Rotary Sieve (Trommel Screen)

The Robust and Gentle Solution for Screening Sticky, Moist, or Fragile Materials

The Rotary Sieve, also known as a Trommel Screen, is a highly reliable and low-maintenance screening machine. It consists of a rotating cylindrical drum, often fitted with screen panels, which gently tumbles and advances material. Its primary strengths lie in handling sticky, damp, or easily degradable granules, excelling at scalping (removing oversize), dedusting, and basic size separation where absolute precision is secondary to reliability and material compatibility.

Key Features

  • Rotating Drum Action

    Material is lifted by the rotating motion and gently cascades down, allowing smaller particles to pass through the screen apertures by gravity, minimizing granule breakage.

  • Self-Cleaning Design

    The tumbling action, combined with optional internal lifters or brushes, helps prevent screen blinding by sticky particles, a common issue with other screen types.

  • Variable Inclination & Speed

    The drum's angle and rotation speed are adjustable to control material retention time and screening efficiency.

  • Modular Screen Panels

    The cylindrical screen is typically made of replaceable, wear-resistant panels (polyurethane, rubber, or punched plate) for easy maintenance and aperture size changes.

  • Robust Construction

    Built with heavy-duty trunnion wheels, a strong frame, and a sealed drive system to withstand continuous operation in harsh, abrasive environments.

Advantages

  • Ideal for Challenging Materials

    Uniquely effective for screening sticky, moist (higher moisture content than vibrating screens can handle), clay-rich, or organic fertilizer materials without clogging.

  • Low Maintenance & High Uptime

    Simple mechanical principle with fewer vibration-related components results in minimal wear and extremely reliable, continuous operation.

  • Gentle on Product

    The rolling action causes significantly less granule attrition and degradation compared to vibrating screens, preserving granule integrity.

  • Excellent Scalping & Dedusting

    Perfect for removing large oversize particles (like lumps) or fine dust from a product stream in a single step.

  • Low Energy Consumption

    Typically requires less power than a vibrating screen of comparable capacity due to its simpler drive mechanism.

Applicable Raw Materials

  • Moist or Sticky Granules

    Freshly cooled granules with residual moisture, certain organic-based NPK blends.

  • Organic Fertilizers

    Compost, manure pellets, and other bio-fertilizers that are often damp and fibrous.

  • Reclaimed/Recycled Materials

    Wet or agglomerated fines being recycled back to the granulator.

  • Potassium Chloride (MOP)

    Can be effective for damp potash.

  • Soil Amendments

    Such as limestone or gypsum in pellet form.

Basic Structure & Components

Rotary Sieve (Trommel Screen)
Rotating Screen Drum

The core cylinder, constructed from a rigid frame covered with screen panels, slightly inclined.

Trunnion Wheels & Support Rollers

Heavy-duty wheels attached to the drum that rotate on support rails or rollers, bearing the drum’s weight.

Drive System

Consists of a motor, reducer, and chain/sprocket or gear drive to rotate the drum at a controlled speed.

Feed Hopper

Located at the elevated end of the drum, guiding material into the interior.

Oversize Discharge Chute

At the lower end of the drum, collects and discharges particles too large to pass through the screens.

Through-Size Collection Hopper

Located beneath the drum, collects the material that has passed through the screen apertures.

Dust Enclosure

Seals the drum to contain dust during operation.

Internal Lifters (Optional)

Angled bars inside the drum to enhance material lifting and tumbling for better screening efficiency.

Base Frame

A sturdy, stationary structure supporting all rotating components.

Technical Data

Type

Specification

Handling Capacity (t/h)

Motor Power (kW)

Turn Speed (r/min)

YS1860

Φ1.8×6m

15~20

15

16

YS2060

Φ2.0×6m

20~25

18.5

16

YS2280

Φ2.2×8m

30~40

30

15

YS2480

Φ2.4×8m

40~50

30

14.5

YS2680

Φ2.6×8m

50~60

37

13

Key Differentiators vs. Other Screeners

Excels at handling sticky, moist, or fragile materials without blinding, where a vibrating screen would struggle. It is a gentler, more robust, but less precise separator, better suited for scalping and dedusting rather than producing multiple tight product fractions. It typically has a larger footprint for the same capacity but offers simpler maintenance.

Provides continuous, automated operation with self-cleaning, eliminating the need for manual raking or cleaning required by static sieves. It offers significantly higher throughput and consistent results.

A Rotary Sieve provides full 360-degree screening action and can handle finer separations, while a grizzly is typically for very coarse scalping of large rocks ahead of a crusher.

It is the go-to solution for reliable, low-maintenance screening of difficult-to-handle, moist, or adhesive fertilizer materials, particularly in organic fertilizer production or in situations where equipment robustness and uptime are prioritized over ultra-fine sizing precision.