Note: Descriptions are shown in the official language in which they were submitted.
METHOD AND APPARATUS FOR DEODORIZATION OF CORK
BACKGROUND OF THE INVENTION
The present invention relates to removing offensive
odors from cork. Specifically, the present invention relates to
removing 2,4,6-trichloroanisole (TCA) which has a charac
l0 teristic odor.
Descr~tion of the Background Art
Cork has unique characteristics. It is lightweight
and has a high degree of resilience. Additionally, it has
excellent gas and liquid sealing properties, and has stability
against solvents such as alcohol. Furthermore, it is a hygienic
material which is food-safe and not harmful to human beings,
and has no intrinsic odor.
20 Because of the above mentioned characteristics, cork
has been widely utilized as stoppers for casings such as
bottles filled with liquor such as wine, brandy or whiskey, or
casings packed with various kinds of foods.
However, in spite of having no intrinsic odor,
offensive odor is encountered on cork stoppers on rare
occasions. This odor, when present, deteriorates the quality of
the contents of the bottles or casings sealed by the cork.
Recently by various studies, 2,4,6-trichloroanisole (TCA) has
been identified as the substance which originates the offensive
30 odor. TCA is considered as the substance produced by moulds
from 2,4,6-trichlorophenol (TCP) which is utilized in agents
conventionally used to spray cork oak. Also, in "Journal of
Agricultural and Food Chemistry", (1982) pages 359 to 362,
presumption is given that 2,4,6-trichlorophenol and other
related chlorinated compounds originate from chlorination of a
liquid-related substance during the chlorinate bleaching used
2
in the processing of the cork and that these compounds are
later extracted into the liquor, such as wine. Similar
consideration that a chlorinate agent is the source of the odor
substance has been given in "Science des Aliments" (1984),
pages 81 to 93. In the discussion, it has been pointed out that
the 2,4,6-trichloroanisol is derived from pentachlorophenol or
other chlorinated pesticides applied to the tree. Further
consideration is given that cork material and corks stored in
premises with an atmosphere polluted by chloroanisoles may
l0 contaminate bottled wine aged in healthy cellars.
Methods for effective deodorization of cork have been
studied, and the following methods have been attempted.
(1) Dry-heating deodorization
Cork is heated and dried at 80°C for 6 to 8 hours,
after which the offensive odor causing substances are
substantially evaporated. However, TCA is specifically adsorbed
by the macromolecular compounds which form cork such as
cellulose, lignin and suberin, and it is difficult to remove
TCA in the dried state. The boiling point of TCA is 240°C at
20 738.2 mmHg, and 132°C at 28 mmHg. Therefore, in order to
evaporate TCA, a heating temperature must be applied which is
higher than the boiling point of TCA. However, it is difficult
to raise the internal temperature of cork without heating the
surface excessively, which results in deterioration of cork's
desirable characteristics. As such, heating is applied only to
the surface of the cork, therefore TCA in the interior cannot
be removed entirely.
(2) Repetition heating deodorization
Cork is heated at 80°C for 6 hours, and is then left
30 at room temperatures for about a month. TCA can be removed by
repeating this treatment many times. However, this method
requires long periods of treatment until the TCA is entirely
removed; therefore, production efficiency is low. For example
2 or 3 repetitions of the above treatment are insufficient for
entirely removing TCA.
,,.,
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(3) Citric acid deodorization
Cork is deodorized by being soaked in a 3~ vol
solution of citric acid for 3 to 5 min. However, the effects of
this deodorization technique are retained only for a short
period. That is because, as cork resists absorption of liquids,
the citric acid solution cannot reach the cork interior.
Therefore, since the deodorizing treatment affects only the
cork surface, untreated TCA within the cork is moved to the
cork surface with the elapse of time; thus the offensive odor
re-occurs.
(4) Oxidant bath deodorization
Cork is deodorized and sterilized by soaking in a 1~
vol solution of hydroperoxide (H202). However similar problems
are caused as in the case of citric acid deodorization.
(5) Alcohol steam deodorization
Cork is left and deodorized in an alcohol atmosphere
at 18 to 24°C for a month. However, this method encounters the
same problems as methods (3) and (4).
(6) Hot water washing
Cork in the grain state is washed in hot water at a
temperature of 60°C. The treatment needs to be repeated 2
times. But, as TCA has a relatively strong affinity for cork,
it is moved to and retained in the internal portions of the
cork. According to this method, therefore, the deodorizing
effect is still insufficient because the treatment affects only
the cork surface.
(7) Soxhlet extraction
TCA in the cork is extracted by a Soxhlet extractor
at 45°C for 24 hours with n-pentane. By this method, TCA is
entirely removed from both the surface and internal areas of
the cork. However, the equipment is very expensive and
production costs become very high. Furthermore, a certain
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degree of safety risk is encountered with this method.
(8) Dispersion
It has been considered to simply grind the cork into
grains having a certain diameter, and then form it back into
the desired form by pressing with adhesives. However, since TCA
~is merely dispersed in each grain, high improvement cannot be
expected from this approach.
(9) Sterilization with Irradiation
"Deutsche Lebensmittel-Rundschau" (1984) Pages 204-
207, is directed to sterilization with irradiation. There, the
mechanism of formation of cork taint in wines is discussed. The
use of an irradiation process has been proposed for preventing
microbial conversion from TCP to TCA, thus achieving prevention
of cork taint. However, this method cannot remove TCA residing
within the internal structure of the cork.
(l0) Sterilization with Ozone
German Patent First Publication No. 34 05 422
discusses that cork is sterilized with ozonized water on an
ozonized silicone emulsion, in which the ozonized concentration
is P1 mg/Q at a temperature lower than 30°C.
However, this method encounters the same problems as
methods (3) and (4).
SUMMARY OF THE INVENTION
It is therefore the principal object of the present
invention to provide a method for deodorizing cork by removing
a substance causing offensive odors, principally TCA from the
cork interior.
It is another object of the present invention to
provide a method for deodorization of cork without
deteriorating the cork's unique characteristics.
It is a further object of the present invention to
provide an apparatus for simply and inexpensively deodorizing
the cork.
The present invention provides a method for removing a
substance which is contained in cork and which originates an
offensive odor, said method comprising the steps of:
a) putting cork into a container;
b) heating water to generate steam flow of a given
temperature;
c) supplying the generated steam flow to said
container;
d) controlling steam flow pressure and temperature
within said container at a predetermined pressure and
temperature below an upper limit, which results in preventing
degradation of cork properties, and above a lower limit,
which results in promoting penetration of said steam flow
into the internal structure of the cork, so as to promote
evaporation of said substance which originates an offensive
odor; and
e) discharging said steam flow along with the evaporated
substance from said container.
According to one aspect of the invention, a method for
deodorization of cork comprises the step of applying steam to
the cork to remove a substance originating offensive odor in
the cork, wherein temperature and pressure of steam for
deodorization treatment are so selected as to penetrate steam
molecules into the internal structure of cork.
According to another aspect of the invention, a method
for removing a substance originating an offensive odor in the
cork comprises the steps of:
- a first step of putting the cork into a container,
- a second step of supplying steam to the container for
generating steam flow at a given temperature and a given
pressure, the temperature and pressure being selected for
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penetrating steam molecules into an internal structure of the
cork and promoting steam volatilization within the internal
structure of the cork,
_ _ - _ . _ ~ . v v _ _ -L 1L- _._~7_
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and containing the substance originating offensive odor, from
the container.
The substance originating offensive odor may be
2,4,6-trichloroanisole and the 2,4,6-trichlorophenol.
The method further comprises the steps of:
- cutting the cork into pieces having a predetermined
size,
- pre-heating the cut cork to a certain temperature,
and
- maintaining the temperature and the pressure during
deodorization.
In such case, the steam temperature is at least
100°C; and the system pressure is at least 760 mmHg. In the
preferred embodiment, the second step further comprises
supplying the steam for the cork from the bottom of the
container. The second step may further comprise agitating the
container. In such case, the agitating step is comprised of
rotating and/or oscillating the container. The agitating step
may comprise a step of stirring the cork in the container.
The method may further comprise a step of cooling the
cork in the container. The cooling step may include the steps
of
- generating a hot air; and
- supplying the hot air to the interior of the
container while maintaining rotation and oscillation of the
container.
Preferably, the step of supplying the air is
performed after natural cooling and at a timing where cooling
efficiency by natural cooling is lowered.
According to a further aspect of the invention, an
apparatus for deodorization of cork by steam comprises:
- means for generating a flow of steam at a given
temperature and a given pressure which are selected for
purifying cork by causing steam to penetrate within the
internal structure of the cork to remove a substance
originating an offensive odor contained in the cork.
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According to another aspect of the invention, an
apparatus for removing a substance which is contained in cork
and which originates an offensive odor, comprises:
- a container means defining an internal space for
receiving a cork piece therein, said container means having an
inlet and an outlet;
- a steam generator for generating steam flow of a
given temperature to supply said generated steam flow to said
container means through the inlet thereof;
- pressure control means for controlling pressure
within said container means at a predetermined pressure
required to promote penetration of said steam flow into the
internal structure of said cork piece so as to promote
evaporation of said substance;
- agitating means for agitating said cork piece in
said container means, said agitating means including rotating
means for rotating said container means around a rotation axis
and oscillating means for causing said container means to
oscillate around an oscillation axis which is essentially
perpendicular to said rotation axis of said container means;
and
- discharging means for discharging the steam flow
along with the evaporated substance from said container means
through said outlet.
According to a still further aspect of the invention,
an apparatus for deodorization of cork comprises:
- first means for containing the cork,
- second means for supplying steam from a steam
generator for forming a steam flow from an inlet to an outlet
of the first means, the steam in the steam flow being
maintained at a given temperature and a given pressure selected
for removing a substance causing offensive odor from the cork,
- third means for discharging the steam along with
the substance causing offensive odor through the outlet of the
first means.
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The present invention will be understood more clearly
from the preferred embodiments described herebelow and from the
appended drawings which illustrate the detailed composition of
the embodiments, which, however, should not be taken to limit
the invention but are for explanation and understanding only.
In the drawings:
Fig. 1 is a block diagram showing a method for
l0 removing offensive odor substances according to the present
invention;
Fig. 2 is a sectional view of an apparatus for
deodorization of cork according to the present invention;
Fig. 3 is a graph showing a relationship between a
total amount of supplied steam and TCA removal ratio; and
Fig. 4 is a graph showing the relationship between
penetration of steam and the temperature and pressure of the
steam.
20 DETAILED DESCRIPTION OF THE INVENTION
The present invention is accomplished by utilizing
conventional steam volatilization.
As is well known, the cork has a water resistive
property to prevent water molecules from penetrating into the
internal structure thereof. Therefore, though it is known that
TCA on the surface of the cork can be washed out by water,
internally contained TCA cannot be removed by water. To this
point, it has been known that TCA has a characteristic which is
30 that it can volatilize with steam. Additionally, it has a
relatively low boiling point at 28 mmHg. Therefore, if treating
temperatures are controlled at the level at which the partial
pressure of TCA becomes 28 mmHg, TCA can be evaporated at
relatively low temperatures. Taking the factors mentioned above
into consideration, the inventors became aware that steam
volatilisation may be effectively utilized for the
9
deodorization of cork. Previously, steam volatilization had
never been applied for cork deodorization. In various attempts
made by the inventors, it has become apparent to the inventors
that steam temperature and pressure are very important factors
for enabling steam volatilization. Particularly, according to
the invention, the steam is enabled to penetrate into the
internal structure of the cork for heating the internal
structure so that steam volatilization is caused within the
internal structure for removing TCA residing inside of the
cork.
It is considered that molecules of steam can be
excited for increased mobility under a given temperature. Such
increased mobility of steam molecules is enabled to
successfully penetrate into the internal structure of the cork.
The steam molecules penetrated into the internal structure of
cork heat the inside of cork to the temperature at which steam
volatilization is internally caused. By this, TCA contained in
the internal structure of the cork can be evaporated.
Any kind of cork may be used and is not limited by
the field of use to which it is put nor by its form. For
example, cork for bottle capping, wine bottle stoppers or crown
disks, for architectural use, vibration proofing or heat
insulator materials may all benefit from treatment according to
the present invention.
The shape of the container is not limited
specifically, but for effective steam utilization, a
longitudinal shape for the container which is formed with a
diameter smaller than its height is most preferred.
Any state of cork is acceptable, but for enhancing
the removal efficiency by homogenizing steam and cork,
maintaining the cork in an agitated state while supplying steam
to the container is preferable. For agitating, to move the
container per se (e.g., by oscillating or rolling) or to
locate an agitating means in the container to stir the inner
materials are both acceptable.
In general, the steam temperature should be at least
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100°C, and, the pressure of the container should be at least
760 mmHg. When the steam temperature is lower than loo°C, the
partial pressure cannot be high enough to cause steam
volatilization within the internal organization of the cork.
Also at the temperature lower than 10o°C, penetration of steam
molecules into the internal structure of cork may not be
sufficient. On the 'other hand, when the steam temperature is
higher than 130°C, difficulty is encountered in controlling
temperature during cooling process. That is, at high steam
temperature, a significant amount of steam can penetrate within
the internal structure. The steam that penetrates within the
internal structure of the cork may lead to shrinking of the
cork when it is subjected to atmospheric temperature as a
result of rapid cooling. A significant magnitude of cork
shrinkage may degrade the cork properties. Therefore, the
temperature is preferably maintained lower than or equal to
130°C.
Cork size is not limited specifically, but a smaller
size is preferred because TCA movement from within the cork to
its surface becomes easier. This results in an effective
removal of TCA.
It should be appreciated that the treatment
temperature, the system pressure, the container configuration,
cork amount to be treated, and other conditions for steam
volatilization treatment can be selected according to required
efficiency and degree of removal of TCA.
According to the above identified steam
volatilization, the partial pressure of TCA can be reduced by
the partial pressure of steam, then the boiling point of TCA
3o can be lowered at around atmospheric pressure. Therefore,
deterioration of cork can be avoided and deodorization of cork
by removal of TCA can be accomplished sufficiently.
A method for removing offensive odor in the cork
according to the present invention is described in detail
referring to the appended Figures which show the processing
system for TCA removal.
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Referring now to Fig. 1, a block diagram showing the
method for removing offensive odor according to the present
invention is shown. A given amount of cork 2 cut to a
predetermined size is put into a treating container 1. Purified
water provided from a purified water generator 4 is supplied to
a steam generator 3. Then, after steam is generated in the
generator 3, it is supplied to the container 1 via a steam
supply pipe 5. Steam volatilization of the cork 2 is performed
in the container 1, then steam is discharged from the container
l0 1 through a steam discharge pipe 6 out of the system. Steam
feeding is controlled by a supply valve 7, a flow meter 8,
pressure meters 9 and l0, a discharge valve 11, and a flow
control valve 12. Temperature sensors 13, 14 and 15 are
installed in upper, middle and lower parts of container 1,
respectively. The temperature in the container 1 is monitored
through these sensors by a monitor system 16, then temperature
is controlled at the constant predetermined level.
The container 1 has an outer container 17 and an
inner container 18 spaced from the outer container 17 at a
2o constant interval as shown in Fig. 2. It may be formed as a
cylinder. In this way, the container 1 is formed as a pressure
proof container having a double-walled structure. This
structure enables steam to be introduced into the space between
the outer and the inner wall after it goes through the cork 2.
Therefore, steam in the space through which the steam past the
cork flows, serves for maintaining the container temperature at
the desired treatment temperature and thus for reducing the
heat loss in the steam.
Referring now to Fig. 2, when amounts of cork 2 are
30 put into the inner container 18 by opening a lid 19, they pile
on a bottom plate 20. Steam is sprayed into the interior of the
container 1 through a plurality of steam pores 21 penetrating
the bottom plate 20, and runs through the piled cork 2 from
bottom to top.
A steam inlet pipe 22 is connected to the center port
of the container's bottom and extends from the lower end of the
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outer container 17 of the container 1 to the outside of the
container. The lower edge of the inlet pipe 22 is connected to
the steam supply pipe 5 via a first rotary joint 23. Steam
fluid supplied from the supply pipe 5 is supplied to the inlet
pipe 22, to the inner container 18 via the steam spraying pores
21 in the bottom plate 20 of the container 1. Then, steam
supplied into the inner container 18 rises through the cork 2
concurrently heating it, and is discharged from steam
discharging pores 24 which penetrate the upper side walls) of
the inner container 18 into the space 25 between the outer
container 17 and the inner container 18 and an outlet pipe 26
coaxially arranged surrounding the outside of the steam inlet
pipe 22. Then, it is discharged from the steam discharge pipe
6 connected to the outlet pipe 26 via a second rotary joint 27.
Pressure and flow of steam can be controlled at a constant
level by the discharge valve 11 and the flow control valve 12.
In order to homogenize sprayed steam and the cork 2,
agitating the material in the container 1 is effective. A
central shaft 28 for rotation is located surrounding the outlet
pipe 26, and is rotatably supported by a bottom portion 30a of
an oscillating frame 30 formed in a U-shape via a bearing 29.
The container 1 can be rotated against the central shaft 28 by
a rotation drive device 31 installed on the bottom portion 30a
of the oscillating frame 30 composed of a motor, rotation gear,
translation gear or so forth. Additionally, the container 1 can
be oscillated by the oscillating frame 30. Then, by rotating
with oscillation, the cork 2 and steam in the container 1 can
be agitated sufficiently. A pair of supporting shafts 32 and 33
are installed to an outer surface of an upper end of the side
portions Sob of the oscillating frame 30. These shafts 32, 33
are oscillatably supported by a pair of fixed frames 36, 37 via
bearings 34, 35 to be oscillated by an oscillation drive device
38.
The oscillation drive device 38 is composed of a worm
wheel 39 installed on the supporting shaft 33 and a motor 42
which rotatably operates a worm gear 40 via a belt 41, where
13
the worm gear 40 is engaged to gear teeth of the worm wheel 39.
When the motor 42 is rotated in one direction, the worm gear 40
and the worm wheel 39 are rotated in order. This rotation
slowly oscillates the oscillating frame 30 in one direction. On
the other hand, when the motor 42 is rotated in the other
direction, it slowly rotates the oscillating frame 30 in the
other direction. In this way, the oscillating frame 30 is
oscillated.
In order to supply steam regardless of oscillation of
l0 the oscillating frame 30, the steam supply pipe 5 is located
through the center portion of the supporting shaft 33,
connected to the oscillating frame 3o via a third rotary joint
43, and further connected to the container 1 via the first
rotary joint 23. The steam discharge pipe 6 is located through
the center portion of the other supporting shaft 32, connected
to the oscillating frame 30 via a fourth rotary joint 44, and
further connected to the container 1 via the second rotary
joint 27.
A slip ring 45 is mounted on the edge of the central
20 shaft 28 of the container 1. Signals, obtained from temperature
sensors 13, 14 and 15, connected to the outside portion of the
oscillating frame 30 via the slip ring 45, are input to a
monitoring device 16 which is connected to the slip ring 45 (as
shown in Fig. 1) allowing the temperature in the container to
be effectively monitored.
Circular frames 46 are mounted on the top of the side
portion Sob of the oscillating frame 30. Rollers 47 are
installed in the inner surface of the radial frames 46 to
rotate the container 1 smoothly by supporting the outer
30 surface of the upper part of the container 1.
In the shown embodiment, rotation speed of the
container is preferably determined at, at least, l0 rpm, and
the incline angle is preferably determined as at least ~ 60°,
though they depend on conditions such as the processing amount
and cork size. The inclination angle range of the container is
not strictly limited to ~ 60° but can be selected in any way.
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14
In general, the inclination angle of the container may be
determined according to the degree of filling of the cork
within the interior space of the container. Namely, the
inclination angle is so selected that the cork can be
distributed over an entire area of the steam path so that steam
cannot escape without contacting with the cork. Similarly, in
case of rolling or agitation, care should be given so that blow
off of the steam may not be caused. Therefore, driving speed in
rolling and agitation may be determined according to the amount
l0 of the cork filled in the container.
Further to say, there is no problem processing by
steam volatilization in a stationary environment (not rotated
or oscillated).
In order to avoid physically changing the cork, for
example by shrinking, it may be preferable to cool the cork
slowly while maintaining the cork within the container 1
because the volume of cork becomes smaller or the cork shrinks
when it is subject to substantially low temperature after
penetration of steam of relatively high temperature.
20 Particularly, since the temperature of the internal structure
of cork cannot be cooled as fast as that on the surface,
relatively long period is required for satisfactorily cooling
the internal structure of the cork. This means that if they are
removed from the container immediately to the subject
atmosphere, a substantial magnitude of shrinking may be caused
in the cork to make it stiff to degrade the cork property. On
the other hand, allowing natural cooling takes a very long
time. Therefore, supplying a hot atmosphere to the container by
way of cooling may be effective. Here, rotation and oscillation
3o of the container 1 are continued while cooling. During natural
cooling, it has been observed that cooling efficiency is
significantly dropped at a certain temperature. In order to
accelerate cooling, the hot atmosphere is generated in a hot
atmosphere generator (not shown in the Figures), and is
supplied to the container 1 by controlling the valve 7 located
on the steam inlet side. As the cork 2 is wetted by steam, hot
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atmosphere supplied to the container 1 can take latent heat
from the surface of the cork 2 when steam is evaporated. This
increases the cooling speed. The results of cooling tests on
the cork are shown in the following Table 1.
Repetition 1 2 3 4 5
Cooling periods (min.) 47 48 47 50 46
Volume ratio (~) 111.4 98.0 95.0 96.4 104.7
Volume ratio (~); dried weight after treatment
dried weight before treatment
Materials are shrunken when this value exceeds 100.
Treatment indicates steam volatilization.
Test conditions:
Flow amount of steam . 280 1/hr.
Period of treatment . 64 min.
Pressure (cage pressure): 1 kg/cm.
As shown in Table 1, shrinking of the cork was
prevented.
In order to demonstrate the advantages accomplished
by the present invention, experiments (were performed. In the
experiments, natural cork of the size io cm x l0 cm x 5 cm is
heated in an autoclave for 60 minutes at respective
temperatures of loo°C, 110°C, 12o°C and 13o°C. The
pressures at
respective temperatures are shown in the following Table 2.
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Temperature (C) Pressure (Kg/cm2)
100 1.033
110 1.461
120 2.055
130 2.754
For checking depth or degree of penetration of steam
into the internal structure of the cork, the cork piece samples
were cut by a knife and the penetration dimension from the cork
surface was measured. The result of measurement is shown in the
following Table 3 and Fig. 3.
Temperature (C) Penetration Magnitude (mm)
100 0.5
110 5.0
120 10.0
130 20.0
As can be seen from the foregoing Table 3 and Fig. 3,
the penetration degree is exponentially increased according to
rising of the steam temperature.
A cork capping plug recognized as corked was crushed
by a known cork crushing machine into a grain size ordinarily
used for forming compressed cork, for forming sample cork
pieces. 4 g of the sample cork pieces were put in a gauze bag
(15 cm x 20 cm). The sample cork containing bag is put in the
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mid portion of the cork burden in the container 1.
Deodorization treatment was performed utilizing the apparatus
of Fig. 2. In the treatment, the container 1 was rolled with
successive variation of inclination angle. The steam was blown
through the container 1 across the cork at a flow rate of 20
liter/hour and 40 liter/hour. The deodorization treatment was
performed for 30 minutes, 60 minutes and 90 minutes after
reaching a predetermined condition, i.e. the temperature in the
container was 120°C and pressure was 1 kg/cm2. After treatment,
l0 residual TCA amount was checked. Check of residual TCA was
performed by slicing the sample cork, extracting TCA from
slices by n-pentane, and measuring by gas cromatography.
Results of measurement are shown in Table 4 and Fig. 4.
Steam Flow Rate Steam Flow Rate
20 1 hr 40 1 hr
25,25,18,22,24,28,19,30, 5,4,6,6,5,6,8,6,5
20 32,32
(ng/g) (ng/g)
30 min Average Standard 25.5 Average Standard 5.3
Error 4.99 Error 1.77
CV($) 22.8 ~ CV($) 33.4
Removal 89.7 ~ Removal 97.8 ~
7,8,8,11,9,13,12,13,13,12 1.5,1.3,1.6,2.8.2.8,
1.6,1.7,2.7,1.5,3.0
(ng/g) (ng/g)
60 min Average Standard 10.5 Average Standard 2.1
Error 2.51 Error 0.68
CV(~) 23.9 ~ CV(~) 32.4 g
Removal 95.7 Removal 99.1
7,9,8,7,8,8,10,7,9,10
(ng/g)
Average Standard 8.3 Average ND
30 90 min Error 1.16
CV(~) 14.0 $
Removal 96.6 Removal 100
As can be appreciated, the present invention is
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successful in achieving the object and advantages sought
therefor.
While the present invention has been disclosed in
terms of the preferred embodiment in order to facilitate better
understanding of the invention, it should be appreciated that
the invention can be embodied in various ways without departing
from the principle of the invention. Therefore, the invention
should be understood to include all possible embodiments and
modifications to the shown embodiments which can be embodied
to without departing from the principle of the invention set out
in the appended claims.
