Centrifuge having axially movable scraping assembly for automatic removal of solids

摘要

A centrifugal separator includes a rotatable separator bowl, a hollow shaft spindle in the bowl along the rotational axis of the bowl, and a variable-drive motor for selectively rotating the bowl at a high separating speed and at a lower scraping speed. A scraper and feed assembly including scraper blades is supported by the shaft spindle within the separator bowl. A feed liquid is supplied to the separator bowl via the scraper and feed assembly at substantially the interior surface of the separator bowl. The scraper assembly rotates with the bowl at the separating speed while centrate is drawn off. While the bowl is operated at the scraping speed, the scraper assembly is prevented from rotating with the bowl and is moved axially with respect to the bowl to scrape accumulated solids from the interior surface of the bowl. Loosened solids exit the centrifuge via a discharge port at the bottom of the bowl.