Dewatering screens after product washing
After a washing stage the product arrives mixed with water. A dewatering screen separates the two and sends the product on; the water is collected underneath.
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Where the dewatering screen sits
In a dried-fruit washing line the product leaves the washer as a mixture of fruit and water. The next stage, whether that is sorting, drying or packing, needs the fruit without the free water. The dewatering screen is placed directly after the washer for this reason.
How the separation happens
The mixture lands on a stainless steel screen surface that is vibrated by two vibration motors. Water drains through the openings while the fruit, which is larger than the openings, is carried forward along the deck and discharged at the end. The screen opening is chosen for the product group; a mesh for raisins differs from a mesh for apricots.
The collection tray and the drain
Water that passes the screen falls into a tray under the deck. The tray is not only a gutter: it also holds back larger particles and debris that would otherwise go straight to the drain. This lowers the risk of a blocked drain line, which is a common stoppage in washing areas.
Fan-assisted drying
A fan-assisted version adds an air stream over the deck after the water has drained. The air removes the surface water that remains on the fruit faster than the plain version does. This is used where the next stage is sensitive to wet product, for example dates going to a packing line.
Cleaning
Because the machine handles wet product, it is built so the screen and tray can be removed and washed. Stainless steel (AISI 304, with AISI 316 as an option where the process requires it) is used for the frame and all product-contact surfaces.
The screens described here are built by a manufacturer of stainless steel food-processing machinery in Turkey; see the contact page for the reference.