PRAESTOL 2640 is a high–molecular weight anionic polyacrylamide flocculant designed to enhance solid–liquid separation processes across various industrial and municipal applications. With its strong anionic charge density and long polymer chains, PRAESTOL 2640 effectively adsorbs onto fine suspended particles and forms polymer bridges between them, creating large, dense flocs that settle rapidly. Its chemical stability, high performance, and adaptability to harsh operating conditions make it a preferred choice for mining, mineral processing, alumina refining, industrial and municipal wastewater treatment, sludge dewatering, and energy-related processes.

1. Application in Mining and Mineral Processing

PRAESTOL 2640 is widely applied in mining and mineral processing operations, particularly in tailings thickening, clarification, and water recovery circuits. During crushing, grinding, flotation, and classification, mining operations produce large volumes of slurry containing fine mineral particles. These particles tend to remain suspended due to their small size and surface charge, which impedes natural sedimentation.

By adsorbing onto particle surfaces and forming polymer bridges, PRAESTOL 2640 promotes the aggregation of fine particles into large, dense flocs. This enhances settling rates and increases underflow solids concentration in thickeners and clarifiers. In operations involving copper, gold, iron ore, coal, phosphate, and bauxite, PRAESTOL 2640 improves thickener throughput, produces clearer overflow water, and enables efficient recycling of process water. Reduced freshwater consumption and minimized tailings storage contribute to operational efficiency and environmental sustainability.

2. Application in Alumina Refining and Red Mud Treatment

In alumina refineries operating under the Bayer process, PRAESTOL 2640 is extensively used for red mud thickening, settling, and washing circuits. Red mud is composed of extremely fine, highly alkaline particles, which are difficult to separate due to strong electrostatic repulsion and high slurry viscosity.

PRAESTOL 2640 performs effectively under high pH and elevated temperature conditions typical of alumina refining. When dosed into settlers and washers, it accelerates red mud settling, improves mud compaction, and enhances washing efficiency. Clearer overflow liquor results in improved recovery of sodium aluminate and reduced caustic soda losses. Efficient washing lowers residual alkalinity in disposed mud, supporting safer residue management and compliance with environmental regulations.

3. Application in Industrial Wastewater Treatment

PRAESTOL 2640 is widely applied in industrial wastewater treatment to remove suspended solids, colloidal particles, and fine inorganic matter. Industries such as metallurgy, cement, chemical processing, textiles, and power generation rely on effective flocculation to meet discharge standards or enable water reuse.

It is often used in combination with inorganic coagulants like aluminum sulfate, ferric chloride, or polyaluminum chloride. The coagulant destabilizes particle surface charges, while PRAESTOL 2640 promotes floc growth and strengthens floc structure through polymer bridging. This synergy improves sedimentation, dissolved air flotation (DAF), and filtration efficiency, resulting in lower turbidity, reduced sludge volume, and more stable wastewater treatment operations.

4. Application in Municipal Water Treatment

In municipal water treatment, PRAESTOL 2640 is used as a flocculation aid for raw water clarification, particularly for surface water sources with high turbidity caused by clay, silt, or fine suspended solids.

By forming large, shear-resistant flocs, PRAESTOL 2640 enhances sedimentation performance and reduces the load on downstream filtration systems such as sand filters or membrane units. This results in longer filter run times, reduced backwash frequency, and lower operational costs, while maintaining high-quality clarified water.

5. Application in Sludge Thickening and Dewatering

PRAESTOL 2640 is widely used as a sludge conditioning agent in industrial and municipal sludge treatment. Sludges often contain fine particles and colloids that retain water, making mechanical dewatering difficult.

When applied prior to gravity thickening or mechanical dewatering, PRAESTOL 2640 improves floc structure and promotes rapid water release. In belt filter presses, centrifuges, and filter presses, it increases cake solids content and improves filtrate clarity. Higher cake dryness reduces sludge volume, transportation, and disposal costs, resulting in more efficient and economical sludge management.

6. Application in Energy and Power Generation

In coal-fired power plants and other energy facilities, PRAESTOL 2640 is used for fly ash and bottom ash pond clarification. Ash particles are often fine and slow to settle, leading to large settling ponds and significant water loss.

PRAESTOL 2640 accelerates floc formation and settling of ash particles, producing clearer supernatant water that can be recycled for process or cooling purposes. This promotes water conservation and helps plants comply with strict environmental regulations.

7. Performance Advantages

PRAESTOL 2640 offers high flocculation efficiency at low dosage, rapid floc formation, and strong floc strength with excellent shear resistance. It is effective across a broad pH range and compatible with most coagulants. Its reliable performance, ease of preparation, and consistent dosing make it suitable for continuous, large-scale industrial and municipal operations.

8. Conclusion

Anionic polyacrylamide PRAESTOL® 2640 is a versatile and high-performance flocculant with proven applications in mining, alumina refining, industrial and municipal wastewater treatment, sludge dewatering, and energy-related processes. By enhancing settling, thickening, and clarification, it supports efficient water recovery, reduces operating costs, and ensures compliance with environmental regulations. Its robustness, adaptability, and consistent performance make PRAESTOL 2640 an essential component in modern solid–liquid separation and water management systems.