U.S. patent application number 12/304372 was filed with the patent office on 2010-01-21 for split-chamber pressure exchangers.
Invention is credited to Fernando Ruiz del Olmo.
Application Number | 20100014997 12/304372 |
Document ID | / |
Family ID | 40739870 |
Filed Date | 2010-01-21 |
United States Patent
Application |
20100014997 |
Kind Code |
A1 |
Ruiz del Olmo; Fernando |
January 21, 2010 |
SPLIT-CHAMBER PRESSURE EXCHANGERS
Abstract
The invention relates to split-chamber pressure exchangers.
Split-chamber pressure exchangers are characterized in that the
pressure exchange chambers and the pistons thereof are split in
two. Each fluid passes through the corresponding chamber thereof,
such that said fluids cannot be mixed. The cross sections of the
chambers can be varied in order to vary the transmitted pressure.
The reverse line operation can be established and synchronized
using a U-shaped tube with telescopic sides and a fixed base filled
with fluid or diametrically opposed curved lines, and multiple
arrangements can be used. Split-chamber pressure exchangers can be
used as surface or well pumping systems and the pumping fluid used
can differ from the fluid to be pumped. Different levels of any
material can be exploited at any storage site using a chamber with
elastic walls filled with fluid and attached to the bottom.
Electric power can be generated by centrifuging the pre-pumped
fluid.
Inventors: |
Ruiz del Olmo; Fernando;
(Montequinto, ES) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
2040 MAIN STREET, FOURTEENTH FLOOR
IRVINE
CA
92614
US
|
Family ID: |
40739870 |
Appl. No.: |
12/304372 |
Filed: |
June 11, 2007 |
PCT Filed: |
June 11, 2007 |
PCT NO: |
PCT/ES07/00346 |
371 Date: |
June 17, 2009 |
Current U.S.
Class: |
417/399 |
Current CPC
Class: |
F04F 13/00 20130101 |
Class at
Publication: |
417/399 |
International
Class: |
F04B 9/10 20060101
F04B009/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 13, 2006 |
ES |
P200601694 |
Aug 17, 2006 |
ES |
P200602232 |
Claims
1-21. (canceled)
22. A split-chamber pressure exchanger (SCPE) in which the
available energy in a continuous flow of a pressurized fluid is
transmitted to a fluid to be pressurized, comprising a plurality of
chambers in which pressure exchange occurs, said chambers in fluid
communication with each other through a plurality of rigidly
attached discs or pistons, such that any contact between the
pressurized fluid and the fluid to be pressurized is eliminated,
said discs or pistons adapted to allow the cross sections of the
chambers corresponding to both fluids to change.
23. An SCPE according to claim 22, further comprising an auxiliary
U-shaped tube which interconnects both discs or pistons, and which
is telescopic at both sides of the "U", said tube being rigidly
supported by the base of the "U", wherein the "U" is filled with an
incompressible fluid, such that when the pressurized fluid enters
its chamber, it not only presses its disc or piston to displace the
fluid to be pressurized, but also transmits part of its energy to
the disc or piston of the other line to aid the fluid to be
pressurized of the other line to displace the other already
depressurized fluid in said line and to overcome friction of the
discs or pistons and their weight and the weight of the already
depressurized fluid if the assembly is vertical or angled.
24. An SCPE according to claim 22, wherein the chambers are curved
or circular with the chambers arranged in a diametrically opposed
manner, the chambers of each comprising different curvature radii,
and attachment parts between the discs or pistons is curved with
radius and attached to a center of the SCPE by means of a ball-type
joint, so as to allow increasing the pressure transmitted depending
on distance of the chambers of both fluids to the center without
needing to change the cross section thereof, wherein the attachment
parts between the discs or pistons are rigidly attached to one
another to assure reverse line operation so as to simplify system
control electronics, and to be able to displace the fluid which has
transmitted its pressure in the SCPE, once depressurized, from the
corresponding chambers thereof without a need for auxiliary pumping
for when the fluid to be pressurized enters under substantially low
pressure.
25. An SCPE according to claim 22, wherein the available energy in
a continuous flow of the pressurized fluid is exploited to transmit
to the fluid to be pressurized such that the chamber of the
pressurized fluid are split into several chambers, which can be
used depending on available pressure of the fluid, by means of an
electronically controlled valve system, thus achieving transmitting
substantially homogeneous pressure to the fluid to be pressurized
to form a multistage SCPE.
26. An SCPE according to claim 25, wherein by being provided with
circular chambers and a reverse operation system being aided by
means of the U-shaped tube for when the pressure at which the
pressurized fluid must be returned after depressurizing is
variable, and/or starting pressure of the fluid to be pressurized
is variable, wherein programming a control system so that stages
which must start operating depending on the pressures are
adjusted.
27. An SCPE according to claim 22, further comprising a variable
section in at least one of the chambers and pistons.
28. An SCPE according to claim 27, wherein by providing one of the
chambers with an initial variable section span, during which the
piston accelerates until reaching a certain speed when a straight
span of the chamber is reached, and the speed is kept constant
since at that time the force exerted on the piston by the
pressurized fluid is equal to the force exerted by the fluid to be
pressurized on the piston plus the losses due to friction
corresponding to the speed.
29. An SCPE according to claim 27, wherein by providing one of the
chambers with an initial span with a different section, during
which the piston accelerates until reaching a certain speed when a
straight span of the chamber is reached, and the speed is kept
constant since at that time the force exerted on the piston by the
pressurized fluid is equal to the force exerted by the fluid to be
pressurized on the piston plus losses due to friction corresponding
to the speed.
30. A recovery system comprising the SCPE according to claim 22 for
recovering energy from brine in desalination plants by reverse
osmosis, wherein contact between brine and pre-treated seawater is
prevented and section ratio between the chambers is such that the
pre-treated seawater is pressurized until a pressure necessary to
directly feed reverse osmosis filters without needing a booster
pump.
Description
FIELD OF THE ART
[0001] The invention is comprised within the field of pressure
exchangers, which are for transmitting dynamic pressure from one
fluid to another different fluid.
[0002] Due to the innovations provided, the invention is
transformed into a new pumping system for any type of fluids, and
even into a new electric power generation system.
STATE OF THE ART
Pressure Exchangers
[0003] Pressure exchangers were invented over more than twenty-five
years ago and they basically consist of pressurizing one fluid
(fluid 1 in FIG. 1) from the pressure of another fluid, which is
depressurized after the process (fluid 2). There are several
models, but they all basically work according to the diagram of
FIG. 1. The fluid 1 is introduced in the interconnecting chambers
by means of a system of shut-off and check valves, represented by
the gray boxes. Once filled, the fluid 2 is allowed to pass through
the other end, displacing said fluid by pushing an transmitting
intermediate member which transmits the residual pressure between
them, separating them (usually a disc or piston, though
occasionally an intermediate fluid or any other system is used).
The fluid 1 is thus pressurized. Then the inlet of the fluid 2 is
shut off and a discharge valve opens. The fluid 1 is again allowed
to pass through by means of the valve system, displacing fluid 2
(which now does not have pressure), discharging it through the
drain.
[0004] The system is assembled with two parallel interconnecting
lines and is electronically controlled such that at all times the
disc or piston of each tube is located in the opposite position
with regard to the center (reverse line operation) to thus achieve
the most constant pressure possible at the outlet of the fluid 1,
and to likewise achieve the greatest possible exploitation of the
pressure of the fluid 2.
[0005] FIG. 1 shows the fluids 1 and 2 using lighter shades when
they do not have pressure and darker shades when they are
pressurized. These different shades will be maintained throughout
all the figures attached to this description.
[0006] A thorough worldwide search has been conducted in the
espacenet database for patent documents relating to pressure
exchangers, and it has been found that although there has been
considerable development thereof, none of them provide the
innovations described herein.
Current Applications of Pressure Exchangers
[0007] Pressure exchangers have traditionally been used in mining
to displace residual processing water with clean water and the
system is used without discs or pistons since it does not matter if
both fluids mix.
[0008] They are starting to be used today in reverse osmosis water
desalination plants according to a scheme such as that depicted in
FIG. 2. The process is very simple: it pre-treats the water and
then raises the pressure of the water until it exceeds its osmotic
pressure. The water is then passed through reverse osmosis filters
which have a semi-permeable membrane and produce two outputs:
desalinated and depressurized water on one side and brine at a
fairly high pressure on the other side. This pressure is used to
pressurize part of the water coming from the pre-treatment, thus
reducing the output of high pressure pumps with the subsequent
electric power savings.
Pumping Systems
[0009] Many types of horizontal, vertical and submerged electric
pump units for clean water have been extensively developed to date,
as have many pumping systems for all types of fluids (waste water,
viscous fluids, toxic fluids, hazardous fluids, seawater,
chemicals, concrete, turbid water, or any type of fluid imaginable,
including fluids with solids in suspension).
EXPLANATION OF THE INVENTION
[0010] Technical Problems Involved with Traditional Pressure
Exchangers
[0011] Although the system proposed in the previous section
relating to desalination is fairly energetically efficient, it
presents two problems: [0012] the outlet pressure of the reverse
osmosis filters of the brine is always lower than that of the feed
water, which means that it is necessary to install a booster pump
increasing the pressure of the water [0013] since the pre-treatment
water and the brine are separated in the pressure-transmitting
intermediate members, there is always a small though significant
mixture of both fluids, therefore the pre-treatment water leaves
the pressure exchangers with a higher salt concentration, which
obviously jeopardizes the process
[0014] Furthermore, traditional pressure exchangers generally
present another drawback, which is that the fluid to be pressurized
(fluid 1) is forced to displace the fluid 2 once it has been
depressurized. This is not so much of a problem in the case of
desalinators because the water to be pressurized comes from the
pre-treatment process, from which it leaves with some pressure, but
in other applications it may be a serious drawback, especially
taking into account the fact that the reverse line operation is
necessary, and the natural speeds of the discs or pistons in either
direction are very different. This reduces the performance of the
exchangers and complicates the system control electronics.
[0015] All these drawbacks are probably what have not allowed
further development of pressure exchangers in all types of
applications.
Technical Problems Involved with Traditional Electric Pump
Units
[0016] Even though the designs of all types of electric pump units
are well optimized today, they have some shortcomings which until
now have been impossible to solve, such as: [0017] regarding
electric pump units for removing water from wells or collection
boxes, the motor of vertical units is on the surface, but they
cause many mechanical problems with the long shaft they require,
and submerged units have the problem that since the pump body and
the motor are submerged in the well or collection box, any
operating failure causes the unit to be out of service for a
considerable time period since the unit must be disassembled and
then assembled [0018] regarding the pumping systems for other
fluids, they have a lower performance in many cases and usually
offer many maintenance problems due to the inlet of solids, such as
the case of waste water pumping, or due to corrosion of the
delicate and expensive pump body, or due to both effects
GENERAL DESCRIPTION OF THE INVENTION AND SOLUTIONS PROVIDED
Split-Chamber Pressure Exchangers (SCPEs)
[0019] These are pressure exchangers characterized in that the
pressure exchange chambers are split in two, one for each of the
fluids, as shown in FIG. 3. Each of the fluids therefore only
passes through the corresponding chamber thereof, such that said
fluids cannot be mixed (and the second problem described in the
preceding section is therefore solved).
[0020] The exchange of pressures takes place by replacing the
pressure-transmitting intermediate members in traditional with two
rigidly attached discs or pistons, as shown in FIG. 3. The
pressurized fluid will thus push and also displace the other fluid
through the corresponding chamber thereof. The chambers obviously
need to have an opening to the outside to allow the inlet and
outlet of air during the movements of the discs or pistons and to
prevent vacuums, as can also be seen in FIG. 3.
[0021] Drains can be arranged at the opposite ends of the chambers
in case it is necessary to drain a small amount of the fluids which
may be lost through the disc or piston seals.
Arrangements
[0022] SCPEs with Piston-Type Chambers
[0023] A first possible arrangement would be the one shown in FIG.
3, in which the cross sections of each chamber are identical. The
same pressure would thus be transmitted from the pressurized fluid
to the fluid to be pressurized, except obviously mechanical
losses.
[0024] The inventive system allows another arrangement, in which
the cross sections of the chambers are different (FIG. 4), and
therefore the transmitted pressure is also different (the pressure
ratio will be equal to the area ratio, except obviously for
mechanical losses, since the net force is the same). The problem of
the need for the booster pump mentioned above in the description of
the technical problem involved can thus obviously be solved.
[0025] Obviously, the vertical or angled arrangement of the lines
is possible (FIG. 5), but this will worsen the problem that the
fluid to be pressurized (fluid 1) must displace the fluid 2 once it
has been depressurized, since in this case it must also overcome
the weight of the fluid, plus that of the discs or pistons and the
attachment between them. To that end an additional lifting system
thereof could also be arranged, the control of which would be
integrated in the electronic control system of the system, or the
drain system shown in FIG. 6 can be used, which consists of
exploiting the energy from the pressurized fluid (fluid 2) not only
to transmit it to the fluid to be pressurized (fluid 1), but also
to aid the actual fluid 1 in displacing fluid 2 in the other line
once it has been depressurized. This is achieved by means of an
auxiliary U-shaped tube which interconnects both lines as shown in
FIG. 6, and it is a telescopic tube on both sides of the "U", being
rigidly supported by the base of the "U". The ends of the "U" are
attached to the discs or pistons of their respective lines, and the
"U" is filled with an incompressible fluid. Therefore, when the
fluid 2 under pressure enters its chamber, not only does it apply
pressure to its disc or piston to displace fluid 1, but it also
transmits part of its energy to the disc or piston of the other
line to aid fluid 1 of the other line in displacing the
depressurized fluid 2 in said line and in overcoming the friction
of the discs or pistons and their weight and that of the
depressurized fluid 2 if necessary. Logically, the cross section of
the tube must be such that the energy transferred to the disc or
piston of the other line is the necessary minimum. The reverse line
operation is furthermore assured by means of this system, thus
simplifying the system control electronics. It can be assembled in
any type of pressure exchangers, whether they are split chambers or
not. Obviously, instead of being a telescopic tube they could be
several telescopic tubes equidistant from one another and from the
center, or a ring made up of several sections of the same length
and equidistant for the purpose of better distributing the stress
on the discs or pistons.
[0026] Finally, curved or circular chamber lines can also be
arranged, in which case the attachment between the discs or pistons
will be curved and have the same radius, and will be attached to
the center by means of a ball-type joint (FIG. 7). An increase of
the pressure transmitted can thus be achieved depending on the
distance of the chambers of both fluids to the center, without
needing to change the cross section of the chambers, though without
jeopardizing the possibility of being able to combine both effects.
Furthermore, if the two lines are placed diametrically opposed to
one another, and the attachment parts between the discs or pistons
of each line are in turn rigidly attached to one another, as shown
in FIG. 7, the same effect is achieved as with the previously
described U-shaped part, i.e., on one hand the reverse line
operation is achieved, thus simplifying the system control
electronics, and on the other hand the fluid 2, once it is
depressurized, is displaced from the corresponding chambers thereof
without needing auxiliary pumping, in cases in which the fluid 1
enters under very little pressure.
[0027] The splitting of chambers can be applied to all types of
traditional pressure exchangers developed today. There particularly
exists another type of traditional pressure exchangers, which are
mentioned perhaps because they are the most distinguished of all of
them, which are based on the same operating principle but
consisting of a cylinder with a series of inner conduits through
which the fluids pass, the pressures being exchanged. They further
have the particularity that the actual cylinder rotates about its
own axis. The chambers of this type of exchanger can also be split
to obtain the advantages herein explained.
SCPEs with Telescopic Chambers
[0028] These are SCPEs in which in order to transmit pressures the
chambers are telescopic and push one another, rather than the
rigidly attached double disc or piston system. FIG. 8 shows a
schematic depiction thereof.
SCPEs with Bellows-Type Chambers
[0029] These are SCPEs in which in order to transmit pressures the
chambers are bellows-type chambers and push one another, rather
than the rigidly attached double disc or piston system. FIG. 9
shows a schematic depiction thereof.
SCPEs with Membrane-Type Chambers
[0030] These are SCPEs in which the chambers in each line are
arranged such that those corresponding to the fluid to be
pressurized have rigid walls, and those of the fluid which yields
its pressure are membrane-type chambers, the latter being included
within the rigid wall type. FIG. 10 shows a schematic depiction
thereof.
SCPEs with Mixed Chambers
[0031] Obviously any of the possible arrangements (piston-type,
telescopic, bellows-type or membrane-type) can be combined such
that the chambers corresponding to one of the fluids can have one
arrangement and the chamber corresponding to the other fluid can
have a different arrangement.
[0032] Two of the possible combinations are depicted in FIGS. 11
(piston-type chambers/telescopic chambers) and 12 (telescopic
chambers/bellows-type chambers).
Multistage SCPEs
[0033] Multistage SCPEs consist of the splitting the chambers of
the fluid the pressure of which is yielded into several chambers,
which may or may not be used depending on the available pressure of
the fluid, by means of a valve system, thus being able to transmit
the most homogenous pressure possible to the fluid to be
pressurized, as shown in FIG. 13.
[0034] They can also be arranged such that the chambers which are
split are the chamber of the fluid to be pressurized, thus
pressurizing it at different pressures depending on the needs at
all times.
[0035] By means of the aid of an auxiliary tank, all the chambers
can be filled continuously so as to allow opening auxiliary
chambers midway through if the feed pressure changes, maximally
exploiting the energy of the pressurized fluid, as shown in FIG.
14.
[0036] Both FIGS. 13 and 14 depict multistage SCPEs with
piston-type chambers, but they can obviously also be provided with
telescopic, bellows-type, membrane-type or mixed chambers. They are
further depicted with the different chambers by way of concentric
and overlapping cylinders, but they can obviously be arranged with
any possible geometry provided that the pressurized fluid pushes
through all the chambers in the same direction.
[0037] FIG. 15 depicts a multistage SCPE with a circular
arrangement, which allows the aided reverse operation, as explained
above. For those applications in which either the pressure at which
the fluid the pressure of which is yielded must be returned once it
has been depressurized, or the starting pressure of the fluid to be
pressurized is variable, or both, with multistage SCPEs with a
circular arrangement, or with other arrangements and the U-shaped
tube system also described above, the control system can adjust the
stages that must start operating also depending on these
pressures.
[0038] Finally, it is also possible to complement the system with
auxiliary pumping and a speed variator to keep the pressure of the
fluid to be pressurized completely constant, controlling all this
from the electronic control system. If the pressurized fluid comes
from pumping, the speed variator can be placed in said pumping.
Variable Section SCPEs (VSSCPEs)
[0039] Another interesting possibility regarding the design of
SCPEs rests on their being able to have a variable section in any
of the fluid chambers thereof fluid (one, several or all). To that
end, it is essential for the piston, the actual chambers, or both,
to be able to have variable sections. Both possibilities are
described below.
Variable Section Pistons
[0040] These are pistons which have a section that changes along
the piston stroke. To that end, the chamber on which they are
housed must have a variable cross section.
[0041] The pistons must be designed such that their section can
increase or decrease, maintaining their own rigidity and the seal
of their attachments with the walls of the corresponding chamber
thereof. To that end, any type of mechanical or pneumatic system,
or a combination thereof, can be used.
[0042] FIGS. 16 and 17 depict the starts and the ends of the stroke
of a variable section piston. For the sake of simplicity, a
piston-type exchanger with a single line has been considered.
[0043] Since the section of the piston gradually reduces, the
pressure exerted on the fluid to be pressurized increases.
[0044] This type of VSSCPE can be applied in those situations in
which the distribution of pressures required by the system is known
beforehand.
Variable Wall Chambers
[0045] The distribution of pressures required by the system at all
times is generally not known a priori in most of the possible
applications, and the purpose is to attempt to modulate it
depending on the needs of the actual system.
[0046] Variable geometry chambers, either telescopic or piston-type
chambers, can be used in these cases, which can open or close and
even open at one end and close at the other. FIGS. 18 and 19 depict
a single-line piston-type VSSCPE with one of its chambers being a
variable section chamber.
[0047] Any type of mechanical or pneumatic system can be used to
move the walls of the variable section chambers. The use of
auxiliary telescopic cylinders which are filled with an
incompressible fluid and fixed at one end to the wall of the
chamber and at the other end to a fixed wall, as shown in FIGS. 18
and 19, may be particularly interesting. The walls of the chamber
are moved by extracting fluid from or introducing fluid into the
cylinders according to the needs of the system.
[0048] Telescopic cylinders could obviously be replaced with a
fixed chamber filled with an auxiliary fluid on which the actual
wall of the chamber of the VSSCPE would move like a piston (FIGS.
20 and 21).
[0049] As explained above, it is also possible to provide chambers
such that they can open at one end and close at the other end or
vice versa (FIGS. 22 and 23).
[0050] It is important to point out that the walls of the chambers
can move with very little force while the corresponding chamber is
not loaded, therefore this would be the ideal time to do it.
However, in certain applications it may be of interest to move them
during the stroke of the piston, when the chamber is loaded, though
to that end it is necessary to exert a greater force.
[0051] Finally, the possibility of using a membrane or elastic
material so that a telescopic chamber opens or closes for the
purpose of preventing the need for the piston to have a variable
section (FIGS. 24 and 25) should also be mentioned.
Control of the Speed of the Piston
[0052] An additional advantage of considerable interest is that the
VSSCPE can be designed such that the speed of the piston is
constant, except in a small initial span in which it must be
accelerated to the desired speed. The energy transfer performance
is thus optimized since it is not used for an unnecessary
acceleration of the double or single disc or piston. FIG. 26
depicts a possible design for this purpose, which consists of
providing the chamber with one of the fluids of an initial variable
section span, during which the piston accelerates until reaching
the design speed, at which time the straight span is reached, and
the speed is kept constant since the system is designed so that at
that time the force exerted on the piston by the fluid the pressure
of which is yielded is equal to the force exerted by the fluid to
be pressurized thereon plus losses due to friction corresponding to
the design speed.
[0053] There is another way to design it to keep the speed of the
piston constant which is explained in FIGS. 27 and 28, and it
prevents the piston from having to be a variable section piston. As
can be seen, the chamber has a section step, and again it is
designed to reach the desired speed of the piston in the initial
span with a larger section. In this case, the piston would have the
possibility of being separated into two or more parts, such that
during the first span it is kept rigidly attached and during the
second span it separates. This could be done with any type of
mechanical system.
[0054] Obviously, it is also possible to provide systems in which
the initial acceleration of the piston is done by means of any
other mechanical, electric, magnetic or pneumatic system
imaginable, and even systems in which the piston accelerates while
the gas is entering the chamber, such that the pressure to overcome
is minimal.
Batteries of Exchangers
[0055] As occurs with traditional pressure exchangers, SCPEs having
any of the presented arrangements can be arranged in series (FIG.
29), or in parallel (FIG. 30). Likewise, when the pressure surges
which are sought are very high, mixed systems with pumps can be
arranged to increase the pressure of the pressurized fluid and/or
the pressure of the fluid to be pressurized at the inlet and/or at
the outlet of the pressure exchanger (FIG. 31), without
jeopardizing the fact that they can also be arranged in series or
in parallel.
Control Electronics
[0056] Regarding the control electronics of the valves, a card with
a processor can be assembled in situ, or signals can be sent to a
central computer controlling them. In the case of multistage SCPEs,
the control system will be more complex as it must regulate the
valves depending on the inlet and/or outlet pressures of the two
fluids involved.
Number of Lines per SCPE
[0057] Regarding the number of lines necessary per SCPE, there will
usually be at least two in number but depending on the ranges of
outputs and pressures worked with in each case, it may be
appropriate to increase the number to three or more lines, although
it may be appropriate for a line to not have the same length, since
it would be used to achieve the most constant outlet pressure
possible of the starting pressurized fluid.
[0058] In addition, on certain occasions it may be appropriate for
only one line to be arranged, considerably simplifying the system
control electronics.
Geometry of the Chambers
[0059] Finally, regarding the geometry of the lines of the
chambers, in any of the longitudinal arrangements they can be
straight, curved and even circular, and the cross section thereof
may be circular, elliptical, triangular, square, rectangular,
polygonal or any imaginable cross section.
Alignment
[0060] Finally, the SCPEs in any of the arrangements put forth can
be aligned in any possible way (horizontally, vertically or
angled). FIGS. 32 and 33 show multistage SCPEs with vertical
alignments, with the pressurized fluid pushing upwardly (FIG. 32)
or downwardly (FIG. 33).
Design of the Attachments in Piston-Type SCPEs
[0061] To reduce the effect of the bending stresses in piston-type
SCPEs, another possibility consists of reinforcing the attachments
of the rod, rods, sheets or central solid parts with the discs or
pistons, as shown in FIGS. 34 and 35.
Advantages of the Invention Over the Prior State of the Art
[0062] As explained above in the general description of the
invention, the essential advantages of the SCPEs are the following:
[0063] each of the fluids only passes through the corresponding
chamber thereof, such that said fluids cannot be mixed. This means
that this system can be used to pump any type of fluid transmitting
the necessary energy to another different fluid (which can be clean
water, and even distilled water, or any other fluid that is found
to cause less damage to the electric pump units), and then
exchanging the pressures thereof. Very heavy and non-corrosive
fluids can also be chosen to reduce the size of the pumping and
storage installations. This will entail an increase of the
performance achieved as well as a considerable savings in
maintenance costs and even in installation design and execution
costs [0064] they allow changing the cross sections of the
chambers, thus changing the pressure transmitted to the fluid to be
pressurized. This is another considerable advantage of this
invention, since it allows choosing between pumping a greater
output at a lower height, or a lower output at a greater height,
which makes it possible to choose in each case the type of pump
offering the best performance and better exploiting small pressure
differences or small level differences of large amounts of fluid,
as will be described below [0065] they allow assuring and
harmonizing aided reverse line operation, either by means of the
U-shaped tube with telescopic sides and fixed base filled with
incompressible fluid or by means of the arrangement of
diametrically opposed curved lines, and attachment parts between
pistons of each line rigidly attached to one another [0066] they
allow exploiting the energy of the level differences of any
material in any storage form by means of the also innovative method
described below, and furthermore, [0067] SCPEs with telescopic,
bellows-type, membrane-type or mixed chambers prevent the problem
of bending stresses occurring in the discs or pistons rigidly
attached to one another, reduce the space that the chambers occupy
by half, and can be designed so that the reverse operation does not
have to be aided, since it is possible to play with the elasticity
of the membranes or design telescopic or bellows chambers such that
they always automatically return to their starting position with
enough force to drag the fluid, once depressurized, therein [0068]
multistage SCPEs transmit the most homogenous pressure possible to
the fluid to be pressurized, despite the variations of the pressure
of the pressurized fluid at the inlet, or they pressurize it at
different pressures depending on the needs at all times [0069] for
those applications in which either the pressure at which the fluid
the pressure of which is yielded must be returned once it has been
depressurized, or the starting pressure of the fluid to be
pressurized is variable, or both, with multistage SCPEs with a
circular arrangement, or with other arrangements and the U-shaped
tube system, the control system can adjust the stages that must
start operating also depending on these pressures [0070] in
piston-type SCPEs, the reinforcement of the attachments of the rod,
rods, sheets or central solid parts with the discs or pistons
reduces the problem of bending stresses [0071] VSSCPEs open up the
possibility of modulating the working pressures of split-chamber
pressure exchangers, which will allow better adapting to the needs
of a large amount of possible applications [0072] an additional
advantage that is of considerable interest is that VSSCPEs can be
designed such that the speed of the piston is constant, except in a
small initial span in which it must be accelerated to the desired
speed. The energy transfer performance is thus optimized since it
is not used for an unnecessary acceleration of the double or single
disc or piston.
DESCRIPTION OF THE DRAWINGS
[0073] Fifty drawings are attached to aid in explaining the
operation, arrangements and applications of SCPEs. Reference is
made thereto from several different points of this document,
explaining in each case the content thereof. In any case, the
relation and content of each drawing is provided below:
[0074] FIG. 1: Diagram of traditional pressure exchangers
[0075] FIG. 2: Process of a desalination plant with traditional
pressure exchangers
[0076] FIG. 3: Diagram of a split-chamber pressure exchanger
[0077] FIG. 4: SCPEs with different cross sections
[0078] FIG. 5: Vertical assembly of SCPEs
[0079] FIG. 6: Aided reverse operation of SCPEs
[0080] FIG. 7: Assembly of SCPEs with curved lines
[0081] FIG. 8: SCPEs with telescopic chambers
[0082] FIG. 9: SCPEs with bellows-type chambers
[0083] FIG. 10: SCPEs with membrane-type chambers
[0084] FIG. 11: SCPEs with mixed chambers
(piston-type/telescopic)
[0085] FIG. 12: SCPEs with mixed chambers
(telescopic/bellows-type)
[0086] FIG. 13: multistage SCPEs
[0087] FIG. 14: multistage SCPEs with auxiliary tank
[0088] FIG. 15: multistage SCPEs with circular arrangement
[0089] FIG. 16: Diagram of a line of a piston-type VSSCPE with a
fixed section chamber and the other chamber being a variable
section chamber with fixed walls, the stroke of the piston
starting
[0090] FIG. 17: Diagram of a line of a piston-type VSSCPE with a
fixed section chamber and the other chamber being a variable
section chamber with fixed walls, the stroke of the piston
ending
[0091] FIG. 18: Diagram of a line of an immobile wall VSSCPE with
telescopic pneumatic cylinders for securing the walls, the stroke
of the piston starting
[0092] FIG. 19: Diagram of a line of an immobile wall VSSCPE with
telescopic pneumatic cylinders for securing the walls, the stroke
of the piston ending and after having modified the section of the
immobile wall chamber
[0093] FIG. 20: Diagram of a line of an immobile wall VSSCPE with
an outer chamber filled with fluid for securing the walls, the
stroke of the piston starting
[0094] FIG. 21: Diagram of a line of an immobile wall VSSCPE with
an outer chamber filled with fluid for securing the walls, the
stroke of the piston ending and after having modified the section
of the immobile wall chamber
[0095] FIG. 22: Diagram of a line of an immobile wall VSSCPE with
two telescopic pneumatic cylinders for securing the walls, which
allow the movement and the rotation of the walls of one of the
chambers, the stroke of the piston starting
[0096] FIG. 23: Diagram of a line of an immobile wall VSSCPE with
two telescopic pneumatic cylinders for securing the walls, which
allow the movement and the rotation of the walls of one of the
chambers, the stroke of the piston ending and after having modified
the geometry of the immobile wall chamber
[0097] FIG. 24: Diagram of a line of an immobile wall VSSCPE with
telescopic pneumatic cylinders for securing the walls, fixed
section pistons and elastic span in the immobile wall chamber, the
stroke of the piston starting
[0098] FIG. 25: Diagram of a line of an immobile wall VSSCPE with
telescopic pneumatic cylinders for securing the walls, fixed
section pistons and elastic span in the immobile wall chamber, the
stroke of the piston ending and after having modified the section
of the immobile wall chamber
[0099] FIG. 26: Diagram of a line of a VSSCPE in which one of the
chambers has an initial variable section span to accelerate the
piston
[0100] FIG. 27: Diagram of a line of a VSSCPE in which one of the
chambers has an initial smaller section span to accelerate the
piston during the piston acceleration phase
[0101] FIG. 28: Diagram of a line of a VSSCPE in which one of the
chambers has an initial smaller section span to accelerate the
piston during the constant piston speed phase once the two parts of
the piston are set
[0102] FIG. 29: Assembly in series of the SCPEs
[0103] FIG. 30: Assembly in parallel of the SCPEs
[0104] FIG. 31: Mixed systems of electric pump units and SCPEs
[0105] FIG. 32: Multistage SCPEs in vertical arrangement, with the
pressurized fluid pushing upwardly
[0106] FIG. 33: multistage SCPEs in vertical arrangement, with the
pressurized fluid pushing downwardly
[0107] FIG. 34: Reinforcements in the attachments of the rod, rods,
sheets or central solid parts with the discs or pistons (I)
[0108] FIG. 35: Reinforcements in the attachments of the rod, rods,
sheets or central solid parts with the discs or pistons (II)
[0109] FIG. 36: Step-wise operation of the multistage SCPE (I)
[0110] FIG. 37: Step-wise operation of the multistage SCPE (II)
[0111] FIG. 38: Step-wise operation of the multistage SCPE
(III)
[0112] FIG. 39: Step-wise operation of the multistage SCPE (IV)
[0113] FIG. 40: Pumping system with SCPEs
[0114] FIG. 41: Pumping system for wells or collection boxes with
SCPEs
[0115] FIG. 42: Exploitation of the geographic level differences of
a river
[0116] FIG. 43: Exploitation of the level difference of tides (high
tide)
[0117] FIG. 44: Exploitation of the level difference of tides (low
tide)
[0118] FIG. 45: Exploitation of the level difference of tides with
an elastic wall chamber (high tide discharging fluid from the
chamber)
[0119] FIG. 46: Exploitation of the level difference of tides with
an elastic wall chamber (high tide when the discharge of fluid from
the chamber ends)
[0120] FIG. 47: Exploitation of the level difference of tides with
an elastic wall chamber (low tide loading of fluid into the chamber
starts)
[0121] FIG. 48: Exploitation of the level difference of tides with
an elastic wall chamber (low tide loading fluid into the chamber
ends)
[0122] FIG. 49: Exploitation of the level difference of tides with
an elastic wall chamber and continuous feed system
[0123] FIG. 50: Process of a desalination plant with SCPEs
DETAILED EXPLANATION OF AN EMBODIMENT OF THE INVENTION
[0124] FIGS. 36 to 39 diagrammatically depict the operating process
of a multistage SCPE, with seven concentric chambers located on the
side of the pressurized feed fluid.
[0125] FIG. 36 shows the first of the lines starting to be filled
and the second one starting to drain. The pressure gage at the
inlet of the pressurized fluid records a high pressure of the
fluid, therefore the valve feeding the concentric chambers closes
and therefore only pressurized fluid enters the central cylinder.
The valve system in the gray box in the figure allows the passage
of pressurized fluid to the first line and prevents the passage
thereof to the second line. Likewise, said system allows draining
said already depressurized fluid from the second line. In addition,
since the valve feeding the concentric chambers in the valve system
shown in the figure in the second line is closed, it allows
draining the fluid from the central cylinder but not from the
remaining cylinders. The fluid contained in the remaining cylinders
therefore exits through the conduit leading it to the auxiliary
tank.
[0126] The system therefore works by raising the fluid of the first
line and lowering the fluid of the second line. The auxiliary tank
furthermore feeds the concentric cylinders of the first line, since
the valves giving access to each of them open. The level in the
auxiliary tank does not drop, since it is in turn fed by the
depressurized fluid of the concentric cylinders of the second line.
For this reason such tank could even be eliminated and converted
into a flow-off.
[0127] At a certain time, the lines work up to a mid point as
depicted in FIG. 37. At said time, the pressure gage detects a drop
in the pressure of the pressurized feed fluid, and for this reason
the control system immediately calculates how many chambers must
start working in order to keep the pressure transmitted to the
fluid to be pressurized as constant as possible depending on said
drop. In the case that is shown, the control system would activate
four of the concentric cylinders, as shown in FIG. 38. Obviously,
since the concentric cylinders are filled with fluid depressurized
coming from the auxiliary tank, these cylinders are automatically
pressurized with the single opening and closing of the
corresponding valves, the fluid therefore not losing energy while
it fills the concentric cylinders if they are empty.
[0128] After this time, since the concentric cylinders of the
second line continue discharging into the auxiliary tank and the
latter only feeds the remaining ones of the first line, the tank
starts to fill and therefore overflow through the spillway,
discharging the fluid into the corresponding drain, as shown in
FIG. 39, in which the lines are assumed to be reaching the end of
their stroke.
[0129] Once the end of the stroke has been reached, it is necessary
to start discharging the first line and loading the second line
according to a process similar to that herein shown.
[0130] The process is repeated indefinitely
INDUSTRIAL APPLICATIONS OF THE INVENTION
[0131] Due to the described important advantages provided by the
invention, the range of industrial applications opened up is very
wide. The most relevant ones are listed below:
[0132] 1) As a pumping system in general (FIG. 40), since it has
the following advantages as it has split chambers:
[0133] the fluid which is used to pump (fluid 2 in FIG. 40) does
not have to be the same as that to be pumped (fluid 1), which is
extremely important and applicable in infinite cases. In other
words, whether dealing with wastewater, viscous fluids, toxic
fluids, hazardous fluids, seawater, chemical products, concrete,
turbid water or any type of fluid imaginable, even fluids with
solids in suspension, clean water pumps and even pumps working with
distilled water or any other fluid which has been proven to damage
the electric pump units less can be used with exchangers of this
type (very heavy and non-corrosive fluids can be chosen to reduce
the size of the pumping and storage installations). This will
involve an increase of the performances achieved as well as
enormous savings in the maintenance and even design and execution
of the installations
[0134] a choice can be made between pumping greater output at a
lower height, or a lower output at a greater height; the type of
pump giving a better performance can thus be chosen in each case.
Furthermore, this enables exploiting in a much better manner small
pressure differences or small level differences of large amounts of
fluid
[0135] 2) in hydroelectric power stations, by inserting these SCPEs
a choice can also be made between centrifuging greater output at a
lower height, or a lower output at a greater height, which allows
choosing in each case the type of turbine giving a better
performance. Obviously, and as has been forth in the previous
point, the fluid to be centrifuged does not have to be the same,
which also involves another important advantage since fluids can
again be chosen in a customized manner to reduce the manufacture
and maintenance costs of power stations
[0136] 3) regarding submersed or vertical pumps in wells or deep
collection boxes, they can be replaced with surface pumps with
SCPEs having long attachments between the discs of the order of the
length of the well or collection box, such that some chambers are
located on the surface and other at the bottom of the well or
collection box (FIG. 41). The chambers of the surface are fed with
any fluid, again chosen to optimize the manufacture and maintenance
costs of the installations. This system can be assembled in two
stages, such that in the first stage the water or fluid to be
pumped is raised to the surface and in the second stage its
pressure is raised to the desired pressure. The system can also be
assembled with the lower chambers of the SCPE in dry conditions,
either in the same well or collection box above the water level,
using a small auxiliary feed pumping, or in a contiguous tight
collection box
[0137] 4) the natural level differences of a river can also be
exploited, placing the SCPEs in one of the banks of the river at a
certain depth, which SPCEs are feed from an intake coming from the
river, and by playing with the sections of the chambers the
pressure of the fluid to be pumped (water from the river itself for
irrigators, country estates, housing developments, municipalities
or nearby industries, or any other fluid to be pumped for any type
of process) is raised. The water of the river enters one of the
chambers of the SCPEs with a certain pressure due to the depth at
which the SCPEs are placed and/or to a prior feed pumping.
Furthermore, by suitably placing the intake, the kinetic energy of
the river current can also be exploited. At the outlet, this water
is again discharged into the river through a conduit which moves it
downstream such that it falls by gravity or at least the height to
be pumped is reduced (FIG. 42). If there is enough geographic level
difference, a turbine can also be placed to exploit the residual
energy of the water prior to returning it to the river bed
[0138] 5) another application consists of exploiting the level
difference caused in seas, rivers and river mouths by tides. Water
can be taken directly from the sea or from a beach well when the
tide is high and, after pumping it if necessary or driving it
downwardly to increase its pressure, it feeds the SCPEs, and it is
then stored in a basin or tank (FIG. 43) in order to wait until the
tide ebbs and it is then returned to the sea by means of a pumping
if necessary, which will be provided with a check valve at the
outlet to prevent the water from circulating in a reverse direction
when the tide is high (FIG. 44). While the tide is low, if the
plant is to be kept operating, it will be necessary to pump or pump
with a higher surge the feed water of the exchangers. To optimize
the system, two pumps can be assembled in parallel or a pump can be
assembled in parallel with a simple tube, according to the design
needs
[0139] 6) another way to exploit the level difference of the tides
consists of using a fluid installed inside a chamber with elastic
walls (membrane-type chamber). The chamber is placed inside the sea
firmly attached by its base to the seabed, as shown in FIGS. 45 to
48. A pipe extending to solid ground emerges from the bottom of the
chamber, which pipe has a shut-off valve. While the tide rises, the
chamber is filled with the fluid and with the shut-off valve
closed, such that the pressure of the fluid increases. When the
tide is high, the shut-off valve opens and the chamber starts to be
drained, feeding the SCPEs (FIG. 45). If necessary, an additional
pumping prior to the inlet to the exchangers would be added, as
shown in FIG. 45. The process continues until the chamber is
completely drained (FIG. 46). The depressurized fluid at the outlet
of the exchangers has been stored in a basin or tank, to discharge
it or pump it again to the chamber when the tide ebbs (FIG. 47),
until the chamber is filled again (FIG. 48). If it is necessary to
work continuously, the exchangers can be fed the rest of the time
by means of pumping from the fluid storage basin or tank (FIG. 49).
A very heavy fluid can be chosen to optimize the dimensions of the
system, or even the seawater itself or any other fluid, such as
fresh water or even distilled water can be used to reduce the wear
with the use of the installation. It is also important to emphasize
the environmental advantage of this system compared to other
developed systems for exploiting the level difference caused by
tides (which normally involves constructing dams or other works
with a considerable environmental impact), as the environmental
impact is zero since the chamber with elastic walls is submersed.
To end this point, it must simply be added that rigid but
telescopic walls, or rigid walls with the upper part moving
upwardly and downwardly like a piston rather than elastic walls
could be placed
[0140] 7) obviously the system for exploiting the level differences
caused by tides with the system of a chamber with elastic walls set
forth in the previous application could be extrapolated to any
other level difference occurring over time of any type of material
imaginable, whatever the state in which it is, as is the case of
reservoirs, tanks for drinking water, irrigation water or for any
other fluid in any type of industrial process, and even any type of
silo, tank or place in which solids are stored or pooled, since, in
short, what this system does is exploit the fact that in a certain
place there is something which is loaded and unloaded over time and
the weight of which is exploited to press a fluid feeding the
SCPEs. It will occasionally be suitable for the fluid to be used to
be a gas so that it occupies less when it is compressed and storage
capacity is not lost. The system can be electronically controlled
by means of a computer to optimize the times in which the pressure
of the fluid inside the chamber is exploited, since in many cases
the levels do not change from maximum to minimum and vice versa,
and therefore it may be suitable to exploit the turning points from
being filled to being drained and vice versa
[0141] 8) The geographic levels existing in sanitation networks and
especially rainwater networks can also be exploited, because since
the latter case involves clean (rain) water, it is easier to handle
as a fluid for feeding the SCPEs. The mode of operation is similar
to that described for rivers, i.e., an intake is made at a point of
the network which feeds the exchangers, which are at a lower level
to achieve a certain pressure at the inlet, and, once used to
increase the pressure of the other fluid (any fluid which is to be
pumped), it is again discharged into the network downstream, either
completely by gravity or with the aid of a pumping
[0142] 9) the residual pressure of multiple fluids involved in
industrial processes, and generally any imaginable residual
pressure can be similarly exploited with this system
[0143] 10) another very important application is that relating to
fluid distribution networks. The two probably most important cases
are drinking water and irrigation water distribution networks.
Generally, in a distribution network, the fluid is introduced at
one or several points, and there are multiple outlets throughout
it. However a minimum pressure is to be arranged at the most
unfavorable point of the network, in many spans of the network
there are overpressures which sometimes even force placing
pressure-reducing valves. Furthermore, the output circulating at
the start of the distribution of the network does not need to be
complete for the first supplies, but rather it could very well be
considerably reduced such that only that necessary one remains to
attend to said first supplies. Thus, by means of the corresponding
pipe network, a part of the fluid could be collected at the start
of the network, it could be used to feed SCPEs, and finally it
could be returned to the distribution network, downstream and with
less pressure, particularly with the pressure necessary at that
point of the network. The fluid which is placed on the side of the
exchangers, which can be the fluid itself of the network to supply
high points thereof or the header tanks, or any other fluid which
it is necessary to pump (for example, wastewater in the case of
drinking water distribution networks) is thus pressurized
[0144] 11) any possible combination of the described applications;
for example, by means of an integrated control of the system,
seawater desalination plants could well use a combination for
exploiting the level differences of tides, the level differences of
a possible river running or opening out close to the location of
the plant, nearby drinking water or irrigation water distribution
networks, sanitation and/or rainwater networks, or any other fluid
with residual pressure in any type of industrial process existing
in the area. FIG. 50 depicts the diagram of a seawater desalination
plant with SCPEs (which obviously also corresponds to that of a
brackish water desalinator but without the advantage in most cases
of the level differences caused by tides). For the sake of
simplicity, it has been depicted with a single storage basin or
tank, assuming that level differences of tides, rivers or rainwater
networks are exploited, and that therefore they are later
discharged back into the sea, but obviously if other exploitations
(supply, sanitation, industrial networks, etc) are combined, a
basin or tank for each fluid that must be returned to a different
place must be made
[0145] 12) finally, if in the described pressure there is a
residual pressure available after it has been used in the multiple
fluid pumping uses which may be necessary, there is obviously
always the possibility of using it to centrifuge the fluid in
question and producing electric power. Furthermore, by inserting
SCPEs again, the execution and maintenance costs as well as the
yield of the plants can be considerably improved, as has been
described in point 2 above
[0146] There is a large variety of arrangements of SCPEs, as has
been set forth above. For the sake of simplicity, single exchangers
with parallel lines have been depicted in all the figures, but in
each application the optimal arrangement thereof will be chosen
depending on the design parameters of the installation.
* * * * *