YORK parallel flow and 2-step cycle absorption chiller technology
A challenge in absorption chiller design is engineering a unit that operates furthest from the crystallization line . Johnson Controls absorption engineers accepted the challenge with the development of a parallel flow and 2-step evaporator / absorber design technology .
Typical Industry Flow Cycles
Parallel Series Reverse
|
LTG
ABSO
|
HTG |
Divides the Lithium Bromide ( LiBr ) solution flow between the low-temperature and hightemperature generators into two parallel balanced paths . |
LTG
ABSO
|
HTG |
All of the Lithium Bromide ( LiBr ) solution from the absorber section flows first to the HTG , then to the LTG and back into the absorber section . |
LTG
ABSO
|
HTG |
All of the Lithium Bromide ( LiBr ) solution from the absorber section flows first to the LTG , then to the HTG and back into the absorber section . |
Atmospheric Pressure Limit 760 mm Hg Atmospheric Pressure Limit 760 mm Hg
Atmospheric Pressure Limit 760 mm Hg
HTG Pressure 548 mm Hg
HTG Pressure 660 mm Hg HTG Pressure 638 mm Hg
Abs leaving concentration |
58 % |
62 % |
Abs entering concentration |
Abs leaving concentration |
57 % |
63.5 % |
Abs entering concentration |
Abs leaving concentration |
57 % |
63 % |
Abs entering concentration |
Crystallization Zone |
Crystallization Zone |
Crystallization Zone |
153 ° C HTG temp |
152 ° C HTG temp |
Abs entering temp 43.5 ° C |
Abs entering temp 49 ° C |
Abs entering temp 48 ° C |
Distance from Crystallization Zone 23.5 ° C |
Distance from Crystallization Zone 23 ° C |
Distance from Crystallization Zone 23 ° C |
165 ° C HTG temp
Benefit of Combined Parallel Flow and 2-Step Evaporator / Absorber Technology
LTG HTG
ABSO 1
ABSO 2
2-Step and Parallel Flow
Atmospheric Pressure Limit 760 mm Hg
HTG Pressure 540 mm Hg
Abs leaving concentration
54.5 %
61.5 %
Crystallization Zone
Abs entering temp 47 ° C Distance from Crystallization Zone 29 ° C
Abs entering concentration
151 ° C HTG temp
Combining these two technologies , our two-step and parallel flow design provides the lowest temperature , pressure and concentration . Because this design uses a lower LiBr concentration , it is easier to heat in the generator section . Therefore , it requires a relatively lower grade for the driving heat source , providing a high COP .
YORK parallel flow and 2-step absorption chiller technology operates furthest from the crystallization zone for efficient and reliable operation compared to other designs .
Conditions : Chilled water entering / leaving : 12 ° C / 7 ° C . Cooling water entering : 32 ° C . “ Absorption Chillers – Practice of new operation management ” – 2nd Edition , published by JRAIA , 2017
YORK Air-Conditioning Products 87