The raw potatoes come via a belt conveyor into the rod de-soiler of the washing plant. The potatoes then arrive into the cyclone-destoner, where an upward stream makes the potatoes float, while heavy parts such as stones and clods sink. A special stone conveyor seizes these separated heavy parts, lifts them out of the water and drops them in a container.
It is used to peel the fresh potato by steam
Pre-cooking and cooling
An inspection belt conveyor transfers and feeds the peeled potatoes through a distributor into the slicing machines. Here the potatoes are cut into slices to allow definition of heat transfer during the pre-cooking process.
The thickness of the cut can be adjusted.
Then the potatoes are pre-cooked in a warm water bath. The pre-cooker is of a steam injection screw type.
The product is discharged from the wet hopper via a water lock and transferred hydraulically. A vibrating screen separates the potato slices from the conveying water, which flows back through an equalization tank into the hopper. A balance provided in the downstream belt conveyor measures the mass flow rate, which is set by varying the speed of the product feeder.
From the screw type cooker the cooked potatoes drop down directly into the mashing screw conveyor, which gently pushes them through a perforated template for mashing. Additives are added and mixed with the mash in a downstream screw conveyor, which feeds it to the drying plant.
A single drum drier is employed to dry the mash.
The unit comprises an internal steam heated drying drum, six non-heated surface treated applicator rolls and the necessary bearings. A common chain drives all the applicator rolls. A frequency converter allows the speed, and consequently,
Pre-breaking and conveyance
The layer formed on the drum drier comes off like a web of paper, which a special screw conveyor collects, tears and feeds to a pre-breaker attached at its end.