Dispersoid separation method and apparatus

Apparatus for removing entrained particulate matter in the range of from five to ten microns from combustion gases produced in the burning of powdered coal, comprising:

• means defining a cylindrical housing having an elongated vertical axis;
• partition means, comprising a plurality of impervious wall members, for dividing the interior of said housing into a plurality of axially-extending coextensive, substantially unobstructed, annular and concentric through passages around in parallel forming annular collecting surfaces;
• inlet means for directing tangentially into the lower end of said housing and said passages a flow of said combustion gases at a selected angular velocity sufficient to produce a centrifugal force on said entrained matter capable of driving said matter radially;
• means for rotating said partition means around said axis at substantially said angular velocity so as to minimize the velocity difference between said gases and said surfaces and forming boundary layers of sufficient thickness to shield collecting material from the influence of the flowing gases to permit collection of substantially all of said entrained particulate matter;
• hopper means located within said housing below said inlet means for removing particulate matter collect on said surfaces when flow through said apparatus is terminated;
• and
• outlet means at the upper end of said housing for carrying away said gases after removal of said particulate matter.