Operating Procedure: Spray Drier

Safety Precautions  Take care to follow the order described below for start-up and shut down. Equipment damage or personal injury may result.  Use caution when operating the burner. Do not leave the main gas shut-off valve open when the equipment is not in use.  Do not open the chamber door when the equipment is in operation, except when following the cleaning procedure as described below. Observation ports are provided to view the drying chamber interior.  Check the air filter before operating.

Start-up 1. Ensure the electric blower is connected to the cyclone collector with the appropriate ductwork and that an appropriate receptacle is placed below the product outlet. 2. Start the electric blower. 3. Open the main gas shut-off valve. 4. Open the pilot gas valve and light the pilot burner. 5. Adjust the Partlow temperature control to 200o F. 6. Press the burner on button and check the flame through the burner observation port. 7. When the drying chamber outlet temperature reaches approximately 180o F begin a small amount of feed. First open the air valve, and then the water feed valve (not the slurry). 8. Adjust the Partlow temperature control to an appropriate level for the process. Food and most organic materials generally require a drying temperature in the range from 300o F to 500o F. Other materials may require temperatures of up to 750o F, and a few require temperatures of up to 1000o F. Adjust the water feed rate to maintain an appropriate outlet temperature. 9. When steady state temperature is attained, switch from water feed to the slurry. Observe atomization and adjust feed air as necessary. 10. Vary burner temperature and liquid feed rate to obtain the desired product characteristics.

Shut down 1. Turn off the liquid feed. 2. Run some water through the nozzle to clean it out. 3. Turn off the water feed, and then the air feed. 4. Shut down the burner and close the main gas shut-off valve. 5. Allow the electric blower to run until the equipment has cooled off. 6. Turn of the electric blower and open the drying chamber door to inspect. If the chamber requires cleaning turn on the electric blower and brush material into the chamber outlet. If the chamber requires washing, clean with water and open the liquid drain valve to evacuate the water.