Sorption container for solid sorption medium

A sorption container for solid sorption medium, for example, zeolite, consists at least partially of a flexible metal corrugated hose, whose waves are filled on the inside with sorption medium.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a sorption container for solid sorption 
medium, such as particular zeolites, for example. 
2. Description of Prior Art 
A wide variety of periodically-operating sorption apparatus are known, and 
in general, are characterized by having an adsorption phase and desorption 
phase of operation. In connection with such apparatus in particular, but 
by no means limited thereto, "sorption medium" is generally understood to 
mean substances which absorb during the adsorption phase, a more volatile 
operating medium such as water, for example. 
During the adsorption phase of operation of periodically-operating sorption 
apparatus, adsorption heat is released from the sorption medium, whereas 
during the desorption phase, desorption heat is supplied to the sorption 
medium in order to drive off or evaporate the operating medium. Zeolite, 
for example, is a known sorption medium which together with water as the 
operating medium, forms a pair of sorption substances which can be used in 
numerous applications in the heating and cooling arts. Zeolites are 
crystalline alumino-silicons which are characterized by microscopically 
small hollow spaces wherein water molecules can be stored during the 
adsorption phase, upon releasing heat of adsorption and, as a result of 
their sorption characteristics, offer many advantages over other known 
"sorption mediums". 
German Patent Application DE-OS 35 21 484.4 discloses a particular device 
which uses the sorption characteristics of zeolites in order to generate 
heat and cooling power. Devices of this type always require a sorption 
container which is filled with the sorption medium. The provision and 
release of the heat of reaction is achieved through suitable heat exchange 
surfaces provided to the sorption container. The vapor or steam operating 
medium which is desorbed from the sorption medium (e.g. zeolite) during 
the desorption phase, is discharged from the sorption container through 
suitable vapor flow conduits. This discharged vapor flows into a condensor 
where the vapor condenses into condensate, which eventually is collected 
in a collection container. During the adsorption phase, water (i.e. 
condensate) collected in the collection container, evaporates, and the 
cool vapor flows back into the sorption container, where it is again 
absorbed by the sorption medium, whereupon heat of adsorption is liberated 
and discharged from the sorption container. 
A plurality of requirements must be simultaneously met for a sorption 
container having solid sorption medium. On the one hand, the sorption 
container should have ideal heat exchange characteristics for feeding and 
discharging the "heat of reaction" during the desorption and adsorption 
phases, respectively. On the other hand, the sorption container must 
securely contain and seal off the sorption medium from the outer 
atmosphere, and simultaneously have optimum flow characteristics for 
discharging and feeding the operating medium vapor to the sorption medium 
during the desorption and adsorption phase of operation, respectively. 
Moreover, the sorption container should be made cost effective and must be 
designated specifically for transportable equipment. 
However, prior art sorption containers are generally expensive to 
manufacture, are heavy, poorly seal off the sorption medium from the outer 
atmosphere, and have poor heat exchange capabilities with respect to the 
sorption medium. 
Accordingly, it is a primary object of the subject invention to provide an 
effective sorption container for a solid sorption medium, which can be 
made in a cost effective manner, which is characterized by a weight saving 
and vacuum-proof type of construction, and which permits a good heat 
transfer to and from the sorption medium. 
SUMMARY OF PRESENT INVENTION 
According to one of the broader aspects of the present invention, there is 
provided an adsorption container for containing solid adsorption medium 
capable of adsorbing an operating medium. In general, the adsorption 
container comprises a flexible metal corrugated hose having an inner 
space, a plurality of waves formed therealong, and an adsorption medium 
filler disposed inside the metal corrugated hose and filling the waves. In 
one embodiment, the metal corrugated hose is an annular wave hose, whereas 
in the second embodiment, the metal corrugated hose is a helical wave 
hose. 
Preferably, a flow conduit is formed through the solid adsorption medium 
inside the hose along the axial direction thereof, to allow vapor 
operating medium to flow through the adsorption medium filler. In the 
preferred embodiment, a metal fabric texture is provided to the waves so 
that the adsorption medium is embedded within the metal fabric texture. In 
order to desorb the operating medium from the adsorption medium, a heating 
device can be disposed in the inner space of the metal corrugated hose. 
In one embodiment, the metal corrugated hose has an area which is free of 
adsorption medium, and this adsorption medium free area has sufficient 
heat exchanging surfaces for condensing and/or evaporating the operating 
medium. In this adsorption medium free area, there is provided a shut-off 
means, which is operated (i.e. actuatable) by, for example, deforming the 
metal corrugated hose in either the axial or lateral direction. Extending 
from this length of metal corrugated hose, a smooth piece of pipe (from 
which the waves are typically formed) is provided. Preferably, this pipe 
has a heat exchanging means such as heat exchanging fins, for providing 
improved transmission of heat between the operating medium inside the 
metal corrugated hose and the heat carrier medium flowing over the heat 
exchanging means. In such an arrangement, operating medium vapor is 
desorbed from the adsorption medium filler upon application of heat 
thereto and passes through the opened shut-off means. Thereafter, this 
vapor condenses in the smooth part of the pipe devoid of adsorption 
medium, upon removal of heat from the vapor, through the heat exchanging 
means. 
In another embodiment, the adsorption container of the present invention 
comprises a plurality of metal corrugated hoses combined into a hose 
bundle.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
Referring to FIGS. 1 and 2, there are shown two different types of metal 
corrugated hoses 1 and 1' which are used in constructing the sorption 
container of the present invention. In both types of hoses 1 and 1', the 
swivel-like waves 2 are formed into the tubular surface 3 and 3' 
respectively of the metal hoses, and are shaped so that the inner area of 
the waves are adapted for the reception of the sorption medium e.g., 
zeolite. Notably, in both types of hoses, the inner area of the waves is 
preferably larger in its volume than the outer area over which a heat 
carrier medium, generally air (not shown), is fed to the sorption 
container for the transmission of heat, typically during both the 
desorption and absorption phases. 
In the helical wave hose illustrated in FIG. 1, there are continuously 
connected, right-handed helical waves 3 having a constant pitch throughout 
the total length of the hose. In contrast thereto, in the annular wave 
hose shown in FIG. 2, there is a plurality of closed waves 3' each having 
the same distance with respect to each other, whose main plane is vertical 
with respect to the hose axis. 
Referring to FIG. 3, there is shown a cross-sectional longitudinal view of 
one embodiment of the sorption container of the present invention. The 
sorption container comprises metal corrugated hoses 1A and 1B, each 
containing zeolite fillers 4 filling up the waves 2. As shown in FIG. 3, 
an axially-located flow conduit 5 is formed in the fillers 4 so that the 
operating medium vapor may flow therealong and access the sorption medium 
4 without occasioning a vapor pressure drop. In the upper corrugated hose 
1A, the zeolite filler 4 is additionally provided with a fine meshed metal 
fabric 6 into which zeolite is imbedded. This metallic fabric 6 within the 
zeolite filler material 4 serves to increase the stability thereof, and 
simultaneously improves the heat conductivity in the sorption medium (i.e. 
zeolite) itself. 
A heating element (not shown) may also be installed within the metal 
corrugated hoses 1A and 1B along the axial direction thereof, so that the 
sorption medium 4 can be heated as required during any particular 
desorption process. In connection therewith, the installation of a metal 
socket for receiving an electrical heating cartridge is advantageous, for 
example, if the sorption medium should be electrically heated. Also, in 
the event that cooling of the adsorption medium is required, a cooling 
element can be placed on the outside of the metal corrugated hose along 
the axial direction thereof, so that cooling occurs through the surface of 
the metal corrugated hose. 
Annular wave hoses of the type shown in FIG. 2, are commonly made from 
smooth pipes. The smooth pipes 7A and 7B which are used for making the 
corrugated hoses 1A and 1B respectively, are not separated at one end of 
the corrugated hoses. The smooth pipe piece ends 7A and 7B which remain 
during manufacturing of the waves 2, are typically designed with a 
gradient or bend with respect to annular wave hoses 1A and 1B. As shown in 
FIG. 3, these smooth pipe piece ends are also provided on the outer 
surface area thereof, with correspondingly apertured thin-sheet metal 
plates (i.e. heat exchanging fins) 8 and are mechanically connected with 
the smooth pipe ends in a good heat conducting manner. Notably, these heat 
exchanging fins 8 ensure a good heat transmission to and from the 
operating medium within the smooth pipe 7A and 7B. To ensure this good 
mechanical and thermal connection, the pipes have been widened, for 
example, by means of a mandrel which is introduced into the pipes until 
the thin sheet metal plates 8 are mechanically connected with the smooth 
pipes 7A and 7B in a good heat exchanging manner. Thus, for example, when 
cool air is fed over the thin sheet metal plates 8, vapor operating medium 
desorbed from the zeolite filler 4 is condensed inside the smooth pipe 
pieces 7A and 7B (which function as condensors). In turn, the condensate 9 
formed along the pipe pieces, can run off into a collecting container (not 
shown) when the pipe pieces are disposed in a declined position with 
respect to the corrugated hoses 1A and 1B, as shown in FIG. 3 in 
particular. 
In another embodiment of the present invention, a plurality of metal 
corrugated hoses such as 1A and 1B for example, can be arranged into 
bundle-like configuration. In such an embodiment, all of the smooth pipe 
ends 7A, 7B . . . can be commonly equipped with the heat exchanging fins 8 
fixedly attached onto the smooth pipe ends by widening the pipe pieces. In 
this manner, an air-cooled condenser realized thereby, can be provided to 
this bundle-like configuration, in a weight saving manner, while not 
requiring any additional welding or soldering. 
FIG. 4 shows a longitudinal cross-sectional view of a section of another 
embodiment of the sorption container of the present invention. In general, 
the sorption container hereof comprises left and right side portions of 
the corrugated metal hose 1C. On the left side portion of the corrugated 
hose 1C, there is provided solid sorption medium 20 which fills the waves 
21 of the hose to provide a sorption medium filler. Formed through the 
sorption medium 20, is a flow conduit 22 which allows for the passage of 
vapor operating medium as described hereinabove. As shown in FIG. 4, the 
right side of the corrugated hose 1C, is free of sorption medium, and a 
shut off means and liquid operating medium are contained therein instead. 
As illustrated in FIG. 4, the shut off means comprises an apertured disk 23 
which, along its outer area, is formed into a wave 21A of the corrugated 
hose 1C, in a vapor tight manner. The apertured disk 23 serves as a seal 
seat for a stanchion 24 provided with a packing 25. The stanchion 24 is 
mounted on the end cap 26 of the metal corrugated hose by means of a 
linkage 27. During a movement of the metal corrugated hose 1C in axial 
direction, the shut off means can be automatically opened or closed, as 
desired. In sorption apparatus under vacuum pressure, the shut off means 
in the rest position remains closed due to the flexibility of the 
corrugated hose. The shut off means can be opened by applying an outside 
force, which causes an expansion (i.e. elastic deformation) of the metal 
corrugated hose between the apertured sheet metal disk 23 and end cap 26, 
so that the operating medium can evaporate, flow through flows conduit 22, 
and adsorb into the sorption medium 20. In this particular embodiment, a 
leakage free shut off means is provided which can be made in a very cost 
effective manner. The inner region of corrugated hose 1C between the 
apertured disk 23 and the end cap 26, is additionally covered with an 
absorbent material 28 such as metal texture. This absorbent material 28 
uniformly distributes the condensed operating medium in the right hand 
portion of hose 1C, during the desorption phase of operation, and 
simultaneously acts as a drip separator for vapor operating medium during 
the adsorption phase. 
It is particularly advantageous to bend each metal corrugated hose in the 
center by about 180.degree. and to arrange the two hose shanks parallel 
with respect to each other. In this manner, one costly locking cap per 
wave hose can be saved. This is particularly advantageous where the 
sorption container comes in contact with hot exhaust gases, since welded 
or soldered end caps would require a high manufacturing effort in this 
aggressive (i.e. hot exhaust gas) medium. 
On the right side portion of the metal corrugated hose 1C, during the 
adsorption process, the heat adsorbed from the liquid operating medium to 
evaporate a portion thereof, rapidly lowers the temperature of the 
remaining amount of liquid operating medium in the hose. The cooling power 
which is generated by this evaporation during the adsorption process, can 
be transmitted over the surface of the corrugated hose in a particularly 
efficient manner, for a variety of purposes. 
Metal-corrugated hoses for use in carrying out the present invention are 
described, for example, in the Taschenbuch Nr.301, Ausgabe 1984. of Fa. 
Witzenmann GmbH Metallschlauch-Fabrik Pforzheim. In accordance therewith, 
the base material for corrugated hoses are either seamless or 
longitudinally welded relatively thin-walled pipes. In these relatively 
thin-walled pipes, the swivel-like waves 2 can be impressed into smooth 
pipes, by means of special hydraulic tools. Alternatively, thin-walled 
bands of metal can be provided with wave-like profiles using a continuous 
metal forming process, then wound about on appropriate hose diameter, and 
thereafter welded together to form a relatively thin-walled pipe with 
swivel-like waves 2. Using this principle of corrugated metal hose 
construction, waves 2 having an increased height dimension can be 
produced, into which additional sorption medium can be filed. Also, such 
constructed metal configurated hoses typically will have a better than 
average resistance to operating medium pressure. 
Metal corrugated hoses used in constructing sorption containers of the 
present invention, have the advantage of being absolutely sealed tight 
from external atmosphere, and have a large pressure resistance and low 
space requirements. Marketable production sizes for metal corrugated hoses 
for use in the sorption container the present invention, typically are 
between 3 to 350 mm inside diameter. The permissible operating pressures 
using such metal corrugated hoses, may reach up to 500 bar. An operating 
temperature threshold of up to about 650.degree. C. is assured using metal 
corrugated hoses of the present invention, however such a threshold is 
dependent on the operating pressure. 
In addition to the already mentioned advantages of metal corrugated hoses 
of the present invention, an optimal heat transmission to and from the 
sorption medium is made possible. The sorption container of the present 
invention may be adjusted to the given heat carrier medium, by selecting 
appropriate dimensions for the wave hose diameter and/or the distance(s) 
between waves 2 of the metal corrugated hose hereof. 
A good heat exchange with the sorption medium is assured in view of the 
high flexibility of the metal corrugated hose of the present invention. In 
particular, in equipment under vacuum, the wave flanks shown in FIGS. 1, 3 
and 4 are pressed onto the sorption medium by the outer excess pressure 
provided by the air pressure outside the hose. This external air pressure 
causes the hose to contract inwardly, pressing the waves flanks against 
the sorption medium filler 4, resulting in a good heat conductivity 
through the sorption medium filler 4 and hose, to the ambient atmosphere 
outside the hose. 
When using a helical wave hose, a heat carrier medium can be fed 
transversely to the metal corrugated hose of the present invention. Also, 
such a hose can be more strongly subjected to turbulence in comparison 
with the annular wave hose. 
A particularly effective application of the metal corrugated hose hereof is 
provided when the portion of the hose having no sorption medium present, 
is contacted with a heat carrier of a temperature different than the 
temperature of the portion of the hose filled with the sorption medium. In 
this manner, for example, the sorption medium portion of the hose hereof 
may be used as a condenser or evaporator for the operating medium. 
While the particular embodiment shown and described above has proven to be 
useful in many applications involving the adsorption arts, further 
modifications herein disclosed will occur to persons skilled in the art to 
which the present invention pertains and all such modifications are deemed 
to be within the scope and spirit of the present invention defined by the 
appended claims.