Crushed and Dried Bentonite

Our crushed and dried bentonite is a carefully processed intermediate product that combines the natural binding power of montmorillonite clay with the convenience of standardized particle sizing and controlled moisture content. Sourced from the premium Askanian deposit in Georgia, this material undergoes crushing and drying to produce a free-flowing, easy-to-handle product that maintains its exceptional swelling and binding properties.

Processing for Industrial Performance: Unlike raw bentonite clay, our crushed and dried product undergoes controlled processing to optimize handling and performance:

• Crushing: Reduces material to uniform 0-5mm particle size for consistent mixing and dosing
• Drying: Reduces moisture to ≤12% for stable weight, easier transport, and extended shelf life
• Screening: Removes oversized particles to ensure uniform distribution in final applications
• Quality Control: Batch testing guarantees consistent montmorillonite content and swelling properties

The Montmorillonite Advantage: The secret to bentonite’s industrial value lies in its montmorillonite content (>70% in our premium grade). This unique clay mineral features a layered structure with enormous surface area and exceptional cation exchange capacity (70-90 meq/100g). When hydrated, montmorillonite platelets swell dramatically, creating powerful binding forces through ionic attraction and mechanical interlocking.

Key Applications:

Iron Ore Pelletizing (Primary Application)

Role in Pellet Production:

• Acts as primary binder for iron ore concentrate in pelletizing drums or discs
• Creates strong “green” (unfired) pellets that survive handling and transport to induration furnaces
• Maintains pellet integrity through drying and high-temperature firing (>1200°C)
• Produces durable, high-quality pellets for blast furnace feed

How It Works: Crushed and dried bentonite (typically 0.5-1.5% by weight) is blended with iron ore concentrate and water in rotating pelletizing equipment. As the mixture tumbles, bentonite particles hydrate and swell, forming a binding matrix that glues iron ore particles together into spherical pellets. The swollen clay platelets create both physical bridges and ionic bonds between ore particles, resulting in pellets with sufficient green strength (>1 kg/pellet compression) to withstand subsequent processing.

Critical Performance Parameters:

• Swelling Index: >20 ml/2g indicates excellent binding potential
• Montmorillonite Content: >70% ensures maximum swelling and binding
• Colloidal Fraction: >90% provides fine particles for complete ore coating
• Moisture Control: <12% allows accurate dosing and predictable performance
• Particle Size: 0-5mm ensures rapid, uniform dispersion in ore concentrate

Benefits for Pellet Plants:

• Increases pelletizing drum/disc productivity by 10-20%
• Improves green pellet compressive strength to >1 kg/pellet
• Reduces fines and return material in the process
• Enhances fired pellet strength to >250 kg/pellet
• Improves iron reducibility in blast furnaces
• Reduces fuel consumption during induration

Foundry Applications

Role in Metal Casting:

• Primary binder for green sand molding systems
• Creates molds and cores that hold shape during metal pouring
• Provides “green strength” (unfired mold integrity) and thermal stability
• Enables reuse of molding sand (up to 95% recycling rate)

How It Works in Foundries: Crushed and dried bentonite (8-12% by weight) is mixed with silica sand and water to create green sand molding mixtures. The hydrated bentonite particles coat sand grains with a thin clay film. When compacted, this clay coating bonds sand grains together, creating a mold strong enough to withstand the pressure and heat of molten metal yet porous enough to allow gas escape. After casting cools, the sand-clay mixture can be reconditioned and reused.

Molding Sand Types:

• Sodium Bentonite Systems: For steel casting (high-temperature applications >1400°C)
• Calcium Bentonite Systems: For iron casting (moderate temperatures ~1200°C)
• Mixed Systems: Balanced properties for diverse casting needs

Critical Foundry Properties:

• Green Compressive Strength: >7 psi (steel), >5 psi (iron)
• Green Tensile Strength: >25 g/cm²
• Permeability: 80-120 units (allows gas escape during pouring)
• Plasticity: High for easy ramming and compaction
• Thermal Stability: Maintains binding to 1500°C

Benefits for Foundries:

• Improves dimensional accuracy of castings
• Reduces surface defects (veining, penetration, scabs, rat tails)
• Enables high sand reuse rates (cost and environmental benefits)
• More economical than synthetic binders
• Non-toxic (no hazardous fumes during metal pouring)

Civil Engineering & Construction

Typical Applications:

• Waterproofing for foundation excavations and basements
• Bentonite slurry for deep foundation drilling and diaphragm walls
• Sealing liners for ponds, lagoons, and landfills
• Well sealing and groundwater protection
• Soil stabilization and erosion control

How It Works: When mixed with water, crushed and dried bentonite swells to 12-15 times its dry volume, forming a gel-like barrier with extremely low hydraulic conductivity (<10⁻⁹ m/s). This swelling property makes bentonite an effective, self-healing sealant—if cracks develop, surrounding bentonite migrates into the void and re-swells to maintain the seal.

Civil Engineering Benefits:

• Creates reliable, long-lasting waterproof barriers
• Self-healing capability (cracks automatically seal)
• Natural, environmentally safe material
• Cost-effective compared to synthetic membranes
• Easy installation and application

Additional Industrial Uses

Drilling Fluids (Oil & Gas):

• Lubricates and cools drill bit
• Carries drill cuttings to surface
• Stabilizes borehole walls
• Forms low-permeability filter cake

Ceramics Industry:

• Plasticizer for ceramic bodies
• Improves workability and green strength
• Reduces cracking in unfired ware

Chemical Processing:

• Catalyst carrier/support
• Absorbent for oil and grease purification
• Thickener for paints, coatings, and adhesives