DAF Coagulant
What Makes DAF Systems Effective
If your facility relies on dissolved air flotation (DAF), you’re already familiar with its edge over traditional sedimentation for separating solids, oils, and grease. But what many operators don’t realise is just how much of that performance depends on the chemistry applied upstream. At Tanafloc, we see it all the time: even the most advanced DAF unit underperforms when the coagulation step is poorly managed.
DAF works by dissolving compressed air into water, then releasing it under atmospheric pressure to generate a cascade of fine bubbles. These bubbles attach to suspended matter, lifting it to the surface for skimming. But the success of this process hinges on surface charge and soluble chemical oxygen demand, two factors that coagulants directly influence.
That’s where we come in. Tanafloc natural coagulants help optimise particle charge and reduce sCOD, setting the conditions for efficient, reliable flotation. In short, if you want your DAF system to run as designed, the chemistry needs to be right. We make sure it is.
How Coagulants Enhance the DAF Process
In DAF systems, separation is not about gravity. It is about flotation, and flotation requires bonding. Solid particles in raw wastewater typically carry a negative surface charge, which keeps them suspended. Coagulants neutralise that charge, allowing particles to aggregate into larger flocs and increasing the chances of air bubble attachment, which is crucial for removing pollutants.
Without this neutralisation, bubbles fail to bind effectively. This leads to incomplete removal, higher turbidity, and excessive recirculation. Using the right coagulant improves air adhesion, enhances float sludge recovery, and ultimately produces treated water that meets discharge limits.
The dissolved air flotation system depends on stable floc formation. The faster flocs form, and the more compact they are, the better your DAF tank performs, leading to improved water quality. This is particularly true at higher flow rates or under chemical oxygen demand (COD) stress, where the ability to remove solids becomes critical.
Inside the Chemistry: What You're Actually Adding
DAF units are highly responsive to changes in charge dynamics. Selecting your chemical inputs based solely on cost or habit often leads to increasing operating costs and diminishing returns, sometimes requiring more energy to maintain performance.
Conventional choices include:
- Ferric chloride: Low-cost and effective on high-turbidity wastewater, but corrosive and sensitive to pH changes.
- Aluminium sulphate (alum): Broadly used in water treatment, though less efficient at lower temperatures or when removing soluble silica.
- Monomeric aluminium salts: Common in drinking water treatment, although slower acting in high-strength industrial wastewater.
In contrast, tannin-based coagulants like Tanfloc deliver comparable charge neutralisation without the drawbacks of residual metals, scaling or acidic runoff, making them superior to traditional methods. Made from plant-derived biopolymers, they support floc growth while maintaining pH stability and reducing sludge volume. That means less impact on your sludge dewatering unit and reduced polymer demand. These formulations also outperform metal salts when targeting emulsified oils and fine colloidal particles in food, beverage and dairy wastewater.
Performance Benefits of Tanfloc in DAF Applications
Tanafloc Australia’s natural coagulant technology is engineered specifically for DAF applications where surface separation must perform well under variable load conditions. It is particularly effective in treating higher concentrations of various contaminants:
- High organic loads from meat and poultry plants
- High-fat influents from dairy processors
- Coloured wastewater from paper mills and textile dye houses
By using larger molecules with high cationic activity, Tanfloc promotes faster floc formation and greater bubble-particle interaction. This results in higher separation efficiency in the float tank, reduced carry-over to downstream filters, and lower demand for pH adjustment, especially when dealing with organic matter.
Because these coagulants do not introduce aluminium or iron residues, they also reduce the risk of fouling in desalination plant membranes and improve compatibility with biological polishing steps.
When and Where You Need It Most
DAF coagulants are used in a wide range of industries. In each case, their effectiveness in managing suspended solids determines not only water quality but also operational cost and compliance.
Meat processing: Removes suspended solids from animal fat, proteins and bone residue. Coagulation efficiency directly impacts final effluent clarity.
Dairy operations: Manages floatable solids and emulsified oils from the washing process. A well-matched coagulant can reduce COD loads before biological treatment.
Textile and dye production: Supports colour removal before secondary treatment. Tanafloc interacts effectively with organic dyes that resist traditional flocculants.
Food manufacturing: Handles starch, sugar and fine suspended matter that require strong charge neutralisation to prevent process downtime.
Paper mills: Clarifies high-density solids and recovers fibre in whitewater systems. Faster floc formation enables more reuse and reduced chemical dependency, particularly for suspended matter in the effluent.
In all these examples, the performance of your coagulant directly affects downstream processes such as sludge dewatering and filtration.
What Good Looks Like: Optimising Your DAF Chemistry
DAF performance is a balancing act. Coagulants are your counterweights. However, dosing a generic volume of chemical is not optimisation. True performance requires processes that ensure the quality of treated effluent, which may include applications in drinking water systems.
- Identifying particle charge via zeta potential testing
- Running jar tests to determine optimal dosage
- Checking compatibility with polymer flocculants
- Assessing floc size and buoyancy in real time
- Monitoring separation efficiency in the clarified water stream
These steps are essential if you want to minimise solids carryover and reduce energy consumption. Tanafloc provides in-field analysis, dosing support and process integration strategies, ensuring your system is tuned for real-world conditions.
Environmental and Operational Gains
Choosing a biodegradable coagulant is not just about improving your environmental credentials. It has practical benefits as well. Tanafloc’s natural polymer base:
- Reduces risks in chemical storage and handling
- Minimises the need for pH correction downstream
- Prevents aluminium or iron buildup in bio-reactors
- Lowers sludge disposal costs due to lower residual metals
When your DAF system, which relies on air flotation, is supported by the right coagulant, you are protecting every downstream unit from unnecessary wear, cost and compliance risks.
Ready to Upgrade Your DAF System?
Tanafloc Australia partners with industrial facilities, water treatment plants, and engineering firms to improve DAF performance in wastewater treatment through better chemistry. Whether you are installing a new dissolved air flotation system or upgrading an older one, we help you identify the correct formulation, dosage and integration method. Let your next DAF improvement begin with smarter chemical design, not more capital investment.
