Circulating Water System

1

• Circulating Water System

This presentation is designed to provide you the
information you need to understand and operate
the Circulating Water System. You should view
all slides and read and study the information
presented. The presentation slides are advanced
by clicking on the button.
You can also advance to a selected section by
using the topic buttons..

2
In this module we will

• Describe the function of the Circulating Water
  System.
• Describe the flow paths and major components
  associated with the Circulating Water System.
• Describe the Circulating Water System process
  control loops and associated methods of control.
• Describe the steps required to prepare for and
  startup the Circulating Water System.
• Describe the steps taken during normal operation
  of the Circulating Water System.
• Describe the steps required to shut down the
  Circulating Water System.

3
Circulating Water System Function
4
The Circulating Water System Condenses Low
Pressure Turbine Exhaust Steam.
5
Cooling Tower
6
Flow Path
7
Circulating Water System Flow Path
8
Cooling Tower
9
Circulating Water System Data
10
Review Questions
Click to Review
What is the function of the Circulating Water
System?
What process is used to realease the heat from
the Circulating water in the Cooling Tower?
Click to Review
How is the Circulating Water cooled as it flows
through the Cooling Tower?
Click to Review
When you are sure you can correctly answer these
question click the Button to
continue
11
Major Components
12
Circulating Water Pumps
13
Circulating Water Pumps
14
Circulating Water Pumps Valves
15
Circulating Water Pumps Data
16
Condenser
Extraction Piping
LP Heater
Inlet Waterbox
Outlet Waterbox
Waterbox Vent
Tubes
Circ Water Inlet
Circ Water Outlet
Tube Sheet
Hotwell
17
Condenser Waterbox Valves
18
Condenser Data
19
Cooling Tower
Cells
Risers
20
Cooling Tower
21
Cooling Tower Fans
Cooling Tower Fans
Risers
Bypass
Intake Screen
22
Cooling Tower Basin
Makeup
Bypass
Screen
23
Cooling Tower Data
24
Cooling Tower Fans Data
25
Review Questions
What is the function of the Circulating Water
Pumps?
Click to Review
Which Circulating Water System Valve, when open,
allows a single Circulating Water Pump to supply
both condenser sides?
Click to Review
What component mounted in the channel between the
stop gate and the intake structure prevents
debris from entering the pump suction?
Click to Review
When you are sure you can correctly answer these
question click the Button to
continue
26
Component Controls

• Circulating Water Pump Controls
• Cooling Tower Bypass Valve Controls
• Cooling Tower Fans Automatic Controls

27
Circulating Water Pump Suction Valve Controls
B
A
A
B
28
Circulating Water Pump Discharge Valve Controls
A
B
29
Pump Cooling Water Supply
30
Circulating Water Pump Start/Stop Controls
Start/Stop Soft Keys
31
Pump Permits and Process Trips
32
Pump Lockout/Tagout
Lockout Tagout
33
Circulating Water Pump Discharge Valve Controls
34
Cooling Tower Controls
35
Cooling Tower Bypass Valve Control
Bypass Valve
36
Cooling Tower Bypass Valve Control
37
Cooling Tower Fan Controls
38
Fan Remote Start/Stop Controls
39
De-icing Control
40
Review Questions

• How is each Circulating Water Pump motor operated
  suction valve typically controlled?
• How is each Circulating Water Pump motor operated
  discharge valve typically controlled?
• How is De-icing of the Cooling Tower performed?

Click to Review
Click to Review
Click to Review
When you are sure you can correctly answer these
question click the Button to
continue
41
Process Control
42
Cooling Tower Makeup Valve Control
Makeup Valve
Basin Level
Level Controller
43

Cooling Tower Basin Level Controller
44
Auto/Manual Control
45
Basin Level Setpoint
46
Review Questions

• How is the Cooling Tower Makeup Valve actuated
  and controlled?
• What does the Cooling Tower Makeup Valve
  Controller Output Control?
• Where does the Cooling Tower Basin Level setpoint
  come from?

Click to Review
Click to Review
Click to Review
When you are sure you can correctly answer these
question click the Button to
continue
47
Circulating Water System Operation

• Startup Prerequisites
• System Startup
• Normal Operation
• System Shutdown

48
Startup Prerequisites
49
CIRCULATING WATER SYSTEM STARTUP

• Ensure Basin Level is established and maintained
• Ensure Circulating Water Pumps are ready for
  Startup
• Ensure system valves are properly aligned
• Ensure support systems are available for service.

50
Prepare the Cooling Tower
51
Establish Basin Level
Makeup Valve
Basin Level
Level Controller
52
Circulating Water Pump

• Rack in pump and valve breakers
• OPEN each pumps suction valve
• Verify motor bearing oil levels are ok.
• Valve in instrument air and cooling water.
• CLOSE the circulating water cross-tie

Circulating Water Pumps
53
Cooling Tower Fans
54
Align System Valves
Waterbox Inlet Valves
Waterbox Outlet Valves
Discharge Cross-tie Valve
Suction Valves
55
Open the Cooling Tower Bypass
56
START the A circulating water pump
M
A
57
Check Pump Data
58
A
59
Close the Cooling Tower Bypass
60
Start Cooling Tower Fans
61
At 50 Percent Load, prepare for and start the 2nd
Circ Water Pump
Cross-tie Valve
M
M
A
M
M
B
62
Re-open the Discharge Cross-tie
Cross-tie Valve
63
NORMAL OPERATION
64
Monitor Circulating Water System process
variables from DCS displays.
65
Check Cooling Tower Fans
66
De-ice Cooling Tower If Required
67
Circulating Water Pumps
68
SHUT DOWN
69
Shut Down One Circ. Pump
Cross-tie Valve
M
M
A
M
M
M
B
70
Select the Cooling Tower Fan Stop Auto Sequence
71
OPEN the Cooling Tower Bypass Valve
72
STOP the Operating Circulating Water Pump
Cross-tie Valve
M
M
M
A
M
M
B
73
Secure Cooling Tower Make-up
Makeup Valve
Level Controller
74
Review Questions

• During preparation for Circulating Water
• System Startup, what are the four major
• steps involved?
• What position must the Circ. Water
• Discharge Cross-tie valve be in prior to
• starting the 2nd Circulating Water Pump?
• During Normal Operation, how is ice removed
• from the Cooling Tower?

Click to Review
Click to Review
Click to Review
When you are sure you can correctly answer these
question click the Button to
continue