S11.1 Closed Cooling Water

7/28/2019 S11.1 Closed Cooling Water

1/8

GL1.Z COMPLEX - SONATRACH

PROCESS OPERATING MANUAL

CLOSED COOLING WATER

SECTION No 11.1~ REVISION No. 2

GL1.Z RENOVATION PROJECT


2/8

TABLE OF CONTENTS

1.0 GENERAL OVERVIEW...........................................................................................1

2.0 OPERATING PRINCIPLES....................................................................................1

2.1 Process Description...............................................................................................1

3.0 PREPARATION FOR START-UP...........................................................................2

3.1 Filling the System..................................................................................................2

4.0 NORMAL START-UP...............................................................................................2

5.0 NORMAL OPERATION...........................................................................................3

5.1 Normal Operating Parameters..............................................................................3

6.0 PROCESS CONTROL..............................................................................................3

7.0 NORMAL SHUTDOWN...........................................................................................4

8.0 PROTECTIVE SYSTEMS AND EMERGENCY SHUTDOWN.............................4

8.1 Primary Protection................................................................................................4

10.0 TROUBLESHOOTING..........................................................................................4

11.0 APPENDICES.........................................................................................................6

11.1 DCS Print-outs....................................................................................................6

11.2 Process Flow Diagrams - PFD's.........................................................................6

11.3 Process and Instrument Diagrams P&ID's......................................................6

11.4 Cause and Effect Charts......................................................................................6


3/8

Aug 2001 Page 5 of 5Rev 2SECTION 11.1

PROCESS OPERATING

MANUALCLOSED COOLING WATER

1.0 GENERAL OVERVIEW

The closed cooling water system is installed to provide the cooling system

for the Turbine Seal gland condensers, Turbine Ejectors, the Process

Boiler areas and the Mitsubishi 400 T/hour boiler auxiliary equipment.

The cooling water is distilled water with corrosion inhibitor added.

Alternatively, potable water can be used as a makeup supply.

2.0 OPERATING PRINCIPLES

2.1 Process Description

The closed cooling water systems are located in Units 200/400/600. Each

system supplies 2 Process units and may supply the Mitsubishi 400T/hour boilers via a common header. Normal operation has only one unit

supplying the Mitsubishi boiler. Two electric motor driven pumps are

supplied for each system. Normal operation has one in service with the

other in "Auto" standby. Water exits the discharge of pumps, X20-J-

370/371 and flows to "plate" exchangers, X20-E-334/335 where it is

cooled by seawater from the process seawater supply system. The closed

cooling water system supplies the following users:

Forced draft Fan turbines (Process boilers) 7X0-D301K1T, 7X0-

D302K1T, 7X0-D303K1T bearings and Lubrication oil coolers.

Seal cooling for BFW pump 7X0-J-349.

Oil cooling for BFW pumps and turbine 7X0-J-349/369

Sample coolers for 7X0-D301/302/303

Bearing cooling for X02-K01.30R-JT1

Bearing cooling for X01-J-503 MEA pump.

Bearing cooling for X04-J-07.95 C3 transfer pump.

Bearing cooling for X10-J-07.47 C3 return pump.

Bearing cooling for X10-J-07.37 C2 return pump.

Bearing cooling for X10-J-07.57 C4 recycle pump.

Bearing cooling for X10-J-07.61 C4 recycle pump.

Gland condenser X05-K01.20E

Ejector condenser X05-E-301







Bearing cooling for X03-K-01.10R JT1

Bearing cooling for X03-K-01.10R JT3


4/8


PROCESS OPERATING


The cooling water returns back to the pump suction lines. On the

return header a Surge drum, (X20-G-338) is provided to maintain

stable flow to the pump suction. Potable water make-up is added viaLV-X20-01 as is necessary to maintain the proper water level in the

system.

3.0 PREPARATION FOR START-UP

3.1 Filling the System

This section describes the initial cleaning and filling of the Closed cooling

water circuit after a shutdown.

Fill X20-G-338 to 80% with potable water via LV-X20-01.

Remove the suction spools on both CCW pumps, (X20-J-

370/371).

Open the suction valves on both pumps and flush the piping until

clean. Reinstall the suction spools with temporary strainers in line.

Refill X20-G-338 to 80% with potable water.

Remove the inlet spools on X20-E-334/335 downstream of the

valves.

Ensure both pumps are primed. Start either pump, (discharge

closed) and slowly open the discharge valve to flush the piping to

the cooler inlet lines. Reinstall the inlets spools when the piping is

clean.

Refill X20-G-338 to 80%.

Disconnect the inlet/outlet piping to all CCW users and install

pipe spools. Flush the lines until clean using the system pumps.

Repeat this process until all the piping is clean in all trains.

Inventory the system with distilled water. Add the proper

corrosion inhibiting chemicals, (Nalco 8539) and circulate the

system.

4.0 NORMAL START-UP

It is assumed that the system has been filled with distilled water and the

necessary chemicals added.

Set LIC-X20-01, at 60% in Automatic.

Ensure the seawater is open to one of the seawater exchangers.


5/8


PROCESS OPERATING


Start one of the CCW pumps in the "HAND" position. Place the

stand-by pump in "AUTOMATIC".

Open the supply and return valves to each piece of equipment as is

necessary for start-up.

5.0 NORMAL OPERATION

5.1 Normal Operating Parameters

Normal operation of the closed cooling water circuit has a system

supplying Units 100/200, a system supplying Units 300/400, a system

supplying Units 500/600 and one of the units supplying the 4 Mitsubishi

boilers.

The system has one pump and one heat exchanger in service with the

other pump in Automatic standby, starting by PSLL-X2014. Normal

pump discharge pressure is 4.6 Bar. Design flow from the pump discharge

is 695 m3/hr with the exchanger outlet temperature of 30 C. The cooling

water flow to the 4 Mitsubishi boilers is 320 m3/hr and the flow to each

process unit being 187.8 m3/hr. The cooling water return header design

temperature is 35 C.

6.0 PROCESS CONTROL

The closed cooling water system supplies cooling water to the varioususers in the Process units and the Mitsubishi boilers. A surge drum X20-

G-338 is provided for the pump suction and to maintain a constant level

in the system. Level indication is provided locally on gage glasses, LG-

X20-02A/B. A level transmitter, LT-X20-01 is provided which sends a

signal to LIC-X20-01, which in turn acts upon LV-X20-01 to makeup

potable water into the system. LIC-X20-01 is normally set at 50% and has

High and Low alarm functions on the DCS.

Two circulation pumps, X20-J-370/371 are provided with local hand

switches (3 position) H-O-A. Normal operation is one pump in the Hand

position, the other in Auto standby. Pump running indication is provided

on the DCS by JI-X20-18/19. Pump discharge pressure is indicated

locally by PI-X20-15 (X20-J-370) and PI-X20-16 (X20-J-371). On the

common discharge header a pressure switch, (PSLL-X20-14) is provided

which sends a signal to PALL-X20-14 that automatically starts the

standby pump on low header pressure. Pressure transmitter PT-X20-13 is

provided with DCS indication on PI-X20-13. Temperature is indicated

locally on TI-X20-12.

The cooling water flows through one of the two exchangers X20-E-

334/335 where it is cooled by seawater. Local CCW outlet temperature is

provided on TI-X20-07/08. Provisions to measure the Seawater outlet


6/8


PROCESS OPERATING


temperature are installed on each exchanger TW-X20-09/10. A local

differential pressure indicator, PDI-X20-17 is installed to measure the

differential pressure across the seawater inlet strainers for plugging.Common CCW outlet temperature is monitored by TE-X20-11 with DCS

indication and alarm functions on TI-X20-11.

7.0 NORMAL SHUTDOWN

The closed cooling water system is similar to the seawater system, as

when equipment does not require CCW it can be isolated to the

equipment. To shutdown the entire system:

Isolate the valves from the Mitsubishi boiler supply and return

header.

Stop the pumps, X20-J-337/338. De-energize the electrical supply.

Isolate LV-X20-01, potable water make-up supply.

Isolate and drain the system as is required.

8.0 PROTECTIVE SYSTEMS AND EMERGENCY SHUTDOWN

8.1 Primary Protection

TSV-X20-06, X20-E-335 thermal relief set at 6 Bar.

TSV-X20-03, X20-E-334 thermal relief set at 6 Bar.

10.0 TROUBLESHOOTING

Effect Check List Immediate Action

Low level in X20-G-

338

Check the level on the

sight glass.

Check the operation ofLIC-X20-01

Ensure there is

distilled & potable

water available from

utilities.

High cooling water

temperature on TI-

X20-11

Verify the temperature

locally.

Check seawater inlet

strainer, PDI-X20-17

Adjust the seawater

flow.

Switch exchangers,

isolate and clean the

seawater inlet strainer.

Pump discharge

pressure low, PALL-X20-14

Verify the standby

pump has started.

Ensure the pump is in

Automatic.


7/8


8/8


PROCESS OPERATING


11.0 APPENDICES

11.1 DCS Print-outs

11.2 Process Flow Diagrams - PFD's

11.3 Process and Instrument Diagrams P&ID's

85-X00-24.1

85-X00-24.2

85-X00-24.3

85-X00-24.4

85-X00-26

11.4 Cause and Effect Charts

S11.1 Closed Cooling Water

Documents

Transcript of S11.1 Closed Cooling Water