The key to better filter life is to reduce the velocity of solids and gasses. The way to reduce velocity is to introduce diffusion on the inlet side.
Dust collectors (fabric filters) are prevalent in industrial air pollution control and material recovery. These filters encounter numerous problems with abrasion, poor discharge of collected material, high pressure drop and short filter life.
The commonly used hopper inlets, though an effective and simple design, suffer from abrasion by particulate matter, poor material discharge and turbulent air. The results are usually increased pressure drop and reduced bag life. The stress placed on the filter media and the collector mechanism causes increased costs to operate, reduced usable life and potential safety concerns.
The Nederman MikroPul Cascadair™ inlet gas diffuser consists of a series of orifice plates, with the I.D. and O.D. of the plates reducing in size in progression from the inlet opening to the opposite side of the hopper. The effect of the Cascadair is to distribute the incoming gas stream, and its entrained solids, equably to the whole filter array.
It also serves to lower the gas velocity approaching the filters and all areas of the filter housing. Lower and even gas velocity throughout the filter lessens turbulence among the filters and in the hopper
- Reduce impact velocity of abrasive particles.
- Reduce turbulence among the filters to allow particles to easily fall into the collection hopper.
- Reduce filter pressure drop. Less turbulence prevents the re-entrainment of the particles during pulse cleaning and thus reduces the net material load on the filters. Less material load results in less filter cake, and therefore lower pressure drop across that filter cake.
The Cascadair, while originally developed for pulse-jets, can improve performance of any fabric filter with a hopper inlet. This includes pulse-jet, shaker or reverse-air/gas designs.
Cascadair can be easily installed as a retrofit to existing collectors with minimal disruption to plant operations.