Dust extraction
Bag and cartridge filters with compressed air pulse cleaning, cyclones, pneumatic conveying. ATEX design for combustible dusts.
PROCESS VENTILATION AND DUST EXTRACTION / DESIGN, INSTALLATION, SERVICE
Capture at source.
Before it reaches the hall.
Process ventilation removes dust, fumes, oil mist and VOCs at source, using a fraction of the airflow needed for dilution. We design extraction together with the facility air balance, make-up air and heat recovery; for combustible dusts in ATEX 2014/34/EU design (zones 20/21/22), in clean zones with a 10–15 Pa pressure cascade at ISO 7–8.
Send an enquiry- ATEX Directive
- 2014/34/EU
- Dust / gas zones
- 20, 21, 22 / 0, 1, 2
- Pressure cascade in a clean zone
- 10–15 Pa
- Cleanliness class with VOC extraction
- ISO 7–8
- Fume removal methods
- 4
HAGS / PRODUCTION LINE VENTILATIONSee the project
THE SOLUTION STARTS WITH THE PROCESS
The process sets the design.
Local exhaust ventilation (LEV) captures contamination where it is generated. General ventilation exchanges air for people and is no substitute for extraction.
Local exhaust ventilation (LEV)
Welding and grinding stations, woodworking, loading and transfer of bulk materials.
Fumes and VOCs
Paint shops, screen printing, bonding and curing. 4 treatment methods: activated carbon, scrubber, oxidation (UV, ozone, plasma), thermal or catalytic incineration.
Oil mist
Machining, CNC centres, hardening shops. Extraction with mist separation and heat recovery from the exhaust air.
REQUIREMENT → PARAMETER → DELIVERY → PROOF
Parameters,
not promises.
Every requirement has a parameter, a delivery method and proof that can be checked after commissioning.
| Requirement | Parameter | How we deliver | How we prove it |
|---|---|---|---|
| Combustible dust: wood, aluminium, sugar, flour, plastics | zone 20/21/22, equipment category under ATEX 2014/34/EU, temperature class T | Ex fan, explosion relief vents or explosion suppression, explosion isolation, earthing | explosion risk assessment and explosion protection document for the process |
| VOC extraction inside a cleanroom | ISO 7–8, overpressure of 10–15 Pa relative to adjacent zones | extraction balanced by filtered supply air, cascade logic in the controls | continuous differential pressure measurement with a loss alarm |
| Odours and solvent fumes | 4 methods: activated carbon, scrubber, oxidation, incineration | selected after measuring concentration: activated carbon at low, incineration at high VOC load | concentration measurement at inlet and outlet after commissioning |
| No underpressure in the hall | make-up air equal to the extraction airflow, with heat recovery | facility air balance, heat exchanger on the exhaust, variable speed drives (-20% airflow ≈ -50% power) | measurement of extraction capacity and of the pressure difference between the hall and outdoors |
Why extract at source rather than add more general supply air?
Diluting emissions with more general supply air is the most common mistake in hall ventilation: the concentration across the volume drops, exposure at the workstation stays, and every additional cubic metre of air has to be heated in winter.
Local exhaust ventilation (LEV) captures contamination where it is generated. Effectiveness depends on hood geometry and capture velocity: higher for dry, heavy dust than for light fumes, and different again for hot fumes rising by convection. The design starts from the process and what it emits, not from an air change rate in a table.
When must a dust extraction system be ATEX rated?
Explosion-proof design is required when the dust is combustible, or when the equipment operates in a designated hazardous zone or conveys an explosive atmosphere. Gas zones are designated 0, 1 and 2, dust zones 20, 21 and 22; the lower the number, the longer an explosive mixture is present during the year and the higher the equipment category under ATEX 2014/34/EU.
An Ex fan alone does not make the installation compliant. Compliance covers the whole system (ducts, filter, explosion relief vents or explosion suppression, explosion isolation and earthing), based on an explosion risk assessment and an explosion protection document for the process. Selecting equipment from a catalogue without this assessment usually ends with a finding at acceptance.
What drives the cost of a dust extraction system?
The bill for a dust extraction system is driven by heating the make-up air, not by the fan itself. Without make-up air, underpressure builds up: extraction loses capacity, doors are hard to open, and in winter cold air is drawn into the hall.
We start the design from the balance of the whole facility (together with the cooling and heating systems), with heat recovery from the exhaust through a heat exchanger wherever the nature of the contamination allows. Extraction capacity is tied to the controls: fan power varies with the cube of speed, so reducing airflow by 20% while workstations are idle cuts shaft power by around 50%.
FROM BRIEF TO COMMISSIONING
A coherent design.
Clear next steps.
- 01
Emission survey
Process analysis, measurement of contaminant concentration and composition, workstation geometry. These determine capture velocity and hood shape.
- 02
Facility balance
Extraction airflow, make-up air, heat recovery and an explosion risk assessment for combustible dusts.
- 03
Control and acceptance
Variable speed drives and controls match capacity to the workstations in use. On-site capacity measurement confirms the design assumptions.
BEFORE WE START
Good to
know.
RELATED SOLUTIONS AND PROJECTS
LET’S START WITH YOUR PROCESS
Your technology.
Our engineering.
Describe what your production needs: facility, parameters, deadline.
An engineer replies, not a sales team.