U.S. patent number 3,687,176 [Application Number 05/020,626] was granted by the patent office on 1972-08-29 for phase separator.
This patent grant is currently assigned to United Aircraft Products, Inc.. Invention is credited to Anson S. Coolidge, Joseph F. Fernandes.
United States Patent |
3,687,176 |
Fernandes , et al. |
August 29, 1972 |
PHASE SEPARATOR
Abstract
A body providing an interior helical flow path for separation of
fluid in the vapor phase from a flowing liquid stream. Separate
passages lead from the flow path and from one end of the body and
in one of these is venturi means exerting an eduction influence on
the other passage.
Inventors: |
Fernandes; Joseph F. (Dayton,
OH), Coolidge; Anson S. (Dayton, OH) |
Assignee: |
United Aircraft Products, Inc.
(Dayton, OH)
|
Family
ID: |
21799686 |
Appl.
No.: |
05/020,626 |
Filed: |
March 18, 1970 |
Current U.S.
Class: |
141/59; 141/286;
96/212; 55/311; 141/301 |
Current CPC
Class: |
F25B
31/002 (20130101); F17C 13/00 (20130101); F17C
2203/0629 (20130101); F17C 2205/0323 (20130101); F17C
2227/04 (20130101); F17C 2205/0329 (20130101) |
Current International
Class: |
F17C
13/00 (20060101); F25B 31/00 (20060101); B65b
031/04 (); B67c 003/02 () |
Field of
Search: |
;141/18,29,285,286,291,292,293,294,295,296,301,302,392,374,94,95,59,37-53,54-58
;138/37-46,111-117 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bell, Jr.; Houston S.
Claims
What is claimed is:
1. A device for separating vapor phase fluid from a flowing liquid,
including a body providing a flow path for the liquid in which
centrifugal forces are utilized for a release of vapor phase fluid
with a directed escape thereof through a vapor phase flow passage
to a vapor outlet, a separate vapor flow passage in said body
leading to said outlet, and means utilizing vapor flow through one
of said passages to induce flow in the other passage.
2. A device according to claim 1, wherein the first said flow
passage includes venturi means and wherein said separate flow
passage communicates with said first flow passage in position to be
evacuated by flow through said venturi means.
3. A device according to claim 1, wherein said body provides a
liquid inlet and an internal helical path terminating in a
discharge opening at one end thereof, the first said flow passage
forming venturi means centrally of said helical path through which
vapor phase fluid released from liquid in said helical path
escapes, said separate vapor flow passage opening through said one
end of said body and leading to the first said flow passage at a
location to have flow therethrough influenced by flow through said
venturi means.
4. A device according to claim 3, wherein said helical flow path is
formed in a first chamber in said body, a second chamber therein
being longitudinally spaced from the first chamber and connected
thereto by said venturi means, said vapor outlet communicating with
said second chamber, and an opening in said body communicating with
the first said chamber for admitting liquid to said helical
path.
5. A device according to claim 4, characterized in that said device
is useful on and in connection with a vessel, said discharge
opening and the said separate flow passage communicating through
said one end of said body with the vessel interior.
6. A device according to claim 5, characterized by a spring loaded
valve normally seated in to close said venturi means and opening
under released vapor pressure in said first chamber, said separate
vapor flow passage extending to said venturi means in position to
be closed by said valve when seated therein.
7. A device useful in the liquid filling of vessels to facilitate
separation and removal of fluid in the vapor phase, including a
body adapted to mount on to be a part of a vessel, said body
providing a flow path for in-coming fill liquid in which entrained
vapors are inherently released and having an outlet through which
such released vapor escapes prior to reaching said vessel, and
means utilizing escaping vapor released in said flow path to induce
vapor flow from the vessel interior.
8. A device according to claim 7, characterized by pressure
responsive valve means intermediate said flow path and said vapor
outlet restricting escape of released vapors.
9. A liquid container of rapid fill characteristics, including a
container having a mouth through which it is filled and through
which contained liquid is drawn off, a body installed in a closing
relation to said mouth and having a liquid flow passage for fill
and draw off, means in said passage way imparting a centrifugal
effect to in-coming liquid for a release of vapor phase fluids
therefrom, and means in said body providing for escape therefrom of
released vapor phase fluid prior to reaching said container.
10. A liquid container according to claim 9, characterized by a
valve biased to restrict escape of vapor phase fluids for a
pressurizing of the container interior.
11. A liquid container according to claim 9, characterized by a
separate flow passage way intercommunicating said last named means
and the vessel interior providing for the escape of vapor phase
fluids released in the container.
Description
BACKGROUND OF THE INVENTION
This invention relates to a device separating a two-phase fluid
into liquid and gas components. Although not so limited, it has
special reference to liquid containers and particularly to means
allowing the rapid filling of such containers with a saturated
liquid. In a specific embodiment, the invention deals with the
problem of filling containers with cryogenic fluids, that is, with
oxygen, liquid hydrogen or the like, rapidly and without excessive
loss by vaporization. In the pertaining fluid handling art,
cryogenic fluids are taken from bulk storage and transferred to
double walled vessels known as dewars, by which they may
expeditiously be transported to a place of use and selectively
drawn upon as needed. The cryogenic fluid reaches the dewar in an
essentially two-phase form, substantial amounts of vapor being
liberated from the liquid due to warming and pressure decrease. A
vapor outlet from the dewar provides for escape of gases after they
have reached the dewar and after they have risen to the upper part
thereof. This is a relatively slow process, however, so that
filling of the dewar with a saturated liquid has heretofore been
slow and has been accompanied by excessive vapor loss.
The instant invention has in view a combined inlet-outlet fitting
constructed to promote phase separation before the cryogenic fluid
reaches the dewar interior. The liquid entering the dewar
accordingly flows at a higher mass flow rate. The filling time is
reduced and the amount of vapor phase fluid lost to the vent outlet
is reduced. In an optional feature of the invention, the separated
vapor phase fluid escapes through means utilizing the flow thereof
to evacuate the upper part of the dewar interior. Vapors released
within the dewar are thereby with greater facility conducted to the
vent outlet.
An object of the invention is to provide means of general utility
removing gas from a flowing stream comprising liquid and gas.
Another object of the invention is to provide separator means
allowing rapid filling of closed containers with saturated
liquid.
A further object of the invention is to provide a device which can
be installed on new or existing dewars and like vessels for a rapid
filling thereof with minimum vapor loss.
Other objects and structural details of the invention will appear
from the following description, when read in connection with the
accompanying drawings, wherein:
FIG. 1 is a partly diagrammatic view of a device in accordance with
the instant invention shown applied to a dewar for the handling of
cryogenic fluids; and
FIG. 2 is a detail, fragmentary view showing a valve in the device
of FIG. 1 in an open position.
Referring to the drawings, the invention is disclosed in a system
handling cryogenic fluids. In such systems, a cryogenic fluid such
as liquid oxygen or liquid nitrogen is taken from a place of bulk
storage and transferred to a dewar 10 by which the cryogenic fluid
is transported to a place of use and drawn upon as required. The
dewar 10 is a double walled insulated container comprised of spaced
apart inner and outer walls 11 and 12. Inner wall 11 defines the
interior storage compartment of the container, a space herein
indicated at 13. A relatively small diameter mouth 14 at the upper
end of the dewar provides an entrance to and exit from interior
space 13.
The illustrative concept of the invention provides a body 15, an
end of which seats on the reduced diameter upper end of the dewar
10 in a closing relation thereto. Thus, outer wall 12 receives the
end of body 15 in an interfitting relation and is suitably secured
thereto, as by welding. The inner wall 11 is received in a recess
16 in the end of body 15 and similarly is secured, as by welding,
to the body. The space between the walls 11 and 12 accordingly is
effectively closed. The mouth 14 communicates with space 16.
The body 15 has a through longitudinal bore 17. At what may be
considered the upper end of the body, or that end remote from
recess 16, a counterbore 18 is formed. A threaded bushing 19 is
installed in to close the upper end of counterbore 18. An
interiorly threaded portion 21 of the bushing 19 provides a place
of mounting for a combination seal and bearing element 22. A rod 23
has a sliding bearing in element 22 and extends downwardly through
the bore 17 of body 15 into container space 13. The rod 23 is a
level indicator and is adapted selectively to be capable of
relative vertical movement in the assembly comprising dewar 10 and
body 15. A housing 24 is secured to the upper end of body 15 by
bolts 25 and extends upward in a closed, surrounding relation to
rod 23 in a manner which it is unnecessary here to consider. A tube
26 is mounted at its ends in the body 15 and in the bushing 19 and
provides an enclosure for the rod 23.
A portion of the body 15 between its ends is constructed as an
interior chamber 27. Integrally formed in the wall of the chamber
27 is a helical passageway 28. An upper end of passage 28
communicates with a lateral, through opening 29 in the side of the
body wall. A lower end thereof is turned longitudinally downward in
radially offset relation to the body axis and opens into recess 16.
A pipe 31 is installed in opening 29 and provides a combined fill
and draw off means. A valve 32 is interposed in pipe 31 and is
manually adjustable to an open and to a closed position with
respect to flow through the pipe. At the lower end of passage 28, a
tube 33 has one end extending through recess 16 to be received in
and communicate with passage 28. The tube 33 extends vertically
downward into container space 13 and may advantageously project to
a point near the bottom of such space.
The body chamber 27 is connected to counterbore 18 by a curving
interior body surface 34 which expands as it extends toward
counterbore 18 to define a conical surface 35. Curving surface 34
defines with the exterior of tube 26 a restricted flow passage 36.
The surface 35 provides a seat for a valve 37 which surrounds tube
26 and in seating on surface 35 effectively closes passage 36. A
compression spring 38 seats on the bushing 19 and urges valve 37
normally closed.
The body chamber 27 communicates at its lower end with the recess
16, and thereby with container space 13, through an opening 39. The
upper part of the chamber 27 communicates with one end of a curving
passage 41, the other end of which opens through conical surface
35. The described other end of passage 41 is closed in a seated
position of valve 37 and opened in a raised or open position of the
valve. Opening 39 and passage 41 are connected by a tube 42.
The body 15 has circumferentially spaced apart radial openings 43
and 44 communicating at their inner ends with counterbore 18.
Installed in to close opening 43 is a fitting 45 incorporating a
rupture disc (not shown). A pipe 40 is screwed into opening 44 and
extends to atmosphere or to a suitable place of vent. A manual
valve 46 is interposed in pipe 45 and is alternatively adjustable
to open and close such pipe to a flow of fluid therethrough. The
counterbore 18 is further connected to vent or to the atmosphere by
other, pressure responsive, means, and, for convenience of
illustration, this has been shown diagrammatically as a line 47
incorporating a pressure relief valve 48 and communicating with
pipe 40 in advance of valve 46.
The cryogenic fluid is in storage maintained under pressure and in
a substantially saturated condition. In the transfer operation,
from storage to a dewar, use is made of the inherently pressurized
condition of the fluid or pumps are utilized. In either event, the
fluid reaches the body 15 as a two-phase fluid comprising whole
liquid and entrained gases or vapors. Pressure reduction produces a
gas in the fluid. Also, warming of the fluid which is a necessary
result of directing it through pipe lines and passages to the
dewar, releases vapors.
The opening 29 has a non-radial disposition. It aligns tangentially
of chamber 27 or more particularly of helical passage 28 therein.
In entering passage 28, therefore, the two-phase fluid supplied
through pipe 31 goes into a swirling movement producing results
characteristic of a centrifugal separator. Heavy liquid particles
go to and remain in the outside of passage 28 while lighter vapors
and gases separate from the liquid and move toward the center of
chamber 27 where they rise along the exterior of tube 26 to and
through passage 36. A pressure difference across valve 37 is
established, causing this valve to raise to an open position,
substantially as shown in FIG. 2 of the drawings. An open flow
passage accordingly is defined from chamber 27 through passage 36
into counterbore 28 and out passage 44 to and through vent pipe 40.
The devaporized liquid continues in its path through passage 28 and
discharges therefrom into tube 33 to be conducted thereby to
container space 13, the tube 33 terminating as before indicated at
any selected level within the container space. The unseating of
valve 37 opens the passageway defined by opening 39, passage 41 and
tube 42, which passageway communicates through the open mouth 14 of
dewar wall 11 with the container space 13 in the upper part
thereof. Accordingly, vapors released within space 33 and rising to
the top thereof are free to join the centrifugally separated gases
and exit through vent pipe 45. The arrangement is such that the
cryogenic fluid enters tube 33 in a saturated condition and flows
at a higher mass flow rate than would be the case if it were in the
form of the two-phase mixture in which it reaches body 15. Further,
released gases within the container space 13 are expeditiously
removed by way of tube 42 and communicating passages so that there
is little resistance to a quick and easy filling of dewar interior
space 13. In this latter connection, the curving surface 34 of body
15 which defines passage 36, and the divergently inclining surface
35 leading upwardly therefrom form a passageway having the
characteristics of a venturi. The location of passage 41 is such
that it and communicating spaces are subjected to an education
influence as centrifugally separated vapors rise through the
passage 36 and expand into the continuation thereof defined by
conical surface 35. The education effect, exerted upon the upper
part of container space 13 assists in the exhausting of this space
of released vapors.
In a fluid transfer operation, manual vent valve 46 is opened and
the manual fill-drawoff control valve 32 is open. The two-phase
fluid, as represented by the stippled arrows 49 is free to flow
through pipe 31 into helical passage 28. Saturated liquid,
represented by solid arrows 51 reaches tube 33 and is directed
thereby toward the bottom of container space 13. Released vapors,
as represented by open arrows 52 flow to vent pipe 40 by way of
venturi passage 36 and by way of tube 42. When filling is complete,
both valve 32 and manual vent valve 46 are closed. Pressure in the
dewar, which is function of the continuing attempted expansion of
the cryogenic fluid, equalizes in chamber 27 and in counterbore 18
whereupon valve 37 closes. When it is desired to draw off liquid
from the dewar valve 32 is opened. Internal pressure forces liquid
from the space 13 upward through tube 33 and through chamber 27 to
opening 29 and pipe 31 which at this time assume the character of
outlets for the discharging liquid.
If, while the liquid is stored in dewar 10, internal pressures rise
to an undesirable height, valve 48 relieves to vent excess
pressure. The rupture disc in fitting 45 serves a similar function
in the event valve 48 is inoperative or unable to vent pressure at
a desired rate.
Used with unpressurized liquid containers, the device of the
invention would omit valve 37 and may omit vent valve 46. Released
gases would flow directly to the atmosphere or place of
venting.
It is evident, moreover, that the device provides a phase separator
of general utility, structural details of which may vary
substantially within the broad concept characterizing the
invention.
The invention allows rapid filling of closed containers with
saturated liquid. It is of maximum advantage when the source fluid
is composed of both liquid and gas phases. Its most apparent
application is in the filing of dewars with cryogenic fluids.
However it will function with other fluids, and can be used to
extract liquid samples from a two phase stream of fluid. A device
according to the invention will normally be used to fill vessels
with liquid from a source which is at a pressure above ambient.
In the illustrative embodiment of the invention, it has been
assumed that vapor rise through opening 36 is a primary flow while
that discharging from space 13 through tube 42 is a secondary flow.
Should conditions be such that the reverse is true, then the
structure of body 15 may appropriately be revised for a reverse
venturi effect. For example, level indicator 23 could be omitted or
relocated, the upper end of tube 26 flared outward in the manner of
surface 35, with radial openings at the base of such surface
communicating with counterbore 18, and a plug valve biased to close
flow through the tube past such radial openings. The vent
connection would be beyond the plug valve. The connection 39, 41,
42 would be omitted, with vapor flow out of the dewar being by way
of tube 26. Venting of vapor released from fluid in helical path 28
would be by way of the described radial openings in tube 26,
influenced by the primary flow thereby.
* * * * *