Injection system and method for feeding particulate to a process vessel

An injection system for feeding a particulate material to a process vessel, comprising:

• a sweep stream source;
• a rotor housing having a rotor receiving chamber therein and a sweep chamber associated with the rotor housing;
• a rotor, rotatably disposed within the rotor receiving chamber of the rotor housing, the rotor having at least one cavity adapted for receipt of a predetermined volume of particulate,
• the rotor having a first position for receiving the predetermined volume of particulate and a second position for releasing the predetermined volume of particulate to the sweep chamber of the rotor housing,
• the rotor further having a drive mechanism disposed in engagement therewith for rotating the rotor between the first and second position;
• a sweep stream port disposed in fluid communication with the sweep chamber of the rotor housing for providing a sweep stream to the sweep chamber of the rotor housing, the sweep stream having flow in a direction generally towards the rotor to remove particulate from the rotor cavity.

A method of injecting particulate into a process vessel, comprising the steps of:

• providing a metering device disposed between a particulate storage vessel and a sweep chamber, the metering device having a rotor with a cavity formed therein;
• providing a sweep stream directed generally toward the rotor;
• rotating the rotor to a first position for receiving a predetermined volume of particulate stored in the particulate storage vessel;
• and
• rotating the rotor to a second position for releasing the predetermined volume of particulate to the sweep chamber,
• whereby the sweep stream will remove substantially all of the particulate material from the cavity formed in the rotor when the rotor is in the second position.