This presentation is about cooling tower & cooing water treatment & cooing water problems. In the end the presentation can able to understand about operation & monitoring of cooling water.

1. “PREPARATION ON #300 AREA”
IW SUPPLY SYSTEM
PREPARED BY : JAYPALSINH BORADHARA
EMPLOYEE CODE : Y00550
DEPARTMENT : UTILITY (W22)
DATE : 18--2017

2. PRESENTATION OUTLINE
 SCHEMATIC DRAWING OF WATER
TREATMENT SECTION
 ABOUT #300 AREA (COOLING TOWER)
 WATER IMPURITIES & ITS EFFECT
 COOLING WATER PROBLEMS
 SUPPLY FLOW RATE & REQUIREMENTS
 MAIN SPECIFICATION OF COOLING TOWER
 SITE PICTURES
 MASS FLOW BALANCE SHEET

3. 100 #
Treated Water plant
300#
IW cooling
system
UTILITY CONTROL
BUILDING
800#
PA Station
400#
DM WATER PLANT
WATER SYSTEM
700#
WASTE WATER TREATMENT PLANT
N2 & H2
STATION
NG
STATION
SCHEMATIC DIAGRAM

4. COOLING TOWER
Cooling towers are heat removal devices
used to transfer process waste heat to
the atmosphere. Cooling towers may either
use the evaporation of water to remove
process heat and cool the working fluid to
near the wet-bulb air temperature or, in the
case of closed circuit dry cooling towers, rely
solely on air to cool the working fluid to near
the dry-bulb air temperature.

5. TYPES OF COOLING TOWER
COOLING TOWERS
Natural Draft Mechanical Draft
Design of Cooling tower is
such that cold air at the
bottom of tower pushes the
warmer air out from top.
Forced Draft
Air is pushed in
the tower with a
fan at the side.
Induced Draft
Air is pulled from
cooling tower by
a fan at the top
Counter Flow Cross Flow

6. TYPES OF COOLING TOWER
Natural Draft
Forced Draft

7. TYPES OF COOLING TOWER
Counter Flow Cooling Tower

8. CSCI-COOLING TOWER

9. FRAME & CASING – support the exterior enclosures
FILL- to facilitate heat transfer by maximizing water & air contact
COLD WATER BASIN- the basin usually has a sump or low point for
the cold water discharge connection.
DRIFT ELIMINATORS - these capture water droplets entrapped in the
air stream that, otherwise would be lost to the atmosphere
LOUVERS – the purpose of louvers is to equalize air flow into the fill
and retain the water within the tower. mostly used in cross flow.
NOZZLES – these provide the water sprays to wet the fill.
FANS – propeller & centrifugal are generally used in cooling tower.
propeller fan is generally used in induced draft.
COOLING TOWER COMPONENTS

10. COOLING TOWER PERFORMANCE
COOLONG TOWER
PERFORMANCE :
COOLONG RANGE :-
RANGE = HOT WATER
TEMPRATURE – COLD
WATER TEMPERATURE
COOLING TOWER
APPROACH :-
APPROACH = COLD WATER
TEMPERATURE – WET BULB
TEMPERATURE

11. EVAPORATION E:-
E = ∆T × R × 0.00085 (T in °F)
E = ∆T × R × 0.00153 (T in °C) Where,
where, E=Evaporation
R= Recirculating Rate in (m3/hour)
Temperature drop ∆T:-
∆T= TR – TS where TR – inlet temp.
TS – outlet temp.
Make up Water MU:-
MU = E + BD where, MU = make up rate (m3/hour)
E = evaporation rate (m3/hour)
BD = blowdown rate (m3/hour)
COOLING TOWER CALCULATION

12. COOLING TOWER CALCULATION
BLOW DOWN RATE BD:-
BD= E/CR-1 Where, BD = blowdown rate (m3/hour)
E = evaporation rate (m3/hour)
CR = cycle of concentration
 CYCLE OF CONCENTRATION :-
C.O.C = TSS in recirculation water
TSS in make up water

13. COOLING WATER PROBLEMS
MICROBIOLOGICAL
GROWTH
FOULING

14. CORROSION
 An electrochemical process in which a metal in it’s elemental
form returns to it’s native.
WATER (ELECTROLYTE)
O2
Fe(OH)2
ANODE
Fe
++
ELECTRON
FLOW
CATHODE
OH
-
O
=
O2
H O2
3
Fe(OH)

15.  Reduced heat transfer (lost efficiency)
 Increased cleaning (added costs and hassle)
 Equipment repair and replacement (lost revenue)
 Process or waste–side contamination (poor product
quality)
 Unscheduled shutdown (lost revenue)
CONSEQUENCE OF CORROSION

16. TYPES OF CORROSION
Uniform corrosion
or
Localized corrosion
Macroscopic
Other
Microscopic
• Galvanic
• Concentration Cell
• Pitting
• Selective Leaching
• Microbiological
• Erosion Corrosion
• Intergranular
• Corrosion Fatigue
• SCC

17.  Two dissimilar metals in contact with an
electrolyte
 Anode and Cathode in different metals
 One metal is the anode, the other is the
cathode
 One metal corrodes, the other is protected
Galvanic Corrosion
Brass Bolt
Aluminum
Electrolyte
Corroded Zones

18. Galvanic Corrosion

19. CONCENTRATION CELL
 Anode and Cathode in same metal (c.f.
galvanic corrosion
 Anode becomes localized by some mechanism
that makes it the preferred site
 Can occur at crevices or under deposits

20. CONCENTRATION CELL

21. PITTING
 Caused by Localized Deposition & Differential Oxygen cells.
Tuberculation leads to pitting
Water
Iron
Tubercle
Protective Film
Pit Forming
at Small Anodes(陽極)

22. Selective Leaching
Selective removal of one element from an alloy
by corrosion
–Examples:
• Dezincification - removal of zinc from brass alloys
• Graphitization - removal of Fe from cast iron
• Dealuminumification - removal of Al from aluminum
bronzes
• Denickelification - removal of Ni from Cu: Ni Alloy

23. Selective Leaching
Denickelification of Cu:Ni AlloyDezincification of Admiralty Brass

24. Erosion Corrosion
• Via compact(high speed water flow or
suspended solid)
• Rate of corrosion affected by:
– Velocity
– Turbulence
– Impingement
– particulate solids
 Copper alloys particularly susceptible as
soft

25. Erosion Corrosion

26. Microbiological corrosion

27. STRESS CORROSION CRACKING(SCC)
 Localized attack due to a combination of surface
tensile stress, temperature and a corrosive
environment
 Either inter or transgranular
 Certain ions are particularly aggressive to certain
metals

28. SCC Failure

29. SCALE TYPES
•sludge
•Organic and oil
•precipitation
•Corrosion product
•Microorganism product

30. FOULANTS
• Mud / Silts
• Organics / Oils
• Dust / dirt
• Matter precipitated in
bulk water
• Corrosion products
• Microorganisms

31. FOULANTS
• Suspended Solids - settle in low flow areas
–obey Stokes Law
–shell-side coolers, plate exchangers
• Organic materials and microorganisms can act
as binding agents
• Do not form scale deposits by themselves

32. MICROORGANISMS POLLUTION

33. MICROORGANISMS FORMING
TYPES
• Algae
• Fungi
• Bacteria
ENVIRONMENT
• Water
• Temperature
• pH

34. o Corrosion inhibitors
o scaling inhibitors
o Dispersant
o H2SO4
o NaOCl
COOLING TOWER DOSING

35. MAIN SPECIFICATION OF COOLING TOWER
1300M3/Hour×2 cells× 45 – 35 ° C Cross flow type
× 29 ° C –W.B (Including 1 set stand by)
Flow rate = 1200 m3/hour
Cycle of concentration = 3 times
Inlet temperature = 45 ° C
Outlet temperature = 35 ° C
Windage loss = 0.22 %

36. • Evaporation loss = 20.7 m3/hour
• Windage loss = 0.24 m3/hour
• Blow down = 10.1 m3/hour
• Make up = 31.1 m3/hour
 Retention Time (T) for cold well = 1258 m3/hour
1200 m3/hour
T = 62.9 minutes.
 IW supply pumps = 720 CMH × 65 M × 3 sets ( Including 1 set
stand by)
 Emergency IW pump = 250 CMH × 60 M × 1 set
MAIN SPECIFICATION OF COOLING TOWER

37. Design Flow rate = 1200 m3/hour
Design temperature : <35°C
Design supply pressure at T.O.P = 4.5 Kg/cm2
pH = 7~8.5
Suspended solid (mg/L) : <30
Total hardness as CaCO3 (ppm) : <800
SUPPLY FLOW RATE & REQUIREMENT

38. SUPPLY FLOW RATE & REQUIREMENT
1) ACL plant requirement = 716 m3/hour
2) Compressed air supply system = 105 m3/hour
3) Utility control Building = 50 m3/hour
4) Auxiliary Building = 243 m3/day
5) Main Substation Building = 76 m3/hour
 Total flow rate = 1190 m3/day
 Design flow rate = 1200 m3/hour
 Design temperature = 45°C

39. SITE PICTURES
RETURN
HEADER
NaOCl
STORAGE
TANK
H2SO4
STORAGE
TANK
COUNTER
FLOW
COOLING
TOWER
EMERGENCY
PUMP ROOM

40. SITE PICTURES
IW SUPPLY PUMP P-
3A01A/B/C
COUNTER
FLOW
COOLING
TOWER
FAN STACK
COLD WELL

41. MASS FLOW BALANCE

42. THANK YOU
ANY QUESTION?