Pigment Blender Product

Overview

A pigment blender is an industrial batch mixer designed for homogenizing dry powders: pigments, toners, cosmetic colorants, and additives. Unlike liquid mixers, pigment blenders use ribbon or plough agitators to tumble and fold powders, ensuring uniform color and composition.

The mixer is enclosed and fitted with dust extraction equipment (cyclone + bag filter) to contain airborne pigment and protect plant air quality. Jackets with cool water help control temperature rise from friction and compaction.

How it works

Dry ingredients (pigments, fillers, additives) are manually loaded through the Access Loading Door. The operator closes the door and sets the blend time on the Speed and Timer Controls timer, then presses the start button.

The Variable-Speed Motor and Gearbox energizes, rotating the Drive Shaft at 20–60 rpm (set by the Speed Potentiometer). The Ribbon Agitator Blade helical blades radially sweep through the powder, lifting it upward and across the vessel. The Plough Blade optionally shears compacted zones toward the ribbons. Powder tumbles, rubs together, and blends uniformly.

As blending proceeds, powder dust is drawn into the Dust Extraction System hood by the Extraction Blower. The Cyclone Separator removes 99.5% of large particles; a Cartridge Filter captures ultrafine dust. Filtered air exhausts to atmosphere or ducting.

The Cooling Jacket and Circulation removes frictional heat via Standalone Chiller coolant, maintaining vessel temperature below 35°C (critical for thermally sensitive pigments like organic reds).

When the Digital Timer expires, the Variable-Speed Motor and Gearbox stops automatically. The operator opens the Bottom Discharge System butterfly valve, and powder gravity-drains into a collection bag via the Discharge Chute. A {{pigment-blender-bag-holder}} clamp holds the bag open.

Key subsystems

Vessel design: The Vessel Shell is a tall cylinder (height-to-diameter ratio typically 1:1 to 2:1) ensuring maximum blade immersion. The Double-Wall Jacket is integrated, allowing coolant circulation around the full perimeter. An internal Internal Baffle (vertical divider) reduces bypassing and dead zones common in simple cylindrical vessels.

Agitators: Ribbon blenders use Ribbon Agitator Blade helical blades (typically two blades rotating in opposite helical directions) sweeping the full diameter. Plough blenders add a Plough Blade (angled pusher blade) that drives powder against the ribbons for additional shear. Ribbon-only designs suit free-flowing powders; ribbon + plough suits cohesive or compacted pigments.

Dust control: The Dust Extraction System hood fits over the Access Loading Door and vessel top, creating a sealed collection system. The Extraction Blower creates negative pressure (100–300 Pa below atmospheric), pulling dust up into the hood. The Cyclone Separator is the primary separator; the Cartridge Filter is a secondary fine-dust capture. Collected dust falls into a Dust Collection Drum, which is manually exchanged or dumped.

Discharge: The Bottom Discharge System butterfly valve is pneumatically or electrically actuated, opening to gravity-drain powder. A Solenoid or Electric Actuator on the Speed and Timer Controls controls opening/closing timing.

Cooling system: The Standalone Chiller is a standalone unit (2–10 kW) circulating coolant at 15–25°C via Circulation Pump through the Cooling Jacket and Circulation. A Jacket Temperature Gauge on the jacket outlet indicates temperature. For sensitive pigments (e.g., organic reds, phthalocyanine blues), cooling is essential to prevent discoloration from heat.

Materials and construction

Vessel: Stainless steel 304 or 316L, with internal surface electropolished to 20 µin Ra (high polish) to minimize powder adhesion and ease cleaning. Jacketed walls are typically 5–8 mm thick steel with 10–15 mm spacing for efficient heat transfer.

Blades: Stainless steel or hardened carbon steel (55–60 HRC). Some designs include hardened-steel or ceramic coatings on blade edges to resist abrasive pigment powder.

Motor and drive: Three-phase induction motor (IE3 efficiency standard) coupled through a helical gearbox. The Variable-Frequency Drive or soft-starter provides gentle acceleration to avoid powder "packing" (sudden compaction that stalls the motor).

Sealing: All dynamic seals are PTFE or Viton for broad chemical compatibility. The shaft Oil Seal at the vessel top is a mechanical lip-seal design rated for powder-laden air environment.

Operating procedure

1. Load dried pigment and additives via the Access Loading Door.
2. Close and lock the access door.
3. Ensure Cooling Jacket and Circulation chiller is running at setpoint (15–25°C).
4. Set blend time on Speed and Timer Controls timer (typical 15–25 minutes for thorough homogenizing).
5. Set speed on Speed Potentiometer (typically 40–60% for cohesive pigments, 80–100% for free-flowing).
6. Press START.
7. Verify LED Status Indicator green indicator is lit and Extraction Blower is drawing dust.
8. Monitor Jacket Temperature Gauge; temperature should rise gradually, not exceed 35°C.
9. When timer expires, motor stops automatically.
10. Wait 30 seconds for residual powder to settle.
11. Open Bottom Discharge System butterfly valve manually or via control panel solenoid.
12. Collect powder in bag via Discharge Chute; seal bag.
13. Close Bottom Discharge System.
14. Clean vessel interior: run empty mixer for 1 minute, then spray interior with compressed air.
15. Empty Dust Collection Drum cyclone collection.

Performance metrics

Blend uniformity: Ribbon blenders achieve color uniformity (ΔE < 0.5) in 15–25 minutes for 100 liter batches. Smaller batches (10–20 liter) blend faster; larger batches (300+ liter) require 30–45 minutes.

Torque and power: A 1.5 kW motor driving a 100 liter batch typically draws 70–80% rated power at steady state. Startup current is limited by the Variable-Frequency Drive soft-starter to prevent electrical inrush.

Temperature rise: Frictional heating in a typical batch is 2–5°C per 10 minutes of blending. The Cooling Jacket and Circulation removes ~500 W of heat continuously, limiting temperature rise to 5–10°C total.

Dust containment: With Cyclone Separator + Cartridge Filter running, emission rate is typically <10 mg/m³, well below OSHA limits (15 mg/m³ TWA for total dust).

Variants and options

Single ribbon vs. dual ribbon: Single-ribbon blenders are compact and cheaper; dual-ribbon designs (counter-rotating helices) give superior mixing and are standard for production facilities.

Plough attachment: Plough blade is optional, adding cost but improving blend for sticky/cohesive pigments or pastes.

Discharge options: Simple gravity discharge via butterfly valve; pneumatic or electric actuation; auger or screw pump discharge for higher viscosity pastes.

Vacuum-rated vessels: Reactors for degassing moisture from pigments operate under partial vacuum (0.1–0.3 bar) for extended drying times (1–2 hours).

Tilting design: Small 10–50 liter mixers on motorized tilt frames allow pour-out without bottom discharge valve.

Cleaning and maintenance

Powder contamination is the chief concern. Removable blade assemblies allow thorough internal cleaning. Most operators run a "seasoning" batch of inert powder (talc) followed by air spray-out between batches of different pigments.

Blade wear is gradual; typical life is 1000–2000 hours before replacement. Cartridge Filter cartridges clog after 50–100 batches and require replacement.

The Cooling Jacket and Circulation system should be flushed monthly to prevent scaling. High-mineral chiller fluid can precipitate in small jacket channels.