Application of Polydadmac (BPW76440, BPW76450, BPW76453, BPW76455)

1. Introduction to BPW Polydadmac Series

BPW76440, BPW76450, BPW76453, and BPW76455 are liquid cationic polydiallyldimethylammonium chloride (PolyDADMAC) polymers widely used in municipal and industrial water and wastewater treatment. Polydadmac is a high-charge-density cationic polymer, functioning primarily through charge neutralization. It destabilizes negatively charged colloidal particles, natural organic matter (NOM), algae, fine suspended solids, and emulsified contaminants.

Unlike long-chain polyacrylamide flocculants that mainly rely on bridging mechanisms, the BPW polydadmac series is particularly effective at destabilizing small colloids and fine particles, making them suitable for both drinking water clarification and industrial effluent treatment. The four grades differ in charge density, molecular weight, and viscosity, allowing water treatment operators to select the most suitable polymer for specific water quality conditions.

2. Municipal Drinking Water Treatment Applications

2.1 Raw Water Clarification
The BPW polydadmac products are commonly applied as primary coagulants in municipal water treatment plants. Surface water, river water, and reservoirs often contain clay, silt, algae, and NOM, all negatively charged and resistant to settling.

When BPW polydadmac is dosed in a rapid-mix or inline-mix zone:

• Negative charges are neutralized rapidly, producing microflocs.

• Flocs grow and settle more efficiently in sedimentation basins.

• Turbidity is reduced, resulting in clearer water for downstream filtration.

2.2 Coagulant Aid for Metal Salts
BPW76440, BPW76450, BPW76453, and BPW76455 are frequently used as coagulant aids alongside aluminum sulfate, ferric chloride, or polyaluminum chloride. Their use:

• Improves floc formation and settling velocity.

• Reduces the required dosage of inorganic coagulants.

• Lowers sludge volume and residual metal content in treated water.

• Enhances filter run times and minimizes filter maintenance.

2.3 Color and Organic Matter Removal

• Effective for removing humic and fulvic acids, which contribute to color and act as disinfection by-product (DBP) precursors.

• Reduces the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) during chlorination.

2.4 Algae and Seasonal Turbidity Control

• High-charge variants, such as BPW76453 and BPW76455, are effective in destabilizing algae and fine colloids during seasonal blooms.

• Reduces filter headloss and improves overall plant stability.

3. Municipal Wastewater Treatment Applications

3.1 Primary Clarification Enhancement
BPW polydadmac products enhance primary clarifier performance by accelerating the settling of suspended solids, fats, oils, and grease (FOG). The polymers neutralize the colloidal charges of fine particles, forming denser, faster-settling flocs.

3.2 Sludge Conditioning and Dewatering

• Applied to sludge before gravity thickening, centrifugation, or belt filter pressing.

• Neutralizes particle charges, promoting aggregation and improving free water release.

• When used in combination with high-molecular-weight polyacrylamide flocculants, they improve cake dryness and reduce overall polymer consumption.

3.3 Secondary Clarification Support

• Supports the removal of fine suspended solids that escape primary treatment.

• Helps stabilize downstream biological processes by reducing solids load.

4. Industrial Wastewater Applications

4.1 Food and Beverage Industry

• Treats wastewater containing proteins, fats, oils, and suspended solids.

• Destabilizes emulsified oils and organic matter, facilitating separation and reducing COD prior to biological treatment.

4.2 Pulp and Paper Industry

• Clarifies effluent containing fiber fines, fillers, inks, and dissolved organics.

• Enhances dissolved air flotation (DAF) performance, reduces residual turbidity, and improves water recovery.

4.3 Textile and Dyeing Industry

• Neutralizes negatively charged dyes and surfactants.

• Promotes sedimentation of colloidal solids and removal of color from effluent streams.

4.4 Oil, Gas, and Petrochemical Effluent

• Breaks emulsified oils and dispersed solids.

• Enhances the performance of API separators, flotation units, and secondary clarifiers.

5. Operational Advantages

• Rapid coagulation due to high cationic charge density.

• Versatile performance across a wide pH and temperature range.

• Reduced sludge production compared to inorganic coagulants alone.

• Improved downstream operations: enhances filtration, dewatering, and sludge handling.

• Easy handling and dosing as a stable liquid concentrate compatible with standard injection systems.

• Environmental compliance: reduces the use of metal salts and associated residuals.

6. Typical Dosing and Integration

• Typical dosage: 0.5–10 mg/L, depending on raw water or wastewater characteristics.

• Can be applied alone or with inorganic coagulants.

• Injection points: rapid-mix basin, inline injection, or pre-clarifier feed.

• Often paired with anionic or nonionic flocculants for enhanced floc formation and improved sludge dewatering.

Grade Selection Guidelines:

• BPW76440 – Medium-charge, suitable for moderate turbidity and routine municipal applications.

• BPW76450 – Medium-to-high charge, effective for moderate to high turbidity and organics.

• BPW76453 – High-charge, for challenging waters with high turbidity, color, or algae.

• BPW76455 – Very high-charge, for extreme conditions such as seasonal algal blooms or high-NOM waters.