Plate Type Heat Exchangers; Parallel Flow; High Temperature Generator (Htg); Low Temperature Generator (Ltg) - York YHAU-CW Manual

Double effect steam-fired absorption chiller
Table of Contents

Advertisement

SECTION 2 – PRODUCT DESCRIPTION

PLATE TYPE HEAT EXCHANGERS

The diluted (weak) lithium bromide solution leaving
the absorber section is pumped through various plate
type heat exchangers (such as the low temperature heat
exchanger, low temperature steam drain cooler, high
temperature heat exchanger, high temperature steam
drain cooler and LTG refrigerant condensate heat ex-
changer) before it enters the high temperature gen-
erator and low temperature generator sections. These
plate type heat exchangers improve cycle efficiency by
pre-heating the dilute solution. Pre-heating the dilute
solution reduces the load of the driving heat source in
the high temperature generator section. The concen-
trated solution flows out of the generators and back
through the various heat exchangers.
The relatively high temperature solution streams from
the two generators and the heat of the steam conden-
sate is used to pre-heat the weak solution stream leav-
ing the absorber.
To Absorber
Sprays
Low Temp.
P2
Heat Exchanger
Dilute Solution
from Solution
Pump
18
High Temp
Heat Exchanger
High Temp. Steam
Drain Cooler
LD19871c1

PARALLEL FLOW

The unique parallel flow divides the solution between
the low temperature generator and the high tempera-
ture generator sections into two parallel, balanced
paths. The result is a safer and more efficient operation
at a much lower pressure than conventional series-flow
designs. The various solution to solution plate type
heat exchangers optimize efficiency by enabling effec-
tive heat transfer between the diluted (weak) and the
concentrated lithium bromide solutions.

HIGH TEMPERATURE GENERATOR (HTG)

The high temperature generator section is a flooded de-
sign. The steam passes through the stainless steel tubes
and further heats up the pre-heated dilute solution from
the high temperature heat exchanger and high tempera-
ture steam drain cooler.
The hot refrigerant vapor boiled off from the dilute
solution is sent to the low temperature generator. This
leaves behind strong solution which is returned to the
high temperature heat exchanger.

LOW TEMPERATURE GENERATOR (LTG)

The hot refrigerant vapor from the high temperature
generator heats up the dilute solution coming from the
low temperature heat exchanger and low temperature
steam drain cooler. The additional refrigerant vapor
produced migrates to the condenser. The refrigerant
vapor from the high temperature generator condenses
into liquid and flows to the condenser.
The low temperature generator is a falling film design,
ensuring superior heat transfer and enhanced life by
eliminating wear and tear at the tube supports.
FORM 155.31-ICOM2.EN.UL
ISSUE DATE: 12/21/2018
JOHNSON CONTROLS

Advertisement

Table of Contents
loading

Table of Contents