MAGNAFLOC® 338 is a high–molecular-weight anionic polyacrylamide flocculant widely used in solid–liquid separation processes across mining, mineral processing, metallurgy, alumina refining, and industrial water treatment. Due to its strong anionic charge density and excellent bridging capability, MAGNAFLOC® 338 is particularly effective for flocculating fine, negatively charged mineral particles and metal oxide suspensions under alkaline conditions.

1. General Characteristics and Flocculation Mechanism

MAGNAFLOC® 338 operates primarily through a polymer bridging mechanism, where long polymer chains adsorb onto multiple particles simultaneously, forming large, dense flocs. The anionic functional groups along the polymer backbone enhance adsorption onto positively charged sites on mineral surfaces, especially in high-pH environments.

Compared with lower-molecular-weight anionic polyacrylamides, MAGNAFLOC® 338 provides:

• Faster settling rates

• Improved overflow clarity

• Stronger, shear-resistant flocs

• Enhanced underflow solids concentration

These properties make MAGNAFLOC® 338 suitable for high-throughput thickeners and clarifiers.

2. Application in Mining and Mineral Processing

2.1 Tailings Thickening and Clarification

One of the primary applications of MAGNAFLOC® 338 is in tailings thickening for mining operations such as:

• Copper

• Gold

• Iron ore

• Phosphate

• Coal washing

In tailings circuits, fine mineral particles remain suspended after grinding and flotation. MAGNAFLOC® 338 accelerates particle aggregation, allowing rapid sedimentation in:

• High-rate thickeners

• High-density thickeners

• Deep-cone paste thickeners

The use of MAGNAFLOC® 338 results in:

• Higher underflow density

• Reduced water content in tailings

• Improved water recovery for reuse

• Lower operating costs in tailings disposal

2.2 Clarification of Process Water

MAGNAFLOC® 338 is extensively used to clarify recycled process water in mining plants. By removing suspended solids, it:

• Reduces turbidity

• Prevents scaling and abrasion in pumps and pipelines

• Improves flotation and leaching efficiency

Clearer recycled water directly enhances overall plant stability and metallurgical performance.

3. Application in Alumina and Bauxite Processing

In alumina refineries, MAGNAFLOC® 338 plays an important role in red mud settling and washing circuits. During the Bayer process, bauxite digestion generates large volumes of alkaline slurry containing fine red mud particles.

MAGNAFLOC® 338 is applied in:

• Primary settlers

• Mud washers

• Counter-current decantation (CCD) circuits

Its benefits include:

• Faster red mud settling rates

• Improved liquor clarity

• Enhanced recovery of caustic soda

• Reduced mud carryover into pregnant liquor

Because MAGNAFLOC® 338 performs well under extremely high pH and temperature, it is well suited for alumina operations requiring stable long-term flocculation performance.

4. Application in Industrial Water and Wastewater Treatment

4.1 Primary and Secondary Clarification

MAGNAFLOC® 338 is used as a primary flocculant or co-flocculant in industrial wastewater treatment plants handling:

• Mineral slurry wastewater

• Metallurgical effluents

• Chemical process water

• Power plant ash pond water

When combined with inorganic coagulants such as alum or ferric salts, MAGNAFLOC® 338 improves:

• Floc size

• Settling velocity

• Sludge dewatering characteristics

4.2 Sludge Thickening and Dewatering

In sludge treatment systems, MAGNAFLOC® 338 enhances the performance of:

• Gravity thickeners

• Belt filter presses

• Vacuum filters

• Centrifuges

The polymer forms strong, drainable flocs, resulting in:

• Higher cake solids

• Lower polymer consumption

• Reduced sludge handling costs

5. Application in Coal Preparation and Washing Plants

MAGNAFLOC® 338 is widely applied in coal washing plants for the clarification of:

• Fine coal tailings

• Black water circuits

Its strong anionic nature allows effective flocculation of coal fines and clay particles, improving:

• Thickener throughput

• Overflow clarity

• Water reuse efficiency

The use of MAGNAFLOC® 338 contributes to environmental compliance by minimizing suspended solids discharge.

6. Application in Metallurgical and Chemical Industries

In metallurgical processes, MAGNAFLOC® 338 assists in the clarification of:

• Acid leach residues

• Hydrometallurgical process solutions

• Neutralization sludges

In chemical plants, it is used to remove fine inorganic solids from:

• Process effluents

• Cooling water blowdown

• Reactor wash waters

Its chemical stability allows consistent performance even in high-salinity or variable-composition systems.

7. Dosage, Preparation, and Handling

MAGNAFLOC® 338 is typically supplied as a dry granular powder. Proper preparation is critical for optimal performance:

• Make-down concentration: 0.1–0.5%

• Hydration time: 45–60 minutes

• Gentle agitation to avoid polymer degradation

Dosage varies depending on solids concentration and particle characteristics, typically ranging from 5 to 100 g/t of dry solids.

8. Summary of Key Benefits

In summary, MAGNAFLOC® 338 is a versatile and high-performance anionic polyacrylamide flocculant offering:

• Rapid settling and superior clarification

• High underflow density

• Strong floc structure

• Excellent performance in alkaline systems

• Reduced water consumption and operating costs

These advantages make MAGNAFLOC® 338 a preferred flocculant in mining, alumina refining, coal processing, and industrial water treatment applications.