U.S. patent number RE30,632 [Application Number 05/923,625] was granted by the patent office on 1981-06-02 for separation apparatus.
This patent grant is currently assigned to Rhone Poulenc, S.A.. Invention is credited to Jacques Breysse, Jean Roget.
United States Patent |
RE30,632 |
Breysse , et al. |
June 2, 1981 |
Separation apparatus
Abstract
Separation apparatus useful particularly for ultrafiltration in
which a series of membranes are mounted in superposed relationship
with membrane supports, and, where appropriate, distribution plates
therebetween, the membranes being mounted in subassemblies so that
the flow of fluid through the individual chambers between the
membranes of a particular sub-assembly is substantially in
parallel. .Iadd.
Inventors: |
Breysse; Jacques (Villeurbanne,
FR), Roget; Jean (Lyons, FR) |
Assignee: |
Rhone Poulenc, S.A. (Paris,
FR)
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Family
ID: |
27249505 |
Appl.
No.: |
05/923,625 |
Filed: |
July 11, 1978 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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715659 |
Aug 19, 1976 |
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Reissue of: |
228887 |
Feb 24, 1972 |
03831763 |
Aug 27, 1974 |
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Foreign Application Priority Data
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Feb 25, 1971 [FR] |
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71.06493 |
Jun 1, 1971 [FR] |
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71.19774 |
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Current U.S.
Class: |
210/236;
210/321.84; 210/346 |
Current CPC
Class: |
B01D
61/18 (20130101); B01D 63/082 (20130101); B01D
2313/08 (20130101) |
Current International
Class: |
B01D
63/08 (20060101); B01D 031/00 () |
Field of
Search: |
;210/433M,321R,22,346,236 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Spear, Jr.; Frank A.
Attorney, Agent or Firm: Stevens, Davis, Miller &
Mosher
Parent Case Text
This is a continuation of Ser. No. 715,659, filed Aug. 19, 1976,
now abandoned. .Iaddend.
Claims
We claim:
1. Separation apparatus, useful especially for ultrafiltration,
said apparatus comprising, in combination:
a. two rectangular rigid end plates;
b. ends of said end plates;
c. means defining at least one inlet orifice in one end plate for
the introduction of the fluid to be treated and at least one outlet
orifice in the other end plate for the removal of the fluid to be
treated, said orifices being placed adjacent one end of the
associated end plate;
d. a plurality of membrane support plates of generally rectangular
shape, in overlying relationship with respect to one another, each
said support plate carrying a generally rectangular semi-permeable
membrane without apertures therein on each of its faces and having
duct means for the removal of the fluid which has crossed through
the said membranes;
e. first and second generally elongate apertures for the passage of
the fluid to be treated through the support plates, the first
apertures being adjacent one end of the support plates and aligned
with one another to form a first duct through the stack, in
communication with the inlet orifice of the said one end plate, the
second apertures being adjacent the other end of the support plates
and forming a second duct through the stack;
f. holding means extending between the two end plates effective to
hold the support plates in position;
g. jointing members separating said support plates in a leakproof
manner and enabling the fluid to be treated to pass in contact with
the membranes of two consecutive plates and flow substantially
parallel to the longitudinal axis of the said plates;
h. at least one intermediate plate in the stack dividing the said
stack into at least two sub-assemblies; and
i. one generally elongate opening through said intermediate plate
aligned with said second duct only.
2. Separation apparatus as claimed in claim 1, and further
comprising on each face of each support plate a recess in which a
membrane lies, said recess extending between the opposite elongate
apertures and being connected to at least one of said duct
means.
3. Separation apparatus as claimed in claim 2, in which each
support plate comprises at least one laterally extending duct
connecting the recess to an adjacent edge of the support plate.
4. Separation apparatus as claimed in claim 1, and further
comprising, on at least one face of each support plate, lateral and
transverse rims for the positioning and holding of a jointing
member.
5. Separation apparatus as claimed in claim 1, and further
comprising means defining a central opening in each jointing
member, the width of said opening being substantially equal to the
lateral extent of elongate aperture and the length of which is
substantially equal to the longest distance between the two
elongate apertures.
6. Separation apparatus as claimed in claim 2, in which the width
of each recess is at least equal to the lateral extent of the
elongate apertures.
7. Separation apparatus as claimed in claim 2, and further
comprising a permeable support in each recess on which support the
associated membrane rests.
8. Separation apparatus as claimed in claim 2, in which on each
face of the support plate a membrane is attached in a leakproof
manner to the transverse zone of the said plate between the recess
and the adjacent elongate aperture.
9. Separation apparatus as claimed in claim 1, in which the means
for holding the support plate comprises a member extending between
the two end plates and slots supported in the support plates in
which said member engages.
10. Separation apparatus as claimed in claim 1, and further
comprising a distribution plate situated between two consecutive
membrane support plates, said distribution plates being of
generally rectangular configuration and comprising first and second
generally elongate apertures in communication with the first and
second apertures of the support plate, means defining openings
inwardly of first and second apertures of said distribution plates,
a distribution bar having longitudinal channels formed therein
separating each opening from its associated first and second
aperture, bevelled edges to said distribution plates defining the
inner edges of said openings and jointing members separating said
support plates and said distributing plates, in a leakproof manner,
whereby the fluid to be treated passes between the support plate
and the distribution plate with the fluid flowing substantially
parallel to the longitudinal axis of said plates. .Iadd. 11.
Separation apparatus, useful essentially for ultrafiltration, said
apparatus comprising, in combination:
(a) two rigid end plates;
(b) ends of said end plates;
(c) means for defining at least one inlet orifice in one end plate
for the introduction of the fluid to be treated and at least one
outlet orifice in the other end plate for the removal of the fluid
to be treated, said orifices being placed adjacent to one end of
the associated end plate;
(d) a plurality of membrane support plates in overlying
relationship with respect to one another forming a stack, edges of
said support plates being open to the exterior of the apparatus,
means defining a recess in each face of each support plate, each
said support plate carrying a semi-permeable membrane on each of
its faces, each membrane covering a recess, each recess having
means for supporting the said membrane for enabling the removal of
the fluid which has crossed through the said membrane, and at least
one duct means, the said duct means opening onto an edge of the
said support plate which is open to the exterior of the
apparatus;
(e) first and second apertures for the passage of the fluid to be
treated through the support plates, the first apertures being
adjacent one end of the support plates and aligned with one another
to form a first duct through the stack, in communication with the
inlet orifice of said one end plate, the second aperture being
adjacent the other end of the support plates and forming a second
duct through the stack;
(f) holding means extending between the two end plates effective to
hold the support plates in position;
(g) jointing means provided near the periphery of each support
plate and beyond the first and second apertures thereof, the said
means sealing the support plate in a leak-proof manner to the
adjacent support plate and determining the thickness of the layer
of fluid to be treated flowing from one duct of the stack to the
other, between and in contact with the membranes of two consecutive
support plates;
(h) at least one intermediate plate in the stack dividing the said
stack into at least two sub-assemblies; and
(i) one opening through each said intermediate plate aligned with
only one of the two ducts to the stack, said intermediate plate
enabling the fluid to be treated to flow in parallel in a
sub-assembly and in series from one sub-assembly to the other.
.Iaddend.
Description
The present invention relates to a separation apparatus employing
semi-permeable membranes, which can be used for filtration,
hyperfiltration, inverse osmosis, gas permeation and especially
ultrafiltration operations, for the purpose of carrying out
different types of operations such as concentration or
purification.
Ultrafiltration apparatuses employing plane membranes are known,
for example from U.S. Pat. No. 3,398,091, in which the liquid
follows a tortuous path as it passes from chamber to chamber. A
high degree of filtration can be achieved, but if it is necessary
to have a high flow rate there is always a consequent high pressure
drop.
According to the present invention there is provided separation
apparatus, useful especially for ultrafiltration, such apparatus
comprising two rigid end plates, at least one inlet orifice in one
end plate with at least one outlet orifice in the other end plate,
such orifices being placed adjacent an end of the associated end
plate, a plurality of plane membrane support elements stacked
between the end plates in overlying relationship, semipermeable
membranes carried by the membrane support elements and defining,
with said support elements, chambers, first and second apertures in
the membrane support elements, the first aperture being adjacent
one end of the support elements and aligned with one another to
form a first duct through the stack, in communication with the
inlet orifice of said one end, the second aperture being adjacent
the other end of the support elements and forming a second duct
through the stack, means connecting said ducts to each chamber, at
least one intermediate plate in the stack dividing the stack into
at least two sub-assemblies, the intermediate plate being provided
with an opening aligned with the second duct only.
In effect with such an apparatus the flow in the various chambers
of a sub-assembly is in parallel, so that without any reduction in
the area available for filtration, it is possible to carry out the
filtration at high flow rates with only low pressure drops.
With the apparatus of the present invention it is possible to
detect the rupture of a membrane easily and the element supporting
the membrane can be readily removed and replaced.
The apparatus according to the invention has also the advantage of
being able to be easily cleaned and can be constructed from any
material, especially from plastic materials of medical or foodstuff
quality, and of being of a relatively low cost price.
The present invention will be better understood from the following
description, which is given only by way of example, reference being
made to the accompanying drawings, in which:
FIG. 1 is a partial exploded perspective view of one embodiment of
apparatus according to the invention;
FIG. 2 is a front elevation of a distribution plate of the
apparatus;
FIG. 3 is a cross-section along the line AA of FIG. 2;
FIG. 4 is a front elevation of a membrane support plate of the
apparatus;
FIG. 5 is a cross-section along the line CC of FIG. 4;
FIG. 6 is a front elevation of the assembly of the plates of FIGS.
2 to 5;
FIG. 7 is a view similar to FIG. 6 also showing a jointing member
assembled on the support plate;
FIG. 8 shows the same jointing member positioned relative to the
distribution plate;
FIG. 9 is a cross-section of the jointing member along HH of FIG.
8;
FIG. 10 is a partial view in cross-section of the sub-assembly of
the apparatus of the invention;
FIG. 11 is a flow diagram of the fluids in one form of apparatus
according to the invention;
FIG. 12 is a modified flow diagram;
FIG. 13 shows a detail of the packing arranged on a membrane
support plate;
FIG. 14 is a cross-sectional view taken along the line KK of FIG.
2;
FIG. 15 is a view similar to FIG. 7 of a modified construction;
FIG. 16 is a cross-section taken along the line LL of FIG. 15;
FIG. 17 is a view similar to FIG. 10 of this modified
construction;
FIG. 18 is a front elevation of a further embodiment of a membrane
support plate;
FIG. 19 is a cross-section taken along the line MM of the plate
shown in FIG. 18; and
FIG. 20 is a partial cross-sectional view of a sub-assembly using
the membrane support plates shown in FIG. 18.
The principal elements constituting the apparatus according to the
present invention are shown in FIG. 1. The apparatus consists of a
supporting frame P equipped with guiding rods 1, two end plates E,
the desired number of membrane support plates B, one or more
intermediate plates F and, optionally as shown, a distribution
plate D between each membrane support plate B.
In use, the plates are held tightly together by means of tie rods
2. A certain number of membrane support plates alternating
optionally with distribution plates can be joined together in
sub-assemblies, these sub-assemblies being bounded by an end plate
E and by an intermediate plate F, or by two intermediate
plates.
Thus the apparatus according to the present invention contains at
least one sub-assembly formed, either by alternately stacking
support plates B and distribution plates D, or by stacking only
membrane support plates B. Joints J or J1, according to the type of
stack chosen and will be referred to later, separate the
plates.
FIG. 1 shows in perspective a part of an apparatus containing more
especially a distribution plate D and a membrane support plate B of
a sub-assembly S which in fact contains several of these plates
juxtaposed in a leakproof manner and arranged vertically. These
plates D and B are positioned between an end plate E and an
intermediate plate F, provided with an elongate opening 7 arranged
as indicated later. Preferably, all these plates are rectangular.
The end plate E is attached to a guide device consisting of rods 1
which engage in slots in plates B and D, to hold these plates.
Plate E is formed with at least one orifice 6, either for the
introduction, or for the removal of the fluid to be treated. Tie
rods 2 pass through holes 3 in the end plates E and through holes 4
in the intermediate plates F. These tie rods 2 serve to clamp the
stack of plates, the clamping force being distributed over the end
plates E by means of channel section members 5.
A complete apparatus consists of two similar end plates E, one or
more intermediate plates F and two or more sub-assemblies, the
latter being linked among themselves in series, without an external
pipeline.
FIG. 2 and FIG. 3 show the details of construction of a
distribution plate D. Near its opposite extremities, this plate has
upper 8 and lower 9 guide and positioning slots, and two apertures
10 arranged in an essentially symmetrical manner relative to the
transverse axis of the plate. Each of these apertures 10 includes a
distribution bar 11 such as that shown in the FIGS. Each bar
contains a large number of equidistant, longitudinal ducts 12 shown
in cross-section in FIG. 14.
FIG. 4 and FIG. 5 show the details of construction of a membrane
support plate B. This plate has upper 13 and lower 14 slots, the
shape and positioning of which are similar to those of the
distribution plate D. These two plates B and D are essentially of
the same length, it being advantageous to have the membrane support
plate wider, as can be seen from FIG. 6, which shows the relative
positioning of the two plates, the distribution plate D being
represented by broken lines.
The membrane support plate B is formed with two elongate apertures
15 and 16 corresponding to and aligned with the apertures 10 in the
plates D for the introduction of the liquid to be treated and the
removal of this liquid. It is provided, on each face, with lateral
rims 17 and 18 and transverse rims 19 and 20 defining a frame, for
the positioning and the holding of the jointing member (described
later) during the tightening of the apparatus and while it is
subjected to pressure. Support plate B is formed with a recess 21
and 22 on each of its opposite faces divided by a partition. Each
of these receives a packing which will be described later and on
which a membrane rests. Ducts, 23 and 24 on the one face, and 25
and 26 on the opposite face (duct 26 is not shown in the Figure),
for the removal of the fluid which has crossed the membrane,
correspond to each of these recesses 21 and 22, and these ducts
discharge out of the chambers formed between the partitions of
plate B and the adjacent plates D.
Between each distribution plate D and membrane support plate B
there is a jointing member J, shown in FIG. 8 in heavy lines,
positioned relative to a distribution plate D, shown in fine lines.
The jointing member J has two elongated apertures 28 and 29
corresponding to the openings 10, 15 and 16 of the plates D and B
for the passage of the fluid, and a central opening 30
corresponding to the recesses 21 and 22.
FIG. 7 shows the jointing member J placed on a membrane support
plate B shown in fine lines. It can be seen that the jointing
member is supported externally by reinforcing lateral and
transverse rims 17, 18, 19 and 20.
Each membrane support plate B shown in FIG. 4 contains, inside the
recesses 21 and 22, a packing, the details of which are shown in
FIG. 13 in partial cross-section, corresponding to the end of FIG.
5. Inside the recess 22 going from the partition outwards, there
is:
a lattice 31,
a porous plate 32,
a filter paper 33 and
a membrane 34.
The thickness of this packing correspond substantially to the depth
of the recess. The jointing member J rests on the membrane and is
positioned as shown in FIG. 13.
The lattice can be made, for example, of a grid obtained from two
layers of crossed and heat-sealed polyethylene fibres. The porous
plate can, for example, be of sintered polyethylene or polyethylene
perforated with many channels.
In order to be able easily to replace a support plate B of which a
membrane has failed, it is of advantage to mount and arrange the
different elements of the packing in the following manner, the
plate at this time being horizontal.
The grid 31 and then the porous support 32, the dimensions of which
correspond to those of the recess, are placed at the bottom of the
recess 22, and the thickness of these two elements is essentially
equal to the depth of the recess 22. These two elements are then
held in position by means of an adhesive tape H (shown in FIG. 13)
the action of which is exerted partially on the porous support and
partially on the plate itself, this tape going right round the
recess under consideration. The action of the adhesive tape H is
exerted on the plate over a width which corresponds essentially to
the width marked at 35, between the apertures 15 or 16 and the edge
of the recess 22. By means of this tape the grid 31 and the porous
support 32 are firmly connected to the plate B.
A thin filter paper 33, the dimensions of which correspond to those
of the recess, is then arranged on the porous support, and then it
is covered with a membrane 34, the dimensions of which are slightly
greater than those of the recess.
The jointing member J, the position of which relative to the
support plate B is shown in FIG. 7, is then laid on the membrane
and on the support plate, between reinforcing lateral and
transverse edges 17, 18, 19 and 20, the jointing member J having
previously been coated with glue, preferably a glue which does not
harden, on its face which will be in contact with the membrane.
Thus on a membrane support plate, the packing, the membrane and the
jointing member are firmly connected and can easily be manipulated
together.
Thanks to this assembly, in a case of membrane rupture, the
jointing member J, the membrane 34 and the filter paper 35 can be
removed, without removing either the grid 31 or the porous support
32.
FIG. 10 is a cross-section of a sub-assembly S, in which the arrows
show the direction of circulation of the liquid to be treated
inside the apparatus. As will be seen, the flow of fluid in the
various chambers of a sub-assembly is in parallel, a chamber being
defined, in this case by a jointing member J, a membrane 34 and a
face of the distribution plate D adjacent the support plate B
carrying the membrane in question.
The membrane support plate B and the distribution plate D are
arranged between an end plate E and an intermediate plate F. The
jointing members J are arranged on the plates B. The fluid to be
treated crosses the elongated apertures 16 of the plates B, and
then the distribution bars 11, and thus is distributed on both
sides of the bevelled edge of the distribution plate D, and comes
in contact with the membranes 34. For simplification, the plates B
adjacent to the end plate E and to the intermediate plate F are
similar to those between the distribution plates D. The jointing
members 36 adjacent to the end plates E or to the intermediate
plates F have the same external dimensions as the jointing members
J, but have only one elongated aperture and do not have any central
opening 30.
In order to simplify the drawing, the distribution plate D has been
omitted between the two support plates B shown on the left of FIG.
10. Needless to say, the number of plates shown in FIG. 10 is not
imperative.
FIG. 11 is the schematic view of an apparatus containing three
sub-assemblies, S.sub.1, S.sub.2, and S.sub.3, internally linked in
series, and which thus consist of 2 end plates E and 2 intermediate
plates F. The intermediate plates F are identical to that shown in
FIG. 1, the opening 7 of these plates being in the axis of the
apertures 15 or 16 of the membrane support plates B. The broken
line carrying an arrow shows the direction and the general flow
path of the liquid to be treated from one sub-assembly to another,
whilst the arrows at the foot of each sub-assembly show the removal
of the fluid which has crossed the membrane.
FIG. 12 is the schematic view of a similar apparatus also
containing 3 sub-assemblies internally linked in series, but in
which the intermediate plates G are modified and contain an
internal channel which allows the fluid to be treated to have an
ascending path within each sub-assembly.
The thickness of the layer of fluid in contact with the membrane is
advantageously controlled by choosing a joint J of definite
thickness, and this determines the desired separation between the
distribution plate D and the membrane.
As has already been said at the beginning of the description, an
apparatus according to the present invention can contain only
membrane support plates B separated from one another by jointing
members J1, these support plates, placed side by side, being able
to form sub-assemblies separated from one another by intermediate
plates F. In this embodiment of the apparatus (see FIG. 17), the
jointing members J1 used are different from the jointing members J
used previously with distribution plates D because these members J1
do not have separate elongate apertures at their extremities but
rather have a large aperture extending along their length; this can
be better understood by referring to FIG. 15 which shows the
positioning of such a joint (in heavy lines) on a support plate (in
fine lines) and by referring to FIG. 16. The thickness of this
member J1 determines the thickness of the liquid layer between the
membranes of two consecutive support plates B. Needless to say the
number of plates shown is given purely by way of illustration, and
must be adapted to each appplication. In this apparatus the chamber
is defined by a jointing member J.sub.1 and the membranes of two
consecutive support plates B.
The packing of each recess of the support plates B, as well as the
assembling of the membranes, is carried out in a manner similar to
that described above. However, the membrane is attached, for
example, by sticking it on the adhesive tape in the transverse
zones 35 of the plate (see FIG. 15). In fact, these zones are no
longer pressed against the support plates by the jointing members
J1.
By way of a different embodiment, the membrane support plates can
be of the type shown in FIGS. 18 and 19. In such plates, the
longitudinal 17 and 18 and transverse 19 and 20 edges, marked in
FIG. 15, are now only on one single face of each plate. The
mounting of a sub-assembly with such plates is shown, by way of
example, in FIG. 20.
An apparatus containing only membrane support plates is of a
reduced overall size and of simple construction, and has proved
useful for the treatment of viscous or loaded materials.
Numerous other embodiments will be apparent to the man skilled in
the art, especially insofar as the elements of the packing are
concerned. The porous plate 32 can be replaced by paper or by felt,
and preferably by a non-woven filtering element, made of, for
example, polyethylene glycol terephthalate. It is also possible to
have, at the base of the cells, a section which allows the grid to
be dispensed with.
The filter paper 33 can also be removed in certain cases if the
surface of the support 32 is sufficiently smooth, and there is no
risk of tearing the membrane 34. The design of the plates of type B
in contact with the plates E or F can be simplified, since they
present only one active face.
An advantage of the apparatus according to the invention is that it
is rapidly adaptable for every application for which it is desired
to be used, and especially that it allows a high speed of the
treated fluid over the entire surface of the membranes with a very
low pressure drop, owing to the possibility of mounting the
sub-assemblies linked in series, each sub-assembly being able to
contain as many plates as desired, and owing to the choice of the
thickness of the layer of fluid treated.
Another advantage of this apparatus is the possibility of easily
detecting the rupture of a membrane because of the fact that there
are individual exits for the filtrate. It is thus easy to change
the corresponding membrane support plate, by simply sliding the
other elements along the guide bars.
Another advantage of this apparatus is that it allows the circuit
of the liquid to be treated to be cleaned easily, for example after
a long period of use, all the plates being easily accessible by
simply unclamping the apparatus.
The apparatus according to the invention can be constructed from a
number of different materials, depending on the particular use to
which it will be put, and the pressures which must be attained. It
lends itself well to construction from plastics, for example,
polyvinyl chloride. It can be constructed from plastics of medical
or foodstuff quality and this makes its use particularly valuable,
especially for the treatment of biological or foodstuff liquids. It
can also be used in ultrafiltration and hyperfiltration, and in the
chemical industry, the dyestuff industry, the paper industry and
the like. It can also be used in inverse osmosis and in gas
permeation.
* * * * *