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Cyclones, Cyclonic separation and Wear

Cyclones, Cyclonic separation and Wear

Cyclone separators or simply cyclones are among the most commonly utilized devices with the purpose of removing solid particles from a gas stream. Various operation demands dictate the use of such devices in multiple processes across many different industries like cement, energy, wood processing and others. Cyclones are used frequently as part of pneumatic conveyor systems to separate coarser from finer materials or to separate materials from the flow of air when they reach their final destination. They are also used as filtration units in air pollution control systems. One such application can be found in coal fired boilers where cyclones are used to remove flying ash that remains in suspension with flue gases.

Cyclones rely on centrifugal force to separate solid particles from the gas stream. The 2 phase solid-air mixture enters the cyclone tangentially through the inlet opening. The curved walls of the cyclone convert the linear motion of the mixture into a double spiral vortex. The main or primary vortex spirals downwards, causing most of the higher density particulates to strike the outside wall. Due to friction, these particulates lose speed and slow down until they eventually fall into a container below trough a hopper.  A secondary vortex swirling upwards is created near the bottom of the cyclone. Lighter components having smaller inertia are carried by this vortex through the center of the cyclone and out the top.

 

There are many advantages in using a cyclonic separator. A simple design with no moving parts, low energy consumption and unobtrusive high temperature function are some of these advantages, just to name a few. However, due to the nature of the cyclonic movement the walls of the cyclone are subject to extensive abrasive wear especially in cases of high hardness particles. One way to overcome this shortcoming is to utilize carbide overlay plates in the manufacturing process. Fabricating a cyclone entirely from carbide overlay Wear plates or lining the walls of an existing cyclone with specially designed wearlinings can vastly extend its operational lifetime.

Cerametal as an expert manufacturer of Wear Solutions has produced cyclones of various sizes and configurations over the years.

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