NS-V Type Integrated Air Flotation Unit

NS-V Type Integrated Air Flotation Unit

I. Advantages

Although the working principle of the "NS-V Type Integrated Air Flotation Unit" is fundamentally similar to other air flotation systems, it features significant structural innovations and offers the following advantages:

Equipment Integration

Conventional air flotation systems typically consist of separate components including flotation tanks, chemical dosing equipment, dissolved air tanks, dissolved air water pumps, air compressors, and sewage pumps. This results in longer installation times, inconvenient management, and large space requirements. The YF air flotation unit integrates these separate components organically into a single system. For wastewater requiring only pH adjustment, it can be put into operation immediately upon connecting the inlet and outlet pipes, without the need for foundation construction.

Automated Operation

Once the NS-V type air flotation unit is properly adjusted, it operates automatically without requiring dedicated personnel for normal operation, achieving an unmanned management state.

II. Scope of Application

1. For heavy metal ions in electroplating wastewater, such as zinc, copper, lead, etc., with total content below 50 ppm, the removal rate can exceed 70%.

2. For printing and dyeing wastewater, the color removal rate reaches about 90%, COD removal rate about 60-70%, and BOD removal rate about 50%.

3. For food processing, slaughterhouse, and tannery wastewater, the COD removal rate is about 70%, and suspended solids removal rate about 90%.

4. For oil in refinery wastewater, it can be reduced to below 10 mg/L, achieving clarified water quality.

5. For chemical wastewater and pigment paint wastewater, the COD removal rate is 74%, and color removal rate about 93%.

6. For papermaking white water, fiber recovery rate can reach about 95%, COD removal rate about 86.7%, with clear water fully reused.

7. For large bathing pools, turbidity can be stabilized below 10 degrees, with a significant reduction in bacteria.

8. For domestic drinking water and industrial water, turbidity can be purified to below 5 degrees, with good effects on reducing color and oxygen consumption.

III. Working Principle

The working principle of the air flotation unit involves dissolving a large amount of air into water under certain conditions to form dissolved air water, which serves as the working medium. Through a release device, the pressure is suddenly reduced, rapidly releasing a large number of fine bubbles that adhere to the "floc" formed after coagulation in the wastewater. This causes the flocs to float, rapidly removing pollutants from the water and achieving water purification.

IV. Process Description

The NS-V type air flotation unit consists of four parts:

(1) Chemical dosing and coagulation section,

(2) Reflux water dissolution and release section,

(3) Air flotation section,

(4) Electrical control section.

(1) Chemical dosing and coagulation section:

Wastewater is pumped from the wastewater tank to the vortex reactor by a sewage pump. Chemical dosing is generally performed before the sewage pump, allowing the chemicals and wastewater to mix thoroughly through the rotation of the pump's impeller. Chemicals are supplied by the dosing device. The dosed wastewater enters the vortex reactor, where full coagulation is achieved. (Other coagulation methods can be adopted if required by the user.)

(2) Reflux water dissolution and release section:

The effectiveness of air flotation primarily depends on the dissolution and release of reflux water. This unit uses high-efficiency, energy-saving dissolution and release equipment. Compressed air from the air compressor and treated reflux water pressurized by the water pump are fully mixed and dissolved in the dissolution tank to form dissolved air water. The working pressure of the dissolution tank is generally 2-3.5 kg/cm².

(3) Air flotation section:

The coagulated wastewater enters the air flotation tank. The dissolved air water from the dissolution tank is suddenly减压 (pressure reduced) at the lower part of the inlet and outlet pipes by the dissolved air release device, releasing a large number of micro-bubbles. These micro-bubbles rise and encounter the coagulated suspended solids in the wastewater, adhering to them and causing them to float quickly. Thus, all treated suspended solids float to the surface. They are then skimmed off by the surface skimmer at the top of the air flotation unit and discharged into the sludge tank, while the treated clear water is discharged from the bottom of the tank.

(4) Electrical control section:

The unit is equipped with an electrical control cabinet. After调试 (debugging) and installation, it can operate unattended. The control cabinet manages the operation of the water pump, skimmer, and air compressor.