Tray Dryer – Operation And Cleaning Guide

Most tray dryers used in the pharmaceutical industry comprise a heated cabinet in which a rack of trays is located. They are frequently used for the drying of granulated powder. Heat can be provided by burning a fuel, e.g. natural gas or, more usually, by one or more electric elements located within the cabinet, together with a blower to circulate the air. Semi-automatic tray dryers are also manufactured for drying large quantities of materials. These are, however, typically used for the production of dried fruit and vegetables, and include a mechanism by which the lowest tray in the drying cabinet can be removed (once the material on the tray is dry), thus allowing the higher trays to be lowered. In all cases of tray dryer, the basic method of operation and procedure for cleaning the machine is the same.

Operation

1. Before starting the dryer, check that the machine is clean.
2. Check that the main switch is off.
3. Load the materials that need to be dried onto the trays and close the door firmly.
4. Set the temperature as per the BMR and turn on the electrical supply.
5. Start the blower and heater.
6. Run the dryer for the prescribed length of time to achieve the required degree of drying.

Cleaning

1. Switch the tray dryer switch off.
2. Remove the “under use” label and attach a “to be cleaned” label.
3. Use a dry duster to remove the dust on the body of the dryer cabinet.
4. Remove all the trays inside and place these in the washing area.
5. Ensure that all of the dried material has been removed.
6. Clean each tray with potable water then use a nylon scrubber and clean with a suitable surfactant e.g. , 0.1% Teepol solution.
7. Clean each tray with 5 litres of potable water followed by 3 litres of purified water.
8. Remove the water using a compressed air blower.
9. Dry all trays with a lint free dry cloth.