Standard Operating Instructions

Startup, Shutdown and Malfunction Plan

Startup

1. Record the gas meter reading before starting the furnace.
2. Visually inspect furnace for any broken equipment or items in need of repair.
3. Turn furnace primary holding and afterburners on.
4. Allow for afterburner temperature to reach 1600° F.
5. Begin loading scrap aluminum in the primary chamber, not exceeding permit limits.

Shutdown

1. After molten aluminum is poured into molds for the day, turn off furnaces for the primary, holding and afterburners.
2. Record the gas meter reading after turning off furnace.
3. After primary chamber has cooled, remove all none aluminum metals.
4. Weigh, number and record all molds poured.

Complete Operating Instructions (SOP)

Turn power and main gas valves on and record the gas meter reading.
Raise all doors and inspect all chambers.

1. Start combustion blowers. Start “Primary 1”, “Primary 2” “Holding chamber 1”, “Holding chamber 2” and “Afterburner burners” by turning the selector switches to the on position. Observe that each burner did in fact ignite by observing burner on lights and physically observing the flame by site.
2. Close all doors.
3. Prepare work area for production day.
4. Install the afterburner data logger.
5. Select material to be charged and load on the table. Note: Refer to “Items not to be charged into the chamber” as described by the permit, i.e. magnesium, cadmium, radioactive, PCB’s, PVC’s, etc. materials.
6. When the afterburner temperature has reached at least 1600 deg. F and the primary and holding chamber have reached the desired set point the furnace may be charged.
7. The afterburner temperature is recorded as 15-minute block averages and also 3-hour block averages by a data logger.
8. Turn the “Hi – Low Fire” switch to low. Raise the primary charge door and push material into the chamber.
9. Close the door and observe the temperature controls. Note: Specifically observe that the afterburner chamber did not drop below 1600 deg. F. If said chamber does drop below the required temperature, the set point will need to be raised to prevent a violation during the time the door is open. The standard set point is 1650 deg. F to prevent a violation.
10. Record the charge time, material type, afterburner temperature and the size of the load in the “Daily Operators Log”.
11. Turn the “Hi-Low Fire” switch to high after most of the combustible material has burned off. Stir and rake the material as required by the material being processed. Average stir time is 10 to 15 minutes after charging the load. An additional stir and preliminary rake is usually required within 5 to 10 minutes. Average final rake out time is 25 to 40 minutes after charging. Record all stir and rake times on the “Daily Operators Log”.
12. Observe temperature controls throughout the operating day to assure proper operation of all chambers.
13. Observe the exit of the stack for emissions after each charge and make the proper adjustments to the draft controls if necessary.
14. Drain the holding chamber as necessary. Note: Follow all required safety procedures during the draining of the holding chamber.
15. When process day is complete, turn off all burners and leave the combustion fans on until the temperature has dropped below 500 deg. F.
16. Turn off the main gas valve.
17. Clean all chambers thoroughly.
18. Record the weight of material processed on the daily log sheet.

Possible Malfunctions and Corrective Actions

For all malfunctions:

Record the date and time the malfunction began and ended in the Malfunction Log.
Record the corrective actions taken including the date and time the corrective action(s) began and when it was completed.

1. Burner will not light or stay lit and or chamber will not reach set-point temperature:
a) Check that combustion blower is on and the airflow switch has closed to allow line voltage to the flame safety device. If blower is not operating check fuses or circuit breakers. If voltage is supplied to the motor and still does not work, replace the motor.
b) Check flame safety relays for proper operation and replace if necessary.
c) Check flame rod for proper operation and clean or replace if necessary.
d) Check ignition electrode for proper operation and clean or replace if necessary.
e) Check reset button on flame safety device for proper operation.
f) Check that the proper gas supply is present and all valves are open.

2. Control does not display the temperature:
a) Check fuse and power to the control.
b) If there is power at the control and still no temperature readout, perform the following test: Remove “positive” and “negative” thermocouple leads from the back of the control. Install a jumper wire between the terminals that the wire was removed from. Observe the digital display for an ambient temperature display. If the display is present refer to item c.
c) Remove temperature probe and remove the element from the probe housing. Inspect the element for signs of damage or breaks. Check housing for pitting or burnout. Replace damaged items if necessary.
d) If there is still no temperature display after following items a, b, & c instructions, replace and program a new temperature control.
e) Do not operate the sweat furnace until the new data logger is installed and operational.

3. Data logger did not record temperatures properly or no readings whatsoever.
a) Observe the afterburner control temperature readout. If no digital display is present, follow the instruction for problem number 2. Note that the afterburner temperature probe has a double element, one for the control and one for the data logger.
b) Check all connections from the probe to the data logger.
c) Refer to the “Daily Operations Log” to see that furnace was operating during the temperature recording period.
d) Check that the data logger was “Started” when connected to the computer using the Omni Log software management program.
e) Check logger while connected to the computer for proper temperature range and type (as in C or F).
f) Check internal battery power while connected to the computer.
g) Program and install. Run the logger for a two hour test. Remove logger and download information to check for proper operation. Reinstall logger.
h) Program and install the backup logger if necessary.

4. Visible emissions are present out of the stack.
a) Turn “Hi-Low” switch to the low position.
b) Turn the primary burners to the off position if smoke is still present.
c) Open the afterburner draft door to a 4” opening. Note: Close the afterburner draft door when combustible material is not present to prevent over cooling of the afterburner.
d) Check material to find the source of excessive emissions and remove from all future charges.
e) Record the time and duration of excessive emissions in the “Daily Operators Log”.
f) Note and record the afterburner temperature in said log.

5. Data logger records values less than 1600°F.
a) Noticed by the operator reading the digital temperature at the controller.
b) Could occur due to a blown fuse in the burner or low air flow in the burner.
c) Follow the corrective actions under item 1 above.
d) Record the corrective action taken to bring the temperature back up to 1600°F.
e) Record the date and time the corrective action began and the time it was completed on the Malfunction Log.

6. If the malfunction is not identified here, modify this report within 45 days of the malfunction to include it and the corrective actions.
a) If emissions standard was exceeded, report the malfunction within 2 days to the proper air quality control agency.
b) Submit a letter within 7 working days explaining the circumstances of the event, the reasons for not following this plan and whether or not any excess emissions and/or parameter monitoring exceedances have occurred.

Emergency Shutdown (in the event of interrupted gas supply, gas leak, or power outage)

1. Turn off main electrical supply and gas supply and empty the molten aluminum.
2. Contact supervisor.
3. Supervisor is to contact the appropriate utility for leak checks or explanation of interrupted service.
4. Keep records of service interruptions and make notes on data logger spreadsheets should the afterburner temperature drop prior to the batch process completion