GB1343729A - Vortex clarifer - Google Patents

Abstract

1343729 Centrifugal separators QUEEN'S UNIVERSITY AT KINGSTON 19 April 1971 [8 May 1970] 27129/71 Heading B2P Heavy and light fractions of a fluid (as hereinafter defined) are separated by supplying the fluid to one end of an annular separating zone formed between two cylindrical surfaces rotating in synchronism; establishing circulation of the fluid in the separating zone in the form of substantially a forced vortex thereby producing vortical separation of the fluid fractions and imparting an axial velocity to the fluid whereby the heavy and light fractions are separated. The term "fluid" is defined as including particulate solids, liquids and gases and mixtures thereof which exhibit properties of a fluid. In Fig. 1, a separator for treating liquid containing fine sediment comprises a stationary outer casing 30, 31, 32 to which are respectively connected, via bearing sections 33, 34, inlet and outlet vortex chambers 35, 36. Mounted within the casing is a rotatable assembly comprising a tubular cylinder 10 connected to vaned hollow conical portions 11, 12 terminating in cylindrical sections 13, 14 which have a number of holes 23, 25 and are mounted in plastics bearing sleeves 26, 27 press fitted in the bearing sections 33, 34. A central tubular support member 17 defines with the cylinder 10 an annular separating chamber 24. The member 17 is connected to hubs 28, 29 between which and the conical portions 11, 12 extend impeller blades 20, 21. The hubs 28, 29 are welded to spindles 15, 16, the spindle 15 being connected to a drive pulley or electric motor. In operation, sediment-containing liquid is supplied to vortex chamber 35. Any gases present escape from the liquid through a venting tube 39. The liquid having acquired angular momentum passes down the holes 23 between the blades 20 which impart further momentum to it so that it rotates at the same anngular velocity as the inner and outer walls of the chamber 24 thus forming a forced vortex. As the liquid moves downwards in the chamber 24, the heavier sediment migrates to and accumulates on the outer wall while the centrifuged liquid passes further down between the blades 21, which extract energy from the rotating liquid, and through the holes 25 into the vortex chamber 36 from which it is discharged under pressure through a pipe 38. The sediment is removed from the chamber when rotating of the separator is stopped. Gases separated out in the chamber 24 escape through passageways 22 formed in the hub 28. To overcome turbulence in the liquid leaving the pockets between the inlet blades 20, a perforated plate may be fitted below the blades upstream of the separating chamber 24. Alternatively, the pockets may be provided with a filling of friction packing held in place by a screen to force the fluid to follow the rotation of the inner and outer walls of the pockets.