Application of PRAESTOL DW30 Anionic Polyacrylamide

PRAESTOL DW30 is a high–molecular weight anionic polyacrylamide (APAM) flocculant manufactured by Solenis (formerly Stockhausen). It is supplied primarily in powder form, designed for rapid dissolution and strong polymer bridging performance. With its anionic charge and long molecular chain structure, PRAESTOL DW30 is particularly effective for solid–liquid separation, clarification, sludge dewatering, and sedimentation of inorganic and mineral suspensions. It is widely applied in municipal and industrial water treatment, mining and mineral processing, papermaking, oilfield operations, and construction slurry treatment.

The working mechanism of PRAESTOL DW30 is based mainly on polymer bridging flocculation. After inorganic coagulants neutralize particle charges, the long-chain anionic polymer adsorbs onto multiple particles, linking them into large, dense flocs that settle rapidly or separate efficiently under mechanical force.

1. Municipal Water Treatment

One of the most important applications of PRAESTOL DW30 is in municipal water purification systems, where it is used as a coagulant aid together with aluminum sulfate, polyaluminum chloride (PAC), or ferric salts. Raw water typically contains fine clay, silt, algae, and colloidal particles that are difficult to remove by sedimentation alone.

After the inorganic coagulant destabilizes these particles, PRAESTOL DW30 promotes rapid floc growth and compact floc formation, resulting in:

• Faster sedimentation

• Lower turbidity in clarified water

• Improved filtration efficiency

• Reduced filter backwash frequency

• Lower overall chemical consumption

It is also used in drinking water sludge thickening and dewatering, improving the handling and disposal efficiency of mineral-rich treatment residuals.

2. Municipal and Industrial Wastewater Treatment

PRAESTOL DW30 plays a vital role in municipal and industrial wastewater treatment, especially in systems dominated by inorganic suspended solids. Typical application fields include:

• Sand and gravel washing wastewater

• Stone and aggregate processing effluents

• Ceramic and glass factory wastewater

• Power plant flue gas desulfurization (FGD) wastewater

• Steel plant and metallurgical wastewater

• Construction slurry and tunneling wastewater

In these systems, PRAESTOL DW30 effectively aggregates fine sand, ash, clay, metal hydroxides, and other mineral particles, producing rapid settling and clear supernatant water. Compared with cationic polymers, PRAESTOL DW30 shows superior performance in low-organic, high-mineral-content wastewater.

In dissolved air flotation (DAF) units, PRAESTOL DW30 is often applied together with PAC or ferric salts to strengthen microflocs and improve flotation separation efficiency.

3. Sludge Thickening and Mechanical Dewatering

Another major application of PRAESTOL DW30 is sludge conditioning and mechanical dewatering, particularly for inorganic and chemically precipitated sludges. These include:

• Primary sedimentation sludge

• Lime sludge

• Chemical precipitation sludge

• Metal hydroxide sludge

• Mixed municipal–industrial sludge

PRAESTOL DW30 is used in various sludge handling systems, including:

• Gravity thickeners

• Belt filter presses

• Decanter centrifuges

• Plate-and-frame filter presses

Its high molecular weight allows it to form strong bridges between sludge particles, producing large, permeable flocs that release water rapidly under pressure. This leads to:

• Higher sludge cake dryness

• Lower filtrate turbidity

• Reduced polymer consumption

• Lower energy usage in dewatering equipment

• Reduced sludge transportation and disposal costs

Because it is an anionic polymer, it performs best when sludge has been pretreated with metal salts, allowing the polymer to focus on bridging rather than charge neutralization.

4. Mining and Mineral Processing Industry

PRAESTOL DW30 is extensively used in mining and mineral beneficiation operations, where efficient solid–liquid separation is essential for both productivity and environmental protection. It is widely applied in:

• Coal processing

• Iron ore beneficiation

• Copper and gold extraction

• Bauxite and phosphate processing

• Silica sand washing

Its main functions in mining include:

• Tailings thickening

• Clarification of circulating process water

• Concentrate dewatering

• Backfill material preparation

Fine mineral particles are naturally slow to settle due to their small size and stable surface charges. PRAESTOL DW30 rapidly flocculates these particles into large aggregates, enabling fast sedimentation and production of clear overflow water. This allows:

• Efficient recycling of process water

• Reduced tailings pond area

• Improved water balance and cost control

• Enhanced environmental compliance

5. Papermaking and Pulp Industry

In the papermaking industry, PRAESTOL DW30 is mainly used as a retention and drainage aid, particularly in paper grades that contain high levels of mineral fillers such as calcium carbonate and kaolin.

Its key benefits include:

• Increased retention of fibers and fillers

• Faster drainage on the wire section

• Reduced white water solids

• Improved paper formation and uniformity

• Higher machine running speed and productivity

PRAESTOL DW30 is widely applied in the production of packaging paper, corrugated paper, cultural paper, and industrial specialty papers, while also reducing pollutant load in papermaking wastewater.

6. Oilfield and Energy-Related Applications

In the oil and gas industry, PRAESTOL DW30 is used for:

• Drilling wastewater clarification

• Separation of clay and drill cuttings

• Produced water solid removal

• Refinery wastewater primary treatment

It effectively aggregates inorganic solids and fine suspended particles, improving sedimentation and supporting water recycling, reinjection, and discharge compliance.

7. Construction, Tunneling, and Infrastructure Projects

Large-scale construction projects generate high volumes of slurry wastewater containing bentonite, cement, clay, and fine sand. PRAESTOL DW30 is widely applied in:

• Shield tunneling slurry separation

• Piling and foundation wastewater treatment

• Metro and underground engineering projects

It rapidly clarifies muddy water, allowing for water reuse, reduced sediment volume, and improved project efficiency.

8. Key Advantages of PRAESTOL DW30

PRAESTOL DW30 offers several significant commercial and technical advantages:

• Very high molecular weight for strong flocculation

• Excellent performance in inorganic suspensions

• Fast settling and clear supernatant water

• Low dosage requirement

• Wide pH adaptability

• Strong compatibility with PAC, alum, and ferric salts

• Stable and consistent performance under variable water conditions

Conclusion

PRAESTOL® DW30 Anionic Polyacrylamide is a highly efficient flocculant designed for inorganic solid–liquid separation, clarification, and sludge dewatering. Its main applications include municipal and industrial water treatment, sludge thickening and dewatering, mining and mineral processing, papermaking, oilfield wastewater treatment, and construction slurry separation. Through strong polymer bridging, rapid floc formation, and excellent settling performance, PRAESTOL DW30 significantly improves treatment efficiency, reduces operating costs, and enhances environmental compliance. Its wide adaptability, reliable performance, and cost-effectiveness make it one of the most widely used anionic flocculants in modern industrial and environmental engineering systems.