Imperforate bowl: centrifugal separators – Rotatable bowl
Patent
1990-11-01
1992-11-03
Coe, Philip R.
Imperforate bowl: centrifugal separators
Rotatable bowl
B04B 100
Patent
active
051603098
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a centrifugal separator for separation of solids from a suspension, comprising a rotor that forms a separating chamber having a central part and a peripheral part, means defining within the rotor a central chamber and a channel, which latter connects the central chamber with said peripheral part of the separating chamber, a first part of the channel close to the central chamber extending substantially parallel with the rotor axis, and a second part of the channel forming an angle with the rotor axis and extending from said first channel part to the peripheral part of the separating chamber.
A centrifugal separator of this kind is disclosed for instance in U.S. Pat. Nos. 3,752,389 and 4,525,155.
A problem in connection with operation of a centrifugal separator of this kind is that solid particles in the treated suspension are entrained by liquid into said channel and are depositing on the radially outer wall of said first part of the channel extending substantially in parallel with the rotor axis. In certain cases it has proved that such depositing of particles has entirely, or to a substantial degree, blocked liquid flow through the channel and, thereby, jeopardized the intended function of the centrifugal separator.
As can be seen from said patent specification the channel in question in a centrifugal separator of this kind may have different functions. In the centrifugal separator according to U.S. Pat. No. 4,525,155 the channel is intended to be flowed through intermittently by a relatively heavy liquid that has been separated in the rotor and is to be discharged therefrom. In the centrifugal separator according to U.S. Pat. No. 3,752,389 the corresponding channel is both to be flowed through intermittently by separated heavy liquid to be discharged from the rotor and, substantially continuously, to be flowed through by a small flow of liquid intended for sensing purpose. In both these cases particles will be entrained by liquid from the separating chamber into the channel and deposit on the radially outer wall of said first part of the channel. Since this outer wall has only an insignificant inclination, or no inclination at all, relative to the rotor axis, particle deposits thereon cannot move along the outer wall as a consequence of the centrifugal force. Therefore, they remain and cause clogging of the channel.
A different function of said channel may be to transfer liquid intermittently from a stationary member to the radially outermost part of the separating chamber. Such liquid may be a so called displacement liquid that is supplied to the separating chamber in a certain amount immediately before a brief opening of the peripheral outlets of the separating chamber. It has proved in practice that clogging problems have arisen even in these cases--probably as a consequence of particles having been entrained by liquid from the separating chamber into said channel after each time the peripheral outlets of the separating chamber have been opened. The particles then have deposited on said outer wall in the first part of the channel, where they have remained even during the repeated periods of time when the channel has been emptied of liquid. New particles then have been entrained by liquid from the separating chamber into the channel, etc.
The object of the present invention is to avoid collection of particles in said first part of the channel in a centrifugal separator of the initially described kind.
This object may be obtained in that the centrifugal separator comprises a pumping means, for instance of the kind shown in U.S. Pat. No. 4,525,155, which is arranged during operation of the rotor to pump liquid out of the central chamber and thereby to establish a liquid flow through the initially mentioned channel and into the central chamber, and that this pumping means is arranged to pump liquid from the central chamber to an area in said channel so situated that a circulation of the pumped liquid will come up in a flow circuit comprising said first part of the channel,
REFERENCES:
patent: 4510052 (1985-04-01), Eklof
patent: 4820256 (1989-04-01), Nordstrom
ALFA-Laval Separation AB
Chin Randall E.
Coe Philip R.
LandOfFree
Centrifugal separator with pumping means, arranged to accomplish does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Centrifugal separator with pumping means, arranged to accomplish, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Centrifugal separator with pumping means, arranged to accomplish will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2047268