High velocity hot air impingement dryer is used to dry a water-based silicone finish on a spun-bonded polyester nonwoven web that is 210" wide. The gas-fired dryer system from Glenro Inc. has nozzles mounted beneath the product to apply hot air to the web at a right angle. Hot air impingement breaks through the boundary layer of air that surrounds the moving web and transfers heat to the product, vaporizing liquids in the coating or finish. The turbulence created also helps exhaust vapor from the process, further speeding drying.
September 2000, RS# 202