Super Air Knives Used as a Non-Contact Barrier in a Non-Woven Application

An overseas customer manufactures a 2.2 meter wide non-woven material.  In one of their processes, the media would travel through a spray booth to apply a water-based surfactant.  The surfactant was atomized and blown onto the top and bottom of the material.  The spray booth was equipped with a fume hood to capture any excess mist.  The material would then travel out of the spray booth and into the oven to dry.

Area between Spray Booth and Oven
Area between Spray Booth and Oven

Because they were running at a speed of 160 m/min, a draft was being created as the media was exiting the spray booth.  This draft was strong enough to overcome the vacuum pressure from the fume collection system.  This would allow the excess mist to escape the spray booth.  It was then collecting on the surface of the oven and floor outside the containment area.  This created a safety issue as well as a large mess.

In looking at the problem area, the dimension of the opening of the spray booth was 2.65 meters by 300 mm.  To blow a good curtain of air to contain the mist, we needed to have a laminar flow to create that “wall”.  I recommended two pieces of a model 1102108 Super Air Knife Kits.  At 108” (or 2.74m) long, they are the longest Super Air Knives in the market.  With a steady flow of air along the entire 2.74 meter length, it can generate that curtain of air across the entire opening of the spray booth.  The laminar flow was key as they did not want to disturb the spraying nozzles inside the booth.

The Super Air Knife Kit also comes with a filter, a regulator, and a shim set.  With the included shim set, the force can be changed dramatically by using a different thickness of shim.  Since they did not need much force to keep the mist inside the spray booth, they opted to put a thinner shim inside the Super Air Knife.  This would reduce the amount of compressed air needed, and with a regulator, the customer could “dial” in the correct amount of force to create the proper air barrier.  The Super Air Knives were mounted above and below the material to blow directly across the opening of the spray booth.  Any fine mist that would come in contact with the air would be deflected back into the spray booth.  With the extra mist removed from the process, the fume extraction system could then perform its duties the way it was intended. With air being used to create that barrier, it did not disrupt the structure of the material or the surfactant on its surface.

Super Air Knife
Super Air Knife

If you require a non-contact barrier for your application, EXAIR Super Air Knives could be your solution.  For this customer, we were able keep the work place safe and mess-free.

 John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb