Field of the invention
[0001] The present invention relates to a method for reducing the moisture content of the
air of a first defined space in communication with, via an entrance to said first
defined space, at least one second defined space, the air of first defined space having
lover moisture content than that of said at least one second defined space, whereby
the reduction of the air moisture content is achieved by at least one means for dehumidifying
air.
Background of the invention
[0002] Although, in the description below reference is made to a cold-storage room, it should
be noted that method according to the invention can be used in connection with other
types of rooms or warehouses or defined spaces to which one should have access to
and in which the air moisture content should be reduced compared with the air moisture
content outside said defined space. One example is a room for manufacturing lithium
batteries, the air moisture content of which is reduced.
[0003] A problem with cold-storage rooms for goods, to which one has access to through some
type of entrance or door, is that the air outside said rooms usually have higher moisture
content than the air inside said rooms, which results in the formation of air frost
and ice on the surfaces of said rooms and the goods stored therein. This problem is
accentuated on the surfaces of cooling equipment used for cooling said rooms.
[0004] One way of eliminating this problem is to arrange an air lock in connection with
the door to the cold-storage room. To further improve the efficiency of the air lock
it is known to supply dried air to said air lock. However, to dry said air energy
is consumed, and due to increasing energy costs solutions are sought to reduce the
energy needed to dry said air supplied to the air lock and to increase the degree
of dryness of the air supplied to the cold-storage room.
[0005] In connection with, for instance, the room for manufacturing lithium batteries the
problem with the formation of air frost and ice does not exists, but still has the
problem with high energy costs, and also the aim at increasing the degree of dryness
of the air supplied to said room.
[0006] The object of the invention is thus to obtain a more efficient way of providing the
dried air to the cold-storage room or other spaces, the air of which has a less moisture
content than the air outside said cold-storage room or space, to less costs and with
higher degree of dryness. In so doing it is possible to use a dehumidifier or other
means for drying/dehumidifying air with less capacity and which thus is less expensive.
[0007] This object is achieved according to the invention by a method for reducing the moisture
content of air of a first defined space in communication with, via an entrance to
said first defined space, at least one second defined space, the air of first defined
space having lower moisture content than that of said at least one second defined
space, whereby the reduction of the air moisture content is achieved by at least one
means for dehumidifying air,
characterized by
taking air having higher moisture content than the air of the first defined space,
drying said air by said at least one means for dehumidifying air, and feeding said
dehumidified air wholly or partially to the first defined space.
Brief description of the invention
[0008] A non-limiting example of the present invention will be described hereinafter with
reference to the accompanying drawing on which Fig. 1 is a schematic view of a known
arrangement of a cold-storage room having an air lock to which dehumidified air is
supplied, Fig. 2 is a schematic view of the most generic form of the method according
to the invention applied to at least on defined space in a series of one or several
defined spaces, and Fig.3 shows a cold-storage room having an air lock divided into
two compartments, whereby the dehumidified air is supplied to the compartment of the
air lock situated closest to the room which should contain air having low moisture
content.
Description of preferred embodiments
[0009] Fig. 1 shows a cold-storage room the entrance of which is provided with an air lock
according to prior art. Air from the air lock is feed to a dehumidifier which is dehumified/dried
by said dehumidifier, and the dried air is feed back to the air lock. In a typical
case the air in the cold-storage room should have a moisture content of about 0.5
grams water/kg air at -25°C.
[0010] Fig. 2 is a schematic view of the most generic form of the method according to the
invention applied to at least on defined space in a series of one or several defined
spaces which are in communication with each other via some type of door or doorway.
As can be seen from said Fig. 2 air with higher moisture content in a first defined
space is feed to the dehumidifier, and the dried air is feed to a second defined space
having air with lower moisture content than the first defined space. Preferably the
first defined space is separated from the second defined space by some type of partition
means, for instance, a plurality of elastic stripes positioned adjacent to each other
or at least one swing door.
[0011] A preferred embodiment for carrying out the method according to the invention is
shown in Fig. 3. The entrance to the cold-storage room is provided with an air lock.
Said air lock is divided into at least two serially connected compartments by partition
means, preferably of the type mentioned above. Air from the compartment of the air
lock having highest moisture content is feed to a dehumidifier or some other type
of means for dehumidifying air and dried, and then feed wholly or partially to the
compartment of the air lock located closest to the entrance of cold-storage room.
Said entrance may be provided with some type of partition means, preferably of the
above-mentioned type.
[0012] As can be inferred from the above the first defined space and the compartments of
the second defined space have all communication with each other, although some type
of partition means is or may be provided between said spaces.
[0013] In a typical example the air of the compartment having highest moisture content has
a water content of 2 grams/kg air (indicated by numeral 2 in said Fig. 3). Said air
is dried to a water content of 0.2 grams/kg air (indicated by numeral 0.2 in said
Fig. 3) which results in a water content in the cold-storage room of less than 2 grams
water/kg air, preferably 0.5 grams water/kg air, at a temperature of -25°C.
[0014] The method according to the invention is thus characterized by dividing said at least
one second defined space into two serially connected compartments by said partition
means, taking wholly or partially the air having higher moisture content from the
compartment of the second defined space located longest from the first defined space,
dehumidifying said air, and feeding said dehumidified air wholly or partially to the
compartment of the second defined space located closest to the first defined space
which has communication with the said compartment of he second defined space.
[0015] Of course, as is obvious for the man skilled in the art, the second defined space
may be divided into more the two serially connected compartments, for instance, three.
1. Method for reducing the moisture content of air of a first defined space in communication
with, via an entrance to said first defined space, at least one second defined space,
the air of first defined space having lower moisture content than that of said at
least one second defined space, whereby the reduction of the air moisture content
is achieved by at least one means for dehumidifying air,
characterized by
- dividing said at least one second defined space into two compartments arranged in
series and communicating with each other via partition means,
- taking wholly or partially air having higher moisture content from the compartment
of the second defined space located longest from the first defined space,
- dehumidifying said air, and
- feeding said dehumidified air wholly or partially to the compartment of the second
defined space located closest to the first defined space.
2. Method according to claim 1, characterized by
said at least one second defined space being an air lock through which entrance is
made to the first defined space.
3. Method according to claim 1, characterized by the entrance to the first defined space being provided with partition means.
4. Method according to claim 1, characterized by the means for drying air being at least one dehumidifier.
5. Method according to claim 1, characterized by the first defined space being a cold-storage room.
6. Method according to claim 1, characterized by the first defined space being a space having a moisture content of less that 2 grams
water/kg air.
7. Method according to any of claims 1-6, characterized by forming the partition means of a plurality of stripes positioned adjacent to each
other.
8. Method according to any of claims 1-6, characterized by forming the partition means of at least one swing door.