AIR EXTRACTION AND FILTRATION

The client specialises in the welding of large-scale sheet metal pressings. Although the production hall was equipped with an industrial filtration system,

• the filter units were poorly designed (cartridge filters => frequent blockages)
• the small stationary filtration units were unsuitable in terms of both their location and their ability to capture and extract smoke and fumes
• the central filtration system was under-specified in terms of capacity

Cipres drew up a design for a new industrial extraction system based on ceiling-mounted, zone-specific extraction. The newly installed filtration units helped to extract welding fumes and smoke at a flow rate of Q = 270,000 m³/h.

The centrifugal fans are situated on the floor in separate soundproof enclosures. Clean, filtered air can either be recirculated back into the working environment or discharged outside the building. The ratio depends on the current requirements and settings.

Part of the air is diverted through a heat recovery unit. Dust is conveyed via a rotary feeder into the pneumatic waste transport system, where it is collected in a BigBag. The pneumatic transport system is driven by a small transport fan.

The addition of lime sorbent to the dirty side of the air duct modifies the physical properties of the dust, reduces the sulphur oxide content and improves regenerability.

Residual emissions of 0.1–0.5 mg/Nm³ are well below the required limits. The service life of the filter media, at approximately 20,000 operating hours, exceeds standard warranty specifications.

Operating conditions are 24/7; the project was delivered on a ‘turnkey’ basis.

Ing. Přemysl Pazdera