Air flotation machine

Equipment introduction

Dissolved air flotation (DAF) technology has been widely used in water supply and drainage, as well as wastewater treatment, in recent years. It effectively removes difficult-to-settle, floating flocs from wastewater. It boasts high processing capacity, high efficiency, minimal footprint, simple operation, and a wide range of applications. It is widely used in a variety of wastewater treatment processes, including petroleum wastewater treatment, chemical wastewater treatment, papermaking wastewater treatment, refinery wastewater treatment, oily wastewater treatment, leather wastewater treatment, steel wastewater treatment, food wastewater treatment, starch wastewater treatment, slaughterhouse wastewater treatment, laundry wastewater treatment, and soy product processing wastewater treatment. Dissolved air flotation plays a vital role in wastewater treatment.

Equipment advantages

1. Large treatment capacity, high efficiency, and minimal footprint.

2. Simple process and equipment structure, easy to use and maintain.

3. Eliminates sludge bulking.

4. Dissolved air flotation introduces aeration into the water during flotation, significantly removing surfactants and odors. Aeration also increases dissolved oxygen in the water, creating favorable conditions for subsequent treatment. It effectively reduces the load on the biochemical unit in the wastewater treatment process and plays a crucial role in improving COD and BOD removal rates.

5. Flotation is highly effective for low-temperature, low-turbidity, and algae-rich water sources.

Working principle

Dissolved air flotation uses a new, highly efficient dissolved air device—a microbubble generator—to dissolve air into the water, replacing traditional air entrainment equipment. Several inclined tube groups are installed within the flotation area, including a housing, scraper, and spiral discharger, forming a complete flotation water purification system. Theoretically, the flotation treatment effect is not directly related to the residence time, but only to the flotation area. If the flotation area at a water depth of H is reduced to H/10, the flotation distance and residence time will be reduced tenfold. This is the famous "shallow pool theory."
The purpose of adding inclined tubes to the flotation zone is to increase the flotation area, significantly reducing the Reynolds coefficient and preventing turbulent flotation. Instead, it creates a laminar flow, achieving shallow flotation. Similarly, when the density of suspended solids is greater than 1, the installation of the inclined tubes creates a shallow pool sedimentation effect, allowing sedimentation to occur under turbulent conditions. Pollutants with larger particle size and higher specific gravity that are less likely to float are concentrated in the sludge collection area, achieving the goal of water purification.

Scope of application

1. Suitable for industrial wastewater and municipal sewage from industries such as papermaking, petroleum, chemical industry, printing and dyeing, leather, electroplating, starch processing, hospitals, pharmaceuticals, domestic sewage, electricity generation, brewing, coatings, and dairy processing.

2. Can also be used for advanced treatment after biochemical treatment.

Process flow chart