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Flow Diagrams

Overall system
Chiller cycle

Chiller schematic

Overall System

The overall system, shown in Figure 1, consists of the chiller, connections to city water and chilled water, an electric boiler to generate steam, and a heat exchanger to serve as a test load and to return water at a variable temperature to the chiller.

Overall system

Figure 1. Overall system

ALC         = Automated Logic Control system
BHWSV    = Hot Water Supply Valve 
BFP          = Boiler Feed Pump
BFT          = Boiler Feed Tank
CR           = Condensate Return
CTW         = City Water
ESB          = Electric Steam Boiler
HWR         = Hot Water Return
HWS         = Hot Water Supply
IV#          =  Chilled Water Shut-off Valve
P#            = Pressure transmitter
SS            = Steam Supply
T#            = Temperature transmitter
TLHX         = Test Load Heat Exchanger
WS           = Water Softener 

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Chiller Cycle

Figure 2 shows the steam driven LiBr-water chiller flow diagram.  It is a parallel flow, double effect device.  "Double effect" means that there are two stages of absorber solution regeneration and steam refrigerant vaporizatonand condensation.  "Parallel flow" means that the dilute sorbent from the absorber is split and fed to both regenerator stages in parallel.

Chiller Cycle
             Figure 2. Chiller cycle

Chiller Schematic

Figure 3 shows the Broad BCT16 chiller flow diagram, with representative temperatures.

Chiller schematic
           Figure 3. Chiller schematic


ABS       =    Absorber
BPHX     =    By-pass heat exchanger
CHSV     =    Cooling/heating switch valve
CHWP    =    Chilled water pump
COND    =    Condenser
CT         =    Cooling tower
CTF        =    Cooling tower fan
CTWS     =    City water switch
CWBPV   =    Cooling water by-pass valve
CWDD     =     Cooling water drain device
CWDV     =    Cooling water detergent valve
CWOF     =     Cooling water overflow
CWP       =    Cooling-water pump
EVP        =    Evaporator
HRHX      =    Heat recovery heat exchanger
HTHX      =    High-temperature heat exchanger
HTRG      =    High-temperature regenerator
LTHX       =    Low-temperature heat exchanger
LTRG       =    Low-temperature regenerator
RBPV       =    Refrigerant by-pass solenoid valve
RP           =    Refrigerant pump
RPH         =    Refrigerant pump heater
SF           =    Steam filter
SP           =    Solution pump
ST           =    Steam trap
SV           =    Steam valve

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Additional information can be found in the thesis of Hongxi Yin "An Absorption Chiller in a Micro BCHP Application: Model based Design and Performance Analysis" (pdf) (Appendices 1A, 2A, 2B, 3A, 4A)