Uniflow cyclone

There are two primary types of cyclones the reverse-flow cyclone and the uniflow cyclone. The reverse-flow (Fig. 1) is by far the most common. It is called a reverse-flow cyclone because the gas-solids mixture enters the cyclone tangentially at its periphery, spirals around the barrel, and then the gas reverses flow and exits through a gas outlet tube (also called the vortex finder or the vortex tube) at the top of the cyclone. The solids spiral down around the barrel of the cyclone at an angle of approximately 15 degrees and enter the cyclone cone attached to the bottom of the barrel. The solids exit the reverse-flow cyclone at the bottom of the cyclone cone. 

Figure 2 Schematic drawing of uniflow cyclone and multiclones.

Gauthier TA, Brians CL, Bergougnou A, Galtier P. Uniflow cyclone efficiency study. Powder Technol 62 217-225, 1990a. 

Gauthier TA, Briens CL, Crousle O, Galtier P, Bergougnou MA. Study of the gas circulation patterns in a uniflow cyclone. Can J Chem Eng 70 209-215, 1992. 

To separate particles from gaseous streams, cyclones are frequently used in large-scale practices. In fact, cyclone based dust collectors are one of the most widely used devices for removing larger-sized particles. Virtually all cyclones used industrially are reverse-flow cyclones. There are two other types of cyclones rotary-flow (CiUberti and Lancaster, 1976a, b) and uniflow (Ter Linden, 1949). Only the reverse-flow cyclone will be considered here. 

The cyclone models illustrated above are meant merely to introduce the reader to the complex subject of particle separation from gases by cyclones. More interested readers should pursue the original references, as well as the brief overview on devices, in Perry and Green (1984, pp. 20-83-20-89). A model of particle separation in a down-exhaust cyclone separator, of uniflow type, is available in Chen et aL (1999b). These separators have a very low gas pressure drop. 

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