Single and Two-phase Flow in a Packed Bed Reactor

1. Starting up the apparatus

The apparatus is primarily operated through the distributed control system interface. A Perm P&ID schematic appears and opening/closing automated valves is point and click.

1. To establish water flow to either bed #4 or #5, open the inlet and exit valves to the bed being tested and the water supply solenoid.
2. Use the flow controller to start water flowing through the bed, raising it gradually. Good starting points are 400 mL/min for bed #4 and 500 mL/min for bed #5. Monitor the differential pressure across the beds. Vary the flow to cover the entire possible range of the DP transmitter.
3. Power up the spectrometer equipment and establish communication with the control console. Spectrometer procedures are detailed in the operating manual (SpectraSuite). The calibration of the spectrometer for the fluorescent dye standards will be provided.
4. Perform one tracer test each on beds #4 and 5 using 50 ppm dye in DI water as the tracer, at a single average flow rate for each bed.
5. Insert the spectrometer probe into the probe sample point (Fig. 1). At the PERM interface, change injection valve status from "Running" to "Charging."
6. Inject the tracer using the syringe provided into the sample valve. Change the status to "Running".
7. Clean out the injection chamber of the sample valve by changing its status back to "Charging", detaching and loading the syringe with water, then injecting at least 100 mL of water into the valve. When the injected sample has completely exited the bed (spectrometer absorbance returns to base line), change the valve state back to "Running" and let the water flow through the valve for 10 - 15 min at a high flow rate before using it again.

2. Conducting Two-Phase Flow Pressure Drop Experiments

Be sure that the water valves to the beds are closed, the inlet and exit valves to bed #5 are open, the drain valve is open, and that the manual valve for the air to the beds is closed.

1. Slowly open the air regulator to establish an air flow (< 5 psig at first). Open the manual valve for the air to the beds.
2. Set water flow controller at desired setpoint (700 mL/min) and open manual valve. Route water/air flow to gas-liquid separator (see valving in Fig. 1).
3. Confirm that water is exiting to drain. Close the valve to the drain for a period of time to build up a liquid head in the gas-liquid separator. This will result in better separation of the air and water.
4. Adjust air flow (typically < 2 SCFM) as desired using the pressure regulator and the dry test meter on the gas exit line. Close the drain valve for short periods of time to get a correct gas flow reading on the wet test meter.
5. Conduct two-phase flow pressure drop (use DP transmitter) experiments using bed #5, at multiple air rates. Try to cover the range of the DP transmitter. Disconnect the dry test meter if you see water exiting from the gas exit line.