Description
What Is DAF Dissolved air flotation
Dissolved air flotation description
DAF systems are widely recognized for their ability to mitigate issues related to sedimentation and gravity thickening methods. Unlike traditional methods, which often rely heavily on the weight of solids to facilitate separation, dissolved-air flotation relies on the buoyancy provided by air bubbles. This shift in mechanism results in enhanced removal efficiencies, especially in low-density or finely suspended particles. Consequently, DAF has emerged as a preferred choice across various industries, particularly where space is limited or where rapid treatment times are necessary.
Dissolved air flotation principle
Dissolved air flotation (DAF) systems remove suspended solids, fats, oils, greases and non-soluble organics by dissolving air into pressurized water. Here’s how this highly efficient dissolved air flotation process works:
Water enters the WWW™ DAF system through the influent header box to reduce the water’s velocity and distribute it across the length of the vessel. To optimize the treatment process, we design the influent header box with multiple injection points, allowing the introduction of whitewater — a highly saturated pressurized stream of air and DAF effluent that sometimes includes flocculant.
Dissolved air flotation technical sheet
| DAF Model | Qm3/h | Piping Connections | Physical Dimensions(m) | Weight (Kg) | Operating Weight (Kg) |
|---|---|---|---|---|---|
| DAF-003 | 3 |
Inlet: DN50 Outlet: DN50 Sludge: DN100 Vent: DN100 |
L/L1: 3.7/2.8 W/W1: 2.4/1.16 H/H1: 2.2/1.7 |
1500 | 5000 |
| DAF-005 | 5 |
Inlet: DN80 Outlet: DN80 Sludge: DN100 Vent: DN80 |
L/L1: 4/3 W/W1: 2.4/1.16 H/H1: 2.2/1.7 |
1600 | 7000 |
| DAF-010 | 10 |
Inlet: DN100 Outlet: DN100 Sludge: DN100 Vent: DN100 |
L/L1: 4.65/3.8 W/W1: 2.7/1.36 H/H1: 2.4/1.9 |
2000 | 12000 |
| DAF-015 | 15 |
Inlet: DN125 Outlet: DN100 Sludge: DN150 Vent: DN100 |
L/L1: 5.6/4.5 W/W1: 2.9/1.66 H/H1: 2.5/2 |
2200 | 18000 |
| DAF-020 | 20 |
Inlet: DN150 Outlet: DN150 Sludge: DN150 Vent: DN100 |
L/L1: 5.9/4.8 W/W1: 3.2/1.96 H/H1: 2.5/2 |
3000 | 22000 |
| DAF-030 | 30 |
Inlet: DN150 Outlet: DN150 Sludge: DN150 Vent: DN100 |
L/L1: 6.8/5.5 W/W1: 3.2/2.16 H/H1: 2.7/2.2 |
3800 | 32000 |
| DAF-040 | 40 |
Inlet: DN200 Outlet: DN150 Sludge: DN150 Vent: DN100 |
L/L1: 8/6.7 W/W1: 3.6/2.6 H/H1: 2.7/2.2 |
5000 | 45000 |
| DAF-050 | 50 |
Inlet: DN200 Outlet: DN150 Sludge: DN150 Vent: DN100 |
L/L1: 8.4/7 W/W1: 3.6/2.6 H/H1: 2.7/2.2 |
5500 | 55000 |
| DAF-060 | 60 |
Inlet: DN250 Outlet: DN200 Sludge: DN150 Vent: DN100 |
L/L1: 9.9/8.4 W/W1: 3.8/2.8 H/H1: 2.9/2.4 |
6000 | 66000 |
| DAF-070 | 70 |
Inlet: DN250 Outlet: DN200 Sludge: DN150 Vent: DN100 |
L/L1: 10.4/9 W/W1: 3.8/2.8 H/H1: 2.9/2.4 |
6500 | 75000 |
| DAF-080 | 80 |
Inlet: DN250 Outlet: DN250 Sludge: DN150 Vent: DN100 |
L/L1: 10.8/9.4 W/W1: 4/3 H/H1: 2.9/2.4 |
7500 | 100000 |
| DAF-100 | 100 |
Inlet: DN300 Outlet: DN250 Sludge: DN150 Vent: DN100 |
L/L1: 12.1/10.6 W/W1: 4.2/3.2 H/H1: 2.9/2.4 |
9000 | 110000 |
| DAF-120 | 120 |
Inlet: DN300 Outlet: DN250 Sludge: DN150 Vent: DN100 |
L/L1: 12.5/11.4 W/W1: 4.4/3.4 H/H1: 2.9/2.4 |
10000 | 130000 |
Dissolved air flotation process flow
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Chemical Treatment: Wastewater is mixed with coagulants and flocculants to form larger particles ("flocs").
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Air Injection & Contact: Pressurized, air-saturated water is released into the water stream, creating fine bubbles that attach to the flocs.
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Separation: The air-floc aggregates float to the surface, forming a sludge layer.
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Sludge Removal: A surface scraper removes the floating sludge.
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Water Outlet: Clarified water is collected from the bottom of the tank and discharged. Part of it is often recycled to create the pressurized air stream.
Why Choose DAF Dissolved Air Flotation
- Total suspended solids (TSS) reduced by up to 97.
- Chemical oxygen demand (COD) removal rate of up to 60-80%.
- Integrated sludge hopper for easy removal of solid deposits .
- The DAF area provides a static space for the formation of the float.
- Heavy-duty, fully protected, counter-current surface separator that removes surface float.
Dissolved air flotation advantage
Improved Water Quality
Greater turbidity reduction
Discharge compliance
Greater treatment flexibility
Reduced chemical consumption
Operational Advantages
Small footprint
Zero backwash
Improved product quality
Simple and easy operation
Reduced downtime and operational cost
Dissolved air flotation feature
The environmental impact of DAF systems is generally positive, particularly in minimizing water pollution. By enabling the removal of over 90% of harmful components from industrial effluents, DAF systems contribute to cleaner water bodies and reduced environmental pollution. Moreover, reduced chemical usage and advancements in energy-efficient designs further enhance the sustainability of DAF technology.
Dissolved air flotation application
Wastewater TreatmentDissolved air flotation systems are commonly used in the following industries and production processes.
- Petroleum, petrochemical and refineries
- Natural gas processing plants
- Pharmaceutical and cosmetics
- Mining, quarrying and aggregate production
- Water and wastewater treatment
- Food processing
- Commercial and industrial laundry
- Pulp and paper production
- Algae removal and desalination pretreatment
- Pretreatment for downstream biological treatment systems
Conclusion and Summary of Selection Criteria
Choosing a high-efficiency DAF system involves a holistic review that extends beyond simple flow capacity. The optimal system is a balance between hydraulic sizing, optimal chemical pre-treatment, advanced bubble generation, and low operational cost.
| Selection Dimension | Key Criterion for High Efficiency | |
| I. Water Characterization | Thorough pre-treatment and A/S ratio optimization based on testing. |
|
| II. Hydraulic/Mechanical | Low Hydraulic Surface Loading Rate (HSR); High-quality, fine bubble generation. |
HSR at lower end of range; Saturation Pressure ≥ 5 bar; VFD on Recycle Pump; Proprietary Air Release Nozzles. |
|
III. Operations/TCO |
Automation for chemical and flow control; Energy-efficient components; Durable materials. |
|
|
IV. Vendor Support |
Proven track record in your specific industry; Strong performance guarantee. |
Industry-Specific References; Guaranteed Effluent TSS/FOG Limits. |
By meticulously evaluating these four core dimensions, a robust, energy-efficient, and high-performing DAF system can be selected, ensuring long-term environmental compliance and cost-effective operation.
Supplier Information
We are a professional supplier specializing in high-efficiency Dissolved Air Flotation (DAF) systems, offering customized engineering solutions, bench-scale testing services, and robust equipment designed for demanding industrial and municipal applications.
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