Abstract: A feeder is disclosed for introducing slug of a particulate material into a gas stream. The feeder is characterized by a valve member positioned in a housing and movable from a first position to a second position and from a second position to a third position. A first passsage through the valve member connects to an inlet port of the housing when the valve member is in first position. The first passage connects the second inlet port to the outlet port when the valve member is in the second position. A second passage through the valve member which is isolated from the first inlet port throughout operation connects the second inlet port to the outlet port when the valve member is in third position. In a preferred embodiment, the rotor of a rotary feeder is provided with alternating bores and channels parallel to the longitudinal axis of the rotor circumferentially spaced apart inwardly from the surface of the rotor.

Abstract: An apparatus for intermittently feeding a solid particulate material, in which a measured quantity of the particulate material is periodically fed into a cavity of predetermined volume and the particulate material is thereafter discharged from the cavity, substantially all of the particulate material is removed from the cavity by scraping the particulate material from the cavity simultaneously with the discharge of the material from the cavity.