Tummers Food Processing Solutions introduces a new mobile washing installation for potatoes. Dustin-Dwight Verhagen, responsible for marketing, and Sales Engineer Robert Quaak, discuss the ins and outs of this new machine.
The new installation is a combined machine, in which separation of stones and earth precedes washing of the potatoes. The machine has a washing capacity of 40 tonnes, but that’s dependent on the product type and the state of the product to be washed. Washing a batch of potatoes at 30 tonnes an hour is no problem for this machine.
Left to right: Harold Siderius, Dustin-Dwight Verhagen, Robert Quaak
Looking at the fully stainless steel machine from up close, the process starts with the separation of earth, stones and other heavy parts. In a bath, through upward force, the potatoes are forced to the water surface, and through the flow the potatoes will go farther into the process, i.e. washing in the drum. The earth and stones will fall to the bottom, where a barred belt will catch them and transport them to the back. The propeller causing the upward force can be adjusted for more intense or softer force, depending on what the product flow at the time requires.
99% stones and earth removed
After these actions, 99% of the stones and earth are removed, and the potatoes enter the washing drum. The six corners, together with the drum’s blades, cause a “wave effect”. This effect creates friction on the potatoes, causing them to wash themselves, in combination with the water. A specific feature of the drum is that the guiding wheels and the belts are mounted above the water level. An advantage of this is that less wear and tear arises, causing less maintenance.
In order to regulate the washing intensity, the end of the washing drum has a dosage dial with which the washing intensity can be regulated. The higher the dosage dial, the longer and more intensively the potatoes are washed.
With the potatoes reaching the end of the machine, they end up in a bath, where paddles remove the last foreign parts, such as foliage and corn cobs. This optional system on the combination machine is called the “floating parts separator”. The potatoes are then transported on a belt underneath a spraying tube, for a final spraying.
Roller dryer
With the product clean, it also needs to be dried. The potatoes go through a roller dryer, with the first roll made of rubber to gently catch the potatoes, causing an even spread on the roller bed. The subsequent rollers are covered with felt: this ensures liquid is absorbed, and possible small defects, such as sprouts on the potato, remain behind. Below the felt rolls are the pressure rollers, pressing the felt rolls dry. Debris and water is caught in a drip tray, where continuously flowing water drains it away.
Now the product is dry, it ends up on a belt where the bad potatoes can be removed. The result is a clean end product that, after passing a fall damper, is transported to its destination.
Below the machine there are spray valves, ensuring automatic flushing of the used water. The frequency of flushing depends on the product to be washed: dirty, very dirty, a lot of or little sand, etc. This can be adjusted with pre-programmed washing programmes or manual settings. The used water then goes into the settling tank, which filters the water so it can be reused. The machine also has a power generator, so the machine can be used anywhere. For countries like England, where the distances from the fields to storage or factories can be large and very remote, this machine is ideal.