This paper presents the experimental tests on the chemical dehumidification of air by a liquid desiccant and desiccant regeneration carried out in an absorption/desorption tower with random packing. The experimental set-up is fully described together with measure-ments, procedures, data reduction, and accuracy. The experimental tests include 46 de-humidification runs and 38 desiccant regeneration runs carried out with the traditional hygroscopic solution H2O/LiBr and the new solution H2O/KCOOH in the typical op-erative ranges of air conditioning applications. The experimental results are reported in terms of humidity reduction, desiccant concentration change, and tower efficiency. The experimental tests show that chemical dehumidification of air by liquid desiccants ensures consistent reduction in humidity ratio, which is suitable for the application to air condi-tioning or drying processes. The experimental results are also compared to a one-dimensional simulation code of a packed tower: a fair agreement was found between experimental and calculated performance. 21204
1 Introduction
The sorption dehumidification of air by liquid desiccants could
represent an interesting alternative to traditional dehumidification
processes by air cooling below the dew point which involve both
cooling and heating capacity. Chemical dehumidification by solid
or liquid desiccants allows consistent humidity reduction and its
energy cost, due to desiccant regeneration, can be significatively
reduced by proper heat recovery. This process is also useful in
reducing airborne microbial contamination.
Chemical dehumidification had till now few applications. The
most widespread systems are desiccant wheels, which use solid
sorbents ~adsorption!, whereas dehumidifiers using liquid desic-
cants ~absorption!, as a packed column, seem to be more interest-
ing, as they allow heat recovery on desiccant regeneration. These
dehumidification units could be usefully integrated within innova-
tive HVAC plants, particularly with high latent and ventilation
loads or when a high indoor air quality is required. The authors of
the present paper have designed HVAC plants based on chemical
dehumidification for an educational building @1# and for an infec-
tious disease hospital @2#. Recently an innovative HVAC system
based on chemical dehumidification by liquid desiccants has also
been proposed by @3#. Dehumidification units based on liquid des-
iccants have been commercially available since about 1935, and
have been used in a variety of industrial and institutional HVAC
systems @4#. More recently, in 1997, a compact air conditioning
system, which includes a dehumidification and a regeneration unit
integrated with a regenerative heat pump, was commercialized
@5#.
In open literature it is possible to find several works on the
theoretical analysis of heat and mass transfer in the packed col-
*Corresponding author.
Contributed by the Solar Energy Division of THE AMERICAN SOCIETY OF ME-
CHANICAL ENGINEERS for publication in the ASME JOURNAL OF SOLAR ENERGY
ENGINEERING. Manuscript received by the ASME Solar Energy Division, Nov.
2002; final revision, Apr. 2003. Associate Editor: V. C. Mei.umns for chemical dehumidification of air @6–8# together with
experimental data on the performance of absorption/desorption
packed towers @9–14#.
This paper presents the experimental tests on the sorption de-
humidification of air by a liquid desiccant and desiccant regenera-
tion carried out in an absorption/desorption tower with random
packing by using the traditional hygroscopic solution H2O/LiBr
and the new solution H2O/KCOOH in the typical operative ranges
of air conditioning applications. The new desiccant, usually used
as brine, is less corrosive and expensive than the traditional ones 填料塔英文献和中文翻译:http://www.751com.cn/fanyi/lunwen_13304.html