EP 0583924 A3 19941019 - Elutriation apparatus and method for cleaning granules.
Title (en)
Elutriation apparatus and method for cleaning granules.
Title (de)
Abschlämmungsvorrichtung und Verfahren zum Reinigen von Körnchen.
Title (fr)
Dispositif d'élutriation et procédé pour nettoyer des granules.
Publication
Application
Priority
US 93081192 A 19920817
Abstract (en)
[origin: EP0583924A2] Apparatus for cleaning granules comprises a hollow vertically-disposed elutriation column (A) into which granules, especially small plastic pellets, having adulterating dust, fine particulate and debris entrained therewith are propelled on a stream of ionized air from an upwardly inclined injection tube (B) so that the granules and adulterating dust become temporarily suspended and float within a medial portion of the column (B). Suction imposed from an upper portion of the column (B) draws off the lighter weight particulate at the top of the floating suspension while the larger granules fall to the bottom. Pairs of AC electro-static discharging means (D1, D2) diametrically disposed at opposite portions of the injection tube (20) which is conductive to define a reference electrode isolated from ground are electrically connected to opposite sides of a high voltage AC transformer (G) expose the adulterated granules to a balanced ion emission thereby effecting neutralization and assisting separation of the fines from the coarse granules prior to entry into the elutriation column (A). Fine-from-coarse separation is achieved when the dirty granules with entrained ions are exposed to a high velocity air blast as they are propelled into the elutriation column (B). The entrained ions serve to neutralize the granules and fines suspended within the elutriation column (B) thereby eliminating the possibility of their re-attachment by way of electro-static charging due to friction with the elutriation column wall. A pair of diametrically opposed electro-static discharging means at the lower portion of the elutriation column, which is similarly conductive to define a reference electrode in isolated disposition with respect to ground, are also electrically coupled to opposite sides of a second high voltage AC power supply to provide balanced neutralization of the cleansed granules which are then collected for re-cycling or re-use. <IMAGE>
IPC 1-7
IPC 8 full level
B07B 7/01 (2006.01); B07B 11/02 (2006.01); H05F 3/04 (2006.01)
CPC (source: EP)
B07B 7/01 (2013.01); B07B 11/02 (2013.01); H05F 3/04 (2013.01)
Citation (search report)
- [DXAY] US 3475652 A 19691028 - LEVY WARREN W
- [DYA] US 4299693 A 19811110 - PAULSON JEROME I
- [A] US 2940592 A 19600614 - COWDEN LEWIS M, et al
- [DA] US 3137806 A 19640616 - HAROLD SCHWERINER
- [DA] US 4046492 A 19770906 - INGLIS LESLIE R
Designated contracting state (EPC)
DE ES FR GB IT
DOCDB simple family (publication)
EP 0583924 A2 19940223; EP 0583924 A3 19941019; EP 0583924 B1 19980527; DE 69318774 D1 19980702; DE 69318774 T2 19980924
DOCDB simple family (application)
EP 93306247 A 19930806; DE 69318774 T 19930806