ACADs (08-006) Covered

KeywordsChilled Water System

Description

Supporting Material

5.2.2.4

2

OBJECTIVES

1. State the purpose of the Chilled Water System.

2. State the basic function of each major component in the Chilled Water System.

3. Describe how heat is transfer into and out of the Chilled Water System.

5

Refrigeration Cycle

ChillWater

HeatSink

6

Economizer / Evaporator

COMPRESSOR

FIXED ORIFICE

CONDENSER TPCWCHILLED WATER

COLD

WARM

WARM

COOL

HOT

COOL

HOT

COLDLIQUID REFRIGERENT SAME PRESSURECOOL TEMPERATURE

GASEOUS REFRIGERANTHIGH PRESSUREHIGHER TEMPERATURE

GASEOUS REFRIGERANTWARMLOW PRESSURE

LIQUID/GAS MIXTUREREFRIGERANT LOW PRESSUREVERY COLD TEMPERATURE

HP LIQUIDLP LIQUID /LP GAS

LP GAS HP GAS

REFRIGERATIONCYCLEEVAPORATOR

7

Purpose

The Chilled Water System provides chilled water throughout the plant to all air conditioning and air cooling units that are required during plant operation.

8

9

Components

• Chillers• Chilled Water Pumps• Chilled Water Expansion Tank• Air Separators

10

Chillers

• Three chiller units provided

• Each unit consists of a 1500-ton centrifugal compressor

• Any two units may operate in series with the third unit in standby.

11

12

13

Chilled Water Pumps

• Three horizontal centrifugal pumps are provided to move the chill water through the system (two normally running with one in standby).

• Each pump is rated at 150 hp at a design flow rate of 3027 gpm.

15

16

Chilled Water Expansion Tank

• Maintains NPSH to the chilled water pumps.

• Allows for chilled water expansion on temperature fluctuations.

17

18

Air Separator

• Air removal from the water– Reduces corrosion of the piping network– prevents cavitation of the chilled water pumps

• Air is removed from the chilled water flow stream by utilizing air separator "Tees.“

• Turbulence causes air to be removed from the flow stream.

• The tees direct air to the expansion tank.

19

20

21

22

24

Chilled Water Heat Transfer

• Chilled water circulates through the evaporator to transfer heat to the refrigerant.

• TPCW passes through the condenser to remove heat from the refrigerant.

• The heat, therefore, is transferred from the chilled water to the Refrigerant and from the Refrigerant to the TPCW.

25

Objectives Review

1. State the purpose of the Chilled Water System.

2. State the basic function of each major component in the Chilled Water System.

3. Describe how heat is transfer into and out of the Chilled Water System.

26