U.S. patent application number 13/058904 was filed with the patent office on 2011-06-09 for pump device.
This patent application is currently assigned to SPX FLOW TECHNOLOGY NORDERSTEDT GMBH. Invention is credited to Christian Huhnke, Henning Ladiges.
Application Number | 20110135514 13/058904 |
Document ID | / |
Family ID | 39883770 |
Filed Date | 2011-06-09 |
United States Patent
Application |
20110135514 |
Kind Code |
A1 |
Huhnke; Christian ; et
al. |
June 9, 2011 |
Pump Device
Abstract
A pump device includes a pulsator as a drive element for a main
pump head which is situated in a delivery line and the working
chamber of which is provided with a suction-side non-return valve
and a pressure-side non-return valve. The working chamber of the
pulsator is connected via an oscillation line, which is filled with
delivery medium, to the working chamber of the main pump head in
such a way that the pulsator sucks delivery medium out of the
delivery line and into the working chamber of the main pump head,
or presses delivery medium out of the working chamber, in an
oscillating fashion. A ventilation valve is provided for
ventilating the working chamber of the pulsator, and the
ventilation line is a time-controlled valve and/or a
pressure-controlled double-seat valve. A device may be provided for
introducing a liquid into the working chamber of the pulsator
and/or the oscillation line.
Inventors: |
Huhnke; Christian; (Bad
Bramsted, DE) ; Ladiges; Henning; (Uetersen,
DE) |
Assignee: |
SPX FLOW TECHNOLOGY NORDERSTEDT
GMBH
Nordestedt
DE
|
Family ID: |
39883770 |
Appl. No.: |
13/058904 |
Filed: |
August 14, 2009 |
PCT Filed: |
August 14, 2009 |
PCT NO: |
PCT/EP2009/005928 |
371 Date: |
February 14, 2011 |
Current U.S.
Class: |
417/395 ;
417/404 |
Current CPC
Class: |
F04B 53/08 20130101;
F04B 43/067 20130101; F04B 43/06 20130101; F04B 53/06 20130101 |
Class at
Publication: |
417/395 ;
417/404 |
International
Class: |
F04B 43/06 20060101
F04B043/06; F04B 35/02 20060101 F04B035/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 14, 2008 |
EP |
08014528.7 |
Claims
1. A pump device comprising a pulsator as a drive element for a
main pump head which is located in a delivery line, the working
chamber thereof including a suction-side non-return valve and a
pressure-side non-return valve, the working chamber of the pulsator
being connected, via a transfer line filled with fluid to be
delivered, to the working chamber of the main pump head such that
the pulsator one of sucks fluid to be delivered in an oscillating
manner from the delivery line into the working chamber of the main
pump head and forces said fluid to be delivered out of the working
chamber, a venting valve being provided for ventilating the working
chamber of the pulsator, wherein the venting valve is one of a
time-controlled valve and a pressure-controlled double-seat valve,
and wherein a device is provided for introducing a fluid into the
working chamber of at least one of the pulsator and the transfer
line.
2. The pump device as claimed in claim 1, wherein the working
chamber of the pulsator is connected via a further venting valve to
the suction side of the delivery line.
3. The pump device as claimed in claim 1, wherein the working
chamber of the pulsator is connected via a further venting valve to
the pressure side of the delivery line.
4. The pump device as claimed in claim 1, wherein the working
chamber of the pulsator is connected via a further venting valve to
a refill reservoir for compensating for leakage losses in the
working chamber of at least one of the pulsator and the transfer
line.
5. The pump device as claimed in claim 1, wherein the working
chamber of the pulsator is connected via a further venting valve to
a collection container for collecting and subsequently returning
fluid to be delivered produced during ventilation.
6. The pump device as claimed in claim 1, wherein the pump device
has a refill reservoir for refilling fluid to be delivered, which
is acted upon by a pressure which substantially corresponds to the
system pressure.
7. The pump device as claimed in claim 1, wherein the transfer line
is provided with a cooling system.
8. The pump device as claimed in claim 1, wherein the pulsator is
arranged above the main pump head.
9. The pump device as claimed in claim 1, wherein the transfer line
in at least one portion is subdivided into at least two parallel
subsections.
10. The pump device as claimed in claim 9, wherein the volume of
the subsections of the transfer line extending parallel and/or the
volume of the transfer lines extending parallel is respectively at
least as great as the swept volume of the pulsator.
11. The pump device as claimed in claim 9, further comprising
control valves are provided for at least partially opening and
closing the subsections of the transfer line or the parallel
transfer lines.
12. The pump device as claimed in claim 1, wherein the main pump
head has at least two suction-side non-return valves arranged in
parallel.
13. The pump device as claimed in claim 12, wherein the cross
section of the line receiving the suction-side non-return valve
which is downstream relative to the direction of flow during the
compression phase, is greater than the cross section of the line
receiving the other suction-side non-return valve.
14. The pump device as claimed in claim 1, further comprising a
separating piston arranged in the transfer line.
15. The pump device as claimed in one of the preceding claim 1,
wherein the pulsator is a dual-acting pulsator, the device further
comprising two pump circuits controlled in opposing directions.
16. The pump device as claimed in claim 1, wherein the pulsator is
configured as a dual-acting pulsator, one side thereof being
configured as a drive element for the main pump head, and the other
side thereof being acted upon by a pressure which substantially
corresponds to the system pressure.
17. The pump device as claimed in claim 1, wherein the pulsator is
designed to have a diaphragm or tubular diaphragm.
18. The pump device as claimed in claim 1, wherein the pulsator is
designed to have a piston or plunger.
Description
[0001] The invention relates to a pump device having a pulsator as
a drive element for a main pump head which is located in a delivery
line and the working chamber thereof is provided with a
suction-side non-return valve and a pressure-side non-return valve,
as claimed in the preamble of claim 1.
[0002] Within the meaning of the present disclosure of the
invention, a "diaphragm pulsator" is understood in that it
corresponds to a piston diaphragm pump which does not necessarily
have suction-side and pressure-side non-return valves, but instead
generally has all the features of a piston diaphragm pump. The
person skilled in the art understands by "piston diaphragm pump" a
piston pump coupled to a diaphragm, the displacement of the piston
being transmitted via a hydraulic coupling to the diaphragm. In the
same manner as piston diaphragm pumps, diaphragm pulsators may also
comprise, in particular, a preferably position-controlled diaphragm
refill device and/or ventilating device for the hydraulic fluid, as
is disclosed, for example, in EP 0 085 725 A1.
[0003] In particular, the invention relates to a pump device having
a pulsator, in particular a diaphragm pulsator, as a drive element
for a main pump head which is located in a delivery line and the
working chamber thereof is provided with a suction-side non-return
valve and a pressure-side non-return valve. The working chamber of
the pulsator is directly connected, via a transfer line filled with
fluid to be delivered, to the working chamber of the main pump head
such that the pulsator sucks fluid to be delivered in an
oscillating manner from the delivery line into the working chamber
of the main pump head or forces said fluid to be delivered out of
the working chamber. The pump device according to the invention is
particularly well-suited for delivering suspensions, such as for
example mixtures of biomass and supercritical water and, in
particular, for high pressures and temperatures.
[0004] Pumps of this type are disclosed in EP 0919724 B1 and EP
1898093 A1. In this connection, a main pump head located in the
delivery line is driven by a further pump head which is denoted as
a pulsator. Such a pump device is also denoted as a "remote head"
pump. Such pump devices are typically used for pumping fluids with
a high proportion of solids and at high temperatures. The known
pumps may not be easily used, however, with particularly aggressive
media for delivery, such as for example supercritical aqueous
solutions, in particular where processes are present with a very
high throughput at high temperatures and high pressures.
[0005] The object of the invention is to provide a pump device of
the aforementioned type which may be used for pumping aggressive
media for delivery at a high temperature and which nevertheless
operates with a high degree of reliability at low cost, which is
why in particular the contamination of the pulsator by solid
particles should be avoided.
[0006] This object is achieved by a pump device according to the
features of at least one of the independent claims. Advantageous
embodiments of the invention are provided in the dependent
claims.
[0007] According to an embodiment of the invention, a pump device
is provided having a pulsator as a drive element for a main pump
head which is located in a delivery line and the working chamber
thereof is provided with a suction-side non-return valve and a
pressure-side non-return valve, the working chamber of the pulsator
being connected, via a transfer line filled with fluid to be
delivered, to the working chamber of the main pump head, such that
the pulsator sucks fluid to be delivered in an oscillating manner
from the delivery line into the working chamber of the main pump
head or forces said fluid to be delivered out of the working
chamber, a venting valve being provided for ventilating the working
chamber of the pulsator, the venting valve being a time-controlled
valve and/or a pressure-controlled double-seat valve and/or a
device being provided for introducing a fluid into the working
chamber of the pulsator and/or the transfer line.
[0008] The use of a time-controlled valve and/or a
pressure-controlled double-seat valve has the advantage that the
time in which the valve is open for ventilation is able to be kept
very short, whereby undesirable secondary flows may be avoided
which could result in increased contamination of the pulsator by
solid particles.
[0009] The introduction of fluid into the working chamber of the
pulsator and/or the refilling of fluid to be delivered into the
working chamber for compensating for losses, for example as a
result of ventilating the working chamber, has the advantage that
fluid does not have to be compensated by the driven main pump head,
and thus no solid particles are transported from the main pump head
to the pulsator.
[0010] According to the invention, the fluid may be water and/or
fluid to be delivered and/or another suitable fluid.
[0011] According to the invention, the time-controlled and/or
pressure-controlled venting valve may be a single-seat valve and/or
a double-seat valve.
[0012] According to the invention, the device for introducing a
fluid into the working chamber of the pulsator and/or the transfer
line may comprise a time-controlled and/or pressure-controlled
refill valve and/or a refill reservoir.
[0013] According to the invention, the time-controlled and/or
pressure-controlled refill valve and/or venting valve may be
time-controlled and/or pressure-controlled so that after a start-up
phase of the process the refill valve and/or venting valve is
closed and/or the upper limit value for closing the time-controlled
and/or pressure-controlled refill valve and/or venting valve is
increased after a start-up phase of the process and/or after a
start-up phase of the process the lower limit value is reduced for
closing the time-controlled and/or pressure-controlled refill valve
and/or venting valve.
[0014] Preferably, the pressure to which the refill reservoir is
subjected substantially corresponds to the pressure in the working
chamber of the pulsator.
[0015] According to an embodiment of the invention, the refill
valve may be a time-controlled and/or pressure-controlled valve
between the working chamber and the refill reservoir.
[0016] According to the invention, the working chamber of the
pulsator may be connected via the and/or a further venting valve to
the suction side of the delivery line.
[0017] According to the invention, therefore, the suction side of
the delivery line may advantageously be arranged above the venting
valve for automatic ventilation.
[0018] Alternatively or additionally, according to the invention
the working chamber of the pulsator may be connected via the and/or
a further venting valve to the pressure side of the delivery
line.
[0019] According to the invention, the venting valve may be
force-controlled in combination with a return pump, in particular
in a time-controlled manner.
[0020] Alternatively or additionally, according to the invention
the working chamber of the pulsator may be connected via the and/or
a further venting valve to a refill reservoir for compensating for
leakage losses in the working chamber of the pulsator and/or the
transfer line.
[0021] Alternatively or additionally, according to the invention
the working chamber of the pulsator may be connected via the and/or
a further venting valve to a collection container for collecting
and possibly subsequently returning fluid to be delivered which is
produced during the ventilation.
[0022] According to the invention, the valve may be time-controlled
and/or pressure-controlled such that it is closed at least above a
specific pressure.
[0023] The pulsator produces in the working chamber a continuously
alternating pressure at a compression phase and a suction phase. In
order to prevent a weakening of the flow from the transfer line for
driving out possibly sucked-in solid particles, ventilation should
not be carried out at least above a specific pressure in the
working chamber in order to prevent a drop in pressure in the
working chamber, even though this may be small, and thus a
reduction in the flow from the transfer line.
[0024] According to the invention, the valve may be time-controlled
and/or pressure-controlled such that it is closed at least below a
specific pressure.
[0025] Alternatively or additionally, ventilation should be avoided
below a specific pressure in the working chamber of the pulsator,
as due to the drop in pressure, even though this may be small,
greater suction power and thus a greater flow would be produced in
the transfer line, which could suck in more solid particles into
the transfer line. Thus the valve should be closed at least below a
specific pressure in the working chamber.
[0026] Preferably, the ventilation only takes place in the time
periods between the suction phase and the compression phase, where
there is a substantially small flow or no flow at all of the fluid
to be delivered into the transfer line. As a result, the flow of
solid particles into the transfer line may be prevented.
[0027] According to an embodiment of the invention which may be
additionally configured with the above-mentioned features of the
cited embodiments of the invention, a pump device is provided with
a pulsator as a drive element for a main pump head which is located
in a delivery line and the working chamber thereof is provided with
a suction-side non-return valve and a pressure-side non-return
valve, the working chamber of the pulsator being connected, via a
transfer line filled with fluid to be delivered, to the working
chamber of the main pump head such that the pulsator sucks fluid to
be delivered in an oscillating manner from the delivery line into
the working chamber of the main pump head or forces said fluid to
be delivered out of the working chamber, the pump device having a
refill reservoir for refilling fluid to be delivered, which is
acted upon by a pressure which substantially corresponds to the
system pressure.
[0028] According to the invention, in all embodiments of the
invention the transfer line may be provided with a cooling
system.
[0029] According to the invention, in all embodiments of the
invention the pulsator may be arranged above the main pump head.
Additionally or alternatively, according to the invention the
transfer line may be oriented to fall from the pulsator toward the
main pump head. Such embodiments of the invention have the
advantage that gravity additionally counteracts contamination by
solid particles through the transfer line into the pulsator.
[0030] According to the invention, the transfer line may be
provided with a sink as a receiving chamber for solid particles in
the fluid to be delivered.
[0031] According to the invention, the working chamber of the
pulsator may be at least occasionally acted upon by a compensating
medium for compensating for leakage losses.
[0032] According to an embodiment of the invention, which may be
additionally configured with the above-mentioned features of the
cited embodiments of the invention, a pump device is provided with
a pulsator as a drive element for a main pump head which is located
in a delivery line and the working chamber thereof is provided with
a suction-side non-return valve and a pressure-side non-return
valve, the working chamber of the pulsator being connected, via a
transfer line filled with fluid to be delivered, to the working
chamber of the main pump head such that the pulsator sucks fluid to
be delivered in an oscillating manner from the delivery line into
the working chamber of the main pump head or forces said fluid to
be delivered out of the working chamber, the transfer line in at
least one portion being subdivided into at least two parallel
subsections.
[0033] According to the invention, the transfer line may also be
divided up over its entire path, i.e. for example two or more
parallel transfer lines may be provided.
[0034] These embodiments of the invention have the advantage that
by providing a corresponding control, for example, the at least two
subsections are opened in the suction phase and in the compression
phases at least one subsection (where there are two subsections,
preferably alternately one and then the other subsection) is closed
at least partially and preferably completely, at least during part
of the compression phase, in order to prevent deposits of solid
particles in the subsections by the resulting higher outflow
velocity in the other subsection(s).
[0035] According to the invention, the volume of the subsections of
the transfer line extending parallel and/or the volume of the
transfer lines extending parallel may respectively be at least as
great as, or preferably greater than, the swept volume of the
pulsator.
[0036] This development of the invention has the advantage that an
escape of solid particles into the remaining transfer line and/or
the pulsator may in all likelihood be prevented.
[0037] According to the invention, control valves may be provided
for at least partially opening and closing the subsections of the
transfer line and/or the parallel transfer lines.
[0038] According to the invention, a sensor system may be provided
in order to synchronize the timed control of the control valves
with the respective phase position of the pulsator diaphragm. For
example, a sensor and/or switch may be provided which operates the
control valve in at least one end position of the diaphragm of the
pulsator. Alternatively or additionally, a sensor and/or switch may
be provided for the other diaphragm position, in order to operate
the control valve. Alternatively, the control valves could also
only be displaced into a closed position and/or partially closed
position during one part of the compression phase. It might also be
conceivable during a compression phase to close, at least
partially, different control valves in succession.
[0039] According to the invention, in the region in front of the
main pump head, the transfer line may preferably be subdivided into
a plurality of lines arranged parallel, preferably two lines
arranged parallel, which at least partially and preferably
completely may be able to be at least partially closed by a
time-controlled and/or pressure-controlled valve.
[0040] The time control and/or pressure control should be adjusted
so that during the suction phase all lines are open as long as
possible, so that the flow is distributed to the different parallel
lines, whilst in the compression phases a portion of the line is
alternately subjected to the full pressure and thus a substantially
greater flow velocity. As a result, contamination of solid
particles in the transfer line should be reliably avoided.
[0041] According to an embodiment of the invention which may be
configured with the aforementioned features of the cited
embodiments of the invention, a pump device is provided with a
pulsator as a drive element for a main pump head which is located
in a delivery line and the working chamber thereof is provided with
a suction-side non-return valve and a pressure-side non-return
valve, the working chamber of the pulsator being connected, via a
transfer line filled with fluid to be delivered, to the working
chamber of the main pump head such that the pulsator sucks fluid to
be delivered in an oscillating manner from the delivery line into
the working chamber of the main pump head or forces said fluid to
be delivered out of the working chamber, the main pump head having
at least two suction-side non-return valves arranged in parallel
(16, 161).
[0042] This embodiment of the invention has the advantage that
during the compression phase in the portion of the line between the
outlets of the two suction-side non-return valves, a greater flow
velocity is produced so that the risk of the entry of solid
particles into the transfer line from the suction-side non-return
valve which is downstream relative to the flow direction is reduced
during the compression phase.
[0043] According to the invention, the cross section of the line
receiving the suction-side non-return valve which is downstream
relative to the direction of flow during the compression phase, is
greater than the cross section of the line receiving the other
suction-side non-return valve.
[0044] This is the preferred execution of this embodiment according
to the invention, as then more solid particles are conveyed by the
line, which provides increased safety relative to the contamination
of solid particles in the transfer line. Alternatively, the cross
sections of the two lines could also be the same size or more than
two lines and a corresponding number of suction-side non-return
valves could be provided. Also conceivable is a larger cross
section of the suction-side non-return valve which is upstream
relative to the flow direction during the compression phase, which
still provides an advantage, albeit small, relative to the
embodiments with only one suction-side non-return valve.
[0045] According to an embodiment of the invention which may
additionally be configured with the above-mentioned features of the
cited embodiments of the invention, a pump device is provided with
a pulsator as a drive element for a main pump head which is located
in a delivery line and the working chamber thereof is provided with
a suction-side non-return valve and a pressure-side non-return
valve, the working chamber of the pulsator being connected, via a
transfer line filled with fluid to be delivered, to the working
chamber of the main pump head such that the pulsator sucks fluid to
be delivered in an oscillating manner from the delivery line into
the working chamber of the main pump head or forces said fluid to
be delivered out of the working chamber, a separating piston being
arranged in the transfer line.
[0046] These embodiments of the invention have the advantage that
the separating piston prevents solid particles thereon from passing
through the transfer line from the main pump head to the
pulsator.
[0047] According to the invention, the aforementioned embodiments
of the pump device according to the invention may be configured
with a dual-acting pulsator and two pump circuits controlled in
opposing directions.
[0048] According to an embodiment of the invention, which may be
additionally configured with the aforementioned features of the
cited embodiments of the invention, a pump device is provided with
a pulsator as a drive element for a main pump head which is located
in a delivery line and the working chamber thereof is provided with
a suction-side non-return valve and a pressure-side non-return
valve, the working chamber of the pulsator being connected, via a
transfer line filled with fluid to be delivered, to the working
chamber of the main pump head such that the pulsator sucks fluid to
be delivered in an oscillating manner from the delivery line into
the working chamber of the main pump head or forces said fluid to
be delivered out of the working chamber, the pulsator being
configured as a dual-acting pulsator, one side thereof being
configured as a drive element for the main pump head and the other
side thereof being acted upon by a pressure which substantially
corresponds to the system pressure.
[0049] Such embodiments of the invention with a dual-acting
pulsator for driving two mutually controlled pump circuits are
preferred as, consequently, uniform delivery may be achieved.
Furthermore, the pulsator at high suction pressures of, for
example, 250 bar may be driven by a drive designed for
substantially lower pressures, if for example a dual-acting piston
is used, which only has to overcome the pressure difference between
the pressure during the compression phase in the one pulsator half
and the pressure during the suction phase in the respective other
pulsator half. This advantage also applies to dual-acting pulsators
for driving only one pump circuit, if the other side of the
pulsator which does not drive the pump circuit is acted upon by
pressure. Advantageously, in embodiments of the invention with a
refill reservoir for the diaphragm control chamber(s) of the
pulsator, the refill reservoir is acted upon by a pressure which
corresponds approximately to the system pressure, so that also
during the refill process, which takes place in a valve-controlled
manner, if the diaphragm reaches its rear mechanical abutment, the
drive is not subjected to a greater pressure than the difference in
pressure between the suction phase and compression phase, and thus
does not have to be of larger size, and the diaphragm is also not
destroyed on the flow channels of its rear mechanical abutment.
[0050] According to the invention, a diaphragm position-controlled
refill device and/or ventilation device for hydraulic fluid may be
provided in the pulsator as, for example, is disclosed in EP 0 085
725 A1.
[0051] According to the invention, for compensating for leakage
losses in the diaphragm control chamber compensating medium may be
present in a refill reservoir that is connected to the diaphragm
control chamber via a valve, the refill reservoir being acted upon
by a pressure which is greater than atmospheric pressure.
[0052] This embodiment of the invention has the advantage that the
pulsator may be driven by a drive (for example hydraulically,
mechanically and/or pneumatically, for example a piston drive), the
power thereof only having to overcome the pressure difference
between the suction side and the pressure side. Moreover, by
pressure acting on the refill reservoir for compensating for
leakage losses in the diaphragm control chamber, an impact on the
drive, for example the piston, may be prevented. Advantageously,
said pressure in the refill reservoir may correspond approximately
to the system pressure. According to a further advantageous
embodiment of the invention, a pressure control adapted to the
system pressure by means of a control circuit may be provided in
the refill reservoir, as is disclosed, for example, in EP 1 898 093
A1.
[0053] According to the invention, the pulsator may be designed to
have a diaphragm or tubular diaphragm.
[0054] According to the invention, the pulsator may be designed to
have a piston or plunger.
[0055] A basic idea of the invention, therefore, is also that the
pulsator acts upon a main pump head, which in principle is
configured as a piston pump head but without a piston being
required. In this manner, a standard component which is suitable
for high temperatures and pressures may be used as a pump head
which, by combining with a standard diaphragm pulsator, as a whole
represents a cost-effective alternative to the known solutions, the
principle of a "remote head" pump being maintained. Wear is also
reduced as particles possibly present in the fluid to be delivered
do not come into contact with the working chamber of the pulsator,
as the fluid in the transfer line is only moved to and fro within
the range of the pump stroke, and is mixed only slightly with
freshly suctioned fluid. The pulsator may be designed to have a
diaphragm or tubular diaphragm and to have a piston or plunger.
When the pulsator is a diaphragm pulsator, particles do not enter
the diaphragm. As high temperatures in the fluid to be delivered
are also reduced over the course of the transfer line, diaphragm
pulsators with cost-effective plastics diaphragms, for example made
of PTFE, may also be used at high pressures and high temperatures
in the delivery line. Thus the pump devices according to the
invention are particularly well suited for delivering biomass
during the production of biofuel.
[0056] A further advantage is that, due to the ventilation, gases
from the fluid to be delivered or air inlets may not collect in the
pump chamber of the pulsator but are returned to the process.
Preferably, to this end, the inlet in the suction-side delivery
line is located above the venting valve so that the gases
automatically escape from the working chamber. Alternatively, there
may be forced ventilation, for example with a time-controlled
and/or pressure-controlled valve.
[0057] In order to relieve the diaphragm pulsator still further in
terms of temperature, a preferred development of the invention is
that the transfer line is provided with a cooling system.
[0058] It also proves advantageous that the transfer line is
orientated to fall from the diaphragm pulsator to the main pump
head. The particles thus remain in the region of the main pump head
and are passed back into the delivery line.
[0059] Alternatively, it may be advantageous that the transfer line
is provided with a sink as a receiving chamber for solid particles
in the fluid to be delivered. Thus in the transfer line a region is
provided which is located below the working chamber of the
diaphragm pulsator, so that the particles collect there due to
gravity and do not enter the working chamber of the pulsator.
[0060] It is expedient if the working chamber of the pulsator is
acted upon by a compensating medium for compensating for leakages,
so that a through-flow of the transfer line and a migration of
solid particles to the pulsator are prevented.
[0061] In order to protect the pulsator even further against solid
particles from the fluid to be delivered, a further advantageous
embodiment of the invention is to arrange a separating piston in
the transfer line. As a result of this measure, the part of the
transfer line associated with the pulsator is separated from the
part which is associated with the main pump head.
[0062] A low driving power is achieved by a dual-acting pulsator
and two pump circuits controlled in opposing directions being
present, which is advantageous particularly with the use of
recirculation processes at high suction pressures.
[0063] The invention is described in more detail hereinafter with
reference to exemplary embodiments. In the drawings,
schematically:
[0064] FIG. 1 shows a vertical section through a first embodiment
of a pump device;
[0065] FIG. 1A shows a vertical section corresponding to FIG. 1
through a further pump device according to the invention,
comprising a dual-acting pulsator and two pump circuits controlled
in opposing directions.
[0066] FIG. 2 shows a circuit diagram of a pump configuration made
up of two pump devices according to FIG. 1 according to the
invention;
[0067] FIG. 3 shows features of further embodiments of a pump
device according to the invention.
[0068] FIG. 4 shows a circuit diagram corresponding to FIG. 2 of an
alternative pump configuration according to the invention;
[0069] FIG. 5 shows a circuit diagram corresponding to FIG. 2 of a
further alternative pump configuration according to the
invention;
[0070] FIG. 6 shows a circuit diagram corresponding to FIG. 2 of a
further alternative pump configuration according to the
invention;
[0071] FIG. 7 shows a circuit diagram corresponding to FIG. 2 of a
further alternative pump configuration according to the
invention;
[0072] FIG. 8 shows features of further embodiments of a pump
device according to the invention.
[0073] FIG. 9 shows features of further embodiments of a pump
device according to the invention.
[0074] FIG. 10 shows a circuit diagram of a pump configuration made
up of two pump devices according to FIG. 1 according to the
invention;
[0075] FIG. 11 shows a P-V-diagram of the time curve of the
pressure of the pump over the swept volume with an indication of
possible refilling during the compression phase.
[0076] FIG. 12 shows a P-V-diagram of the time curve of the
pressure of the pump over the swept volume with an indication of
possible refilling during the suction phase.
[0077] In the description of the exemplary embodiments, the
following reference numerals are used: [0078] 1 Pump device [0079]
4 Connection (for a refill reservoir) [0080] 5 Pressure side (of
the delivery line) [0081] 6 Delivery direction [0082] 7 Connection
(for the transfer line) [0083] 8 Connection (for ventilation)
[0084] 9 Venting valve [0085] 10 Diaphragm pulsator [0086] 11 Main
pump head [0087] 12 Transfer line [0088] 12' Transfer line [0089]
121 Subsection of the transfer line [0090] 122 Subsection of the
transfer line (arranged in parallel with the subsection 121 of the
transfer line) [0091] 123 Control valve (preferably a
pressure-controlled or time-controlled shut-off valve) [0092] 124
Control valve (preferably a pressure-controlled or time-controlled
shut-off valve) [0093] 13 Inlet [0094] 14 Outlet [0095] 15 Suction
side (of the delivery line) [0096] 16 Suction-side non-return valve
[0097] 161 Suction-side non-return valve (arranged in parallel with
the suction-side non-return valve 16) [0098] 17 Pressure-side
non-return valve [0099] 18 Working chamber (of the main pump head)
[0100] 20 Working chamber (of the diaphragm pulsator) [0101] 21
Delivery fluid [0102] 22 Control inlet (of the main pump head)
[0103] 23 Cooling jacket [0104] 24 Solid particles [0105] 25
Portion (in the transfer line) [0106] 26 Diaphragm [0107] 27
Diaphragm control chamber [0108] 28 Piston [0109] 281 Disk [0110]
29 Motor [0111] 30 Refill reservoir [0112] 31 Valve [0113] 32
Separating piston [0114] 33 Region (on side of main pump head)
[0115] 34 Region (on side of diaphragm pulsator) [0116] 35
Displacement direction of separating piston [0117] 36 Collection
container [0118] 37 Refill valve of diaphragm control chamber
[0119] 38 Hydraulic pump [0120] 39 Venting valve of diaphragm
control chamber
[0121] According to FIG. 1 a pump device 1 has a diaphragm pulsator
10 serving as a pulsator, a main pump head 11 and a transfer line
12. The main pump head 11 has an inlet 13 and an outlet 14 for
installation in a delivery line, the pressure side thereof being
denoted by 5 and the suction side thereof by 15. A suction-side
non-return valve 16 is present on the inlet side (suction side) and
a pressure-side non-return valve 17 is present on the outlet side
(pressure side). The direction of delivery is identified by the
arrow 6.
[0122] Structurally, the main pump head 11 corresponds namely to a
pump head of a piston pump. However, it does not have a piston. Its
working chamber 18 is instead directly connected to a working
chamber 20 of the diaphragm pulsator 10 via the transfer line 12.
The diaphragm pulsator 10 is provided with a connection 7 for the
transfer line 12. Moreover, a connection 8 is present for
ventilation by a venting valve 9 (FIG. 2) and a connection 4 for a
refill reservoir 30 (FIG. 2). Thus the oscillating stroke of the
diaphragm pulsator 10 causes the delivery in the main pump head 11
via the fluid column in the transfer line 12.
[0123] The transfer line 12 is filled with delivery fluid 21. It
passes via a control inlet 22 of the main pump head 11 to the
working chamber 20 of the diaphragm pulsator 10. The transfer line
12 is provided with a cooling system, which is formed by a cooling
jacket 23 acted upon by coolant. In this manner, there may be a
temperature reduction from, for example, approximately 360.degree.
C. at the main pump head 11, as it typically has the biomass to be
delivered in biofuel production, to approximately 100.degree. C. on
the diaphragm pulsator 10.
[0124] As the transfer line 12 contains the delivery fluid 21,
which may also comprise solid particles 24, a portion is present 25
in the transfer line 12 which falls from the diaphragm pulsator 10
to the main pump head 11, and which directly discharges into the
working chamber 18 of the main pump head 11. At its lowest point,
the transfer line 12 is thus located at the level of the working
chamber 18 of the main pump head 11. The solid particles 24 remain,
as a result, due to gravity in the working chamber 18 of the main
pump head 11 and do not enter the working chamber 20 of the
diaphragm pulsator 10. They are instead supplied to the
pressure-side delivery line 5.
[0125] The diaphragm pulsator 10 has a diaphragm 26 which is
hydraulically controlled via a diaphragm control chamber 27. As a
diaphragm material, preferably PTFE is suitable. Alternatively,
elastomers, metallic materials or composite materials may also be
used. The diaphragm control chamber 27 is acted upon by a piston
28, which is driven mechanically, for example by a motor 29 (FIG.
2) and/or hydraulically and/or pneumatically, for example, by
alternately subjecting the chambers adjacent to the disk 281 to
pressure. For compensating for leakages, a refill reservoir 30 is
present, filled with a compensation medium which, via a controlled
valve 31 (FIG. 2), discharges compensation medium into the working
chamber 20 of the diaphragm pulsator 10. The supply is denoted in
FIG. 2 by 4.
[0126] With reference to FIG. 1 and FIG. 2, the function of the
pump device is described hereinafter. The configuration shown in
FIG. 2 has a dual-acting pulsator with two pump devices, as
illustrated in FIG. 1. The pump devices are arranged in parallel in
two branches A, B controlled in opposing directions. Initially, a
pump process is described with reference to one branch. In an
initial state, the piston 28 is moved into the diaphragm control
chamber 27 and the diaphragm 26 bulges out into the working chamber
20 of the diaphragm pulsator 10. The transfer line 12 and the
working chamber 18 of the main pump head 11 are completely filled
with delivery fluid. The suction-side non-return valve 16 and the
pressure-side non-return valve 17 are closed.
[0127] If the piston 28 is extended, this causes a flattening of
the diaphragm 26 and a negative pressure in the working chamber 20
of the diaphragm pulsator 10. The negative pressure acts via the
transfer line 12 in the working chamber 18 of the main pump head
11, so that the suction-side non-return valve 16 opens and delivery
fluid 21 is sucked in from the suction side 15 of the delivery
line. With the subsequent opposing stroke of the piston 28, with
the bulging of the diaphragm 26, pressure is produced in the
working chamber 20 of the diaphragm pulsator 10 which acts via the
transfer line 12 on the working chamber 18 of the main pump head
11. The pressure causes a closing of the suction-side non-return
valve 16 and an opening of the pressure-side non-return valve 17,
so that delivery fluid 21 is pumped into the pressure side 5 of the
delivery line. By the oscillating movement of the piston 28 a
continuous delivery takes place in this manner.
[0128] By the control of two main pump heads 11 in opposing
directions, by means of the dual-acting pulsator 10, which is
preferably designed in the manner of a diaphragm, the pumping and
suction processes with the two circuits A and B are superimposed so
that, in particular, with recirculation processes at a high system
pressure and a relatively small difference in pressure between the
suction line and pressure line only a small amount of power is
required for the drive. Alternatively, each main pump head 11 may
be controlled by a single-acting pulsator in the same or opposing
direction.
[0129] In FIG. 3, a portion of a transfer line 12' is illustrated
as a detail of a second exemplary embodiment. For separating the
fluid column in the transfer line 12' a separating piston 32
mounted longitudinally displaceably along the double arrow 35 is
arranged in the transfer line 12'. Solid particles 24, which are
possibly present, thus remain in a region 33 on the main pump head
11 side and may not enter a region 34 on the diaphragm pulsator
side.
[0130] FIG. 1A shows an embodiment with a dual-acting pulsator.
FIG. 1A substantially corresponds to the embodiment shown in FIG.
1, in principle the pump device of FIG. 1 being present twice, and
being driven by a common piston 28. The dual-acting pulsator is
shown in extremely simplified fashion in FIG. 1A, i.e. without a
drive and without a hydraulic reservoir, and the refill valves are
acted upon by pressure. The dual-acting piston 28 describes an end
position (to the right the diaphragm 26 bulges out, i.e. the
compression stroke and/or the compression phase is complete; to the
left the diaphragm 26 is flattened, i.e. the suction stroke and/or
the suction phase is complete).
[0131] The embodiments shown in FIGS. 2, 4, 5 and 6 of the
invention substantially differ only by the different ventilation
and/or refilling. The same components and features are described
using the same reference numerals. Regarding the exemplary
embodiments of FIGS. 4, 5 and 6, therefore, reference is made to
the above description of the exemplary embodiment of FIG. 2, and
hereinafter only the differences from this embodiment of the
invention are described.
[0132] FIG. 2 shows an embodiment with ventilation into the suction
line 15. The refilling takes place from a pressure store 30 (with a
gas cushion) in a time-controlled and/or pressure-controlled manner
during the compression stroke of the pulsator. The graphic symbol
used for the valve 31 describes a controlled non-return valve, of
which the closing is prevented when activated. The pressure in the
refill reservoir 30 has to be greater than the system pressure. The
refill volumetric flow has to be greater than/the same as the
leakage flow of the ventilation process. A subsequent adjustment of
the storage pressure is recommended depending on the changing
system pressure. If required, manual control is also possible.
[0133] FIG. 4 shows an embodiment with ventilation in the pressure
line 5. The refilling takes place from a pressure store 30 (with a
gas cushion) in a time-controlled and pressure-controlled manner
during the suction stroke of the pulsator. The graphic symbol used
for the valve 31 describes a controlled non-return valve, of which
the opening is prevented when activated. The pressure in the refill
store 30 has to be greater than the suction pressure. The refill
volume flow has to be greater than/the same as the leakage flow of
the ventilation process. A subsequent adjustment of the storage
pressure is recommended depending on the changing suction pressure.
If required, manual control is also possible.
[0134] FIG. 5 shows an embodiment with ventilation into the refill
reservoir 30. The refilling takes place from a pressure store 30
(with a gas cushion) in a time-dependent manner. The symbol for the
refill valve 31 shows no specific function.
[0135] FIG. 6 shows an embodiment with ventilation into any storage
or collection container 36. The refilling takes place from a
pressure store 30 (with a gas cushion) in a time-dependent manner.
The symbol for the refill valve 31 shows no specific function.
[0136] FIG. 7 shows an embodiment of the invention of a pump device
with a single-acting pulsator. The ventilation and/or refilling may
take place according to the above-mentioned embodiments of the
invention, for example, according to FIG. 2, FIG. 4, FIG. 5 or FIG.
6. By way of example, the ventilation into the pressure line 5 is
shown as one of the possible variants.
[0137] In the embodiment of FIG. 7, instead of the single-acting
pulsator, a dual-acting pulsator could also be used, the side
thereof which is not used being acted upon by a pressure which
corresponds approximately to the system pressure, for example by
means of a pressure store. Thus the advantages of a refill medium
acted upon by pressure may be utilized for refilling into the
diaphragm control chamber. Moreover, the advantage of subjecting
the unused side of the dual-acting pulsator to pressure is that a
drive of smaller dimensions may be used, if high pressures of, for
example, 250 bar from the pump head driven by the pulsator have to
be overcome.
[0138] FIG. 8 shows a possible configuration of the main pump head
11 of pump devices according to the invention. On the suction side
of the main pump head two suction-side non-return valves 16, 161
are provided which may also have different sizes. This embodiment
has the advantage that during the compression stroke of the
pulsator a greater flow velocity is produced in the line portion
between the two suction-side non-return valves.
[0139] The transfer line 12 has a gradient toward the suction-side
non-return valves 161, 16. During suctioning, the suction flow
corresponding to the cross-sectional ratios is divided up between
the suction-side non-return valves 161 and 16. As a result, during
suctioning it is achieved that in the portion of the transfer line
between said two suction-side non-return valves there is a smaller
flow than might be the case if the entire suctioned quantity were
to be suctioned only through the suction-side non-return valve
16.
[0140] During the compression stroke, the entire quantity of fluid
delivered by the pump flows through the transfer line. This has the
result that fluid flows through the transfer line which, as a
whole, is oriented more toward the suction-side non-return valve
16.
[0141] This flow could ensure that the deposits are instead
repeatedly delivered back by the main flow.
[0142] FIG. 9 shows a possible configuration of the transfer line
12 of pump devices according to the invention. The transfer line is
subdivided in at least one portion into at least 2 subsections 121,
122, which are simultaneously used for suctioning by means of
controlled shut-off valves 123, 124 in the suction phases, and
alternately respectively opened and closed in the compression
phases in order to prevent deposits in the subsections 121, 122 of
solid particles thus produced by the higher outflow velocity.
[0143] The filling volume of each of the subsections 121, 122
should preferably be at least as great as, and preferably greater
than, the swept volume of the pulsator. As a result, solid
particles are prevented from entering behind the controlling
valves, by alternately closing in the compression phase.
[0144] In a first suction process, therefore, each subsection would
initially be filled with particles to a maximum extent of up to
half of its volume. The subsequently closed subsection would
possibly maintain this state. With a further suction process, the
subsection would then be completely filled with particles to a
maximum extent, before thorough rinsing would take place in the
compression phase.
[0145] In the embodiment shown in FIG. 9, time-controlled shut-off
valves 123, 124 are provided which should be synchronized by means
of sensor systems exactly with the respective phase position of the
pulsator diaphragm.
[0146] FIG. 10 shows a further embodiment of the invention. The
same parts are provided with the same reference numerals. Reference
is made to the description of the above-mentioned embodiments. In
FIG. 10, the pulsator is shown in slightly more detail, the drive
not being shown for the dual-acting piston 28. The path of the
hydraulic channels of the dual-acting pulsator is shown, in
particular, in more detail.
[0147] The pump device of FIG. 10 has two refill valves 37 of the
diaphragm control chamber which preferably are acted upon by a
pressure which corresponds approximately to the system pressure.
The pressure is provided by a hydraulic pump 38. Moreover, two
venting valves 39 are provided for ventilating the diaphragm
control chambers.
[0148] FIGS. 11 and 12 show schematic PV-diagrams which show the
time curve of the pump pressure over the swept volume. Starting at
the point on the left side below, seen very clearly here are the
steep flank of the rise in pressure during the compression phase,
the pressure fluctuations due to the valve kinematics, the
extension of the swept volume (highest pressure at maximum piston
velocity) and also the sharp decompression phase and suction phase.
(Note: in the present case, in both figures for reasons of clarity
the cycle has been shown clockwise).
[0149] The dotted line in FIG. 11 shows the required pressure level
and a possible time window for a controlled leakage refilling
process during the compression stroke. The average working pressure
of the pulsator set in the compression stroke (pD) is slightly
greater than the system pressure.
[0150] The dotted line in FIG. 12 shows the required pressure level
and a possible time window for a controlled leakage refilling
process during the suction stroke. During refilling during the
suction stroke, it is sufficient if the pressure level is slightly
above the suction pressure.
* * * * *