WOLFF GROUP supplied a manufacturer of high quality self-adhesive labels with a filter unit to remove various resin dusts. Since the process involves highly explosive dusts (maximum rate of pressure rise in dust explosion KST = 315 m·bar/s, and minimum ignition energy is MIE = 1-3 mJ), a dedusting unit with panel filters with antistatic properties was suggested, which allowed using explosive panels placed on the roof of the unit. Such a construction made it possible to vent the explosion upwards, without the necessity of defining a safety zone around the venting system.
High KST also necessitated the use of explosion cut-off in the form of HRD bottles on the pipeline. The last stage was to supply an Ex ventilation fan to zone 22.
The above-mentioned filter unit consists of 2 modules. There are 4 filter panels with the area of 7.4 m2 for each module, which gives the filtration area of 59.2 m2. Since dust may exhibit adhesive properties, the filtration material used is polyester fleece with GORE membrane, which facilitates the cleaning process and reduces adhering the dust to the filter material. Moreover, all the panels have adequate earthing.
Fig. 1. Visualisation of the modular filter. Source: WOLFF GROUP.
Immediately under the decompression panels, which were installed on the unit roof, a suitable space was provided, allowing free outflow of explosion, which may occur in the filter chamber.
The supplied deduster is part of our new line of modular filter units, which shows that development of such devices was a good decision. It increases competitiveness of our solutions on the tough market of broadly understood filtration.
The filter was first presented in Poland during the 3rd International INDEX Conference on industrial explosion and process safety. The unit was also presented at SCHÜTTGUT | SOLIDS 2015 Fair in Dortmund.
Fig. 2. Demonstration modular filter presented during a fair in Dortmund. Source: WOLFF GROUP.
SCOPE OF WORKS: selection and supply of a filter unit for separating resin explosive dusts
LOCATION: Poland, Lower Silesia Province