation tank, avoid short-circuit and vortex phenomena, ensure stable water flow, and improve flotation efficiency. In addition, timely adjust the scraping cycle and scraping speed. According to the accumulation of scum, generally scrape once every 2-4 hours. The scraping speed should not be too fast to avoid disturbing the scum layer and causing the separated suspended matter to re-mix into the water.
4. Strengthen equipment maintenance and management
Regularly inspect, maintain and maintain the equipment of Dissolved air flotation systems, including dissolved air tanks, releasers, water pumps, scrapers, etc. Clean impurities and oil stains in the dissolved air tank in time to prevent blockage; check whether the micropores of the releaser are unobstructed, and clean or replace them in time if blocked; ensure the normal operation of the water pump and scraper, extend the service life of the equipment, and ensure the stable operation of the system.
5. Establish a water quality monitoring and feedback mechanism
Real-time monitoring of inlet water quality, outlet water quality and system operating parameters, such as suspended matter concentration, pH value, dissolved air tank pressure, etc. Adjust the operating parameters in time according to the monitoring data to form a closed-loop feedback control.
