Note: Descriptions are shown in the official language in which they were submitted.
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UNDERGROUND WATER MANAGEMENT SYSTEM FOR MINES
The invention relates to an underground liquid management system for mines, a
waterworks comprising the liquid management system and an output system and a
method
for operating a liquid management system.
South Africa, South and Central America and various other countries and
regions
of the world, for example, have mines or pits which are disused or still in
operation and
which in some cases reach to very great depths (e.g. 2000 to 5000m). These
mines and
pits contain cavities at different levels. The cavities can in part already be
filled naturally
with water.
DE 103 61 590 Al discloses a pump storage station, in which a cavity which is
artificially created at least for the lower basin is used in a shaft
installation.
DE 195 13 817 B4 describes a pump storage station which is disposed in a pit
of
an existing or cleared open pit mine of a brown coal deposit. The depth of the
aforementioned pit is utilised in order to provide the storage basins, which
are required for
the pump storage station, with a corresponding height difference with respect
to each
other. At least the lower basin is disposed below the level of the surrounding
area. The
artificially constructed stores can be constructed by the excavated material
which occurs
during extraction of the brown coal deposit.
It is known from DE 100 28 41 to provide a hydroelectric power station as a
block-
like structural unit having a cylindrical basic shape which is located on the
ground surface
or is completely or partially embedded into the ground, in order to make hydro
power
useful in an artificial manner irrespective of natural ground topographies and
natural water
potentials. Two stores disposed one above the other are provided in the
artificially
constructed, closed structure. In a storage operation, water is pumped by
means of a pump
from the lower store into the upper store. In an energy generation operation,
the water is
guided back from the upper store into the lower store by a turbine, which is
disposed
between the stores, for electricity generation. The energy required for the
pump can be
provided by means of wind or solar energy plants or a geothermal unit.
The prior art thus demonstrates pump storage stations which are provided
merely
for energy generation, wherein the storage basins are provided for the most
part artificially
and separately in the ground. Only DE 103 61 590 Al proposes producing a lower
basin
of a pump storage station from an artificially created shaft installation.
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Therefore, it is an object of the present invention to provide a system which
in a
simple and cost-effective manner provides for comprehensive liquid management
(e.g.
water management) and is used not only for generating and storing energy but
also for
storing and cleaning liquids located in a mine.
This object is achieved by the subject matter of the independent claims. The
dependent claims develop the central idea of the invention in a particularly
advantageous
manner.
In accordance with a first aspect, an underground liquid management system for
mines is provided for generating and/or storing energy, storing and/or
cleaning liquids
(e.g. water and/or surface waters) located in the mine or its natural
surrounding area; thus
also comprising the reduction or removal of pollutants (inter alia also of
solids) from
liquids from the natural surrounding area. The term "liquid" is thus
understood hereinafter
to mean any liquid which passes naturally or artificially into the cavities of
the mine or is
located in the natural surrounding area of the mine, in particular groundwater
or surface
water (e.g. rainwater). The system has at least one first store which is
formed by a cavity
of the mine, and at least one second store. At least the bottom of the second
store is
disposed above that of the first store. In a particularly preferable manner,
the second store
is disposed above the first store. The underground liquid management system
also
comprises: at least one line, which connects the stores, for conducting the
liquid, at least
one pumping device for conveying the liquid through the lines from the first
store into the
second store, and a geothermal device for generating geothermal energy at
least for
operating the pump and preferably also for operating further components of the
system,
i.e., for the auxiliary power of the system, and optionally also for provision
to third parties,
that is e.g. by feeding the generated energy into an electricity network
(electrical energy)
or into a heat store (heat energy). The geothermal device can also be provided
for
generating heat or cooling energy, in order to utilise this e.g. for
surrounding residential or
industrial areas or in the mine itself; e.g. as a thermal power station/heat
pump or energy
system.
The system in accordance with the invention thus renders it possible in a
simple
and cost-effective manner to utilise already existing cavities of a mine
without undertaking
any further significant reconstruction measures for comprehensive liquid
management
(storing and/or cleaning liquids and solids and/or (simultaneously) generating
and/or
storing energy). The liquid management includes e.g. the return of the system
to its
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natural state, i.e., the renaturation of the mine and/or the liquids, in
particular the
groundwater and surface water. The liquid management also includes the
reduction of
contaminants both in the water (groundwater and surface water) and also in the
mine, i.e.,
the geological layers themselves. Furthermore, comprehensive groundwater
protection
thus also takes place, since the naturally present groundwater of a specific
geological layer
in the mine is cleaned and in particular not polluted further. In synergy with
the
environmentally sound system, the geothermal energy, i.e., ground heat, which
can be
accessed particularly effectively in mines owing to the depth thereof can be
utilised for
generating electrical energy and optionally also for generating heat and/or
cooling energy;
in particular for the operation of the pump of the liquid management system or
the mine
per se. Furthermore, generating energy from geothermal energy can reduce the
mine
operator's dependence upon external energy suppliers (e.g. for electricity,
heat, cooling
energy, ...), whilst at the same time at least this part of the energy supply
takes place with
sustainable (regenerative) energy.
Preferably, all or at least a large proportion of the stores to be used for
the
underground fluid management system are formed by cavities of the mine. In
this manner,
the additional provision of external tanks is no longer required and the
provision of the
liquid management system is simplified considerably and is cost-effective and
simple to
produce.
Preferably, cleaning stages are provided between and/or in the stores. In this
manner, contaminated liquids can be cleaned in an environmentally sound manner
and
even in the system itself. This leads to an effective and efficient reduction
of
contamination in all waters located in the mine, in particular to marked
groundwater
protection which also has a positive effect upon renaturation of the system.
The liquid in the stores can become contaminated e.g. by reason of the
material
(e.g. uranium) excavated in the mine or by the material used for mining (e.g.
mercury for
gold extraction). Contamination is thus present in a specific geological layer
or passes
through pollution of the groundwater or of other liquids (e.g. waters and
surface waters)
entering the system into this layer or it is present at least in the liquid
(e.g. groundwater)
located in the cavities.
Corresponding cavities which are used in accordance with the invention as
stores
are located in particular in mines in different groundwater reservoirs and/or
they pass
through a plurality of groundwater reservoirs. Groundwater reservoirs which
are
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sometimes also defined as aquifers are water-carrying, natural layers or rock
masses
having cavities which are suitable for guiding groundwater. Groundwater
reservoirs are
mutually separated or delimited geologically by means of water-impermeable
layers, the
so-called aquifuges. In general, the construction or opening of the mine
causes various
aquifers to be penetrated which frequently are flooded artificially or
naturally (with
groundwater) e.g. after the mine has been shutdown. Flooding of the mine
causes liquids
(in this case e.g. groundwater) e.g. from uranium-contaminated geological
layers to mix
with liquids/water from uncontaminated layers which results in all of the
liquid in the
mine becoming polluted unnecessarily.
In order to prevent this uncontrolled mixing of the water and therefore to
avoid
more significant damage to the groundwater and thus to the surrounding
ecosystem, the
aforementioned cleaning stages, in which a cleaning process can be conducted
for the
contaminated liquid, are preferably interposed or provided at suitable
locations. The
uncontrolled mixing of the water can also be avoided by suitable structural
separation
measures. In this manner, impurities e.g. in the groundwater can be removed or
at least
greatly reduced, so that long-term damage to the ecosystem is prevented and
the
groundwater can be rendered useable again for people and nature.
In order to achieve this, the cleaning stage preferably has at least one
filter device
for cleaning the liquid, preferably at least in or between stores,
particularly preferably at
least in or between stores in contaminated layers. The filter device can be
used to achieve
an increased reduction of contamination which in turn has a positive effect
upon the
groundwater and the purity/purification thereof, as the quality of the
groundwater can be
increased considerably by reason of the removed or at least greatly reduced
contamination.
For this purpose, the filter device can be connected on the one hand to the
pumping
device in a fluidic manner such that the liquid is cleaned during a pumping
process of the
pumping device, preferably that the liquid is cleaned as it is conducted
through the lines.
On the other hand, in addition or alternatively at least one store can be
filled at least
partially with a porous material which then forms the filter device. For this
purpose,
reference is also made to the water-storing and water-cleaning system in
accordance with
EP 2 058 441 Al, the subject matter of which can also be used in a comparable
manner as
a filter device in stores of the present invention.
The filter device can also comprise e.g.: at least one barrier layer, which is
aligned
substantially horizontally in the store, for the purpose of lengthening the
seepage path of
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the liquid, wherein the barrier layer is provided with at least one passage
for the fluid, and
located above and below the barrier layer is porous material; and a collecting
vessel for
collecting cleaned liquid, which extends from the bottom of the store in a
substantially
vertical direction upwards. The water collecting vessel comprises at least
below the
5 lowermost barrier layer at least one opening, through which the liquid
can flow or seep.
In a development of the last-named filter device, a pumping device can be
disposed
in the water collecting vessel. In this case, a line from the pumping device
extends in a
vertical direction upwards at least out of the collecting vessel (and thus
consequently into
the corresponding store). The cleaned liquid can thus be supplied once again
to the
cleaning circuit, in order to increase further the extent to which the liquid
is cleaned. In a
preferred embodiment, the aforementioned line extends additionally also out of
the store
itself. This conveniently ensures that, on the one hand, the liquid is
returned to the
cleaning circuit and that, on the other hand, the cleaned liquid is provided
in other stores
or to the outside environment.
Alternatively or in addition, in a development of the last-named filter device
the
collecting vessel can also be disposed in such a manner that it is disposed
above a
connection opening which leads to an underlying store, wherein the collecting
vessel
substantially surrounds the connection opening. Therefore, a second underlying
cleaning
device can be connected to or provided on the cleaning device, which increases
the
effectiveness of the cleaning stage. Moreover, by providing turbines in the
connection
opening, it is additionally possible to generate energy if the liquid is
preferably optionally
drained from the collecting vessel into the underlying store.
Furthermore, the cleaning stage can comprise at least one cleaning device for
raising or lowering the pH value of the liquid. This cleaning device has
preferably at least
one chalk layer, through which and/or along which the liquid is guided for the
purpose of
changing the pH value. In this manner, it is possible to raise e.g.
groundwater, which in
some regions has a particularly low pH value (of ca. 2-3), to a desired level,
particularly
preferably to a neutral pH value range. However, it is also feasible for water
or other
liquids having any current pH value to be raised or lowered to a desired value
which
deviates from the current pH value. Therefore, the pH value of the liquid can
also be
adapted in addition to, or for the purpose of, cleaning it.
Furthermore, if a single store extends over at least one uncontaminated layer
and
one contaminated layer, an artificial barrier can be provided in the store
extending over the
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layers, which extends preferably along an aquifuge which separates the
contaminated layer
from the uncontaminated layer. In this way, contaminated liquid can be
reliably prevented
from mixing unnecessarily with uncontaminated liquid, even if a store extends
over a
plurality of groundwater reservoirs. This also results in improved groundwater
protection,
in particular because uncontaminated groundwater does not come into contact
unnecessarily with contaminated (ground or surface) water or other
contaminated liquids.
In one development, the barrier can also be provided with a through-opening,
in the flow
path of which there is disposed a turbine for generating electricity, and
which can be
closed by means of a stop valve.
The lines in general extend in a particularly preferred manner in a
substantially
vertical direction upwards out of the respective store into at least one store
disposed above
it and/or out of the mine. The phrase "out of the mine" means in particular
that the stated
line extends as far as the surface of the earth and optionally beyond it into
the surrounding
area and is thus preferably accessible from outside.
Further preferably, the geothermal device or the geothermal energy is the
primary
energy source, wherein, however, in addition further, in particular renewable,
energy
sources, such as e.g. a wind energy plant for wind energy, a solar energy
plant for solar
energy and/or a pump storage station for flow energy, and the like can
additionally also be
provided. This ensures a sufficient supply of energy to the underground liquid
management system at all times, wherein this is provided by means of renewable
energies,
as a result of which the environment is not additionally polluted. The energy
generated by
the regenerative energy sources - but also each externally supplied energy -
can be stored
by storing the liquid in a store situated in a higher location and can be
converted at any
time into energy (e.g. electricity) by optionally draining the liquid into a
store situated in a
lower location by driving a turbine disposed in the flow path (pump storage
station).
It is also possible for a store to be formed as a liquid supply or liquid
reservoir, in
which liquid is collected and provided, e.g. for provision for the operation
of the mine
itself or, if the liquid is water, as an industrial water or drinking water
reservoir or even for
renaturation of the system and the surrounding area thereof It is thus
possible that for the
operation of the mine or after it has been shutdown, liquid (in particular
groundwater
and/or surface water) can be obtained from a dedicated source for provisioning
in any
form. This prevents natural resources of the environment, such as e.g. water
from
surrounding rivers or lakes, from being used, which serves to conserve the
environment on
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account that there are no unnecessary interventions therein, and can also
promote a
renaturation of the mine, its surrounding area and the cleaned liquids. By
virtue of the fact
that the mine is self-sufficient, it is also no longer dependent upon a public
water supply,
which is of considerable importance in particular in areas with scarce water
resources,
extends the scope of application or is at least more attractive from an
economic point of
view.
In a particularly preferred manner, the liquid is water, preferably
groundwater
and/or surface water or water provided artificially for the purpose of
flooding the mine.
As already described above, it can be further used or reused in a variety of
ways; e.g. for
renaturation purposes, wherein this is promoted further by the reduction in
contamination.
Preferably, separating walls or separating layers consisting of clay or clay
rock are
provided in the underground liquid management system at the location where
contaminated liquids are present or flow through, in order to clean liquids
which are
contaminated in particular by radioactive substances. In this manner, an
effective cleaning
device is provided for liquids which are contaminated in particular by
radioactive
substances.
In accordance with a further aspect, the invention describes a waterworks for
providing drinking water and industrial water which comprises the underground
liquid
management system as a water management system and also an output system for
providing the water from the water management system.
A method for operating a liquid management system is also disclosed.
The invention will now be described with reference to exemplified embodiments
which are illustrated in the Figures of the accompanying drawings, in which
Figure 1 shows an underground liquid management system in accordance with a
first
exemplified embodiment,
Figure 2 shows an underground liquid management system in accordance
with a
second exemplified embodiment,
Figure 3 shows an underground liquid management system in accordance
with a
third exemplified embodiment,
Figure 4 shows an underground liquid management system in accordance
with a
fourth exemplified embodiment.
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Figure 1 shows an underground liquid management system 1 in accordance with
the present invention. The underground liquid management system 1 comprises a
first
store 2. This store 2 is formed by means of one or a plurality of cavities of
a mine M. In
accordance with the invention, a mine is understood to be all types of mines,
pits and the
like which comprise underground cavities, and all types of natural caverns or
cavern
systems.
Disposed above the first store 2 is at least one second store 3. This second
store 3
can be a store which is additionally provided independently of the cavities of
the mine;
i.e., e.g. a store provided in the area surrounding the mine (above the
(earth's) surface 0).
Preferably, the second store 3, along with the first store 2, are formed by
cavities of the
mine M. In this manner, it is possible to utilise already existing structures
of a mine M in
a simple and cost-effective manner for an underground liquid management
system.
However, the invention is not restricted to a specific number of stores and
can comprise
any number of stores; in particular depending on how many stores are provided
in the
mine M. However, in theory the number of stores can also be increased
artificially, in that
e.g. further shafts are provided or individual shafts are subdivided
artificially into a
plurality of sub-shafts. The number of stores can also be less than the stores
provided in
the mine M, in that stores which are not required are not integrated into the
system.
Whereas in Figure 1 the stores 2, 3 are disposed with their entire volume one
above
the other, it is also feasible for at least the bottom of the second store 3
to be disposed
above the first store 2. In this case, the stores 2, 3 are thus disposed in a
mutually offset
manner in a horizontal direction one after the other. The only decisive aspect
is that the
stores are disposed in such a manner that a gravitation-induced flow of liquid
can be
effected from a higher level of a store 3 to a lower level into another store
2.
In accordance with the invention, the term "liquid" can be understood to refer
to
any liquid. Preferably, the liquid is water, wherein in this case it can be
groundwater
and/or surface water and/or water guided artificially into the mine. In this
manner, a liquid
management system 1 or a water management system is provided, by means of
which
groundwater, surface water, industrial water or drinking water can be stored
and in
particular also cleaned. This is, in turn, an important basis for particularly
effective
groundwater protection and for the improved possibility of effecting
renaturation of the
entire system, its surrounding area and the liquids (e.g. surface water or
groundwater). It
is also feasible for the liquid to be (any) liquid, which is stored in the
mine after it has
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been shutdown, for the purposes of storage, cleaning, energy generation and/or
energy
storage. In the last-named case, the economic feasibility of an operation can
also be
maintained after closure of the mine M, in that the mine M is "converted" in a
cost-
effective and simple manner for the storage and provision of liquids, i.e.,
enjoys new and
further use, whereas the liquid management system 1 can be used at the same
time for
generating energy by means of the liquid stored therein. If numerous stores
are provided,
the liquid management system 1 can also be used for various liquids at the
same time,
wherein the liquids, in turn, can be used independently of each other for the
purposes of
storage, cleaning, energy generation and/or energy storage, as explained
hereinafter.
The underground liquid management system 1 also comprises a line 4, which
connects the stores 2, 3, for the purpose of conducting a liquid located in
the mine M. The
liquid management system is not restricted to a specific number of lines 4,
26. For
instance, individual stores can be connected to one or a plurality of lines 4.
Furthermore,
it is also possible for only individual stores, a plurality of stores or all
of the stores to be
interconnected (cf. Figure 2 to Figure 4). It is likewise feasible for
individual stores, a
plurality of stores or all of the stores to be connected to only one reservoir
4 (cf. Figure 4).
Alternatively or in addition, the line 26 can also extend out of the mine M,
i.e., to the
(earth's) surface 0 or beyond it to the outside environment of the mine M (cf.
Figure 2).
The lines 4, 26 are formed preferably as a rising pipe and can be formed
either by
means of a separately provided rising pipe 4, 26, which e.g. have already been
provided
during operation of the mine M, or by means of already existing or
subsequently
introduced connection shafts 5, 27 provided in the mine M. The lines 4, 26
extend
upwards from the respective store 2 into at least one or a plurality of or
even all of the
stores 3 disposed thereabove and/or outwardly, i.e. to above the (earth's)
surface 0. This
is described in greater detail in further exemplified embodiments. It should
be noted that
the invention is not restricted to the substantially vertical alignment of the
lines 4, 26
shown in the Figures, as long as the lines 4, 26 permit the conveyance of
liquid from a
lower level towards a higher level.
In order to prevent an undesired back-flow of the liquid from a higher level,
i.e.,
the second store 3 in Figure 1, to a lower level, i.e., to the first store 2
in Figure 1, via the
line 4, 26, a vacuum valve 6 is provided preferably at the upper end of the
line 4, 26 (or
rather in the shaft 5, if the shaft is used as a line).
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In order to guide the liquid through the line 4, a pumping device P is
provided in
the store 2, which is situated at a deeper location corresponding to the flow
direction, by
means of which pumping device the liquid is drawn in from the first store 2
and conveyed
into the second store 3 via the line 4. For this purpose, the pump P is
disposed preferably
5 on the bottom of the first, deeper store 2, in order to permit the most
effective possible
conveyance of all of the liquid from the first store 2.
In accordance with the invention, in order to operate the pump P there is
provided
a geothermal device 7 which is illustrated only schematically in the Figures.
Geothermal
devices are well known and therefore shall not be described further at this
juncture. The
10 provision of a geothermal device is particularly advantageous since
mines M extend
generally to significant depths and the generation of geothermal energy
(ground heat) is
simple by reason of the low, additional drilling depth in comparison with the
case where
the geothermal energy must be generated starting from the earth's surface 0.
Therefore, in
a simple manner and by means of regenerative energies, it is also possible to
ensure
operation of the pump P at all times in an environmentally sound manner and
independently of external influences. Furthermore, the generated energy
(electrical
energy, heat, cooling energy) can be provided for other components inside or
outside of
the system and/or can be fed into an electricity network or a heating or
cooling circuit or
network or the like.
The geothermal energy can be used in addition for a thermal power station/heat
pump which are not illustrated but are well known, wherein the heat energy can
be used
for the system itself or can be discharged from the system for external use.
It is thus
possible to use the generated thermal energy directly by discharging it in a
known manner,
and to use the thermal energy indirectly by converting it into electrical
energy.
In addition to the heat pump, the geothermal device 7 can also be provided as
an
energy system for production both of heat and also cooling energy. For
example, in the
case of direct heat exchanger-ground heat systems, cooling energy is produced
as a waste
product in heat generation. In order also to render it accessible and use it,
the installation
of the geothermal device 7 can involve two deep drilling procedures, in which
in each case
a probe circulates. By reason of the geothermal heat, a liquid cooling medium
evaporates
therein, absorbs energy and travels by means of inherent pressure to a
compressor.
Consequently, as the heat is extracted the probe cools down. The cooling
energy
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11
generated can then be used by a second circuit within the probe, wherein the
cooling
medium used is e.g. an ammonia mixture.
The heat and cooling energy generated or produced by the geothermal device 7
as
a heat pump or energy system can be used, just like the generated electrical
energy, for the
(surrounding) industry, residential areas and the like or the mine M itself
The geothermal
device 7 or the ground heat generated (upon conversion of the mine) can thus
likewise be
used as an energy supplier for electricity, heat and cooling energy, e.g. for
sale to third
parties or for the auxiliary power (e.g. of the active mine).
In addition to the geothermal device 7 as the primary energy source, it is
also
feasible for the system 1 to comprise further energy sources. In particular,
all current and
future regenerative energy sources can be used. These include in particular
wind energy
plants (not shown) for generating wind energy, solar energy plants (not shown)
for
generating solar energy, pump storage stations for generating flow energy or
other known
energy sources.
In particular, the pump storage station is particularly advantageous, as it
can be
integrated in space-saving and cost-saving manner in the underground liquid
management
system 1. For this purpose, already existing, vertical connection shafts 5 or
other passages
are preferably used between the stores 2, 3 which are preferably disposed one
above the
other. For this purpose, e.g. a turbine 8 or another comparable electricity
generating
device is provided therein for the purpose of generating electricity. By
virtue of the fact
that the liquid flows off from the second, higher store 3 into the first,
deeper store 2 by
reason of gravitational forces, the turbine 8 is driven and produces
electricity. For this
purpose, e.g. a generator 9 is also provided. The electricity can then be
provided e.g. for
the mine M or can be fed into an electricity network.
In order to regulate the flow rate of the liquid from the second store 3 to
the first
store 2, a closure device, e.g. a stop valve 10, is provided preferably in the
flow path
between the second store 3 and the water turbine 8. This stop valve 10 can be
used
preferably to regulate the flow rate of the liquid in a continuously variable
manner. In the
closed state, the second store 3 in a storage operation can thus be used as a
store for
providing the liquid which is conveyed by means of the pumping device P
(driven at least
by geothermal energy) from a lower level into the upper store 3. The stored
liquid in the
second store 3 can then be removed from the second store 3 e.g. for further
use.
Alternatively, the stored liquid can be used as required by optionally opening
the stop
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valve 10 for the purpose of producing energy (electricity), in that the
turbine 8 is driven as
the liquid flows from the second store 3 to the first store 2.
It is also feasible for an additional store, not illustrated in the Figures,
to be
provided which is formed either likewise by cavities of the mine M or else is
disposed in
addition, e.g. above the (earth's) surface 0. A store which is disposed in
this manner can
be formed as a liquid supply or liquid reservoir, in which liquid is collected
and provided.
This liquid supply can be provided for the operation of the mine M itself or
even for any
other purposes, e.g. for removal or else as a liquid reservoir or water
reservoir for the
surrounding population or agriculture or for renaturation purposes. The liquid
reservoir
can also be formed by one of the already previously described stores,
preferably the store
3 located closest to the (earth's) surface 0, in that in a particularly
preferable manner the
discharge to the further stores 2 is blocked or retarded (e.g. by means of the
stop valve 10).
As already described, the cavities of the mine M which form the stores can
extend
over various groundwater reservoirs. It is conceivable that some stores extend
in
uncontaminated layers N and other stores extend in contaminated layers K.
Contaminated
layers K are located mostly at greater depths, in which extraction is operated
in the mine
M. Either the material extracted/to be extracted or a material used for
extraction purposes
in the mine M can cause e.g. the groundwater to become polluted, which leads
to
contamination of the groundwater and thus of the corresponding geological
layer. This is
illustrated by way of example in Figure 2 which shows an underground liquid
management system 20 in accordance with a second exemplified embodiment. In
relation
to the first exemplified embodiment, like features are designated by like
reference
numerals. In relation to all corresponding features, reference is made in full
to the above
statements relating to the first exemplified embodiment. It should also be
noted that any
combination of the features and embodiments of the exemplified embodiments
together is
possible within the scope of the invention.
Figure 2 shows a mine M having four stores 21, 22, 23, 24 which are each
disposed one above the other in a vertical direction. However, the invention
is not
restricted to a specific number of stores or their illustrated arrangement
with respect to
each other. On the contrary, any number of stores is feasible, wherein at
least one store
(or the bottom thereof) must be disposed above at least one other store (of
the bottom
thereof).
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In accordance with the second exemplified embodiment, the two lower stores 21,
22 are disposed in a contaminated layer K.
The two upper stores are located in an uncontaminated layer N. However, it is
also
feasible e.g. for the uncontaminated layers N and contaminated layers K to be
disposed
differently or else also for one or a plurality of shafts or stores to extend
over at least one
or a plurality of geological layers, wherein at least one of the layers may be
contaminated
and at least one other one may be uncontaminated. The latter case will be
explained in
greater detail with reference to Figure 3.
A separation between an uncontaminated layer N and a contaminated layer K,
which extend mostly in water-carrying, natural layers (groundwater reservoirs
or aquifers),
is generally achieved in a natural manner by so-called aquifuges, i.e., water-
impermeable
layers, such as e.g. clays. In Figure 2, an aquifuge A is illustrated by way
of example and
schematically by means of a broken line.
In accordance with the second exemplified embodiment, the two lower stores 21,
22 are connected to a line 4. Likewise, the two upper stores 23, 24 and the
lowermost and
uppermost stores 21, 24 are connected by means of lines 4. The uppermost store
24 is also
connected by means of a further line 26 to the surface 0 or the outside
environment.
However, the invention is not restricted to this type of arrangement of the
lines 4, 26. On
the contrary, each store can be connected in any manner to each other store or
the surface
0 by one or a plurality of lines 4, 26 which are/were already provided
preferably by the
mine operation.
The lines 4, 26, as also described in the first exemplified embodiment, are
preferably each provided with a pumping device P for conducting a liquid;
where
expedient, a plurality of lines 4 can also be provided with a pump P. The
pumping devices
P are driven at least by means of geothermal energy by a geothermal device 7,
optionally
also in addition by means of other, preferably regenerative energy sources.
Provided between the stores 21, 22, 23, 24 are respective connection shafts 5
which preferably were also already provided when the mine M was opened. In at
least
one, a plurality of or all (see Figure 2) of the shafts 5 it is possible to
provide a stop valve
10 and a turbine 8 - connected downstream in a fluidic manner - with a
generator 9, by
means of which energy can be generated.
In order to prevent uncontrolled mixing of the liquid, which is located in the
stores
23, 24 in the uncontaminated layer N, with the liquid located in the stores
21, 22 in the
CA 02825072 2013-07-18
14
contaminated layer K, and therefore to avoid greater damage to the groundwater
and thus
to the surrounding ecosystem, a filter device 25 is preferably also provided
as a cleaning
stage. As shown in Figure 2, the filter device 25 is connected in a fluidic
manner to the
pumping device P. Preferably, the filter device 25 is disposed in at least
one, a plurality of
or all of the lines 4, 26, which connect the stores 21, 22, 23, 24, preferably
downstream of
the pumping device P such that as the liquid is conducted through the lines 4,
26 it is
guided through the filter device 25 and is thus cleaned. It is also feasible
that as an
alternative or in addition to the pump storage station (i.e., stop valve 10,
turbine 8,
generator 9) the filter device 25 is disposed in a shaft (passage) 5, so that
cleaning of the
liquid takes place as it is drained or conducted from an upper store to a
lower store, e.g.
thus in the energy generating operation.
It is thus possible to separate the lower stores 21, 22 from the upper stores
23, 24
selectively in terms of systems engineering by closing the stop valve 10
between the
particular stores 22, 23 which are disposed in the transition from the
uncontaminated layer
N and the contaminated layer K. In this manner, the groundwater in
uncontaminated
layers N is protected against unnecessary contamination, whereas at the same
time the
contamination in the contaminated layer can be reduced, in order thus to
restore the area
surrounding the mine to its natural original state, i.e., renaturation.
In the lower stores 21, 22 a closed cleaning circuit can then be provided, in
order to
clean the contaminated liquid located therein. As previously described, for
this purpose
the liquid is guided via the pump P and the line 4 from the lowermost store 21
into the
store 22 located thereabove. In the course of this pumping or storing process,
the liquid is
cleaned by means of the filter device disposed in the line 4. The liquid
guided into the
store 22 and optionally stored can flow off into the lower store 21 in an
energy generating
operation by opening the stop valve 10 disposed between the two lower stores
21, 22. The
turbine 8 disposed in the flow path of the liquid is influenced by the liquid
of the upper
store 22 flowing off. Pollutants, e.g. in the groundwater of the contaminated
layer K, can
thus be reduced or removed optionally in the course of a plurality of cleaning
cycles, while
at the same time energy can be generated and the cleaned liquid can then be
provided. It is
thus possible, by reducing the contamination of the groundwater entering into
or located in
the stores (e.g. over a plurality of cleaning cycles) to clean the groundwater
located in the
corresponding aquifer and therefore to convert the layer into a substantially
uncontaminated layer.
CA 02825072 2013-07-18
In essence, a common aspect of all of the exemplified embodiments is that the
stores can have a ventilation device, in order to equalise an air volume in a
store by out-
flowing or in-flowing liquid. This ventilation device can be a ventilation
line (not
illustrated) connected to the surrounding area above the (earth's) surface 0
and used for
5 aeration and deaeration of the respective stores.
Until the liquid in the lower stores 21, 22 or the groundwater in the
contaminated
layer K has been cleaned, a closed circuit can likewise be provided in the two
upper stores
23, 24 in the manner already described for the purpose of generating energy
and storing
liquid. The liquid can optionally also be cleaned in the upper stores 23, 24
with a filter
10 device 25.
When the liquid in the lower cleaning circuit has been sufficiently cleaned,
it can
be conveyed via a further line 4, which is provided with a pump P, into one or
a plurality
of stores 22, 23, 24 disposed thereabove, where it is provided either as a
pump store for
generating energy or is kept available in one of the upper stores or a further
store, not
15 illustrated.
In some regions, in which the liquid management system in accordance with the
invention is used, the groundwater surrounding and optionally entering into
the mine M
has a very low pH value of only ca. 2 to 3. It is thus also feasible that at a
corresponding
location, preferably in or between the stores 21, 22, 23, 24, the cleaning
stage also has a
cleaning device (not illustrated), by means of which the pH value of the
liquid can be
changed; depending on which pH value between 0 and 14 the liquid has and which
desired
pH value the liquid is to have, the pH value of the liquid can thus optionally
be raised or
lowered. The cleaning device can be constructed in such a manner that the
liquid is
guided in a purposeful manner through or along natural or artificially
provided chalk
layers or chalk-coated devices. As the liquid is conducted or guided past, the
chalk (or
another substance provided in the cleaning device) dissolves slowly into the
liquid and
leads to an increase/decrease in the pH value and preferably to neutralisation
of the
conducted liquid (e.g. the groundwater). The cleaning device can be formed
e.g. in or
with a previously described filter device 25. For example, the cleaning device
can also be
provided in a chalk-containing store (e.g. one of the stores 21, 22, 23, 24 in
Figure 2),
wherein e.g. the walls of this store are provided in a natural or artificial
manner with a
chalk layer. The cleaning device can be provided in or between each arbitrary
store and in
each layer (contaminated; uncontaminated).
CA 02825072 2013-07-18
16
In a further development of the previously described cleaning device, it can
additionally be equipped with a pH value sensor which measures the pH value in
one or all
of the stores. On the basis of the obtained measurement results and of the pH
value to be
adjusted, the liquid can then optionally be guided through the cleaning
device, so that the
pH value can be adjusted according to the individual requirements. It is
feasible for the
cleaning device to have a first part for raising the pH value and a second
part for lowering
the pH value. The liquid whose pH value is to be changed can then optionally
not be
guided at all or can be guided through the first or second part of the
cleaning device,
depending upon whether the pH value of the liquid is to be maintained, raised
or lowered.
Provided in the uppermost store 24 is the line 26 which extends towards the
surrounding area and extends preferably to above the (earth's) surface 0. The
line 26 has
a pumping device P which is disposed optionally in the store 24 or outside the
mine M,
e.g. on the (earth's) surface 0. For example, the line 26 can also be provided
or optionally
introduced through the shaft 27 which connects the uppermost store 24 to the
surrounding
area. This line 26 then serves, optionally in conjunction with the pumping
device P and
further connections, to channel the liquid from the store 24, which serves as
a storage
reservoir, as an output system S. The combination of liquid management system
20 and
output system S thus forms a waterworks W. The liquid is then preferably
water, such as
e.g. groundwater or surface water or water guided artificially into the mine
M. The liquid
management system 20 can then be defined as a water management system. This
type of
waterworks W serves to provide drinking water or industrial water which can be
channelled upon requirement from the liquid management system 20. Equally, the
waterworks W effects renaturation of the surrounding area of the mine and of
the liquid
and also provides improved groundwater protection.
It should be noted that along with the uppermost store 24, in addition or
alternatively each arbitrary store 21, 22, 23 can have a line 26 which extends
to above the
(earth's) surface 0 to the outside environment. Furthermore, the line 26 can
also be
provided with a filter device 25. Equally, the end of the line 26 protruding
out of the mine
M can be provided with a vacuum valve 6 or a connection for connecting a
suction device
or a collecting device or the like, in order to reliably capture liquid which
has been output.
The line 26 can also issue into a liquid reservoir, not illustrated.
Figure 3 shows a third embodiment of an underground liquid management system
30. In relation to the aforementioned exemplified embodiments, like features
are
CA 02825072 2013-07-18
17
designated by like reference numerals. In relation to all corresponding
features, reference
is made in full to the above statements. It should also be noted that any
combination of
the features and embodiments of the exemplified embodiments together is
possible within
the scope of the invention.
In accordance with Figure 3, the underground liquid management system 30
comprises three stores 31, 32, 33 formed from cavities of a mine M. This
exemplified
embodiment describes a case, in which (at least) one store 32 extends such
that it
protrudes from an uncontaminated layer N into a contaminated layer K; i.e., at
least one
store extends through a plurality of geological layers, wherein at least one
of these layers
is a contaminated layer.
In such a case, it is possible for all of the stores 31, 32 located in a
contaminated
layer K to be separated in a fluidic manner from stores 33 in uncontaminated
layers N e.g.
by closure of the uppermost stop valve 10 in the shaft 5. This produces a
closed cleaning
circuit for cleaning the liquid in these stores 31, 32, as has already been
described
previously. If the liquid is cleaned, it can be connected in any previously
described
manner to stores 33 in uncontaminated layers for energy generation, storage
and optionally
further cleaning of the liquid. The closed uppermost stop valve 10 can then
optionally be
opened.
However, in this case liquid from uncontaminated layers N if anything becomes
mixed unnecessarily with contaminated liquid and is thus polluted. In
accordance with the
third exemplified embodiment, it is thus feasible to avoid uncontrolled mixing
of the
liquids by means of suitable structural separating measures and thus to
provide effective
groundwater protection. This is preferably achieved by providing an artificial
barrier 35 in
the store 32 extending over uncontaminated layers N and contaminated layers K,
which
barrier separates this store into a lower region 321 and an upper region 322.
The barrier
is preferably disposed such that it extends along the aquifuge A which
separates the
contaminated layer K from the uncontaminated layer N. The barrier 35 consists
preferably
of a material which is at least impermeable to liquids. The barrier 35 is
(sealingly)
disposed in the store 32 such that no liquid can pass from the upper region
322 of the store
30 32, which is disposed in an uncontaminated layer N, to the lower region
321 of the store
32 which is disposed in a contaminated layer K (and vice versa). Therefore,
the
combination of the barrier 35 and the aquifuge A prevents any mixing of
uncontaminated
liquid and contaminated liquid in a more effective manner.
CA 02825072 2013-07-18
18
Furthermore, a passage 36 for optionally connecting the two regions 321, 322
of
the store 32 can be provided in the barrier 35. The passage can optionally be
closed
preferably by a closure device, such as e.g. a stop valve 10. Furthermore, a
turbine 8 -
connected in a fluidic manner downstream of the stop valve 10 - with a
generator 9 can be
provided in the passage 36.
In order to avoid unnecessary contamination of the liquid in the upper stores
or
storage regions 33, 322, the stop valve 10 in the barrier 35 is closed during
a cleaning
process in the lower two stores or storage regions 31, 321 until the pollution
in the liquid
has been adequately removed.
As can be seen in Figure 3, stores each located one above the other are
connected
by means of lines 4 and pumping devices P connected thereto. In the same
manner, the
two storage regions 321, 322 of the central store 32 are also connected
together, wherein
the line 37 connecting them in a fluidic manner extends preferably in a
sealing manner
through the barrier 35. Furthermore, a filter device 25 can be provided in the
lines 4, 37 or
even in another way (e.g. in the shafts 5 or the passage 36). At a desired
location, a
cleaning device, not illustrated, can likewise be provided for the purpose of
changing the
pH value of the liquid.
The pumping devices P are coupled to a geothermal device 7 in the manner
described above.
As can also be seen in Figure 3, the lowermost store 31 is connected to the
overlying store 32 (specifically its lower region 321) by means of a line 4.
It is also
possible for at least the lowermost store 31 to be connected directly to the
uppermost store
33 or a plurality of overlying stores or storage regions. To avoid unnecessary
costs (e.g.
for an additional pumping device), it is feasible for individual lines 4 to be
connected
together by connection line portions 41. For this purpose, Figure 3 shows by
way of
example that a line, which connects the lowermost store 31 to the lower region
321 of the
central store 32, is connected by a connection line portion 4' to a line 4
which connects the
upper region 322 of the central store to the uppermost store 33. Preferably,
valves 38 are
provided in each case in the connection points of the lines 4, 4'. These
valves 38 can be
used optionally to regulate the liquid flow and optionally to determine the
flow direction
so as to avoid mixing of contaminated and uncontaminated liquid. Such
connection line
portions 4' can be provided arbitrarily between all of the lines 4, 26, 37.
CA 02825072 2013-07-18
19
Figure 4 shows a fourth embodiment of an underground liquid management system
40. In relation to the aforementioned exemplified embodiments, like features
are
designated by like reference numerals. In relation to all corresponding
features, reference
is made in full to the above statements. It should also be noted that any
combination of
the features and embodiments of the exemplified embodiments together is
possible within
the scope of the invention.
The underground liquid management system 40 in accordance with Figure 4
corresponds substantially to that of Figure 2. In Figure 4, a store 41 is
disposed in the
contaminated layer, whereas the two overlying stores 42, 43 are provided in an
uncontaminated layer.
The essential difference in the underground liquid management system 40 of the
fourth embodiment resides in the configuration of the cleaning stage. In
addition or as an
alternative to the above-described filter devices 25 and cleaning devices
which for the sake
of simplicity are not illustrated in Figure 4, the store can be filled at
least partially with a
porous material which then forms the filter device 44 for reducing
contaminants in the
liquid (e.g. surface water or groundwater) or the contaminated layer per se
(e.g. over the
liquid). This type of filter device is also described in a comparable manner
in EP 2 058
441 Al. This will be illustrated by way of example hereinafter.
In Figure 4, the store 41 located in the contaminated layer K is filled at
least
partially with a porous material 45. Within the scope of the present
invention, the phrase
"at least partially" is to be understood to mean that the store 41 is to be
filled with at least
as much porous material 45 as is required in order to store and clean the
liquid in a
sufficiently effective manner.
Preferably, the porous material 45 is rubble, gravel, sand (e.g. quartz sand)
or a
mixture thereof However, loam, silt and/or clay can also be used. Geotextiles
can also be
used. Other materials, such as e.g. synthetic materials, can also be used if,
by reason of
their porosity, the ratio of the volume of all of their cavities to their
outer volume, they are
able to store and transport water.
The filter device 44 comprises at least one barrier layer 46 or a plurality of
barrier
layers 46 (Figure 4) which is/are disposed inside the store 41. The barrier
layer 46 is also
provided with at least one passage 47 for liquids.
Apart from the passage 47 which is permeable to water, the barrier layer 46 is
produced from a material which is substantially impermeable to water. Within
the scope
CA 02825072 2013-07-18
of the present invention, the phrase "substantially impermeable to water" is
understood to
mean that the barrier layer 46 is formed in such a manner that the main part
of the water
which seeps through the store 41 is prevented from passing through the barrier
layer 46
into the region above or below the barrier layer 46.
5 The barrier layer 46 serves to lengthen the seepage path (see arrows in
Figure 4) of
the liquid to be cleaned through the porous material 45 of the store 41. By
lengthening the
seepage path, the liquid can be stored for longer periods inside the store 41.
Moreover, the
liquid is filtered over a longer period of time, which leads to an improved
reduction in
contamination and as a result of which the quality of the cleaned liquid is
thus improved.
10 If the liquid reaches the barrier layer 46, then it begins to accumulate
by reason of
liquid seeping through subsequently. In this accumulated state, it enters into
the
capillaries of the porous material 46. As a result, in the region immediately
upstream of
the barrier layer 46, particles of muck and dirt become deposited or settle in
a particularly
effective manner in and on the pores.
15 Preferably, the barrier layer 46 is disposed horizontally, since when
the barrier
layer is disposed horizontally the seepage path of the liquid through the
filter device 44 is
at its longest, which has a particularly positive effect upon the quality of
the filtrated
water. However, any other inclination of the barrier layer 46 is possible if
the
characteristic of the barrier layer 46, namely to lengthen the seepage path of
the liquid, is
20 not lost as a result. The individual barrier layers 46 within a system
can each have the
same degree of inclination but can also be different in terms of their degree
of inclination
with respect to each other.
The passage 47 only takes up only a small amount of surface area relative to
the
entire barrier layer 46. Preferably, this constitutes a surface area of 5 to
20% in relation to
the entire surface of the barrier layer 46.
Preferably, the passage 47 is disposed in the outer region of the barrier
layer 46, so
that the path travelled by the liquid along the barrier layer 46 corresponds
approximately
to the maximum possible, which produces a particularly good filtration result.
In the case of at least two barrier layers 46, as shown in Figure 4, the
passages 47
of each case two adjacent barrier layers 46 are preferably offset with respect
to each other,
particularly preferably they are disposed oppositely with respect to each
other, so that the
seepage path of the liquid is maximised.
CA 02825072 2013-07-18
21
Furthermore, the filter device comprises a collecting vessel 48 which extends
from
the bottom of the store 41 in a substantially vertical direction upwards,
preferably to the
top or just before the top of the store 41. It is also feasible for the
collecting vessel to
extend in the form of a well to the (earth's) surface 0.
The collecting vessel 48 has, at least below the lowermost barrier layer 46,
at least
one opening 49, through which the cleaned liquid can flow or seep. The cleaned
liquid
can then be stored and provided in the collecting vessel 48; either for
removal, for further
cleaning and/or for generating energy.
There are different possible ways of removing the liquid from the collecting
vessel
48, and the two preferred ways are described hereinafter.
In accordance with a first possible way, the filter device 44 preferably has a
pumping device P inside the collecting vessel. The pumping device is
preferably disposed
at the bottom of the store 41. From this pumping device P, a line 4 extends
upwards
through the collecting vessel 48 and issues in an outlet 50, so that the
upwardly conveyed
liquid can be introduced into the store 41 or the filter device 44 for renewed
cleaning
above the uppermost barrier layer 46.
As illustrated in Figure 4, it is also feasible for the line 4, which extends
from the
collecting vessel 48, to extend through all of the stores 41, 42, 43 and
optionally to above
the (earth's) surface, in order also to provide the liquid, preferable after
cleaning has been
effected, in the stores 42, 43 disposed thereabove or the surrounding area. At
locations in
the stores 41, 42, 43 required for this purpose, the line 4 comprises valves
38, from which
output line portions 4" branch off By means of these valves 38, the liquid
flow can be
optionally regulated and the flow direction can be optionally determined so as
to avoid
mixing of contaminated and uncontaminated liquid. If the cleaning is
completed, the
valve 38 in the store 41 can be closed with respect to the corresponding
output line portion
4", so that the liquid is then guided by the line 4, which is open at the top,
optionally into
the stores 42, 43, which are connected by means of this line 4, or into the
surrounding
area.
It should be noted that all of the previously described lines 4 can be formed
according to the line 4 which is illustrated in Figure 4 and extends over all
of the stores
and optionally to the (earth's) surface 0 and is provided with corresponding
valves 38 and
output line portions 4". In this simple manner, the number of lines 4, 26, 37
can be
reduced, as only a small number of lines 4 has to be provided in order to
connect a
CA 02825072 2013-07-18
22
plurality of stores. It is also feasible that, above and beyond the
exemplified embodiment
illustrated in Figure 4, a pump is provided in the line 4, which extends over
all of the
stores 41, 42, 43, within each store 41, 42, 43, so that only a single line 4
is required for
operating a liquid management system 1, 20, 30, 40.
In accordance with a second possible way of removing the liquid from the
collecting vessel 48, the collecting vessel 48 can be disposed in such a
manner that it is
disposed above a connection, e.g. a shaft 5 which leads to an underlying store
(not
illustrated), wherein the collecting vessel 48 preferably (substantially
completely)
surrounds the shaft 5. As already previously described, by means of a stop
valve 10 the
shaft 5 can be closed and optionally can be opened e.g. when the collecting
vessel 48 is
filled. The liquid can then be guided via the stop valve 10 and the shaft 5
into the store
disposed therebelow. Preferably, an already previously described turbine 8
with a
generator 9 is likewise disposed accordingly in the shaft 5.
The store which is disposed below the store 41 can likewise be equipped with a
filter device 44, as illustrated in the lowermost store 41 of Figure 4, so
that the cleaning
performance is improved.
Within the scope of the invention, in the case of liquids polluted with
radioactive
substances it is particularly advantageous if the stores (2, 3, 21, 22, 23,
24, 31, 32, 33, 41,
42, 43) or mines (M) are provided in clay rocks, as found e.g. in the Opalinus
clay
formation in the Jura region. This is particularly advantageous in particular
in the case of
uranium-contaminated mines. The clay minerals (e.g. kaolinite) contained in
the clay
serve to bond the radioactive substances which can thus be cleaned out of the
liquid. In
combination with the iron minerals which are contained in the clay rock and
serve to
reduce the radioactive substances and thus release them in the clay rock, the
cleaning of
liquids can be further improved in the underground liquid management system
(1, 20, 30,
40).
It is additionally or alternatively possible for the walls of the stores (2,
3, 21, 22,
23, 24, 31, 32, 33, 41, 42, 43) or mines (M) to be provided with natural clay
(in particular
containing clay minerals) for the purpose of cleaning the liquid. For this
purpose, a clay
layer can be applied to the inner walls of the stores (2, 3, 21, 22, 23, 24,
31, 32, 33, 41, 42,
43), in particular if the mine (M) is not provided in clay rock. If the clay
layer has
adequately bonded radioactive substances or if it is saturated with
radioactive substances,
it can be removed and disposed of in an environmentally responsible manner, or
stored or
CA 02825072 2013-07-18
23
processed. If the mine (M) is provided in clay rock, e.g. the outermost clay
layer of the
inner walls of the stores (2, 3, 21, 22, 23, 24, 31, 32, 33, 41, 42, 43) can
be removed at
regular intervals and disposed of or processed accordingly, in order to remove
the heavily
contaminated clays layers and to continue cleaning with a "fresh" clay layer.
It is also feasible, by means of the use of clay to provide absorbing
separating
walls or separating layers (consisting of clay or clay rock) in the
underground liquid
management system (1, 20, 30, 40). For this purpose, the separating walls or
separating
layers formed from clay (rock) are provided preferably at locations in the
mine (M) in or
between the stores (2, 3, 21, 22, 23, 24, 31, 32, 33, 41, 42, 43) or even
separately, e.g. thus
outside the mine (M) where (contaminated) liquid is present or flows through;
in a natural
or artificial manner.
In relation to the exemplified embodiments, this means that separating walls
or
separating layers consisting of clay can be provided e.g. in the connection
shafts 5, 27, the
filter devices 25, the lines 4, 26, 37, the barrier 35, the passage 36 or at
other suitable
locations of the mine (M). For example, the barrier 35 or the filter device 25
can also be
formed per se from a corresponding clay. It is likewise feasible to provide
additional
barrier layers consisting of clay as separating walls and a cleaning device,
in particular for
liquids polluted with radioactive substances.
It is also feasible to provide clay as a filter element, e.g. as loose clay
particles, in
the mine (M), so that it comes into contact with the contaminated liquid and
can bond the
radioactive substances contained therein. In other words, the clay does not
have to be
present as a layer or wall, but rather can be provided in any form, e.g.
"fixed" (as clay
slabs or clay chunks), "fixedly disposed" (as a separating layer or separating
wall),
"loosely disposed" (as filter particles in a (defined) filter housing) or
"arbitrarily loose"
(e.g. elutriated in the contaminated liquid). Preferably, the clay or clay
rock is provided in
such a manner that it can optionally be replaced or removed if a predetermined
amount of
contaminated (radioactive) substances is bonded therein. In this manner, an
effective
cleaning device is provided for liquids which are contaminated in particular
with
radioactive substances.
A method for operating a liquid management system 1, 20, 30, 40 will be
described hereinafter.
The invention also includes a method for operating a liquid management system
1,
20, 30, 40 for mines M, comprising the step of pumping a liquid from at least
one first
CA 02825072 2013-07-18
24
store 2,21, 22, 23, 31, 32, 41, 42, which is formed by a cavity of the mine M,
into at least
one second store 3, 22, 23, 24, 32, 33, 42, 43, the bottom of which is
disposed above that
of the first store 2, 21, 22, 23, 31, 32, 41, 42, via at least one line 4,
which connects the
stores 2, 3, 21, 22, 23, 24, 31, 32, 33, 41, 42, 43, for conducting the
liquid, wherein the
liquid is conveyed by means of at least one pumping device P through the lines
4 from the
first store 2, 21, 22, 23, 31, 32, 41, 42 into the second store 3, 22, 23, 24,
32, 33, 42,43,
and wherein the pumping device P is driven by means of a geothermal device 7
of the
liquid management system 1, 20, 30, 40.
The method also comprises the step of cleaning the liquid by means of a filter
device 25, 44 of a cleaning stage, wherein either the filter device 25 is
connected in a
fluidic manner to the pumping device P or is disposed in a fluidic manner in a
passage 5,
which connects the stores 2, 3, 21, 22, 23, 24, 31, 32, 33, 41, 42, 43 such
that the liquid is
cleaned during the pumping process or as it is conducted through the passage
5, or
wherein the filter device 44 is formed from a porous material 45 which fills
the store 41 at
least partially, and the liquid is cleaned as it is conducted through the
porous material 45.
Furthermore, a passage 5 can be provided between the first store 2, 21, 22,
23, 31,
32, 41, 42 and the second store 3, 22, 23, 24, 32, 33, 42, 43, wherein the
method in
accordance with the invention can also comprise the steps of draining the
liquid from the
second store 3, 22, 23, 24, 32, 33, 42, 43 into the first store 2, 21, 22, 23,
31, 32, 41, 42 by
optionally opening a stop valve 10 provided in the passage 5, and generating
energy by
driving an energy generating device 8 by means of the liquid drained via the
passage 5,
wherein the energy generating device 8 is disposed in the passage 5 downstream
of the
stop valve 10.
The invention is not restricted to the previously described exemplified
embodiments. On the contrary, the features described therein can be combined
in any
manner.
The invention is also not restricted to a number of stores and also not to the
number and type of configuration of the connection between the stores. For
example, two
or a plurality of stores can each be connected to one another by means of
shafts and/or
lines and corresponding pumping devices, turbines and stop valves. The stores
also do not
have to be disposed directly one above the other but rather can also be
mutually offset in
the horizontal direction and/or overlapping in the vertical direction, as long
as a previously
described fluidic connection is possible between at least some of the stores.
Furthermore,
CA 02825072 2013-07-18
any type and any number of cleaning stages (filter device; cleaning device)
can be
provided in each arbitrary store. Likewise, in addition to the geothermal
energy any
arbitrary energy source can be provided for operation of the system. Moreover,
the
geothermal energy can always be used both indirectly (electricity generation;
cooling
5 energy generation) and directly (heat generation).
