15 High Rate Mixing Pump Shutdown
Typically, the High Rate Mixing Pumps run in automatic mode, 24 hours per day, seven days per week.
To shut down the pump(s) for repair or maintenance.
Watch for open tanks and high elevations. If working on or near equipment, watch for rotating parts. Watch for tripping hazards and overhead piping while manipulating the valves.
Use caution when rotating valves. Valves must be opened and closed in a particular order. The first step should always be to open a valve. If the operator’s first step is to close a valve, there is a risk that two valves on that pressure system may be closed. If this happens, pressure sensors should signal an alarm. The worst case scenario is that the high pressure created in the closed pressure system would cause damage and/or failure of the system. Warning: always verify which valves are open and closed before making any changes.
Operator I, knowledge of digestion process and equipment controls.
- Key or other tool to open/close valves.
- Record activity to log book.
1. Turn off pump control at the control panel. The High Rate Mixing Pump controls are located on MCC-5 in the Digester Control Building.
a. Locate the Control Bucket {tag nos. 1505BKT5100 & 1505BKT5200} for the pump(s) to be stopped.
b. Turn the On/Off Switch {tag no. 1505HS5100B & 1505HS5200B} to the OFF position. The green indicator light should go out when the pump stops running.
c. Place the Main Breaker {tag nos. 1505BKR5100 & 1505BKR5200} in the OFF position.
2. Turn of f pump(s) at the local control switch.
a. Each High Rate Mixing Pump is equipped with a push button Lock Out Switch (LOS) {tag nos. 1505HS5100A & 1505HS5200A} and a Disconnect Switch {tag nos. 1505HS5100 & 1505HS5200}. Both switches are installed to a stantion, located adjacent to the pump.
b. Turn the Disconnect Switch {tag nos. 1505HS5100 & 1505HS5200} to the OFF position.
c. Place the Lock Out Switch {tag nos. 1505HS5100A & 1505HS5200A} in the “Stop” position by pushing the plunger in.
d. Follow the Lock Out/Tag Out procedure for the pump. Click here for a copy of the procedure.
3. Verify Suction and Discharge Valve Status.
a. Each High Rate Mixing Pump system is equipped with two isolation suction valves: a bottom suction valve {tag no. 1505VLV5100 & 1505VLV5200) and a top suction valve {tag no. 1505VLV5100A & 1505VLV5200A}. Locate the suction valve that is currently open and close that valve. Both isolation suction valves should now be closed.
b. Each High Rate Mixing Pump is equipped with one isolation discharge valve {tag nos. 1505VLV5100F & 1505VLV5200F}. Close the isolation discharge valve.
4. Observe High Rate Mixing Pump Operation:
a. Listen for excessive noise or vibration.
b. Check for oil or process fluid leaks.
5. Record Data to Operator’s Log Book: Record High Rate Mixing Pump Activities to the log book with other entries for the day. Include the following in the entry:
· Operator(s) that performed the High Rate Mixing Pump SOP.
· Note condition of equipment, piping, valves, etc.
· Note any unusual conditions with flows, levels, odors or other process issues.
· Note any damage, wear, or required maintenance on equipment.
- Update log book.
- Update maintenance records (if applicable).
- Report any maintenance or attention that is required.
The pumps run constantly.
EQUIPMENT NAME | TAG NUMBER |
High Rate Mixing Pump No. 1 | 1505PMP5100 |
High Rate Mixing Pump No. 1 Motor | 1505MTR5100 |
High Rate Mixing Pump No. 1 – Bottom Isolation Valve | 1505VLV5100 |
High Rate Mixing Pump No. 1 – Top Isolation Valve | 1505VLV5100A |
High Rate Mixing Pump No. 1 – Isolation Discharge Valve | 1505VLV5100F |
High Rate Mixing Pump No. 1- Suction Pressure Gauge | 1505PI5100 |
High Rate Mixing Pump No. 1 - Disconnect Switch | 1505HS5100 |
High Rate Mixing Pump No. 1 – Lock Out Switch | 1505HS5100A |
High Rate Mixing Pump No. 1 – Control Bucket | 1505BKT5100 |
High Rate Mixing Pump No. 1 – Main Breaker | 1505BKR5100 |
High Rate Mixing Pump No. 1 – On/Off Switch | 1505HS5100B |
High Rate Mixing Pump No. 1 – Indicator Light | 1505HS5100C |
High Rate Mixing Pump No. 2 | 1505PMP5200 |
High Rate Mixing Pump No. 2 Motor | 1505MTR5200 |
High Rate Mixing Pump No. 2 – Bottom Isolation Valve | 1505VLV5200 |
High Rate Mixing Pump No. 2 – Top Isolation Valve | 1505VLV5200A |
High Rate Mixing Pump No. 2 – Isolation Discharge Valve | 1505VLV5200F |
High Rate Mixing Pump No. 2- Suction Pressure Gauge | 1505PI5200 |
High Rate Mixing Pump No. 2 - Disconnect Switch | 1505HS5200 |
High Rate Mixing Pump No. 2 – Lock Out Switch | 1505HS5200A |
High Rate Mixing Pump No. 2 – Control Bucket | 1505BKT5200 |
High Rate Mixing Pump No. 2 – Main Breaker | 1505BKR5200 |
High Rate Mixing Pump No. 2 – On/Off Switch | 1505HS5200B |
High Rate Mixing Pump No. 2 – Indicator Light | 1505HS5200C |