Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND AND~SUMMARY OF THE INVENTION
The invention relates to a reaction chamber,
arranged lengthwise and mountable on a chassis, for
continuous biological and/or chemical decontamination of
objects using a mixture of at least hot air and steam.
German Patent Document DE-PS 34 31 719 teaches such
a reaction chamber of this generic type in which, instead
of baskets for receiving any type of object, specially
designed clothes hangers to receive protective clothing
are used. These hangers are hollow inside and have
through holes, so that a gas mixture supplied to the
clothes hangers from above through a pressure tube flows
out of the holes, ventilating the interior of the
clothing. Depending on the position of the hangers on
the conveyor tracks, such internal ventilation alternates
with external ventilation. In both cases, the spent gas
mixture is drawn off again immediately below the clothes
hangers, is cleaned, and fed back again to the hot gas
generator, resulting in a circulatory process. A
plurality of reaction~sections are arranged side by side
along the length of the reaction chamber, to achieve
parallel operation. No spatial separation is provided
between the individual reaction sections.
The above described reaction chamber has the
disadvantage that alternate internal and external
ventilation of protective suits is complicated and
costly. Since nearly the entire hot gas mixture is
transported in a cycle, its preparation and cleaning are
CA 02117839 2004-O1-19
costly. Moreover, as far as the degree of contamination
is concerned it is also disadvantageous that the reaction
sections located side by side are not separated from one
another, and that no clear separation is provided between
the unclean and clean parts of the decontamination
sections.
Because of the hanger construction that serves to
receive articles of clothing and to ventilate them
internally, decontamination is intended primarily for
detoxification of protective suits.
A reaction chamber with a transverse blower is
disclosed in German Patent Document DE-PS 36 25 847, in
which the hot gas mixture is recirculated in the reaction
chamber. In this known device, however, hatched
decontamination is performed, with the articles of
clothing retaining their places in the reaction chamber
during decontamination, a process that is completely the
opposite of continuous decontamination.
The goal of the present invention is to provide a
gas supply and gas exhaust system for a reaction chamber
of a mobile device for continuous decontamination of
objects using a mixture of at least hot air and steam, in
which 'the nature of the objects decontaminated is
variable, and which is simple, economical, and efficient,
in terms of the biological and chemical decontamination
to be performed.
According to the present invention, there is provided
a reaction chamber for continuous decontamination of
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articles, with a mixture of decontaminant gases, said
reaction chamber comprising:
an elongated, tunnel shaped reaction section
which is enclosed along a periphery thereof, said
reaction section comprising at least one path disposed
along a longitudinal axis therein, which path comprises
partial segments located adjacent one another and
sequentially connected to one another;
a conveyor having a guide rail arranged along
said at least one path in said reaction section;
a plurality of gas permeable baskets coupled to
and movable along said guide rail for transporting
contaminated articles through said reaction section;
an entrance door at a beginning of said
reaction section, for entry of baskets into said reaction
section along said guide rail;
an exit door at an end of said reaction section
for discharging baskets from said reaction section;
at least one gas feed for supplying said
mixture of decontaminant gases to said reaction section;
at least one exhaust blower coupled to exhaust
gas from said reaction section, said at least one gas
feed and said at least one exhaust blower being situated
with said reaction section therebetween, whereby an axial
flow of said mixture of decontaminant gases is generated
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along a longitudinal axis of said reaction section, said
flow being in a direction opposite a direction of
movement of said baskets in said reaction section, at
least in a final partial segment thereof,
a plurality of transverse flow blowers situated
along said longitudinal axis; and
a plurality of gas guiding elements coupled to
said transverse flow blowers, for directing flow of said
mixture of decontaminant gases in a direction transverse
to said longitudinal axis.
This arrangement produces a clear separation between
unclean and clean areas, so that a high level of
decontamination and efficiency is achieved in conjunction
with a powerful transverse flow of gases. Preferably, a
conveyor guide rail defines a track or path through the
decontamination section, along which are transported a
plurality of baskets into which articles to be
decontaminated are placed. The transverse flow of hot gases
penetrates the articles in the baskets and is drawn off by
a longitudinal flow generated by a blower at an end of the
reaction section. Regardless of the nature of the articles
to be decontaminated, the transverse flow provides
ventilation, and hence good heat transfer to the articles,
which is critical for biological and chemical
decontamination.
The advantages achieved with the invention consist
in the fact that the hot gas mixture generated by the gas
generator acts in simple fashion on the baskets moved
along a guide. The gas mixture is initially conducted
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through the reaction sections, then drawn off and
exhausted into the open. Because it is exhausted into
the open, no costly preparation of the gas flow is
required as in the known device. The baskets are also
subjected to a powerful transverse flow in which the hot
gas mixture is circulated transversely with respect to
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the lengthwise flow.
Other objects, advantages and novel features of the
present invention will become apparent from the following
detailed description of the invention when considered in
conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 shows a transportable reaction chamber, for
continuous biological and/or chemical decontamination of
articles of clothing and/or equipment according to the
invention, in a perspective and partially cut-away view;
Figure 2 is a franc view of the trailer shown in
Figure l, in section;
Figure 3 is a top view of the trailer shown in
Figure 1, in section;
Figure 4 is a side view of the trailer shown in
Figure 1, in section;
Figure 5 is a~schematic top view of the reaction
chamber shown in Figure 1, in sectian; and
Figures 6 and 7 each show an alternative design for
the reaction chamber, in a schematic top view and in
section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure l shows a trailer 1 in which a device for
continuous decontamination of articles of clothing and/or
equipment is built on a chassis. This embodiment is
designed to decontaminate 62 sets of clothing and
equipment per hour, although it is apparent that other
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designs, with other throughput capacities, can be
utilized within the scope of the invention. The length
of the trailer including the tractor is 16.5 m, its width
is 2.48 m and its height 3.74 m, so that commercial
tractor-trailers suitable for use on the public roads may
be used.
The device for decontamination is divided into an
equipment room 20, a reaction chamber 10, and a loading
and unloading station 30.
Equipment room 20 (Figure 3) comprises a supply tank
22 for water (for example, 800 liters) and a supply tank
21 (for example, 200 liters) to permit independent
operation f_or a period of about 3 hours, a complete
electrical system with an externally mounted motor-
generator set (for example, 6.5 kVA) 23, and a control
system (SPS) 24, which determines the operating mode and
operates the system.,
Reaction chamber 10 (Figure 3) comprises a tunnel-
shaped reaction section 11, a conveyor system for gas-
permeable baskets 19, containing the contaminated
objects, a gas supply'and gas exhaust system for the hot
gas mixture f_or biological and chemical decontamination,
and spray heads for applying a decontamination solution
and for washing it off, for nuclear decontamination.
The loading and unloading station 30 (Figure 2)
comprises a working platform 31, a hot gas generator 32,
and heaters.
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As shown in figure 1, the entire device can be
operated with the trailer 1 uncoupled. After setup, with
working platform 31 and the conveyor system for baskets
19 in place as shown, the operating mode is selected by
the SPS control. A choice can be made between biological
and chemical or nuclear decontamination, as described
hereinafter. While biological and chemical
decontamination is performed with a hot gas mixture,
nuclear decontamination uses liquids.
Two persons are required for decontamination
operation of the complete unit, with their main tasks
being loading baskets 19 with the contaminated objects
and unloading the decontaminated material. Baskets 19
(Figures 1, 2 and 4) are 1.5 m high, 0.5 m wide, and 0.6
m deep, to hold the complete clothing and equipment of a
soldier or a civil defense worker, corresponding to a
total volume of approximately 0.5 m3 and a total weight of
about 40 kg.
The details of the device will first be described
with respect to biological and chemical decontamination.
Before actual operation begins, the entire system is
brought to operating temperature using hot steam
generator 32 (Figure 2) and two additional heaters (not
shown). Experiments have shown that the ideal
decontamination temperature is 170°C, at which chemical
contaminants and weapons or poisons are decomposed into
harmless substances and biological contaminants and'
weapons are destroyed. In the case of objects that are
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sensitive to temperature', the temperature can also be
reduced to 130°C. The decontamination mixture may
consists, for example, of 50o waste gases from a diesel
oil burner and 50°s steam. Other combinations and
percentage mixtures of decontaminant gases may of course
be used within 'the scope of the invention.
The reaction section 11 (Figure 3) is shaped like a
tunnel and enclosed all the way around in cross section.
It has tracks 18 and is composed of two partial segments
11a and 11b located side by side, running in the
lengthwise direction of reaction chamber 10.
The first and second partial segments 11a and llb of
reaction section 11 axe arranged side by side, and in the
shape of an arc at the front end 14 of reaction chamber
10. ~At the rear end 15, in other words at the opposite
end of reaction section 11, entrance and exit doors 16
and 17 are provided. A guide rail 18 of the conveyor
system runs through the reaction section, along which
rail gas-permeable baskets 19 can be moved. In the
vicinity of loading and unloading station 30, guide rail
18 is in the shape of~an arc. Individual baskets 19
always remain engaged with enclosed guide rail 18
(Figures 1 and 3) and are moved continuously in a
circular fashion past individual stations, which include
loading items into the baskets 19 at the loading and
unloading station 30, decontamination in reaction chamber
10, and unloading of the baskets at loading and unloading
station 30.
.. '
The following describes the individual worksteps
(Figure 3):
a) First, a basket (19b, for example) is moved
from first partial segment lla along the curved
section located at end 14 to second partial
segment 11b.
b) Then the row of baskets located in first
partial segment lla is advanced one place to
create an empty place behind entrance door 16.
c) The entrance door 16 opens to admit another
basket (19a in the example), which is filled
with objects to be decontaminated, into the
empty place previously created in first partial
segment 11a.
d) During loading and unloading, the baskets are
advanced one place at laading and unloading
station 30.
e) Then basket 19c located at the end of reaction
section 11 can be guided through exit door l7
to loading and unloading station 30.
f) The row of baskets located in second partial
segment llb is then advanced one place.
The above steps a) to f) are then repeated. The
conveyor system for the baskets is coupled to the SPS
control, so that these worksteps are automated.
Baskets 19 located inside reaction chamber 10 are
exposed to a hot gas mixture provided by a gas supply and
exhaust system (not shown) via feeds 41 (Figures 5-7),
_g_
2I17~3~
which generates a lengthwise gas flow and a transverse
gas flow within reaction section 11, as described below.
Feeds 41 (shown schematically in Figures 5-7)
connected to the gas generator (not shown) feed the
lengthwise gas flow (Figures 2, 3 and 5) in rear end 15
of reaction chamber 10 in both partial segments 11a and
11b. An exhaust blower 42 (Figures 2 and 3) is located
a.t front end 14, which generates a vacuum to draw the hot
gas mixture away and blow it into the open. A lengthwise
gas flow is thus generated in both partial segments 11a
and 11b (Figures 2, 3 and 5) of reaction section 11, said
flow running in the same direction as the conveyor
direction of baskets 19 in first partial segment 11a and
in the opposite direction in second partial segment 11b.
In addition, the vacuum in reaction chamber 11 ensures
that when doors 16 and 17 are opened and closed during
loading and unloading, no possibly contaminated gases can
escape.
As for transverse gas flow 50 (Figures 1 and 4), a
plurality of transverse-flow blowers 51 (Figures 1, 2,
and 4) are mounted on the roof of the reaction chamber,
each driven by a diesel unit 52 (Figure 2). Each
transverse-flow blower 51 (Figure 4) blows the gas
mixture through an exhaust screen 53 (Figures 1 and 4)
located on one of the two side walls of each reaction
section. Screen 53 serves as a gas guiding element in
order to ventilate baskets 19 as uniformly as possible.
The hot gas mixture flows laterally, transversely with
_g_
respect to the conveying'direction, through the baskets
and then is drawn off by transverse flow blower 51.
Because of the good ventilation of the objects to be
decontaminated by the hot gas mixture, rapid heat
transfer is achieved and hence rapid destruction of the
biological or chemical contaminates. In addition, the
transverse gas flow in the circuit results in a high
degree of utilization of the hot gas mixture..
Figures 5, 6 and 7 are schematic diagrams showing
the relationships between the path of the reaction
section within the reaction chamber and the lengthwise
gas flow. While Figure 5 corresponds to the previous
embodiment, Figures 6 and 7 each show an alternative
embodiment. Their versions will be compared with one
another in the following.
Figure 5 represents the embodiment discussed earlier
in which:
a) the reaction section consists of two partial
segments lla and llb located side by side, and
sequentially along the path of the conveyor
guide rail 18;
b) each partial segment lla and llb is provided at
the rear end 15 of the reaction chamber with a
feed 41 for the hot gas mixture;
c) exhaust blower 42 is mounted on front end 14;
d) because of b) and c) above, in each partial
segment lla and llb a lengthwise gas flow 40
causes a flow that moves in the same direction
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as conveyor direction 12 for the baskets in
first partial segment lla and in the opposite
direction in second partial segment 11b.
In contrast to the previous embodiment, the version
shown in Figure 6 shows that
- ' the hot gas mixture is supplied only at the
back end of reaction section 11, through feed
41;
- suction blower 42 is mounted at the beginning
of reaction section 11;
- lengthwise gas flow 40 extends over nearly all
of reaction section 11 (except far a short
portion at the entrance door) in a direction 12
opposite to that in which the baskets are
conveyed.
A disadvantage of the above embodiment is that:
- the temperature of the hot gas mixture
decreases as the distance traveled by the gases
along reaction section 11 increases, because of
heat losses, resulting in a deterioration of
decontamination efficiency.
In contrast, Figure 7 shows that:
- two reaction sections 11' and 11" are provided
to permit parallel operation;
- lengthwise gas flow 40 through the entire
reaction sections 11' and 11" is directed
counter to direction 12 in which the baskets
are conveyed.
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In this third design, the baskets must be returned
along an additional path to the beginning of reaction
sections 11' and 11".
The embodiment of the reaction chamber 10, shown in
Figure 1, is also designed for nuclear decontamination.
For this purpose, in a first section of reaction section
11, nozzles for spraying decontamination solution are
provided on a spray rack in a conventional manner. In a
subsequent section of reaction section 11, spray racks
are likewise provided with nozzles for washing off the
decontamination solution with a rinsing solution (water
for example?. In a final secti0ll of reaction section 11,
blowers are provided for drying with hot air. The
decontamination and rinsing solutions are supplied
through an external connection. To achieve a high degree
of decontamination,.each set of clothing and equipment
items is distributed between two baskets 19. The
operation for nuclear decontamination, like biological
and chemical decontamination, is supported by the SPS
control system and is therefore automated.
Although the invention has been described and
illustrated in detail, it is to be clearly understood
that the same is by way of illustration and example, and
is not to be taken by way of limitation. The spirit and
scope of the present invention are to be limited only by
the terms of the appended claims.
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