The high-efficiency shallow air flotation machine is a breakthrough in dissolved air flotation equipment. It applies the shallow pool principle and the "zero speed" principle, integrating multiple functions such as agglomeration, air flotation, slag scraping, sedimentation, and mud scraping.

High-efficiency shallow air flotation machine working process（Video Description）

How shallow air flotation works ？

The air flotation process mainly relies on the contact, capture, and separation of flocs by microbubbles. Therefore, the design of the contact area and sedimentation area in the air flotation tank significantly impacts the treatment effect.

The "zero speed" principle of shallow air flotation technology realizes the process of equipment movement, and the water body is still.

The flotation tank is circular and has no independent contact and sedimentation areas. Wastewater and dissolved gas water are mixed through pipes and then enter the water inlet pipe in the center of the pool, and then flow out from the water distribution hole through the rotating water distribution pipe and are evenly distributed in the pool for separation and precipitation;

The effluent is collected through a collecting pipe that rotates together with the water distribution pipe (the height of the collecting pipe is located at about 1/2 of the water depth in the pool) and then merges into the drainage pipe in the center of the pool for discharge;

The scum is skimmed off by a drum skimmer that rotates together with the water distribution pipe and water collecting pipe and then flows into the slag discharge pipe in the center of the pool for discharge.

The water distribution pipe has water distribution holes of different densities distributed along the length of the pipe. The direction of the water distribution holes is opposite to the rotation direction of the water distribution pipe. The different density distribution can make the incoming water evenly distributed in the pool. The outflow rate of the water distribution holes is related to the distribution. The rotation speed of the water pipes should be as consistent as possible. This can keep the pool water in a relatively static state, which is conducive to the capture of flocs by microbubbles so that the air-laden flocs can float up at the fastest speed to achieve the purpose of solid-liquid separation.

Application advantages of shallow air flotation technology

(1) The most important feature of shallow air flotation is that during the process of water inflow, water collection, and slag skimming, it overcomes the turbulence and disturbance caused by the moving water body as much as possible, keeping the pool water in a "still" state, creating conditions for the separation of slag and water. It provides the best conditions, which are conducive to the adhesion of microbubbles and flocs, making the particles in the water float or settle nearly static, and the degree of purification is high.

For structural reasons, circular air flotation tanks are rarely used in traditional air flotation. Most of them use rectangular air flotation tanks. The dynamic water flow sequentially passes through the reaction zone, contact zone, separation zone (sedimentation zone), and water collection pipe outlet.

The separation zone is a kind of advection sedimentation, which is not only prone to short flow and bias flow but also cannot avoid hyperpycnal flow caused by temperature difference and density difference, which will affect the sedimentation effect; at the same time when the water collecting pipe collects water from the pool, it will It produces insurmountable hydraulic disturbance and expands the degree of short flow and deflection phenomena.

(2) Shallow air flotation can perform multiple flotations on flocs that do not float to the water surface but fail to settle during one flotation process in the water or that fall back into the water due to disturbance during the skimming of the scum layer. , thereby minimizing the fine floc in the effluent and improving the treatment effect. This is something that traditional rectangular flotation tanks cannot do.

(3) In traditional rectangular air flotation tanks, chain scrapers are usually used to scrape slag. If the scraper moves too fast, it will disturb the sedimentation area too much; if it moves too slowly, the scum layer will be too thick. During the process of being pushed by the scraper, the lower scum will easily break, and the broken scum will become Return the floc to the water.

Shallow air flotation adopts a continuous rotating slag removal system so that the scum accumulated in the upper layer is instantly removed and discharged, causing very little disturbance to the water body, avoiding the re-sinking of floating objects, reducing the load of the air flotation tank, and ensuring the solid content of the slag. Rate.

So, strictly speaking, shallow air flotation uses “skimming” slag, while traditional air flotation uses “scraping” slag.

(4) During the air flotation sedimentation process, since the scum rises very quickly and the separation of slag and water does not require a large water depth, the depth of the shallow air flotation tank is only about 0.6 m, and the HRT is about 3 to 5 minutes. To reduce the impact of water flow disturbance on sedimentation, the effective water depth of traditional air flotation tanks is generally 2.0 to 2.5 m, and the HRT is about 10 to 20 minutes.

Therefore, shallow air flotation not only has a smaller water depth, but also has a much smaller volume. In addition, the bubbles in the traditional air flotation tank cannot evenly fill the entire separation zone, and an "air flotation dead zone" will occur in the rear section of the air flotation tank; while the shallow air flotation tank adopts a circular design, rotating cloth and water collection, so that there is no dead zone in the tank. , ensuring the efficiency and stability of flotation.

(5) The traditional air flotation process has poor adjustment ability, and shallow air flotation can be flexibly adjusted. For example, the height of the water collecting pipe can be adjusted according to the actual operating water depth;

The selection of the rotation period and number of the spiral sludge bucket has a strict matching relationship with the revolution period of the sludge bucket and the thickness of the scum;

The amount of returned water and medicine can also be adjusted according to changes in water volume.

(6) Since the shallow air flotation tank is light and easy to set up during installation, the space under the tank can be reasonably utilized to lay out pipelines and place other required equipment.

Shallow air flotation equipment has high technical requirements. First of all, the water distribution device requires high technical requirements. Since the structure of the air flotation tank is designed to be circular, during the rotation of the water distributor, the water flow velocity in each annular water distribution area changes. Different water distribution pipes must be adjusted to ensure uniform and stable water distribution.

Secondly, the matching degree of angle between the edge of the rotary slag cleaner bucket and the water surface is a technical difficulty. When the edge of the sludge bucket rotates to the lowest point, it needs to remain parallel to the water surface. At the same time, it is also important to control the rotation speed of the sludge bucket. If the rotation speed is too fast, it will increase the disturbance to the water body and increase the moisture content of the scum; if the rotation speed is too slow, part of the scum will settle again.

Therefore, the rotation rate of the slag remover must be adjusted according to the rate of scum floating up, and the height of the sludge bucket must also be adjusted according to the liquid level in the pool so that the slag removal system can operate well.

At the same time, during the operation of the equipment, the water inlet and drainage system of the air flotation equipment should be checked regularly to achieve a balance between the inlet and outlet water; according to changes in the outlet water quality, the dosage, inlet water volume, and dissolved air water volume should be adjusted in a timely manner to ensure the outlet water quality.

Product Advantages

shallow air flotation Advantages

Efficient solid-liquidseparation	The operation is simple	Automatic slag discharge unattended	Realize comprehensive control

Dissolved air flotation technology parameter table

Model	Capacity(m3/h)	Nozzle List(DN)				Dimension(mm)
		Inlet	Outlet	Sludge	Vent	L	L1	L2	W	W1	H
RDAF-002	2	DN50	DN50	DN100	DN50	31800	2200	400	700	700	1600
RDAF-003	3	DN50	DN50	DN100	DN50	4300	3300	500	800	700	1900
RDAF-005	5	DN80	DN80	DN100	DN50	4500	3500	500	1000	700	1960
RDAF-010	10	DN100	DN100	DN100	DN80	5600	4500	500	1200	700	1960
RDAF-015	15	DN125	DN100	DN150	DN80	6100	5000	500	1500	700	1960
RDAF-020	20	DN150	DN150	DN150	DN80	6100	5000	600	1800	700	1960
RDAF-030	30	DN150	DN150	DN150	DN80	7100	6000	700	2000	700	2050
RDAF-040	40	DN200	DN150	DN150	DN80	8100	7000	900	2200	700	2050
RDAF-050	50	DN250	DN150	DN150	DN80	8100	7000	1000	2700	700	2050
RDAF-060	60	DN250	DN150	DN150	DN80	9100	8000	1000	2800	700	2050
RDAF-070	70	DN250	DN150	DN150	DN80	10100	9000	1000	3000	700	2050
RDAF-080	80	DN250	DN150	DN150	DN100	11100	10000	1200	3200	700	2050
RDAF-090	90	DN250	DN150	DN150	DN100	11600	10500	1200	3200	700	2050
RDAF-100	100	DN300	DN150	DN150	DN100	11600	10500	1200	3600	700	2050

Model	Capacity(m3/h)	Weight(Kg)	Operating Weight(Kg)	Power
				Reflux Pump	Air Compressor(kw)	Skimmer(kw)	Agitator(kw)
RDAF-002	2	1300	4000	0.55	0.55	0.1	0.1
RDAF-003	3	1500	5000	0.75	0.55	0.1	0.1
RDAF-005	5	1600	7000	1.1	0.55	0.1	0.2
RDAF-010	10	2000	12000	1.5	0.75	0.2	0.2
RDAF-015	15	2200	18000	2.2	0.75	0.2	0.4
RDAF-020	20	3000	22000	2.2	0.75	0.2	0.4
RDAF-030	30	3800	32000	3	1.5	0.2	0.4
RDAF-040	40	5000	45000	5.5	1.5	0.2	0.4
RDAF-050	50	5500	55000	7.5	1.5	0.4	0.4
RDAF-060	60	6000	66000	7.5	1.5	0.4	0.4
RDAF-070	70	6800	85000	11	1.5	0.4	0.75
RDAF-080	80	7500	100000	11	1.5	0.4	0.75
RDAF-090	90	8300	105000	11	1.5	0.4	0.75
RDAF-100	100	9000	11000	15	2.2	0.4	0.75

Dissolved air flotation outline drawing

1. Air dissolving system	2. Main Tank	3. Electric control cabinet	4. Chemical reaction tank
5. Micro-bubble releaser	6. Skimmer system	7. Returning line	a. Raw water inlet pipe
b. Clean water outlet pipe	c. Foam discharge pipe	d1. Reaction area vent pipe	d2. Vent tube in contact area
d3. Separate area vent pipe

DAF Accessories list

Parts Name	Accessories Pictures	Parts Name	Accessories Pictures
Chain		Float level switch
Releaser		Pressure Gauge
Rubber Scraper		Chain wheel

Product Details

Dissolved air flotation product details

Effectiveness of equipment

Dissolved air flotation Effectiveness of equipment

Cooperation Case

Environmental Protection Technology City Industrial Wastewater Treatment Plant Project

More cases are being updated continuously. . .

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