High Performance Single Effect Absorption Chiller
50 to 1700 Tons
Importance of Absorption Chillers
New laws about limitation in using chlorofluorocarbon refrigerants (CFC) which
has an important role, in ozone depletion and global warming, the present laws
in utilization with high efficiency in utilizing from electric energy, a
tightening electricity supply and dramatic increases in electrical energy and
demand cost... These complex issues challenge today’s HVAC system designer
alternatives to traditional compression refrigeration chillers.
One
such alternative is the absorption chiller. Absorption chillers are heated by
steam or hot water and/or direct gas fired which includes the main consuming
(energy) and by considering its cycle creates cooling. There, against the
traditional compression refrigeration chillers needs low quantity of electric
energy. Cycle working fluid of absorption chillers does not create damage to
environment and atmosphere of the earth.
Capabilities mentioned for
absorption chillers are main reason for the base of research work and
manufacturing in Naghashian factory (NF). NF working in manufacturing HVAC
systems in Iran for more than 40 years, has taken required action to perform
necessary calculations and manufacturing absorption chillers of Lithium Bromide
and water (LiBr+H2O) type with single shell form for the last one year.
Therefore, this factory has changed in to a big supermarket in the field of
HVAC.
Base of designing the absorption chillers in this factory is
performed by computer software and designed in such a manner similar to
absorption chillers and requires low dimension (volume) at the location. To be
noted that against each partial and total part used in the system is together
with continuous analysis and test. Meanwhile, this factory is succeeded to
establish an operational line for the test of one of the chillers manufactured
in this factory. Results obtained by this test resulted to correction and
development of computer software and therefore, by designing single stage hot
water and/or steam fired absorption chillers from 50 to 1700 tons cooling
capacity is presented in the local and foreign markets.
Cycle of Absorption Chillers
Cycle of absorption chiller from pure water is used as a refrigerant and from
heat as an input energy and creates chilled water for comfort or process
applications. In the cycle of absorption chiller steam or hot water, and/or any
other heating source as an input energy, resulted to separation of water vapor
from the dilute solution of LiBr+H2O in the chiller generator. The water vapor
produced is drawn through the condenser, where it gives up heat to the cooling
tower water and through the absorption process, cools the system circulating
water. This process is illustrated in the flow diagram below. The thermal
efficiency of components of cycle and quantity of dilute solution in
circulation in absorber is considered in such a manner that resulted to
improvement and optimization of cycle of single stage absorption chiller and in
addition increase in coefficient of performance up to 0.75, has saved the cycle
from the, critical condition resulted to probable increase in the
crystallization of solution in the output of the cycle heat exchanger unit.
General and Standard Specification
All The components of absorption chillers are manufactured in NF as per
necessary international standards. All NF single-stage absorption chillers are
fully assembled together with necessary leak tests in the factory and ship in
one piece. Pumps used in the unit of types of low NPSH required and without
mechanical sealing, and prepared by accredited international companies. In
chillers with low cooling capacity two pumps are used, one is for refrigerant
line and another for weak solution line and one liquid jet pump which has
designed and produced in NF, is used in intermediate solution line. Whereas in
chillers with high cooling capacity three pumps are used: LiBr+H2O used in
these chillers for controlling corrosion and increasing absorption process
speed in cycle is together with standardize additives, and in the factory after
complete discharge of the absorption chillers are charged to them.
Controlling Specification
The chillers are designed in such a form that the absorption process in them,
not to face with the difficulty of crystal and resulted to their correct
operation in the condition of full loads and/or partial loads. System resulted
to anti-crystallization of solution in the cycle, operates automatically. This
system is designed in such a manner that immediately after the occurrence of
difficulty in cycle which resulted to crystallization of solution, dilutes the
solution automatically by the refrigerant in cycle. In this case the
crystallization of solution continues immediately will shut down the machine.
Working Limits Specification
These types of chillers are designed in such a manner that able to use the steam
up to the pressure of 14[psig] and/or hot water up to the temperature of
270[F], produces chilled water within the temperature of 40[F] to 50[F], and to
operate up to the minimum temperature of 55[F] for water in the circulation of
cooling tower in a suitable condition. Meanwhile, it is possible to have
suitable operation with energy even with low quality. Therefore, it has
obtained special importance for the application of energy saving like, reuse,
of waste energy and cogeneration in power plants and similar cases.
Obligations of Naghashian Factory
NF is providing two years guarantee and period of minimum ten years of
after-sale service and any of other necessary obligation for the confidence of
its customers.
|
