Coalescing Fiberbed Filter Mist Collector Systems
Air Pollution Control Case Studies from Industrial Processing Plants
Coalescing Fiberbed Filter Mist Collector Systems have been around for many years controlling “Air Pollution” from industrial process manufacturing processes. Several types of Coalescing Fiberbed Filter Mist Collector Systems currently are available on the Market. The application of certain basic design parameters varies from vendor to vendor, however the majority of the systems are designed for the highest removal efficiency.
Coalescing Fiberbed Filter Mist Collector Systems are designed to capture and collect liquid mists and submicron particles from industrial process exhaust. These emissions are referred to as “smoke” or “blue” haze and are made up of liquid and solid particulate predominately in the submicron size range.
Coalescing Fiberbed Filter Mist Collector Systems use the field-proven processes of Impaction, Interception, and Brownian Diffusion:
Impaction occurs when particles in the <4 micron range is carried via inertia until they strike a filter fiber and are collected.
Interception occurs when particles in the 1to 3 micron range, which typically possess less momentum, follow the air stream until they deviate and graze the side of a filter fiber, removing them from the air stream.
Brownian Diffusion is submicron particles (<1micron) that contain very little mass and follow the air stream. As the air cools, random movement of particles slow down as they collide and coalesce until increasing in size enough to be filtered via impaction/interception. Fiberbed Filters Mist Collectors work to eliminate opacity and other industrial air pollution problems.
Oils and other materials must be condensed from a vapor to a liquid state before they can be collected. Cooling of the exhaust to about 120ºF is typically adequate to condense all of the material. If the exhaust is at or below this temperature, no auxiliary cooling is required. Performance will decline if the operating temperature increases operated above 120oF.
In case where the operating temperature is above 120oF, a cooling system is required. There are several methods of cooling the exhaust: aerobatic cooling; air-to-air cooling; and air-to-water cooling.
In most cases, the stack opacity is reduced to 5% or less, which is generally not visible to the naked eye.
How it Works:
The dirty process exhaust enters the system by means of an induced draft blower.
If cooling is required (temperatures >120oF), the dirty process exhaust enters the cooling system and reduces the temperature to <120oF.
The cooled process exhaust flows through the main fiberbed filters, where the submicron particles are removed. Captured liquids drain from the filters and leave the system through a drain in the vessel sump.
The cleaned process exhaust exits through the top of the Coalescing Fiberbed Filter Mist Collector Systems, going out through the transition duct and I.D. fan.
The clean process exhaust air exits the fan to the atmosphere.