Installed situations of the sugar centrifugals
Dissolved sugar discharge
For dissolving sugar, the Konti 12 offers two variations as follows:
- First the conventional method, exemplified by means of a traditional centrifugal for dry sugar discharge with additional dissolving equipment, consisting of a ring pipe (11) and impact ring (12). The dissolving water is supplied through the ring pipe (11). The sugar is broken on the impact ring (12) dissolved by water and flows off downwards. In this case, a hopper and a conveyor for the reception of the dissolved sugar has to be installed underneath the centrifugal.
- The second and more elegant method is the application of a dissolving centrifugal unit KONTI 12DCH. The operation of this centrifugal is approximately identical to a centrifugal for dry sugar discharge. The only difference is that a drain channel is installed in the interior of the dissolving centrifugal unit, which transports the dissolved sugar to discharge pipe (31). The solid-content (Bx) of this sugar solution can be continuously read off on a spindle. It is installed in a pipe which is connected with the discharge pipe (31). In this case it is not necessary to install a hopper and a conveyor under the centrifugal. From here the dissolved sugar can directly be conveyed for further processing without any additional treatment.
In case that dissolving sugar is required, instead of the conventional version as described under a), the Konti 12 DCH version should definitely be the preferred choice.
The centrifugal offers the possibility to mingle the sugar within chamber (14) of the centrifugal. For this purpose, the centrifugal will be equipped with mingler ring (15) and pipe (11) through which syrup will be fed onto the top ring of the basket.
A pre-mingled sugar, reaching the affination mixer in this way, does not form any lumps during the affination process (see also Fig. 1).
The centrifugal offers the possibility to install an additional inner casing (16) in order to separate mother and wash syrup from each other. The wash syrup being separated via a separate pipe (30) is of higher purity than the mother syrup being separated via pipe (25). Above the washing zone of the double wall basket a drainage ring separates mother syrup from wash syrup. A good syrup separation should have the effect that the entire mother syrup has been discharged. Only wash water with dissolved sugar and washed syrup residues should result as wash syrup. For raw sugar II we use 4 % wash water on massecuite. Therefore the ratio between mother and wash syrup would have to be approx. 10:1. Is it lower, mother syrup enters the wash syrup and the difference of purity between both syrups becomes small. The mother syrup is centrifuged in the lowest screen area. The wash water area with several wash water nozzles washing the sugar and the drying area in the upper area of the basket are to be followed. Here it is possible to feed wash water or thin juice via flat jet nozzles to the upper area and thick juice via one flat jet nozzles to the lower area of basket. (also refer to washing with additional thick juice)
From experience, the separation of mother and wash syrup must be located in the upper area of the washing area. The separation area where mother syrup runs off, depends on the quantity of incoming massecuite. If a huge amount of massecuite is applied, this separation area is expanded upwards and more mother syrup enters the wash syrup. The more the capacity of the raw sugar centrifugal is utilized, the more the difference in purity between both syrups is reduced. A low charged raw sugar centrifugal has a huge amount of purity difference.
Washing with additional thick juice
Washing with thick juice in raw sugar II with a Konti 12 centrifugal.
By feeding thick juice and single curing centrifuging a colour reduction of 94 % has been achieved with a Konti 12 centrifugal.
|Massecuite colour:||9330 IU 420|
|Dissolved sugar colour:||550 IU 420|
|Quantity of thin juice:||650 l/h|
|Quantity of thick juice:||85 l/h|
|Feeding capacity:||18 t/h|