QF pressurized dissolved air flotation

QF pressurized dissolved air flotation

overview
Pressurized dissolved air flotation is widely used both domestically and internationally. The master pressurizes the raw water to 0.3~0.4MPa and introduces air to dissolve the air in the water and reach the saturation value at the corresponding pressure state. Then, it suddenly decreases to atmospheric pressure, and the air dissolved in the water is released from the water in the form of small bubbles with a diameter of about Ø 20~Ø 100 μ m. The current basic process includes full inlet pressurized dissolved air flotation, partial inlet pressurized dissolved air flotation, and partial treated water reflux pressurized dissolved air flotation, all of which are composed of basic equipment such as a pressure pump, dissolved air tank, release device, and air flotation tank.
At present, the widely used method is partially treated water reflux pressurized dissolved air flotation. The process flow is shown in the figure. This method refluxes partially treated water (20-50%) and sends it to a pressure dissolved air tank to fully dissolve the air in the water. Then, after passing through a release device, it is mixed with the flocculated raw water and enters the air flotation tank. This method has stable treatment effects and can save a lot of energy consumption, and is widely used in sewage treatment processes.

Characteristics and application scope
Pressure dissolved air flotation has the following advantages:
1. Under pressurized conditions, the solubility of air increases, and there are more bubbles used for gas flotation. Can ensure the effectiveness of air flotation;
2. The dissolved gas undergoes sudden decompression, resulting in not only fine bubbles. Uniform particle size. High density and stable buoyancy, with minimal disturbance to liquids, making it suitable for solid-liquid separation of transported flocs and small particles;
3. The process and equipment are relatively simple, easy to manage and maintain;
4. Especially for partial reflux type, the treatment effect is good, stable, and can save energy consumption.

scope of application
Dissolved air flotation machine is a successful air flotation equipment developed by introducing foreign technology and combining it with China's national conditions and industry characteristics. The air flotation equipment is mainly used in the following aspects:
1. Removal of various heavy metal ions (electroplating mixed wastewater treatment);
2. Oil and water separation for refining and various types of oily wastewater;
3. Removal of oil and color from tannery wastewater;
4. Separation of biofilms after various types of wastewater biological treatment;
5. Mud concentration (with a treatment capacity of 20-30% of the equipment's sewage treatment capacity);
6. Color removal treatment and impurity separation of printing and dyeing wastewater;
7. Removal of algae in water supply engineering;
8. Treatment of wastewater from sausage processing.

Air flotation parameters

Installation size parameter table

model	Processing capacity （m/h）	Dissolved water volume （m/h）	Length L （mm）	Width B （mm）	Height H （mm）	stay time （min）
QF-3	2~3	0.5~1	2200	1500	2300	20~40
QF-5	3~5	1~2	2400	1500	2300
QF-10	5~10	2~3	3400	1500	2500
QF-15	10~16	3~5	3900	2200
QF-20	16~20	5~7	3900	2500
QF-30	20~30	6~10	4900	2800
QF-40	30~40	10~15	6400	2700
QF-50	40~50	15~18	6400	3200
QF-60	50~60	18~20	7400	3300
QF-70	60~70	20~25	7400	3500
QF-80	70~80	25~30	9400	3800
QF-100	80~100	30~35	9400	4200

Outline schematic diagram