Expeller pressing

When used for the extraction of food oils, typical raw materials are nuts, seeds and algae, which are supplied to the press in a continuous feed.

Some other materials used with an expeller press include meat by-products, synthetic rubber and animal feeds.

[1] Some companies claim that they use a cooling apparatus to reduce this temperature to protect certain properties of the oils being extracted.

In most small-scale rural situations this is of little importance, as the remaining cake after oil extraction finds uses in local dishes, in the manufacture of secondary products, or in animal feed.

He wrote that "brewers' slops, slaughterhouse refuse" and other "soft and mushy" materials dewater poorly in continuous screw presses.

It was much like having a hanger bearing in a screw conveyor: there is no flighting on the shaft at that point, so material tends to stop moving and pile up.

Fitted into the gaps where there is no flighting, these teeth increase the agitation within the press, further diminishing co-rotation tendencies.

The economic advantages of these characteristics led to interrupted screw presses being used to dewater fibrous materials that are neither slippery nor slimy.