Application of Polyamine FLOQUAT™ FL 2250, FL 2350, and FL 2550

1. Introduction to FLOQUAT™ Polyamine Series

FLOQUAT™ FL 2250, FL 2350, and FL 2550 are cationic polyamine coagulants developed by SNF for use in water and wastewater treatment, industrial effluent clarification, and solid–liquid separation processes. These products belong to the polyamine polymer family, which is characterized by high cationic charge density, low to medium molecular weight, and excellent charge neutralization capability.

Unlike inorganic coagulants such as aluminum sulfate or ferric chloride, polyamines work primarily through electrostatic charge neutralization, destabilizing negatively charged colloids and fine suspended solids. This makes FLOQUAT™ polyamines highly effective over a wide pH range and particularly suitable for applications requiring rapid clarification, reduced sludge volume, and improved downstream dewatering.

Although FLOQUAT™ FL 2250, FL 2350, and FL 2550 share a common chemistry, they differ slightly in charge density, viscosity, and performance balance, allowing users to select the most appropriate grade for specific treatment conditions.

2. Municipal Water Treatment Applications

2.1 Raw Water Clarification

FLOQUAT™ FL 2250, FL 2350, and FL 2550 are widely used in municipal drinking water treatment plants as primary coagulants or coagulant aids. They are effective in treating surface water containing clay, silt, organic matter, and colloidal particles.

• FL 2250 is often selected for low to moderate turbidity water, where gentle but effective charge neutralization is required.

• FL 2350 offers a balanced performance for seasonal turbidity variations, especially during rainy periods.

• FL 2550, with relatively higher charge density, performs well in high turbidity or high organic load waters.

These products improve floc formation, accelerate sedimentation, and reduce residual turbidity, leading to clearer filtrate water and extended filter run times.

2.2 Reduction of Inorganic Coagulant Dosage

When used in combination with alum or ferric salts, FLOQUAT™ polyamines significantly reduce the required dosage of inorganic coagulants. This leads to:

• Lower sludge production

• Reduced corrosion risk

• Improved treated water quality

• Lower operational costs

3. Municipal Wastewater Treatment Applications

3.1 Primary Clarification

In municipal wastewater treatment plants, FLOQUAT™ FL 2250, FL 2350, and FL 2550 are applied in primary clarifiers to enhance the removal of suspended solids, fats, oils, and grease (FOG).

• Polyamines rapidly destabilize fine particles and emulsified oils.

• They improve settling velocity and clarify overflow water.

• They help reduce organic loading to secondary biological treatment.

FL 2350 and FL 2550 are commonly preferred in high-strength municipal influent, while FL 2250 is used where wastewater characteristics are relatively stable.

3.2 Sludge Thickening and Conditioning

These polyamines are also used as sludge conditioning agents before gravity thickening or mechanical dewatering. Their high cationic charge neutralizes negatively charged sludge particles, improving:

• Sludge compaction

• Free water release

• Thickener performance

Polyamines are often used ahead of cationic polyacrylamide flocculants to reduce overall polymer consumption.

4. Industrial Wastewater Treatment Applications

4.1 Paper and Pulp Industry Effluent

FLOQUAT™ FL 2250, FL 2350, and FL 2550 are highly effective in treating paper mill wastewater, which contains high levels of fibers, fillers, inks, and dissolved organic substances.

Key benefits include:

• Efficient removal of suspended solids and fines

• Improved fiber recovery

• Reduced COD and turbidity

• Enhanced performance of dissolved air flotation (DAF) systems

FL 2550 is particularly effective for coated paper and recycled fiber effluents, where contaminant loads are high.

4.2 Textile and Dyeing Wastewater

Textile wastewater often contains negatively charged dyes and surfactants, making polyamines an ideal treatment choice. FLOQUAT™ polyamines:

• Neutralize dye molecules

• Promote color removal

• Improve sedimentation and flotation efficiency

FL 2350 and FL 2550 are widely used for high-color, high-COD textile effluents, while FL 2250 is suitable for lighter dye loads.

4.3 Food and Beverage Industry Wastewater

In food processing plants (breweries, dairies, meat processing), FLOQUAT™ polyamines are used to remove:

• Proteins

• Fats and oils

• Suspended organic solids

These products help stabilize treatment systems, reduce organic load on biological processes, and improve sludge handling.

5. Oil, Gas, and Refinery Wastewater

Polyamine FLOQUAT™ grades are effective in treating oily wastewater, including refinery effluent and oilfield produced water.

Applications include:

• Oil–water separation

• Emulsion breaking

• Clarification prior to flotation or filtration

FL 2550, with stronger charge neutralization, is especially effective for stable oil emulsions, while FL 2250 and FL 2350 are used in less severe conditions.

6. Pretreatment for Advanced Flocculation Systems

FLOQUAT™ FL 2250, FL 2350, and FL 2550 are frequently applied as pretreatment coagulants before high-molecular-weight flocculants such as cationic or anionic polyacrylamide.

This two-step approach provides:

• Improved floc structure

• Lower polymer consumption

• Faster settling and dewatering

• More stable process control

7. Operational Advantages of FLOQUAT™ Polyamines

Across applications, these products offer several practical benefits:

• Effective over a wide pH range

• Fast reaction and short mixing time

• Low dosage compared to inorganic coagulants

• Reduced sludge volume

• Improved downstream dewatering efficiency

FL 2250 provides cost-effective clarification, FL 2350 offers balanced versatility, and FL 2550 delivers maximum performance under demanding conditions.