Ash slurry Operation

Pre-requistes:

  • Ash slurry pit level of corresponding ash slurry p/p is at above low level 3.0 metres.
  • BAHP and BALP pumps are running condition depending on the ash water requirement.
  • BALP or FAHP water is available for ash slurry pit make up in case level goes low.
  • Also the level transmitters and electrical operated make up valves are available to take care of the level.
  • At least one HPSW and LPSW pump must be available.
  • At least one Cooling water p/p and one CT fan is available at ash slurry pump house end or any alternate source ex. Service water or SG ECW water for hydraulic coupling cooling water requirement.
  • Instrument air available for suction/ discharge valve operation.
  • Ash slurry swgr-A&B for the ash slurry pump to be run is charged

Line up for starting the pump
  • Start any one of HPSW & LPSW pumps after suction valve opening . Gradually open the discharge valve to full, this will charge the seal water supply header for all the pumps.
  • Charge seal water to pump gland by opening the solenoid valves , if solenoid valve is not working, seal water can be supplied by opening manual bypass valve of above valves.
  • Open isolating valves in cooling water lines for hydraulic cooler. Cooling water pr must be adequate. 
  • Check that Oil level for hydraulic coupling scoop tube and the gear box oil is O.K.
  • Make hydraulic coupling scoop tube position to minimum.
  • Open the suction valve and ensured from the Local.
  • Start the F/C pump
  • Select normal mode out of normal / flush tab
  • Check that seal water pressure for the 1st ,2nd and 3rd pump in series as abov 4.2ksc , 8.4ksc & 12.6 ksc respectively .Start the 1st ash slurry pump
  • The pneumatically/motorized operated discharge valve of the pump opens on auto
  • Now position of the scoop can be increased and locked at any % as per requirement.
  • Start the second and Third pump in the same way.
Line up for flushing the pump
  • keeping rest of line same as required for running ,close the suction valve an open flushing line manual valve v/v
  • Select flush mode out of normal / flush tab
  • Check that seal water pressure for the 1st ,2nd and 3rd pump in series as above 4.2ksc , 8.4ksc& 12.6 ksc respectively .Start the 1st ash slurry pump.
  •  Start the flushing pump. 
  • Start the 1st ash slurry pump.
  • The pneumatically/ motorised operated discharge valve of the pump opens on auto.
  • Now position of the scoop can be increased and locked at any % as per requirement.
  • Start the second pump in the same way.

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