Spray Dryer Standard Operating Procedure

Transcription

1 Spray Dryer Standard Operating Procedure Created: October 19, 2010 by Bob Cox Revised: January 11, 2012 by Bob Cox University of Utah, Chemical Engineering This document outlines the operating procedures for the spray dryer located in room 3520 MEB. Overview: Prior to operating the Bowen Spray Dryer familiarize yourself with the plumbing, display gauges, control panel, pump, pump drive, and blower. The Bowen Engineering Spray Dryer is a pilot scale device commonly used for drying thermally sensitive materials. In the Senior Lab, it has been used for drying a variety of solutions including soap, salt and beer. Verify that any solution pumped through the system will not clog the lines or the spray nozzle. Check with lab manager before preparing a new solution. Health & Safety Warnings Safety glasses must be worn when operating this equipment. The manual gas control valve must be closed after each run. Do not remove the drive shaft guard. To prevent overheating, the gas burner will not light until the blower is powered on. Use caution when opening the spray dryer door during operation as liquid may escape the drying chamber. Caution exterior surfaces may be hot! Rotating equipment hazard: Use caution when in close proximity to the pump.

2 Procedure: 1. Mix feed solution in tank(s) located behind the spray dryer. Verify that the feed tank valves remain closed until you are ready to run. 2. Set (open) valves on feed tanks to feed stock solution to pump as desired. 3. Open pump petcock valve until feed stock flows out of valve, then close the valve. 4. If feedstock does not flow out of the pump valve, contact the lab manager. 5. Open the main gas pipe valve ½ turn so that the valve headpiece is in line with the pipe. The valve is located on the rear of the spray dryer. 6. Turn on the Omega HH509R thermometer located on the front of the spray dryer. 7. Open the main air supply valve located on the right side of the dryer ½ - 1 turn. 8. Set the air pressure regulation to 10 PSI. The air pressure regulator is located on the lower front panel. You may adjust the air pressure as required as you finetune your operating parameters. The airflow rate may be adjusted using the needle valve on the airflow rotometer. The units are SCFH 9. Open the liquid flow valve located on the base of the liquid flow rotometer on the front of the dryer. 10. Turn on the main power switch located on the upper left of the control panel. 11. Verify that the Baldor Drive Controller (VS1MD) displays Verify that the FWR and STP/FLT indicator lights are on and that the PROG and RUN lights are off. 13. If the PROG light is on do not proceed, contact the lab manager. 14. Note that when adjusting the speed setting on the VS1MD, you must push firmly and hold the increment / decrement arrow buttons in order for the setting to change. 15. Firmly press and hold the down arrow on the VS1MD, if the numbers on the display start to decrease hold the down arrow until the display reads If the display reads 0.00 when the down arrow is held down, proceed to the next step.

3 Check the chamber: 1. Open the chamber door. The chamber light switch is located on the right side of the control panel. Verify there are no obstructions in the chamber. If the chamber requires cleaning, use the hose located behind the spray dryer to clean the system. Cleaning supplies are located in the stock room. It is your responsibility to clean the spray dryer after each use. 2. Verify that the spray nozzle is connected to the air and feed lines. 3. Close the chamber door. 4. Latch both chamber door fasteners to secure the door. Set pump speed: 1. Verify that the flow control valve on the flow rotometer is rotated all the way to the left, open 100%. 2. Press and hold the up arrow button on the VS1MD, the display will increment, continue to hold the up button until the display reads ~ 20.00; this is a good starting value for the pump speed. A set point of 20 corresponds to a flow of approximately 2 GPH. 3. Depending on the feed solution, a set point of approximately 20 is required to establish a fairly stable flow. 4. The flow rate is in GPH as displayed on the small rotometer. 5. It is recommended to use the pump speed to control flow. Not the rotometer flow valve. 6. The pump speed may be adjusted at any time during operation my firmly holding down the up / down arrows on the VS1MD. 7. The maximum pump speed is the minimum speed set point is Note that the pump drive will not rotate if the set point is below approximately Press the start button on the VS1MD to start the pump. Stopping the pump: To stop the pump push the red STOP / RESET button located on the upper right of the VS1MD.

4 Restarting the pump: Pushing the red START button on the VS1MD will immediately start the pump at the last set point. To display the set point currently in the controller memory, press the up/down arrow button before pressing the start button. If you wish to start the pump at a speed other than the last set point use the up/down button to set the desired set point prior to pushing the start button. Start the blower: Push the black start button on the fan control panel; you should immediately hear the blower power up. Setting the burner temperature: The Partlow burner temperature adjustment is located on the rear of the spray dryer, to the right of the main gas valve. The temperature may be adjusted at any time during operation. Lighting the burner: Note - the blower must be running in order to ignite the burner. Verify that the main gas valve is open. Push the black start button (burner control) located directly above the fan start/stop control. Verify that the burner is lit via the observation port on the burner assembly.

5 Sample Collection: Sample material is collected in the bell jar located at the bottom right of the spray dryer. Additional bell jars and spray nozzles are located in the workbench in front of the spray dryer. Shutdown: Stop the pump Turn off the burner Turn off the blower Turn off the main power switch Turn off the Omega HH509R Close the main gas valve. Close the feed valves (ball valves) that control the feed flow from the feed tanks to the pump. Drain & rinse the feed tanks as needed. Rinse the spray dryer chamber. Clean the work area. If you plan on leaving feed solution in the tanks overnight, it must be labeled.