Feeding particulate matter

Claim 1

A method of feeding finely divided reduction-grade alumina to a plurality of aluminum reduction cells, each of said cells having at least one feeding device with a supply hopper associated therewith which feeds discrete quantities of alumina to the reduction cells comprising a. feeding finely divided alumina from a source thereof to a primary air-activated gravity conveyor system; b. fluidizing the alumina in the primary air-activated gravity conveyor system and continuously maintaining the primary air-activated gravity conveyor systems essentially full of fluidized alumina; c. transferring alumina from the primary air-activated gravity conveyor system to a plurality of secondary air-activated gravity conveyor systems; d. fluidizing alumina in the secondary air-activated gravity conveyor systems and continuously maintaining the secondary conveyors essentially full of fluidized alumina; e. transferring alumina from the secondary air-activated gravity conveyor systems to the supply hoppers associated with the feeding devices and maintaining the level of alumina within the feed hoppers at a desired level so that when one or more of the feeding devices feed discrete quantities of alumina to a reduction cell, the supply hopper is refilled with alumina from the secondary air-activated gravity conveyor system, the secondary air-activated gravity conveyor system is refilled with alumina from the primary air-activated gravity conveyor system and the primary air-activated gravity conveyor system is refilled with alumina from the alumina source.

Claim 2

A method of feeding finely divided reduction-grade alumina to a plurality of aluminum reduction cells, each of said cells having at least one feeding device with a supply hopper associated therewith which feeds discrete quantities of alumina to the reduction cells comprising a. feeding finely divided alumina from a source thereof to a primary air-activated gravity conveyor system; b. fluidizing the alumina in the primary air-activated gravity conveyor system and continuously maintaining the primary air-activated gravity conveyor systems essentially full of fluidized alumina; c. transferring alumina from the primary air-activated gravity conveyor system to a plurality of secondary air-activated gravity conveyor systems; d. fluidizing alumina in the secondary air-activated gravity conveyor systems and continuously maintaining the secondary conveyors essentially full of fluidized alumina; e. transferring alumina from the secondary air-activated gravity conveyor systems to the supply hoppers associated with the feeding devices and maintaining the level of alumina within the feed hoppers at a desired level so that when one or more of the feeding devices feed discrete quantities of alumina to a reduction cell, the supply hopper is refilled with alumina from the secondary air-activated gravity conveyor system, the secondary air-activated gravity conveyor system is refilled with alumina from the primary air-activated gravity conveyor system and the primary air-activated gravity conveyor system is refilled with alumina from the alumina source.

Claim 6

A system for transferring finely divided particulate matter from a source thereof to a plurality of discharge points, each of said discharge points having a feeding device associated therewith for feeding discrete quantities of particulate matter comprising a. a primary fluidizing conveyor system which receives particulate matter from said source and which is provided with means to fluidize particulate matter received from said source to cause said fluidized particulate matter to flow within the primary fluidized conveyor system and to continuously maintain the primary fluidizing conveyor system essentially full of fluidized particulate matter; b. a plurality of secondary fluidizing conveyor systems which receive particulate matter from the primary fluidizing conveyor system and which are provided with means to fluidize particulate matter therein, to cause the said fluidized particulate matter to flow within the secondary fluidizing conveyor systems and to continuously maintain the secondary fluidizing conveyor essentially full of particulate matter; and c. hoppers associated with the feeding devices to supply particulate matter thereto which receive particulate matter from the secondary fluidizing conveyors and which are provided therein with open-topped fluidizing conveyors in fluid communication with the secondary fluidizing conveyors to feed particulate matter to the inner chamber of said hopper.

Claim 7

A system for transferring finely divided particulate matter from a source thereof to a plurality of discharge points, each of said discharge points having a feeding device associated therewith for feeding discrete quantities of particulate matter comprising a. a primary fluidizing conveyor system which receives particulate matter from said source and which is provided with means to fluidize particulate matter received from said source to cause said fluidized particulate matter to flow within the primary fluidized conveyor system and to continuously maintain the primary fluidizing conveyor system essentially full of fluidized particulate matter; b. a plurality of secondary fluidizing conveyor systems which receive particulate matter from the primary fluidizing conveyor system and which are provided with means to fluidize particulate matter therein, to cause the said fluidized particulate matter to flow within the secondary fluidizing conveyor systems and to continuously maintain the secondary fluidizing conveyor essentially full of particulate matter; and c. hoppers associated with the feeding devices to supply particulate matter thereto which receive particulate matter from the secondary fluidizing conveyors and which are provided therein with open-topped fluidizing conveyors in fluid communication with the secondary fluidizing conveyors to feed particulate matter to the inner chamber of said hopper.