Sugar grinding is a critical process for the bakery, confectionery, and beverage industries, requiring precise particle sizes ranging from coarse "Castor Sugar" to ultra-fine "Icing Sugar." However, processing sugar presents two major challenges:
- Hygroscopic Nature: Sugar readily absorbs moisture from the air, leading to lumping, caking, and potential blockage of the grinding system.
- Explosive Dust: Fine sugar dust is highly combustible (St1 Hazard Class), posing significant safety risks.
RIECO Industries provides a specialized Sugar Grinding System designed to overcome these challenges. By integrating Controlled Atmosphere Grinding (Dehumidification) with Explosion Protection technologies, our systems ensure continuous, safe, and dust-free operation while delivering the precise fineness required for applications like chocolate, icing, and instant mixes.
Design and Working Principle
The system is designed to operate in a "Cool and Dry" environment to prevent the sugar from melting or caramelizing.
- Feeding: S30 sugar is fed into the mill via a screw feeder mounted on the mill hopper — or via an externally controlled feed that feeds directly into the mill hopper. The feed arrangement provides a steady, metered input to the pulveriser.
- Grinding: The micro pulveriser reduces feed to the target fineness (95% < 250 micron). The grinding chamber is arranged vertically so material discharges downwards by gravity.
- Gravity discharge & buffering: Ground material falls into a discharge hopper located directly below the pulveriser. This hopper acts as a buffer to ensure even downstream discharge.
- Sealed discharge: A Rotary Air Lock (RAL) mounted below the discharge hopper provides an air -sealed, controlled discharge into collection drums/bins.
- Dust control / breathing: Air and entrained dust from the mill are drawn (or vented) through stainless ducting to the Vent Bag Filter. The C-Fan provides the required air movement for mill “breathing” and ensures dust is carried to the filter.
- Filtration & collection: The bag filter captures fine dust; filtered air is released (or recirculated as required). Filtered product in the filter hopper discharges into the RAL / collection drum as part of the product recovery path.
- Control & safety: The basic control scheme interlocks feeder, mill, fan and RAL to prevent overfeeding and to ensure the filter/fan is running during mill operation.
For Universal Mill Case
Step 1: Feeding Section
Sugar S30 is introduced into the Feed Hopper located at the upper level of the system.
A Rotary Air Lock (RAL) mounted directly below the hopper meters the sugar into the mill at a controlled rate.
This arrangement ensures smooth and choke-free feeding into the BT-450 mill.
Step 2: Grinding Section – Universal Mill BT-450
The metered sugar enters the BT-450 Universal Mill, where size reduction occurs through impact and milling action.
The mill is centrally positioned so that ground product falls vertically downward.
Step 3: Gravity Discharge & Product Buffering
Ground sugar drops by gravity into the Discharge Hopper placed directly below the BT-450.
The hopper stabilizes product flow and prevents surging during downstream discharge.
Step 4: Sealed Discharge to Collection
A second Rotary Air Lock (RAL) is located under the discharge hopper.
This RAL provides air-sealed discharge into a small collection drum or product handling bin.
This ensures clean, dust-free collection of finished sugar powder.
Step 5: Dust Collection & Mill Breathing
A Vent Filter is connected to the mill through ducting to handle air displacement (“breathing”) during grinding and discharge.
Dust-laden air from the mill is drawn into the vent filter for separation.
- The C-Fan provides the required suction.
- A Knife Gate Valve (KGV) is provided for isolation of the filter line during maintenance or cleaning.
- Separated fines fall into the dust collection drum below the filter.
This ensures a clean, dust-free plant environment and prevents sugar dust escape.
Model Description
RIECO offers scalable systems for various production needs:
| Variant | Model | Capacity (Approx.) | Target Fineness |
|---|---|---|---|
| SU-2DH-SS304 | 2DH SS 304 | 250-300 Kg/hr | 95% 150 Microns |
| SU-2DH-SS316 | 2DH SS 316 | 250-300 Kg/hr | 95% 150 Microns |
| SU-2W-SS304 | 2W SS 304 | 500-600 Kg/hr | 95% 250 Microns |
| SU-2W-SS316 | 2W SS 316 | 500-600 Kg/hr | 95% 250 Microns |
| SU-BT-SS | UM 450 SS 304 | 1000-1200 Kg/hr | 95% Pass 75 microns |
Key Components
| Component | Function | Technical Feature |
|---|---|---|
| Feed Hopper | Holds and regulates the incoming S30 sugar before entering the mill | Designed for steady gravity flow; food-grade SS construction; allows integration of controlled feeding devices |
| Screw Feeder / Feed RAL | Provides controlled, uniform feeding into the mill | Adjustable feed rate; avoids overloading; acts as air-seal when RAL is used |
| Micro Pulveriser / Universal Mill (BT-450) | Primary size reduction of S30 sugar to required mesh | Impact + milling action; low-heat grinding; suitable for 250 micron in Pulverizer & 75 Universal mill output; robust rotor/liner configuration |
| Gravity Discharge Hopper | Collects and buffers ground sugar directly below the mill | Vertically aligned design; prevents surging; smooth flow of fine powder |
| Product RAL (Below Discharge Hopper) | Ensures sealed, controlled discharge of final product | Prevents air leakage; maintains consistent product flow; supports dust-free operation |
| Vent Bag Filter | Handles mill breathing, separates air–dust mixture, and recovers sugar fines | Pulse-jet cleaning; high filtration efficiency; hygienic dust control; food-grade internal surface |
| Centrifugal Fan (C-Fan) | Creates suction for dust collection and airflow through vent filter | Maintains required negative pressure; stable airflow; ensures clean plant environment |
| Knife Gate Valve (KGV) | Isolates duct line during cleaning or maintenance | Quick shut-off; SS construction; prevents backflow of dust-laden air |
| Dust Collection Drum | Collects dust/fines separated from the vent filter | Compact design; easy handling; recovers fine sugar that would otherwise be lost |
| Ducting & Interconnections | Connects mill, hopper, C-Fan & vent filter | SS304/food grade material; smooth internal finish; leak-proof airflow paths |
| Control Panel / Local Control Box | Controls operation of feeder, mill, fan, and RALs | Basic interlocks; overload protection; feeder speed control; ensures safe & synchronized operation |
Features & Benefits
- Anti-Caking Operation
- Explosion Safety
- Cool Grinding:
- Hygiene
- Low Dust & Hygienic Operation
The integration of dehumidified air prevents the sugar from absorbing moisture, ensuring a free-flowing final powder that doesn't lump in the bag.
Fully compliant with ATEX / NFPA standards.12 Features include 10-bar shock-resistant construction (optional), chemical suppression systems, and mechanical isolation valves.
High airflow design keeps the temperature rise low (< 10°C), preserving the whiteness and quality of the sugar.
SS304/316L construction with food-grade polishing and easy-clean designs (CIP capable) ensures compliance with FSSAI and FDA standards.
Vent bag filter with C-fan maintains dust-free environment, essential for food-grade applications.
Applications
- Bakery: 150–250 micron sugar for biscuits and cookies.
- Confectionery: "Icing Sugar" for dusting, cream fillings, and fondants.
- Beverages: Fine dissolving sugar for instant drink mixes.
- Pharma: High-purity sucrose powder for tablet coating and syrups.
Model Variants
| Variant | Model | Capacity (Approx.) | Target Fineness |
|---|---|---|---|
| SU-2DH-SS304 | 2DH SS 304 | 250-300 Kg/hr | 95% 150 Microns |
| SU-2DH-SS316 | 2DH SS 316 | 250-300 Kg/hr | 95% 150 Microns |
| SU-2W-SS304 | 2W SS 304 | 500-600 Kg/hr | 95% 250 Microns |
| SU-2W-SS316 | 2W SS 316 | 500-600 Kg/hr | 95% 250 Microns |
| SU-BT-SS | UM 450 SS 304 | 1000-1200 Kg/hr | 95% Pass 75 microns |
Technical Parameters
| Parameters | Details |
|---|---|
| Feed Material: | Crystal Sugar S 30 grade |
| Fineness | Adjustable from 150 microns 250 microns |
| Feed Moisture | Recommended < 0.05%. |