Flexible packaging extruder and other process lines commonly emit very fine, white smoke from die and extruder exhaust points, with emissions from vacuum pumps at times as well. Such extruder smoke emissions can build up to potentially unhealthy levels inside the plant if not exhausted outside the plant. If the extruder smoke is simply exhausted to atmosphere using hoods, ductwork and fans without any air pollution control technology, and specifically without a properly-suited oil mist control unit or particulate matter control device, a significant mess can be created on the roof of the building and/or on surrounding equipment and employees’ cars.
The white smoke emitted from the extrusion lines is typically comprised of submicron-size condensed particulate that can – depending on the process – behave as very fine liquid mist (aerosol) droplets or, in other cases, the condensed mist cools sufficiently to set/harden into a wax-like, semi-solid particulate matter. This type of fine, messy flexible packaging smoke control is among the most challenging applications for air pollution control technologies to handle.
APC’s UHF® filter, however, is an oil mist control and particulate control device ideally suited for the fine white, oily smoke and aerosol emissions given off at flexible packaging plants, providing the Owner with the high removal efficiency on the smoke that a top-performing baghouse or cartridge collector would provide, but without the plugging problems that those devices have with liquids and semi-solid particles. The UHF® filter unit is an air pollution control technology and particulate matter control device that is completely unique in the industry while also long proven.
The UHF® filter media is designed to get saturated and very dirty with liquids and solids – whatever mess is thrown at it – but instead of trying to pulse or otherwise clean the collected extruder smoke off, which cannot be done by a conventional particulate matter control device when dealing with oily/sticky smoke, the UHF® filter unit provides oil mist control and particulate control on this type of smoke by simply advancing a short section of fresh media into the filter chamber, and the soiling process begins again. Solid particulate is collected in/on the filter media and oils are collected and evacuated via drains on the unit.
APC’s UHF® filter units are successfully collecting extruder smoke in flexible packaging plants for some of the largest packaging companies all over North America, with many units in service in these challenging applications for going on 20 years. Many of the plants run their process lines 24/7, for which the UHF® filter unit is well suited as filters are easily changed in 5 minutes or so without any process line or exhaust system downtime at all. Filter media usage in these plants is typically low and cost effective.