CASE STUDY
ATEX Centralized Vacuum Systems for Grain Mills and Flour
Keeping an industrial grain mill clean is critical. Flour dust is highly combustible, and any accumulation on floors, structures, or equipment increases the risk of explosion and fire. At the same time, grain and flour residues affect hygiene, attract pests, and can compromise product quality and brand reputation.
This case study describes how Depureco engineered an ATEX-certified centralized vacuum system for a five-floor grain mill in Poland, using a PUMA 15 ATEX central vacuum unit, dual pipelines, and an explosion isolation flap to keep the entire building clean and safe.
Why Cleanliness Matters in Grain Mills
In a grain mill, effective housekeeping is directly tied to safety and product quality:
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Explosion risk reduction
Flour dust is a combustible dust. By regularly removing deposits and preventing dust build-up, the risk of explosive dust clouds or ignition is greatly reduced. -
Production efficiency
Keeping floors and equipment clean helps prevent dust-related disturbances and unplanned downtime on machinery. -
Hygiene and pest control
Less residual grain and flour means fewer insects and rodents, supporting food safety certifications and audits. -
Product quality
A cleaner environment reduces foreign bodies and cross-contamination in the final product. -
Better air quality for workers
Lower dust levels improve indoor air quality and reduce respiratory stress for operators.
An ATEX centralized vacuum system lets the plant deliver these benefits consistently across all floors and process areas.
Customer Profile & Application
The customer is an industrial grain mill in Poland, operating a five-story facility where grain is stored, processed, and converted into flour.
The mill needed a vacuum system that could:
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Collect flour dust, grain, and residues from floors, walkways, platforms, and around milling equipment.
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Serve all five floors, including additional rooms on the first and top floors.
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Operate safely in a Zone 22 combustible dust environment.
The goal was to install a system capable of collecting dirt and flour from the working environment and conveying it into a central vacuum container, improving cleanliness and safety throughout the building.
The Challenge: Combustible Flour Dust in a Multi-Floor Plant
This project combined several challenging factors:
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Combustible flour dust
Fine flour particles can easily become airborne and, when mixed with air in the right concentration, form an explosive atmosphere. Deposits on beams, ledges, and equipment can be re-suspended and ignited. -
Vertical layout across five floors
The mill spans multiple levels, with dust accumulating on stairs, platforms, mezzanines, and process equipment distributed from bottom to top. -
Hygiene and food safety
Grain and flour residues create a favorable environment for pests and undermine hygiene standards. -
ATEX and safety compliance
All equipment must be ATEX-certified and arranged to minimize ignition sources, contain potential explosions, and prevent flame propagation through pipes and equipment.
The mill therefore required a central vacuum system capable of serving the entire vertical layout, using ATEX-compliant components and proper explosion protection devices.
Depureco Solution: ATEX Central Vacuum System for a Five-Floor Grain Mill
Depureco designed an ATEX-certified central vacuum cleaning system specifically for this five-floor grain mill.
The system is built around:
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ATEX-compliant pipelines and suction inlets distributed across the building.
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A dedicated explosion isolation flap to protect the system.
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With this configuration, operators can perform regular maintenance cleaning on all floors using a single, safe vacuum hub.
System Configuration & Installation Features
Pipelines & Suction Inlets
The centralized vacuum system includes:
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Two main pipelines
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One pipeline on each side of the building.
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This layout minimizes pipe runs while ensuring coverage of all process areas.
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Ten standard suction inlets
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Each pipeline is equipped with one suction inlet per floor, giving a total of 10 inlets across the five floors.
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One extra inlet on the first floor.
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One extra inlet on the top floor.
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These inlets are dedicated to cleaning extra rooms or areas with higher dust accumulation.
Two additional suction inlets
In total, the system features 12 suction inlets, strategically located to cover the entire building with maximum accessibility and minimum piping.
Explosion Isolation Flap
Collection and Cleaning Process
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Installed in the duct line to isolate the vacuum unit from the piping.
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In the event of an explosion or flame front in the ductwork, the flap closes and prevents flames from propagating back toward other parts of the plant.
Together with ATEX-certified components and antistatic accessories, this device enhances safety when handling combustible flour dust.
All collected grain, flour, and dust are conveyed through the pipelines and discharged directly into the central vacuum container of the PUMA 15 ATEX unit.
Operators simply:
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Connect a flexible hose to the nearest suction inlet.
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Vacuum floors, platforms, equipment, and hard-to-reach areas.
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Allow the system to transport the material safely into the central collection container, where it can be handled according to the plant’s waste and recycling procedures.
Depureco PUMA 15 ATEX Central Vacuum Unit
At the heart of the system is the Depureco PUMA 15 ATEX, a high-power industrial vacuum designed for combustible dust and ATEX Zone 22 environments, with an internally certified chamber.
Key Safety & Performance Features
The PUMA 15 ATEX used in this installation includes:
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ATEX-certified side channel blower
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Approximately 11 kW three-phase blower.
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Provides the vacuum and airflow required for multi-floor, long-distance cleaning.
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ATEX 1/3D marking and internal Z20 certification
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Suitable for use in Zone 22 environments.
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Z20 internal chamber certification ensures it safely handles combustible dust directly inside the vacuum.
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Antistatic filtration with automatic cleaning
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Large-surface antistatic filters for effective dust capture.
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SP automatic filter cleaning system to maintain performance and reduce manual filter maintenance.
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AISI304 stainless steel collection container
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Robust AISI304 stainless-steel bin, ideal for food environments and easy to clean.
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Ensures durability and resistance to corrosion.
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Built-in flameless vent
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Integrated flameless venting designed to contain flame and over-pressure in the event of a possible explosion inside the unit.
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Antistatic accessories
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Hoses, tools, and fittings are antistatic to avoid electrostatic discharges and ignition risks during vacuuming.
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These features make the PUMA 15 ATEX a strong, safe choice for cleaning grain, flour, and other combustible dusts in multi-floor grain mills.
ATEX-Certified Channel Blower
Antistatic Wide Surface Filters
AISI304 Stainless Steel Container
Flameless Vent
Results & Benefits for the Grain Mill
With the ATEX centralized vacuum system in place, the grain mill achieved:
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Lower explosion risk
Flour dust deposits are removed more frequently and more effectively across all five floors, helping reduce the likelihood of explosive conditions. -
A cleaner and safer facility
Suction inlets on every floor, plus additional inlets in key rooms, make it easy for operators to keep silo floors, platforms, and production areas clean. -
Less downtime and fewer malfunctions
Clean equipment and environments reduce dust-related malfunctions and unplanned maintenance on machines and electrical components. -
Improved hygiene and food safety
Reduced dust and grain residues support better hygiene standards and help meet food safety requirements. -
Better working conditions
Lower dust levels result in improved air quality and more comfortable working conditions for employees throughout the mill.
Why ATEX Central Vacuum Systems Matter for Grain & Flour
For grain mills, flour producers, and other facilities handling combustible powders, cleaning is a core safety function—not just housekeeping.
An ATEX-certified central vacuum system:
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Provides a structured cleaning network that reaches all floors and process areas.
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Uses certified, antistatic components and explosion protection devices to safely manage combustible dust.
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Supports compliance with ATEX, NFPA, and other combustible dust standards.
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Helps plants stay safe, efficient, and ready for inspections and audits.
Talk to Depureco USA About Grain Mill & Combustible Dust Solutions
If you operate grain mills, flour plants, or other food facilities with combustible dust, Depureco USA can help you design an ATEX/NFPA-aligned central vacuum system tailored to your building, production lines, and risk profile.
We can combine:
- ATEX-rated suction units like the PUMA ATEX range,
- Pre-separators and accessories optimized for combustible dust,
- And customized multi-floor piping layouts for silos and production buildings.
Get in touch with Depureco USA to discuss your grain or flour application and build a safer, more efficient cleaning system for your facility.