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Puridest Glass Distillation Apparatus
09/2020
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Functional Description
Puridest Glass Distillation Apparatus
LAUDA Puridest Glass Distillation Apparatus models PD 2 G, PD 4 G, PD 8 G, PD 2 DG and PD 4 DG work fully
automatically. After switching on the Distillation Apparatus on the main switch, both the green pilot lamp in the main switch
and the pilot lamp "Low water" will light up. The built-in solenoid valve opens and water flows through the cooling coil of the
condenser into the boiler. Water fills the boiler until the heating element is below water level. The water level is controlled by
a float switch that starts the heating element. At the same time, the pilot lamp "Low water" is switched off. After a short
time, the water in the boiler comes to the boil, steam rises into the glass condenser and condenses on the cooling coil.
In Mono Glass Distillation Apparatus (models PD 2 G, PD 4 G and PD 8 G) distilled water can now be withdrawn from the
distillate outlet.
In Bi Glass Distillation Apparatus (models PD 2 DG and PD 4 DG) the distillate produced in the mono stage is used to fill
the boiler of the bi stage until the heating element in this stage is below water level, too. In the second distillation stage,
another float switch controls the water level in the boiler and starts the heating elements. Once the water boils in the second
stage, and steam condenses on the cooling coil, bi distillate can be withdrawn from the distillate outlet of Bi Glass Distillation
Apparatus.
Protection against over-heating in case of low water
Float switches control the water level in the boilers. Power to the heating elements is cut off before the heating elements
are not below water level any more. The pilot lamp "Low water" will light up. In the event that the float switches do not cut
off power in case of low water, the temperature in the boilers is additionally controlled by thermostatic low water cut-offs.
The low water cut-offs switch off power once the temperature in the boiler exceeds 135 °C. Only the pilot lamp in the main
switch will remain on.
Glass Distillation Apparatus with separate water supply
Only factory installation is possible.
The accessory "separate water supply" serves to feed the boiler with softened or desalinated water, and the cooling coil with
phosphatized or normal tap water. The quantity of inflowing process water is controlled by a float switch and a solenoid valve.
The amount of inflowing water is limited to the amount of water evaporated
Owing to the separation of cooling and tap water, the water fed to the boiler is not pre-heated, the efficiency of the still is
therefore reduced by approx. 10-15 %.
Glass Distillation Apparatus with level control switch for external storage tank
A float switch, mounted to a plastic tube, is to be led into a storage vessel (to be provided by the users, not available from
us). When the storage vessel is full, power and water supply to the Distillation Apparatus are cut off by the level control
switch through the unit's electronic control.