填料塔英文献和中文翻译(3)
tower to determine the moisture content change and the tempera-
ture variation for both the air and the solution. A detailed error
analysis indicated an overall accuracy within 610% of humidity
change and within 620% of solution concentration change.
3 Results
Two different sets of experimental tests were carried out: the
first included 20 dehumidification runs with H2O/LiBr and 26with H2O/KCOOH; the second, 26 regeneration runs with
H2O/LiBr and 12 with H2O/KCOOH. When the partial vapor
pressure on the air side was higher than that on the desiccant side
a dehumidification process occurred, on the contrary a desiccant
regeneration process was obtained. Table 2 gives the main opera-
tive conditions under experimental tests: air inlet temperature Tai
and humidity ratio Yi
, solution inlet temperature Tsi
and concen-
tration Xi
, air mass flux G/S and solution mass flux L/S, ratio
between solution L and air G mass flow rates. The air mass fluxes
investigated during experimental tests are set to ensure zero-
carryover conditions and they result lower than the values usually
applied in commercial units. As can be seen, regeneration condi-
tions during experimental investigation were obtained by increas-
ing solution and air inlet temperature up to values around 50 °C.
Figures 2~a! and 2~b! show the humidity reduction measured
during the dehumidification runs against the mass flow rate ratio
L/G. The dehumidification rate depends on the flow rate ratio with
a logarithmic trend, the slope of which increases, in absolute
value, with the air inlet humidity ratio. The solution H2O/LiBr
shows better dehumidification performance than the
H2O/KCOOH solution. The measured humidity reductions are in-
teresting for the application to air conditioning or drying
processes.
Figures 3~a! and 3~b! show the solution concentration increase
measured during the regeneration runs versus the mass flow rate
ratio L/G. The regeneration rate depends on the flow rate ratio
with a logarithmic trend, the slope of which decreases with the air
inlet humidity ratio. The solution H2O/KCOOH shows better re-
generation performance than H2O/LiBr solution.
The performance of a dehumidification/regeneration tower can
be evaluated by a specific tower efficiency as the ratio between
the absolute value of the actual humidity change on the air side
and the absolute value of the maximum humidity change possible
under given conditions:
«tower5uYi
2You/uYi
2Yo.min/maxu
The maximum humidity change is achieved when the partial va-
por pressure of the air at the outlet is equal to the saturation
pressure of the solution at the inlet of the tower. This efficiency is
valid both for dehumidification and regeneration tests.
Figures 4~a! and ~b! show the tower efficiency for the experi-
mental tests carried out. The efficiency increases with the mass
flow rate ratio, with a similar trend for dehumidification and re-
generation tests but with a different absolute value. Dehumidifi-
cation efficiency ranges between 40 and 80–90% with a flow rateratio ranging from 0.2 to 3.0, whereas regeneration efficiency var-
ies from 25 to 75% with a flow rate ratio ranging from 0.3 to 3.0.
The experimental results are also compared to a one-
dimensional simulation code of an adiabatic packed tower de-
scribed in @13#. The whole absorption/desorption column is sub-
pided into an appropriate number of sections, and suitable
subroutines were realized to evaluate heat and mass transfer coef-
ficient in accordance with @6,8,9#. Initial assumptions on outlet
conditions can be verified and adjusted by iteration. The model
上一篇：大型高压泵列车英文文献和翻译
下一篇：机器人平台英文文献和中文翻译