Note: Descriptions are shown in the official language in which they were submitted.
9776
This invention relates to a method and apparatus
for separating constituent gases from a gaseous mixture by
the utilization of the difference in their ratios of specif~c
heat i.e. Cp/Cv, hereinafter referred to as the ratio K.
It is known in the art that a gaseous mixture can
be separated into its constituents by utilizing the difference
in their speeds of diffusion, their thermal diffusion rates
or, alternatively, their relative densities e.g. by utilizing
centrifugal force. The most suitable method is selected by
taking into consideration the nature of the gases in the
mixture, the purpose of the separation, the expected efficiency
and the cost. However, these methods have the common disad-
vantages of low separation efficiency and a rélatively long -
operation time.
Against this background, the inventor of the present
invention has discovered that when a mixture of gases having
different ratios of specific heat is ejected in a potentially
expansive (underexpansion) state at a supersonic speed through
a divergent nozzle, the constituent gases tend to deflect at
angles characteristic of their ratios of specific heat. Based
upon this discovery and theory, the present invention embodies
methods and apparatus for use in separating a gaseous mixture
to obtain the constituent gases individually on an industrial
scale.
According to one aspect of the invention there is
provided a method of separating a gaseous mixture consisting
of gases having different ratios of specific heat into the
constituent gases, comprising ejecting said gaseous mixture
at supersonic speed through a divergent nozzle capable of
operating wlth a gas in a potentially expansive state and
allowing said gaseous mixture to separate into the constituent
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gases inside and outside a separator screen spaced from the
outlet of said nozzle and inside the maximum deflection angle
with respect to said constituent gases.
According to another aspect of the invention there
is provided an apparatus of separating a gaseous mixture into
the constituent gases, comprising a furnace for subjecting a
material to heat, a divergent nozzle capable of operating with
a gaseous mixture in a potentially expansive state, a gas
ejecting pipe for allowing a gas produced in said furnace to
reach said nbzzle, and a separator screen spaced from said
nozzle outlet and located inside the maximum deflection angle
with respect to said constituent gases.
Very briefly, the discovery upon which the invention
is based was made when heated vapors of Ca and CO, and of Mg
and CO were tested for their adiabatic expansion during
passage through a divergent nozzle. When a gaseous mixture
of Ca and CO is ejected at a supersonic speed through a divergent
nozzle under the condition at which the gas is in a potentially
expansive state inside the nozzle against the external pressure,
the e~ected gas tends to expand at the nozzle exit and deflects
at a wider angle than that of the inside walls of the nozzle.
In this case, it was found that the CO gas deflects more than
the Ca gas. This may not at first appear to be a surprising
fact, bécause the relative density of Ca is greater than that
of CO at the nozzle exit. According to conventional theory,
it will be accepted as a matter of course that the lighter CO
tends to deflect more than the heavier Ca. On the other hand,
when a gaseous mixture of Mg and CO was ejected in the same
manner, the constituent gases expanded at the nozzle exit, but
the CO gas deflected more widely than the Mg gas, irrespective
of the fact that the relative density of CO is greater than
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897~6
that of Mg. This test demonstrated that the heavier C0
tends to deflect more than the lighter Mg which, according to
the conventional theory, contradicts the facts found in the
first test using Ca and C0.
To ensure accurate tests by avoiding any unfavorable
influences due to the condensation of metal vapors, the Mg and
Ca gases were ejected through the nozzle as superheated vapors,
but the same results indicated above were obtained. Thus, the
tests show that the deflection of an e~ected gas is independent
of its relative density.
It has long been known that a heavier object tends
to position itself inside a lighter object: however, this
theory cannot explain the results of these experiments. Through
repeated tests the inventor has found that the deflection of
an ejected gas depends upon its ratio of specific heat K, and
that this holds true even when two or more gases with different
ratios are mixed together. It has also been demonstrated that
a gas having a smaller ratio tends to deflect at a greater angle.
Preferred embodiments of the invention will be more
particularly described in the following disclosure with
reference to the drawings, in which:
FIGURE 1 is a chart showing the principle of an
expansion flow around a solid corner at a supersonic speed;
FIGURE 2 is a similar chart showing the principle
of an expansion flow in which a pressure curtain is employed
~, instead of the solid wall of FIGURE l;
FIGURE 3 is a cross-sectional diagrammatic view
showing a divergent nozzle through which a gas is ejected at
a supersonic speed in a potentially expansive state;
FIGURES 4 to 6 show an arrangement of divergent nozzles
and separator screens in cross-sectional diagrammatic form;
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1~89~76
FIGURE 7 is a vertical cross-section through one
embodiment of the apparatus of the present invention.
Referring to FIGURE 1, a jet of a gaseous mixture
in the form of a stream flows along the outwardly curved wall
AOB at a supersonic speed. The stream changes its speed and
direction at the point 0, thereby becoming a uniform stream
parallel to the wall OB. This is known as a Prandtle-Meyer
expansion stream:
~=f(M,A)=Atan (A ~-l)-tan ~ (1)
wherein:
A = ~ Y. = Cp/Cv M ... Mach number
g 2 1 (M2~A~ f(Ml,A) (2)
wherein:
M2 > Ml > 1
Ml... The Mach number up-stream
M2... The Mach number down-stream
As shown in FIGURE 2, the wall OB can be replaced by
a pressure curtain OB' against the external pressure P. When
the pressure at the nozzle inlet is PO and the pressure at
the nozzle outlet is Pl,
',:
2 ) (3) ~ -
~ ) 2 2
! o ( K - 1 ) Ml + 2
In general, when a gaseous mixture is ejected at a
supersonic speed through a nozzle, it will be possible to
determine the speed and amount of the ejection and the tem-
perature at the nozzle outlet from its attributive numbers,
if they are known. If a calculation is made on the assumption
that each constituent gas is separately ejected through a
. ~ .
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1~89~7!t~
nozzle under the same conditions of temperature at the nozzle
inlet and attributive partial pressure of the gaseous mixture
at the nozzle inlet and outlet, it follows, as is generally
known, that the total amount of the ejection of the constituent
gases is in accord with the amount of the ejection of the
gaseous mixture, and that the average values of temperature
and speed of the constituent gases at the nozzle outlet are
respectively in accord with the values of temperature and -
speed of the gaseous mixture. If the temperature of the nozzle
inlet is constant, the deflection angle ~ of each constituent
gas can be obtained by putting the values of its ratio of
specific heat and partial pressure into equations (1), (2) and
(3). This calculated angle means that the constituent gas
deflects at this angle if it is separately ejected through
the nozzle at the same temperature at the nozzle inlet as for
the gaseous mixture and at the same partial pressure thereof.
In this case P0, Pl and P are the values of partial pressure
with respect to the constituent gases. If there are two
constituent gases Gl and G2 having ratios Kl and K2, and each
constituent gas is separately ejected under the conditions
mentioned above, i.e. at the same temperature at the nozzle
inlet as for their gaseous mixture and at the same partial
pressure thereof, the values of the deflection angles ~l and
~2 will be obtained, wherein each value corresponds to its
ratio Kl and K2. If these gases are mixed and ejected at a
supersonic speed through a divergent nozzle, wherein it is
required to maintain the gaseous mixture in a potentially
expansive (underexpansion) state, at the same temperature at
the nozzle inlet but at normal pressure (the sum of the partial
pressure values with respect to the constituent gases), the
constituent gases will deflect at angles ~1 and ~2 that would
1(~8~177~i
be obtained if each constituent gas were singly ejected. The
present invention thus aims at utilizing the difference in
deflection angles between the constituent gases.
In order to ensure that the constituent gases of a
gaseous mixture deflect at their proper angles when the mixture
is ejected at a supersonic speed through a nozzle, the nozzle
should be of the divergent type capable of operating with the
gas in a potentially expansive state. Examples are illustrated
in FIGURES 3 to 6. Various cross-sections can be employed,
such as circular, elliptical, triangular, rectangular, polygonal.
When the cross-section is rectangular, two opposite side walls
may be made to diverge from the axis of the nozzle towards its
exit while the remaining walls may be parallel to the axis.
The divergent nozzle may be an umbrella-type divergent nozzle,
but nozzles of the type operable only with a gas in an optimum
expansion state or in an overexpansion state cannot be employed,
because at the optlmum expansion state Ml will be equal to M2
in the equation (2) as a rule, and no deflection angle will -
occur because ao = o. Strictly speaking, it is admitted that
an appreciable expansion of the gas will be brought about by
inertia at the nozzle outlet, but the gas will immediately
contract. After a repetition of the expansion and contraction
the gas will gradually attenuate. In addition, the expansion
and contraction take place at different locations as time goes
on. Under such changing conditions of flow direction it is
impossible to separate a mixed gas into its constituents.
Llkewise, when the divergent nozzle is operable only
with a gas in the overexpansion state, Ml will be equal to M2,
thereby causing no deflection angle ~. In addition an
undesired peeling is likely to occur inside the nozzle. If
the nozzle is a convergent type, the Mach number at the nozzle
776
outlet will amount to 1 at maximum, and in addition no
deflection angles can be derived from the equation (2). In
this case, however, if the external pressure P is considerably
decreased, an appreciable expansion of gas will take place at
the nozzle exit, but this expansion is unstable and does not
last long, attenuating to a subsonic speed. Thus convergent
nozzles are ineffective for separating a gaseous mixture into
its constituents.
As described in the foregoing, it has been ascertained
by repeated tests that when a gaseous mixture consisting of
gases having different ratios of specific heat is ejected at
supersonic speed through a divergent nozzle in a potentially
expansive state, the constituent gases tend to deflect at the
same angles as those calculable on the assumption that each
constituent gas is separately ejected at the same temperature
at the nozzle inlet as for the gaseous mixture, and at the
same partial pressure thereof. This fact has been ascertained
by calculation as well as by tests.
In general, the ratio of specific heat K is almost
Z0 constant according to the number of atoms in the particles
forming the gas; e.g. a monoatomic gas has a K of about 1.67:
a diatomic molecule gas has a K of about 1.40: a multi-atomic
molecule gas (having more than two atoms~ has a K of no
greater than 1.33. By the present invention it is thus possible
to separate a gaseous mixture into its constituents when the
; mixture consists of a monoatomic gas and a diatomic molecule
gas, or a monoatomic gas and a multi-atomic molecule gas, or
a diatomic molecule gas and a multi-atomic molecule gas.
If the gases to be separated from the mixture are G
and G2 having deflection angles ~l and ~H2 (~2 ~ ~l)' and
the amount of G2 outside the separator screen is X2G2 (X2:
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9~76
proportion of G2 outside the separator screen) while the
amount of Gl inside the separator screen is XlGl (Yl: pro-
portion of Gl inside the separator screen), the following
formulae are obtained:
The amount of G2 outside the separator screen ...
2 2
The amount of Gl outside the separator screen ...
Xl) Gl (5)
The amount of G2 inside the separator screen ...
10 (1 - X2) G2
The amount of Gl inside the separator screen ...
Referring now to FIGURES 4 to 6, the installation
and operation of the separator screen will be explained.
(1) In FIGURE 4, the separator screen 3 is located :
at a position spaced outwardly by ~1 from the extension 2 of
'~ the inside wall of the nozzle 1. This location is expressed by:
~1 + ~/2 :~
wherein ~ is the angle of the screen 3 to the axis of the :~
' 20 nozzle and ~t2 is the angle of the extension 2 of the inside
wall of the nozzle to the axis of the nozzle. For simplifying,
. the explanation this formula will be replaced by:
1 + ~/2
This equation means that the separator screen 3 is
located in line with the deflection angle ~l of the constituent
gas Gl, and in the formulae (5) Xl = 1. Thèrefore:
The amount of G2 outside the separator screen ...
X2G2
The amount of Gl outside the separator screen ... 0
(6) -
The amount of G2 inside the separator screen
(1 - X2) G2 ' '.
The amount of Gl inside-the separator screen ... Gl
.
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It will be understood from the formulae that the
constituent gas Gl is ejected inside the separator screen 3.
This arrangement of the screen can thus be adopted when it
is desired to free the gas G2 from its admixture with Gl.
In this case X2 depends upon the value of L/D, wherein L is
the distance between the nozzle exit and the separator screen
3, and D is the inside diameter of the nozzle opening. An
example of the relationship therebetween is numerically ex-
pressed as follows:
i
¦ X ~ 0 31 ¦ 0 36
",
According to this embodiment, G2 can be separated
without having Gl admixed therewith, which constitutes one
of the advantages over the known methods.
(2) In FIGURE 5 the separator screen 3 is located
~; such that its leading edge is placed on the line of the
deflection angle ~l' and that the equation ~ = ~2 + /2 is
established. This arrangement of the screen allows the same
' separation of a gaseous mixture as under the formula (6).
(3) The separator screen 3 can be. located such that
the formula ~ l + /2 is established. This arrangement is
not shown in the drawing. Under this arrangement the separation
expressed by the formulae (5) will be effected. In this case,
if L/D is constant, the rate of gas flow tends to increase
outside the separator screen, but Gl is likely to mix therewith.
In addition, the value of X2 increases more than that in the
Case (l) mentioned above. This arrangement can be adopted, for
. example, when Gl is Ca and G2 is CO, and a reduced C0 content
in the Ca can be expected although the yield of Ca is slightly
sacrificed.
. ~
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8~776
t4) In Cases ~1) to (3) mentioned above, the gases
are superheated vapors, but if Gl is a condensable gas, the
gas can be partially condensed by a special nozzle design. In
this case the deflection angle ~l (measured value) will be
smaller than Ql obtainable when Gl is a superheated vapor,
as shown in FIGURE 6. Therefore, ~1 can be replaced by
which teaches that the separator screen 3 should be located in
the neighborhood of A~l depending upon the condensed condition
of the gas. Here the following formula is established: -
~ ~ Q~
Preferably the separator screen is located such that
the equation ~ = ~l + /2 is established. As the amount of
condensation is increased, ~1 will become smaller and smaller,
thereby increasing the separation efficiency. On the other
hand, the performance of the nozzle will become unstable. If
G2 is a condensable gas, the separation efficiency will be
lowered due to a reduction in deflection angle ~2 produced
by the partial condensation thereof.
(5) When more than three gases of different ratios
of specific heat are to be separated, e.g. Gl, G2 and G3, whose
deflection angles are respectively ~l' ~2~ and ~3. The
separation of these gases will be effected by employing a
plurality of separator screens in the same manner as mentioned
above.
(6) For a multistage separation the same procedure
can be repeated. In Case (1~, the gas Gl contains G2 inside
the separator screen. The gas Gl containing G2 is again
e;ected at supersonic speed through the nozzle in the same
manner as initially carried out. In this way the G2 content
in Gl can be gradually reduced, thereby enhancing the purity
of the gas Gl stage by stage.
.
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lQ8g776
The location and operation of the separator screen
is not limited to the embodiments mentioned above, and various
modifications are of course possible.
For industrial utilization of the present invention
some typical examples will be shown as follows:
(1) The reduction of calcium oxides by carbon is
expressed by:
more than about 2000C
CaO + C ~ ~ Ca + CO
<less than about 2000C
wherein the reaction chamber has a pressure of one atmosphere.
However, the Ca and CO thus produced are very reactive, and
accordingly it is necessary to cool them instantaneously to
a temperature at which they are not reactive with each other.
However, if they are cooled but still remain at more than
200C, the reaction tends to advance in the left-hand direction.
, In view of the fact that Ca is a monoatomic gas while CO is
a diatomic gas, the present invention can be utilized to effect
an instantaneous separation of Ca and CO by the instantaneous
cooling of the gaseous mixture. Thus calcium can be obtained
in a highly pure form.
(2) The reduction of magnesium oxides by carbon ~ ;-
takes place in the same manner as (l), with the only difference
being in the equilibrium temperature. In this case, pure Mg
can be obtained equally easily by the present invention. In
general, when a metal oxide is to be reduced by solid carbon
at a temperature of more than 1000C, the reaction is expressed
by:
MexOy ~ yC ~ ~ xMe + yCO
wherein CO is a diatomic molecule gas while Me is a monoatomic
gas, so that it is possible to utilize the present invention to
prevent the reverse reaction by separating the metal gas from
1 1
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1~89776
the C0 gas.
(3) When methane gas is heated to a high temperature
it dissociates and produces acetylene, that is:
2CH4 _ ~ C2H2 + 3H2
In view of the fact that C2H2 is a multi-atomic
molecule gas while H2 is a diatomic gas, whose ratios of
specific heat are different, the present invention can be
utilized to separate the gaseous mixture into C2H2 and H2.
If a multistage separation mentioned above is adopted, the
purity of the gas thus obtained will be increased.
(4) Air contains a small amount of Ar (about 0.93%
by volume), and when air having no Ar content is to be produced,
the common practice is to liquefy air and then to effect a
fractional distillation of it. It is costly and requires a
long time. However, this disadvantage can be easily overcome
by the present invention, which utiliæes the difference in
the ratios of specific heat between monatomic Ar and air (which
may be treated as a diatomic gas when its ratio of specific
heat is considered). Thus the time and cost are immensely
reduced. In this case it is preferred that the separator
screen is located slightly outside the deflection angle of Ar. -
This is helpful in ensuring that air having no Ar content
exists outside the separator screen.
An apparatus adapted for use in carrying out the
methods mentioned above will be now explained by way of example
with reference to FIGURE 7.
An anti-pressure and anti-vacuum body 10 is provided
i with a lid 11, and is surrounded by a cooling jacket 12. A
,
thermally insulating chamber 13 is provided inside the body
10, in which a furnace 14 of heat-proof material is installed.
An electric heater 15 is provided between the walls of the
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397~;
chamber 13 and the furnace 14. The furnace 14 has an inlet
pipe 16 inserted from its ceiling, through which a treating
material 17 can be supplied into the furnace. A gas ejecting
pipe 18 is supported with its opening situated in the gas-
phase section of the furnace, and a divergent nozzle 20 is
attached to the opposite end of the pipe so that the gaseous
mixture can be ejected therethrough in a potentially expansive
state. Preferably the nozzle can be easily replaced in
accordance with the purposes of separation. The body 10 is
10 provided with a thermocouple 21, which is inserted into the
chamber 13 in such a manner as to withstand pressure and
vacuum. The temperature inside the furance 14 is measured by
means of an optical pyrometer through an aperture 23 produced
in the wall of the chamber 13, and is read through a watching
window 22. The lid 11 is provided with a pressure gauge 24
to indicate the internal pressure of the furnace. The rate of
material supply is controlled by a suitable valve 25.
The body 10 is connected to a lower body structure 26,
which is also surrounded by a cooling jacket 12. Within the
20 lower body structure, a separator screen 27 is provided such
that its top portions are spaced from the nozzle 20, and so
that it is situated inside the maximum deflection angle with
respect to the constituent gases to be separated, whereby
the gaseous mixture may be separated into the constituent gases
28 and 30. The lower body structure 26 is also provided with
a thermocouple 31. Each constituent gas is sucked into
collecting pipes 32 and 33 by means of vacuum pumps 36 and 37,
and the pipes are provided with condensers 34 and 35. Each
pipe 32 and 33 is connected to a sample collector conduit 42,
30 from which the sample is taken by means of a vacuum pump 43.
The conduit is provided with a vacuum indicator 38, valves 40,
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977~;
and a sample collector 41.
A typical example of the operation of the apparatus
described above is explained as follows.
The material 17 is heated in the furnace 14 to produce
a gaseous mixture,which is introduced into the ejecting pipe 18.
In this way, the gaseous mixture is ejected at supersonic speed
through the divergent nozzle 20. The ejected gaseous mixture
is separated into constituent gases 28 and 30 by the screen 27,
and each constituent gas is collected for analysis at room
temperature. The amount of gas collected will be decided by
the pumping speed, performance and the applied pressure of the
pumps, which are generally known. When a condensable gas is
present, it is arranged that the gas is collected in the lower
body structure 26 and the condensers 34 and 35, thereby
preventing it from escaping to the vacuum pumps 36 and 37.
A non-condensable gas is collected in the manner mentioned
above. The suction ability of the vacuum pump depends upon
the type of gas to be treated, and in actual use some adjustment
will be required.
Preferably the separator screen can easily be exchanged
in accordance with the purpose of separation, and more than one
screen can be installed, depending upon the number of gases to
be separated.
The present invention will be better understood by
the following Examples.
EXAMPLE 1
Gaseous Ca and CO obtained by the reaction formula
CaO + C = Ca + CO were separated, and the results are shown
- in TABLE 1. The starting materials consisted of CaO and C
mixed in briquette. In TEST NO. 1 the Ca and CO were superheated
vapors at the nozzle outlet, while in TEST NO. 2 only the Ca was
partially condensed at the nozzle outlet.
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T ABI.E
TEST NO. 1 TEST NO. 2
Temperature at nozzle entry (ToC) 2027 1927
Total pressure at nozzle inlet 7.5 93.8
(PO Torr)
Expansion ratio of the nozzle 7.5 12.5
employed: X = PO
Temperature at nozzle outlet (TlC) 902 675
Total pressure at nozzle outlet 1 7.5
(Pl Torr)
Partial pressure for Ca (0.5 Torr) (3.75 Torr) -
External pressure at nozzle outlet 0.015 0.188
(P Torr)
p/pO 1/500 1/500
Deflection angle ~l at Ca side 40.9 ~l = 33.5
~1 = 23
Deflection angle ~2 at CO side 52.7 42.2
Angle ~ of the separator screen 48.9 31
L/D 1.5 1.75
20 Gas outside the separator screen CO: 54.6 CO: 65.3
(Wt.%) Ca: O Ca: O
Gas inside the separator screen CO: 45.4 CO: 34.7
~Wt.%) Ca: 100 Ca: 100
The Mach number of CO Ml: 1.97 Ml: 2.30
M2: 4.95 M2: 4.95
The Mach number of Ca Ml: 1.93 M : 2.29
M2: 5.75 Ml: 5.75
EXAMPLE 2
. _
Mg and CO gases obtained by the reaction formula
MgO + C = Mg + CO were separated. The results are shown
in TABLE 2. The starting materials consisted of Mgo and C
mixed in briquette. In TEST NO. 1 the Mg and CO were super-
heated vapors at the nozzle outlet, while ln TEST NO. 2 only
the Mg was partially condensed at the nozzle outlet.
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3977~
TABLE 2
TEST N0. 1 TEST N0. 2
Temperature at nozzle inlet 1927 1727
(T C)
Total pressure at nozzle inlet69.7 139
(poTorr2
Expansion ratio of the nozzle 7.5 12.5
employed: 1 = Po
Temperature at nozzle outlet 851 588
(Tl C~ . -
Total pressure at nozzle outlet9.3 11.1
(Pl Torr)
External pressure at nozzle 0.14 0.28
outlet (P Torr)
P/PO 1/500 1/500
Deflection angle Qal at Mg side40.~ ~91 = 33.5
= 19.5
Deflection angle ~e2 at C0 side52.7 42.2
Angle ~ of the separator screen48.9 27.5
- . .
L/D 1.5 2.1
I Gas outside the separatorC0: 53.5 CO: 73.6
', screen (Wt.%)Mg: 0 approx. Mg: 0 approx.
Gas inside the separator C0: 46.5 C0: 26.4
screen (Wt.%) Mg: 100 approx. Mg: 100 approx.
The Mach number of C0Ml: 1.97Ml: 2.30
E~2: 4.95 M2: 4 95
The Mach number of MgMl: 1.93Ml: 2.29
M2: 5.75 M2: 5.75
EXAMPLE_3
In TEST N0. 1, C2H2 (K=1.26~ and E12 produced in a
reaction expressed by: 2CH4 ~ C2H2 + 3H2 were separated
(resistance heating was adopted~, and in TEST N0. 2, C2H2, H2
and Ar produced in a reaction expressed by: 2CH4 + 0.2Ar ~
C2H2 + 3H2 + 0.2Ar were se-parated (plasma heating was adopted).
The results are shown in TABLE 3.
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` 1(~1~9776
TABLE 3
TEST N0. 1 TEST N0. 2
Temperature at nozzle inlet 1500 1500
(To C)
Total pressure at nozzle inlet 1000 1000
(PO Torr)
Expansion ratio of the nozzle 12.5 12.5
employed: 1 = P
Temperature at nozzle outlet 738 633
( Tl C)
Total pressure at nozzle exit 80 80
(PlTorr)
External pressure at nozzle 2 2
outlet (P Torr)
P/P 1/500 1/500
Deflection angle ~1 at Ar - 33.5
side
Deflection angle ~2 at H2 42.2 42.2
side
Deflection angle ~03 at C2H2 48.8 48.8
. side
Angle ~ of the inner separator 50.2 50.2
screen
Angle y of the outer separator - 3-.5
screen
L/D 1.5 1.5
The Mach number of C2H2Ml = 1.68Ml = 1.68
M2 = 4.48 M2 = 4.48
The Mach number of H2 . Ml = 2.30 Ml = 2.30
M2 = 4~95
The Mach number of Ar - Ml = 2.29
M = 5.75
Gas inside the inner separa- C2H : 67 C H : 42
tor screen (Wt.%) 2 2 2
H2: 100 approx. H2: 62
; Ar: 100 approx.
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Gas between tlle inner and outer - 2 2
separator screens (Wt. %)
H2: 38
Ar: 0 approx.
Gas outside the outer separator 2 2 2 2
screen (Wt. %)
H2: approx- H2:
Ar: 0 approx.
TABLE 4 shows the difference in the deflection angles
~l and ~2 at the Ca and C0 sides between the values obtained
by measurement and by calculation. The data was obtained in
carrying out EXAMPLE 1.
TABLE 4
(Actual Measurements) (Calculation)
(Times) 1st 2nd 3rd 4th 5th mean fig.
~l (Ca): 41.8 40.4 39.9 42.1 40.4 40.92 40.89D
~2 (C0): 52.2 53.6 52.0 52.5 53.4 52.74 52.70
As is evident from this table, no substantial differ-
ence exists between the figures obtained by measurement and
calculation, and from this it will be apparent that the
separator screen can be located at its optimum position by a
previous calculation of the deflection angle of a gas to be
separated.
The following advantages may thus be achieved by the
present invention.
(1) A gaseous mixture consisting of gases having
different ratios of specific heat can be separated into its
constitu~nt gases with good efficiency, and additionally, at
high speed on account of the utilization of supersonic speeds;
(2) The yield of each separation may be higher than
by any other known expedient, and it is easy to repeat the
separating process, thereby enhancing the degree of separation;
(3) When the constituent gases contain a condensable
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177S~
gas, the efficiency of separation can be remarkably increased
by allowing the same to condense partially according to the
particular design of the nozzle;
(4) The method of the invention need not be carried
out in complicated equipment. The apparatus can be quite
simple and, with the use of heat-insulating material, high
~ temperature gaseous mixtures can be treated;
(5) If the gaseous mixture consists of gases likely
to mix with each other at an elevated temperature, an instan-
taneous separation is possible by instantaneously cooling the
. gases to a temperature at which recombination is not possible,
thereby ensuring that the constituent gases can be collected
without tixing with each o~her.
.
. 20
