NL2039806B1

NL2039806B1 - Aquathermal assembly and aquathermal system

Info

Publication number: NL2039806B1
Application number: NL2039806A
Authority: NL
Inventors: Aat Biemond Johannes
Original assignee: Sparrows Holding B V
Priority date: 2023-08-22
Filing date: 2023-08-22
Publication date: 2025-12-18
Also published as: NL2039806A; NL2035653B1; NL2038482A

Abstract

The invention relates to an aquathermal intake filter unit for an aquathermal system, the filter unit comprising: - a filter screen that surrounds an inner space, wherein the inner space has a length and a width; - a water outlet that is operatively connected to the inner space and that is configured to discharge filtered water from the aquathermal intake filter unit; - at least one cleaning nozzle that is positioned in the inner space and that is directed towards the filter screen to supply cleaning liquid to the filter screen; wherein a distance between the at least one nozzle, preferably an outlet thereof, and the filter screen is in the range of 1% to 30% of the filter width. The invention further relates to an aquathermal filter assembly, an aquathermal system and a method for exchanging heat with a body of water.

Description

AQUATHERMAL ASSEMBLY AND AQUATHERMAL SYSTEM

The invention relates to an aquathermal assembly, an aquathermal system and a method for exchanging heat with a body of water, such as surface water or waste water.

In order to reduce carbon dioxide emissions, i.e. decrease the so-called carbon footprint, an increasing effort is made to develop sustainable energy systems that can provide heat and electricity to end-users, such as consumers and industries.

It has been found particularly challenging to provide (large amounts of) sustainable heat. One of the options for providing sustainable heat is the use of aquathermy. Aquathermy is the generation or extraction of usable heat from bodies of water, in particular surface water, such as lakes, rivers and other streams. Such aguathermy installations or assemblies generally are relatively large and have a significant internal energy use, thus reducing the efficiency of the installation.

The present invention is aimed at obviating or at least reducing the aforementioned problems. To that end, the invention provides an aquathermal filter assembly, comprising: - an inlet channel that is operatively connected 10 a first side of at least one filter unit; - an outlet channel that is operatively connected to a second side of the at least one filter unit; - a backwash channel that is operatively connected to the second side of the at least one filter unit and that comprises a backwash pump; - a backwash discharge channel that is operatively connected to the first side of the at least one filter unit; - atleast one filter valve that is positioned on the first side of the at least one filter unit; - atl least one backwash valve that is positioned on the second side of the at least one filter unit; wherein the filter unit has a filtering mode, in which the associated filter and backwash valves are in a first position such that the inlet and the outlet are fluidly connected to each other, and a backwash mode in which the associated filter and backwash valves are in a second position such that the backwash channel and the backwash discharge channel are fluidly connected to each other,

An advantage of the aquathermal filter assembly according to the invention is that, due to the application of a separate backwash channel and backwash pump, a separation of the pressure between the filtering and the backwashing can be applied. As a result, the pressure required for backwashing can be varied from the pressure required for filtering leading to a more efficient assembly. In particular, the (total) energy required to perform the filtering and backwashing steps is significantly lower, therewith increasing the energetic and hydraulic efficiency.

This is especially true if a plurality of filter units is applied in the assembly. According to the invention, the filtering pressure on a first filter unit {which is in the filtering mode) can differ from the backwash pressure applied to a second filter unit that at that time is in the backwash mode.

As a result, a filtering pump with a lower maximum power can be used to apply pressure for filtering. This leads to a higher hydraulic efficiency. Another advantage is that a freedom of design is achieved by the configuration according to the invention.

Another advantage of the aquathermal filter assembly according to the invention is that it, due to the separation of the filtering and backwash channels, provides a compact and integrated assembly. This is especially due to the larger freedom in design that is obtained by the separation of the filtering and backwash channels.

It is noted that, although the aguathermal filter assembly according to the invention may be used in combination with the aguathermal intake filler and is described here as such, the aquathermal filter assembly also constitutes a separate invention in itself and is herewith also described as such.

In an embodiment of the aquathermal filter assembly according io the invention, the assembly may comprise a filter flow circuit comprising the inlet channel, the at least one filter unit and the outlet channel and a backwash flow circuit comprising the backwash channel, the atleast one filter unit and the backwash discharge channel.

An advantage of two separate flow circuits is that each circuit can be operated at optimal conditions. For example, the backwash circuit may be operated at a (much) higher pressure than the filter circuit. In particular, the pressure in the backwash circuit may for example be in the range of 2.5 to 5.0 bar, and preferably be in the range of 3.0 to 4.0 bar to achieve efficient and good backwashing. The pressure in the filter circuit may for example be in the range of 1.0 to 2.5 bar, and preferably is between 1.0 and 1.5 bar to establish a good filtering performance. As a result, the (total) energy required to perform the filtering and backwashing steps is significantly lower, therewith increasing the energetic and hydraulic efficiency.

In an embodiment of the aquathermal filter assembly according to the invention, the filter valve and the backwash valves may be three-way valves, wherein the inlet channel and the backwash discharge channel may be connected to the three-way filter valve, and wherein the outlet channel and the backwash channel may be connected to the three-way backwash valve.

An advantage of using three way valves is that a compact and efficient assembly is achieved. This is mainly the result of obviating several valves and pipe/conduit sections that would otherwise be required.

A further advantage is that the control over the assembly is simplified, because the number of valves to be controlled is reduced.

In an embodiment of the aquathermal filter assembly according io the invention, the filter unit is configured for filtering the fluid to be filtered.

In an embodiment of the aguathermal filter assembly according to the invention a backwash channel inlet may be positioned in the outlet channel.

Although the backwash channel may be fed with a separate source, it is preferred that the backwash channel is fed from the outlet channel. An advantage thereof is that the backwash fluid is a filtered (and thus clean) fluid. Another advantage is that it provides a more compact and efficient assembly. A further advantage is that, due to the backwash pump, the fluid from the outlet channel can be provided at the required backwash pressure regardless of the pressure in the outlet channel.

In an embodiment of the aguathermal filter assembly according to the invention, the at least one filter unit is a disc filter unit.

An advantage of a disc filter unit, which in some countries or regions is also referred to as ring filter unit, provides an efficient and easily cleanable filter unit. Another advantage of a disc filter unit is that it is capable of filtering fluids that contain both relatively large particles as well as relatively small particles. This includes both rigid and soft particles like floating organic matter. it is noted that relatively large particles in this respect have a size in the range of hundreds of microns, whereas relatively small particles in this respect have a size that is less than about 50 microns.

In an embodiment of the aquathermal filter assembly according to the invention, the filter assembly may further comprise a fluid pump that is positioned upstream of the filter valve and that is configured for transporting fluid to be filtered under pressure to the filter unit.

An advantage of the assembly according to the invention is that the fluid pump with a lower maximum power output can be provided compared to the known aguathermal filter assemblies. Such traditional filter assemblies often contain several off-the-shelf products, including fluid pumps, that are not designed to cooperate. As a result, the hydraulic resistances in such assemblies are significantly higher. In addition, the fluid pump is also used to provide the backwash pressure, which requires a large maximum power output.

In an embodiment of the aquathermal filter assembly according io the invention, the assembly may comprise a plurality of filter units, filter valves and backwash valves, and wherein each of the plurality of filter units is associated with a filter valve and a backwash valve.

An advantage of providing multiple/a plurality of filter units is that a continuous filter operation can be performed. This is possible due to the fact that a part of the filter units can be operated in filter mode, whereas another part of the filter units can simultaneously be operated in backwash state or mode. Due to the use of a separate backwash channel and backwash pump, pressure separation between the filter units in different operational modes is possible. As a result, the power required for the backwashing is significantly lower than in known assemblies having a single fluid pump. It has been found that the (maximum) power output of a fluid pump may be reduced with 50% or more, and often even 75% or more. In addition, the hydraulic efficiency of the assembly is increased. Also, the configuration of the assembly according to the invention allows more freedom in design and therewith leads to a more compact assembly.

In an embodiment of the aquathermal filter assembly according to the invention, the filter units may be positioned in a parallel circuit, and the filter assembly may additionally comprise a first manifold that is positioned between the inlet and each filter valve associated with one of the filter units and a second manifold that is positioned between each backwash valve associated with one of the filter units and the backwash channel.

An advantage of providing the filter units in a parallel circuit is that each of the filter units, or groups thereof, may be separately switched between a filtering mode and a cleaning or backwash made. This allows continuous filtering and cleaning of the filter assembly rather than a semi-continuous or batch filtering, while simultaneously reducing the energy required to operate the filter assembly due to the separate fluid circuits.

In an embodiment of the aquathermal filter assembly according to the invention, the first manifold is configured to distribute a flow in the aquathermal filter assembly over the plurality of filter units and the second manifold is configured to merge flows from each of the plurality of filter units to a single flow into the backwash channel.

An advantage of providing a first and/or second manifold is that the fluid flow can more efficiently and precisely be regulated, leading to a more efficient assembly.

In an embodiment of the aquathermal filter assembly according to the invention, the aquathermal filter assembly may comprise a plurality of filter units that are positioned in a parallel circuit, further may comprise a first manifold that is positioned on the first side of the filter units and a second manifold that is positioned on the second side of the filter units. The at least one filter valve may be positioned between the inlet channel and the first manifold and the at least one backwash valve may be positioned between the backwash channel and the second manifold, The assembly may further comprise an outlet valve that is positioned between the second manifold and the outlet channel and a backwash discharge valve that is positioned between the first manifold and the backwash discharge channel. In the filtering mode the filter valve and the outlet valve are in an open state and the backwash valve and the backwash discharge valve are in a closed state, and in the backwash mode the backwash valve and the backwash discharge valve are in an open state and the filter valve and the outlet valve are in a closed state.

An advantage of the abovementioned embodiment is that a plurality of valves can be operated simultaneously. Another advantage is that ‘standard’ valves can be used rather than more complex three-way valves (that often also require more maintenance}.

A further advantage is the capacity of the filter assembly can easily be increased, since 5 the manifolds and associated filter units are placeable as a filter section. The manifolds of different filter sections can easily be connected to each other to form a filter assembly with a larger capacity.

In an embodiment of the aquathermal filter assembly according to the invention, the assembly may comprises a number of clusters of filter units, wherein each cluster comprises one or more filter units, a plurality of filter valves, wherein each filter valve is associated with a cluster and a plurality of backwash valves, wherein each backwash valve is associated with a cluster. Each cluster of filter units is switchable between a filtering mode and a backwash mode.

An advantage of providing clusters of filter units is that a continuous filter operation can be performed. This is possible due to the fact that it can be decided for each cluster separately whether it is operated in the filter mode or the backwash mode at a predetermined moment in time. A further advantage is that, due to the use of a separale backwash channel and backwash pump, pressure separation between the clusters in different operational modes is possible. As a result, the power required for the backwashing is significantly lower than in known assemblies having a single fluid pump. It has been found that the (maximum) power output of a fluid pump may be reduced with 50% or more, and often even 75% or more. In addition, the hydraulic efficiency of the assembly is increased. Also, the configuration of the assembly according to the invention allows more freedom in design and therewith leads to a more compact assembly.

In an embodiment of the aguathermal filter assembly according to the invention, the clusters are positioned in a parallel circuit, and the filter assembly comprises a first manifold and a second manifold. The first manifold is positioned between the inlet and the filter valves associated with a cluster and the second manifold is positioned between the backwash valves associated with a cluster and the backwash channel.

An advantage of providing a first and/or second manifold is that the fluid flow to each of the clusters can more efficiently and precisely be regulated, leading to a more efficient assembly. Another advantage is that a more detailed monitoring and control can be exercised over the different clusters.

In an embodiment of the aquathermal filter assembly according to the invention, the first manifold is configured to distribute a flow in the aquathermal filler assembly over the number of clusters of filter units and the second manifold is configured to merge flows from the clusters of filter units to a single flow into the backwash channel.

In an embodiment of the aguathermal filter assembly according to the invention, the assembly further comprises an aguathermal intake filter according to the invention, wherein the aquathermal intake filter is positioned at or upstream of the inlet.

An advantage of providing a combination of the aquathermal intake filter according to the invention and the aquathermal filter assembly according to the invention is that it provides a very efficient and effective filtering. This in turn reduces the wear on the aguathermal system in which it is applied.

The invention also relates to an aquathermal intake filter unit for an aguathermal system, the filter unit comprising: - afilter screen that surrounds an inner space, wherein the inner space has a length and a width; - a water outlet that is operatively connected to the inner space and that is configured to discharge filtered water from the aguathermal intake filter unit; - at least one cleaning nozzle that is positioned in the inner space and that is directed towards the filter screen to supply cleaning liquid to the filter screen; wherein a distance between the at least one nozzle, preferably an outlet thereof, and the filter screen is in the range of 1% to 30% of the filter width.

An advantage of the filter unit according to the invention is that, due to the small distance between the nozzle and the filter screen, the required backwash pressure is reduced.

It has been found that, with the abovementioned distances, the backwash pressure may be as low as 1.0 — 2.0 bar, and preferably can be reduced to about 1.5 bar. As a result, a separate backwash pump is not required, because the required pressure can be provided by the existing (main) pump associated with the system.

A further advantage is that, due to the proximity of the cleaning nozzles to the screen and the lower backwash pressure, less energy is required to operate the filter unit, leading to a reduction of the carbon footprint of the filter unit and, consequently, the aguathermal system.

An even further advantage is that the investment and operation costs are reduced due to the lower backwash pressure and the fact that the need for a backwash pump is obviated.

In an embodiment of the aquathermal intake filter according to the invention, the distance between the at least one nozzle and the filer screen is in the range of 2% to 20% of the filter width, preferably in the range of 3% to 15% of the filter width and more preferably in the range of 3% to 10% of the filter width.

The backwash pressure is reduced at closer distance, whereas the area of the filter screen that is covered by the cleaning fluid is also reduced. The abovementioned ranges provide a good balance between the backwash pressure to be used and the area on the filter screen that can be covered with cleaning fluid.

In an embodiment of the aquathermal intake filter according to the invention, the at least one cleaning nozzle comprises a plurality of cleaning nozzles.

An advantage of providing a plurality of cleaning nozzles is that it provides an even more homogenous cleaning. Another advantage is that it provides an even higher coverage of the filter screen. A further advantage is that it allows a more precise control over the (local) pressure exerted on the filter screen by the nozzles.

In an embodiment of the aquathermal intake filter according to the invention, the plurality of cleaning nozzles is positioned on a line that extends in the height direction of the inner space and preferably parallel to a central axis of the inner space.

An advantage of the abovementioned embodiment is that an evenly distributed pressure of the flow of cleaning liquid to the filter screen is achieved, leading to a more precise control over the (local) pressure exerted on the filler screen. Another advantage is that it provides an even higher coverage of the filter screen.

In an embodiment of the aquathermal intake filter according to the invention, the filter screen is a cylindrical filter screen having a filter diameter, and the diameter is the width.

An advantage of a cylindrical filter screen is that it can easily be rotated relative to the nozzle or nozzles, which simplifies the cleaning action. In addition, a cylindrical filter screen can more easily be manufactured. Another advantage is that a cylindrical filter screen has a relatively high resistance against bending and/or buckling.

In an embodiment of the aguathermal intake filter according to the invention, a distance between the at least one nozzle, preferably an outlet thereof, and the screen is in the range of 0.1 to 10 centimeter, preferably in the range of 0.1 to 8 centimeter, more preferably in the range of 0.5 to 5 centimeter and most preferably about 3 centimeter.

An advantage of the filter unit according to the invention is that, due to the small distance between the nozzle and the filter screen, the required backwash pressure is reduced. it has been found that, with the abovementioned distances, the backwash pressure may be as low as 1.0 — 2.0 bar, and preferably can be reduced to about 1.5 bar. As a result, a separate backwash pump is not required, because the required pressure can be provided by the existing (main) pump associated with the system.

A further advantage is that, due lo the proximity of the cleaning nozzles to the screen and the lower backwash pressure, less energy is required to operate the filter unit, leading to a reduction of the carbon footprint of the filter unit and, consequently, the aquathermal system.

In an embodiment of the aquathermal intake filter according to the invention, the at least one cleaning nozzle and the filter screen are rotatable relative to each other.

An advantage of this embodiment is that the at least one cleaning nozzle is capable of cleaning the entire circumference of the filter screen, while simultaneously allowing the filter to be used for filtering water.

In a preferred embodiment, at least the filter screen is rotatable around a central axis, such that the filter screen rotates past the cleaning nozzle for cleaning. Optionally, the at least one cleaning nozzle may also be rotatable, wherein the at least one cleaning nozzle and the filter screen are rotatable independently of each other.

In an embodiment of the aquathermal intake filter according to the invention, the at least one nozzle is part of a nozzle assembly that further comprises a cleaning fluid inlet having an inlet axis, wherein the cleaning fluid inlet is connected to each of the at least one nozzles, and a spray angle adjustment element that is configured to allow the at least one nozzle to rotate over a predetermined tangential angle relative to the inlet axis. The predetermined angle preferably is in the range of 1° to 180°, preferably in the range of 5° to 150° and more preferably in the range of 5° to 135°.

An advantage of a spray angle adjustment is that both the distance between the at least one nozzle and the filter screen and/or the angle of contact of the cleaning fluid with the filter screen can be adjusted. This is advantageous, because it allows the pressure exerted by the cleaning fluid on the filter screen to be adjusted to a certain extent.

A further advantage is that adjustment of the spray angle also effects the rotational force exerted on the filter screen, thus allowing optimization of propulsion forces in relation to the cleaning force exerted on the filter screen.

Another advantage is that the nozzle assembly can be applied to filter units of different sizes and/or shapes, because the direction and angle of contact can be adjusted to provide the correct pressure to the cleaning fluid.

In an embodiment of the aquathermal intake filter according to the invention, the outlet may comprise a quick release coupling that is configured to couple the outlet to an aquathermal assembly or aquathermal system.

An advantage of a quick release coupling is that the coupling can easily be connected and/or disconnected even though it is positioned near or even under the surface of the body of water.

Another advantage is that it is more compact than a conventional fiange-and-bolt connection that is used in existing filter units to connect it to an aquathermal system.

It is noted that the term ‘quick release’ means in the present application is a coupling that connectable and/or disconnectable in a very limited time frame and/or using a limited amount of tools, In particular, it is a coupling that can easily be (dis)connected under water and/or near the water surface, and comprises only a limited number, for example two or three, connectors that need to be (dis)connected. This is not possible with the present flange-and-

bolt connections, which require a large number of bolts in order to provide a secure connection.

In an embodiment of the filter unit according to the invention, the quick-release coupling comprises a male connection element that is positioned on one of the outlet and the system to which the filter unit is to be connected and a female connection element that is positioned on the other of the outlet and the system to which the filter unit is to be connected.

In an embodiment of the filter unit according to the invention, the quick-release coupling comprises a sliding coupling, wherein the outlet comprises a flange that is slidably insertable in a female receiver of the system to which the filter unit is to be connected.

In an embodiment of the filter unit according to the invention, the quick-release coupling comprises a hinge-type closing, a latch-type closing or a clamp, preferably a push-pull toggle clamp.

In an embodiment of the aguathermal intake filter according to the invention, the aquathermal intake filter further may comprise two ends plates that are positioned on opposite ends of the filter screen, wherein the end plates are configured to seal off the inner space, and preferably wherein one of both end plates is provided with an opening to accommodate the outlet.

An advantage of providing end plates is that the filter forms a closed housing that surrounds the inner space. This increases filtering efficiency. Another advantage is that the end plates can be provided with openings and connectors for the outlet and/or an inlet that is connectable to the at least one nozzle. It is noted that the end plates do not necessarily fluidly seal the inner space from an environment. In other words, a small opening between the end plates and the filter screen and/or the inner space may still be present.

The invention further relates to an aquathermal system comprising: - an aguathermal intake filter unit according to the invention; - a fluid extraction pump for extracting fluid from a body of surface water; - one ormore heat exchangers that are positioned downstream of the fluid extraction pump and that are configured to exchange heat with the fluid; and - a recirculation channel that is configured to return the fluid after exchanging heat to the body of surface water.

The aquathermal system according to the invention provides similar effects and advantages as the aquathermal intake filter unit and/or the aquathermal filter assembly according to the invention. Embodiments described in relation to the aguathermal intake filter unit and/or the aquathermal filter assembly according to the invention can be freely combined inthe system according to the invention.

In an embodiment of the aquathermal system according to the invention, the system may further comprises an aquathermal filler assembly according to the invention, the assembly being positioned between the aquathermal intake filter unit and the one or more heat exchangers, and the outlet channel being connected to an inlet of the one or more heat exchangers.

An advantage of positioning the aquathermal filter assembly between the heat exchangers and the aquathermal intake filter unit according to the invention provides an effective and efficient filtering of the fluid extracted from the body of water.

Another advantage is that the heat exchangers can at least partially be integrated with the aguathermal filter assembly according to the invention, leading to a more compact and efficient system.

In an embodiment of the aguathermal system according to the invention, an inlet of the backwash channel may be connected to the outlet channel downstream of the one or more heat exchangers.

An advantage of extracting the backwash fluid downstream of the heat exchangers is that the fluctuations in the quantity of fluid in the heat exchangers is obviated, allowing a substantially constant flow, This reduces variations in heat exchange and efficiency of the heat exchangers. This also results in a more stable heat exchange and thus a more constant output. When the backwash channel is positioned in the outlet channel at a point downstream of one or more heat exchangers for extracting backwashing fluid, the backwashing fluid will at that point have already transferred its heat to the heat exchanger.

The invention further relates to an aquathermal system comprising: - an aquathermal filter assembly according to the invention; - a fluid extraction pump for extracting fluid from a body of surface water; - one ormore heat exchangers that are positioned downstream of the fluid extraction pump and that are configured to extract heat from the fluid; and - a recirculation channel that is configured to return the cooled fluid to the body of surface water.

The aguathermal system according to the invention provides similar effects and advantages as the aquathermal intake filter unit and/or the aquathermal filter assembly according to the invention. Embodiments described in relation to the aquathermal intake filter unit and/or the aguathermal filter assembly according to the invention can be freely combined in the system according to the invention.

In an embodiment of the aquathermal system according to the invention, the system may further comprise an aquathermal intake filter unit according to the invention that is positioned between the assembly and the one or more heat exchangers.

The invention also relates to a method for filtering a fluid, the method comprising the steps of:

- providing an aguathermal intake filter according to the invention and/or providing an aguathermal filter assembly according to the invention; and - filtering a fluid using the intake filter and/or the filter assembly.

The method for filtering according to the invention provides similar effects and advantages as the aquathermal intake filter unit, the aquathermal filter assembly and/or the aquathermal system according to the invention. Embodiments described in relation to the aquathermal intake filter unit, the aquathermal filter assembly and/or the aquathermal system according to the invention can be freely combined in the method for filtering according to the invention.

The invention also relates to a method for exchanging heat with a body of surface water, the method comprising: - providing an aguathermal system according to the invention; - extracting water from a surface body using the extraction pump; - filtering the water using the aquathermal intake filter and/or the aguathermal filter assembly; - extracting heat from and/or supplying heat to the filtered water using a heat exchanger; and - discharging the water to the body of water.

The method for exchanging heat according to the invention provides similar effects and advantages as the aquathermal intake filter unit, the aquathermal filter assembly and/or the aquathermal system according to the invention. Embodiments described in relation to the aguathermal intake filter unit, the aquathermal filter assembly and/or the aquathermal system according to the invention can be freely combined in the method for exchanging heat according to the invention.

In an embodiment of the method for exchanging heat according to the invention, the method may further comprise the step of backwashing one or more filter units of the aquathermal filter assembly using the backwash pump and the backwash channel.

An advantage of using a separate backwash pump in a separate backwash channel is that the filtering and the backwashing can be separated process steps. As a result, the (total) energy required to perform both steps is significantly lower, therewith increasing the energetic and hydraulic efficiency of the method. This is mainly due to the fact that the filtering mode can be performed at a low pressure, whereas the backwash mode can be performed at high pressure. This is contrary to the known filter assemblies, in which both the filtering mode and the backwash mode are performed at the same (high) pressure.

Another advantage is that the method provides a more precise control over the backwashing and filtering steps. A further advantage is that the required pumps can be provided with a lower maximum power.

In an embodiment of the method for exchanging heat according to the invention, the step of backwashing one or more filter units may comprise extracting backwashing fluid from the outlet channel at a point downstream of the one or more heat exchangers.

An advantage of extracting the backwash fluid downstream of the heat exchangers is a substantially constant flow through the heat exchangers is provided. This results in a more stable heat exchange and an increased efficiency of the heat exchangers.

Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which:

Figures 1a and 1b shows a schematic view of a first example of an aquathermal filter assembly according to the invention;

Figures 2a and 2b shows a schematic view of a second example of an aquathermal filter assembly according to the invention;

Figure 3 shows a perspective view of an example of an aquathermal intake filter according to the invention in which the filter screen is obviated;

Figure 4 shows a perspective view of the example of figure 1 from a different direction with the filter screen;

Figure 5a shows a side view of the example of figure 3, in which the filter screen is shown as dotted lines;

Figure 5b shows a front view of the example of figure 3;

Figure 6a shows 4 cross sectional along a line Il — Il in figure 4;

Figure 6b shows a schematic view of an example of a control unit for the example shown in figure 6a;

Figure 7 shows a schematic view of an aguathermal system according to the invention; and

Figure 8 shows a schematic view of a second example of an aquathermal system according to the invention;

Figure 9 shows a schematic view of an example of a method for exchanging heat with a body of surface water according to the invention.

In an example (see figures 1a, 1b), aquathermal filter assembly 100 comprises, when viewed in filter flow direction F, inlet channel 142, a plurality of filter units 144 and outlet channel 146. In this example, each filter unit 144 is connected to filter valve 148 via connecting channel 144a and is further connected to backwash valve 150 via connection channel 144b.

Filter valve 148 is connected to inlet channel 142 by means of filter channel 147, whereas downstream valve 150 is connected to channel 146 by means of downstream channel 150.

Inlet channel 142, filter units 144, outlet channel 146 and both valves 148, 150 together form first or filter flow circuit F in which liquid to be filtered can be filtered. Aquathermal filter assembly 100 further comprises filter pump 158 that in this example is positioned upstream of inlet channel 142 and that is configured to be connected to a source of liquid, most of the times water, to be filtered (not shown).

Aduathermal filter assembly 100 further comprises backwash channel 152 that is connected with first end 152a to backwash valve 150. In this example, first end 1523 in fact comprises four first ends 152a, each of which is connected to an associated backwash valve 150. Second end 152b is connected to outlet channel 148, and in this example near outer end 146a thereof. Aquathermal filter assembly 100 further comprises backwash pump 154 that is positioned in backwash channel 152. Assembly 100 further also comprises backwash discharge channel 156 that extends from filter valve 148 to backwash outlet 140. The combination of backwash channel 152, valves 148, 150, and backwash discharge channel 156 forms second or discharge flow circuit D. This means that filter units 144 as well as filter valve 148 and backwash valve 150 are part of both filter flow circuit F and backwash flow circuit D. In this example, filter units 144 are connected in a parallel configuration, which means that each filter unit 144 can be operated independently by controlling associated filter valve 148 and associated downstream valve 150.

First opening 168 of each filter valve 148 is connected to inlet channel 142, or more specifically, to first manifold 164. Second opening 170 is connected to associated filter unit 144, whereas third opening 172 is connected to backwash discharge channel 152.

Furthermore, first opening 174 of backwash valve 150 is connected to associated filter unit 144 and second opening 176 is connected to outlet channel 146. Third opening 178 is connected to backwash channel 152, and more specifically to first end 152a thereof.

In a second example (see figures 2a, 2b), aquathermal filter assembly 200 comprises, when viewed in filter flow direction F, inlet channel 242, a plurality of filter units 244 and outlet channel 246. In this example, filter units 244 are divided in first cluster 260 and second cluster 262. Filter units 244 of each cluster 260, 262 are connected to inlet channel 242 by means of an associated first manifold 264. Similarly, all filter units 242 of each cluster 260, 262 are connected to outlet channel 246 by means of an associated second manifold 266.

Each filter valve 248 is connected to inlet channel 242 via connecting channel 247, whereas each backwash valve 250 is connected to outlet channel 246 via connection channel 249. This means that each cluster 260, 262 can be controlled independently, yet all filter units 244 in a single cluster 260, 262 are controlled all together (and substantially simultaneously). inlet channel 242, filter units 244, first and second manifolds 264, 266, outlet channel 246 and both valves 248, 250 together form first or filter flow circuit F in which liquid to be filtered can be filtered. Aquathermal filter assembly 200 further comprises filter pump 258 that in this example is positioned upstream of inlet channel 242 and that is configured to be connected to a source of liquid, most of the times water, to be filtered (not shown).

Aguathermal filter assembly 200 further comprises backwash channel 252 that is connected with first end 252a to backwash valve 250. In this example, first end 252a in fact comprises four first ends 252a, each of which is connected to an associated backwash valve 250. Second end 252b is connected to outlet channel 246, and in this example near outer end 246a thereof. Aquathermal filter assembly 200 further comprises backwash pump 254 that is positioned in backwash channel 252. Assembly 200 further also comprises backwash discharge channel 256 that extends from filter valve 248 to backwash outlet 240. The combination of backwash channel 252, valves 248, 250, and backwash discharge channel 256 forms second or discharge flow circuit D. This means that filter units 244 as well as filter valve 248 and backwash valve 250 are part of both filter flow circuit F and backwash flow circuit D. In this example, the clusters 260, 262 are connected in a parallel configuration, which means that each cluster 260, 262 can be operated independently by controlling associated filter valve 248 and associated downstream valve 250.

First opening 268 of each filter valve 248 is connected 10 inlet channel 242. Second opening 270 is connected to all associated filter units 244 by means of first manifold 264, whereas third opening 272 is connected to backwash discharge channel 256. Furthermore, first opening 274 of backwash valve 250 is connected to all associated filter units 244 by means of second manifold 266. Second opening 276 is connected to outlet channel 246, Third opening 278 is connected to backwash channel 252, and more specifically to first end 252a thereof.

During operation, each filter unit 144, 244 of aquathermal filter assembly 100, 200 can be switched between a filtering mode, in which a flow of fluid to be filtered is filtered and a cleaning or backwash mode in which filter unit 144, 244 is cleaned by means of backwashing.

In the second example (see figures 2a, 2b), all filter units 244 of a cluster 260, 262 are in the same mode at a given time. In a filtering mode of filter unit 144, 244 (see figures 1a, 1b, 2a, 2b), first opening 168, 268 and second opening 170, 270 of associated filter valve 148, 248 are in an open state, allowing fluid to be filtered to flow from inlet channel 142, 242 to filter unit 144, 244 for filtering. Third opening 172, 272 of associated filter valve 148, 248 is in a closed state, in which flow into backwash discharge channel 156, 256 is substantially prevented. In the filtering mode first opening 176, 276 and second opening 178, 278 of associated backwash valve 150, 250 are also in an open state to allow filtered fluid to flow from filter unit 144, 244 towards outlet channel 148, 248. Third opening 178, 278 of associated backwash valve 150, 250 is in a closed state, thus substantially preventing fluid to flow from backwash channel 152, 252 into backwash valve 150, 250 and filter unit 144, 244. As a result,

fluid to be filtered can flow from inlet channel 142, 242 through filter unit 144, 242, in which it is filtered, and subsequently to outlet channel 146, 246 to be discharged.

In a backwash mode of filter unit 144, 244 (see figures 1a, 1b, 2a, 2b), the fluid flow through filter unit 144, 244 is reversed compared to the filtering mode. In this mode, filtered fluid is drawn from outlet channel 146, 246 near end 146a, 246a thereof, into second end 152b, 252b of backwash channel 152, 252. Backwash pump 154, 254 is used to, under pressure, transport the fluid drawn into backwash channel 152, 252 towards first end or ends 152a, 252a thereof, each of which is connected to an associated backwash valve 150, 250.

Third opening 178, 278 of associated backwash valve 150, 250 is in an open state, allowing the fluid to flow into filter unit 144, 244. To that end, first opening 176, 276 of associated backwash valve 150, 250 is in an open state, whereas second opening 178, 278 that is connected to outlet channel 146, 246 is in a closed state. Thus, fluid flows from backwash channel 152, 252 into filter unit 144, 244 to backwash (i.e. clean) filter unit 144, 244. The backwash fluid flow subsequently flows into filter valve 148, 248 through second opening 170, 270 thereof. In the backwash mode, third opening 172, 272 of associated filter valve 148, 248 is in an open state, allowing the flow from filter unit 144, 244 to flow into backwash discharge channel 156, 256 for discharge. At the same time, first opening 168, 268 of associated filter valve 148, 248 is in a closed state, thus preventing fluid flow from filter unit 144, 244 into inlet channel 142, 244.

In case only a single filter unit 144 is used, backwash pump 154 is preferably not operated during a filtering mode of aquathermal filter assembly 100 and filter pump 158 is preferably not operated during a backwash or cleaning mode of aquathermal filter assembly 100. In case a plurality of filter units 144 is used, both filter pump 158 and backwash pump 154 may be operated simultaneously, because a part of filter units 144 may be in backwash mode, whereas another part of filter units 144 is a filtering mode.

In use of aquathermal filter assembly 100, 200 liquid to be filtered is provided to inlet channel 142, 242 using filter pump 158, 258, which filter pump 158, 258 provides the liquid or fluid under a working pressure to filler valves 148, 248 and subsequently filter units 144, 244 that are associated with filter valves 148, 248.

In the first example, filter units 144 are in this example divided in four groups, each comprising a single filter unit 144. First group 157, second group 159 and third group 161 of filter units 144 is provided in filtering mode (see figure 1a). Fourth group 163 is provided in backwash mode. This allows a continuous filtering process io be performed. The liquid provided to the filter valves 148 is provided to filter units 144 of first, second and third groups 157, 159, 181 for filtering, whereas the first openings 170 of filter valves 148 of fourth group 163 are closed to prevent the inlet of liquid. The liquid is filtered in first, second and third groups 157, 159, 161 of filter units 144 and is then provided, via backwash valve 150, to outlet channel 146 for further use.

Part of the filtered liquid is extracted from outlet channel 146 via second end 152b into backwash channel 152. This liquid is provided to backwash valves 150 of fourth group 163 of filter units 144 and is subsequently used to clean filter units 144 of fourth group 163 by backwashing. The flow in fourth group 163 of filter units 144 (i.e. from outlet to inlet) is therewith substantially opposite to the flow direction of first, second and third groups 157, 159, 161 of filter units 144 (i.e. from inlet to outlet). The backwash flow is subsequently, via filter valves 148, discharged into backwash discharge channel 156 for discharging from the assembly.

After a predetermined period of time, first group 159 of filter units 144 is switched from the filtering mode to the backwash mode (see figure 1b), while fourth group 163 of filter units 144 is simultaneously switched from the backwash mode to the filtering mode (see figure 1b).

After a further predetermined period of time, subsequently second and third groups 159, 161 are switched to backwash mode. As such, during operation, one of four groups 157, 159, 161, 163 is in backwash mode, whereas the others are in filtering mode.

In the second example, filter units 244 are operated by means of clusters 260, 262.

During use in a first time period (see figure 2a), first cluster 260 is operated in backwash mode, whereas second cluster 262 is operated in filtering mode. This allows a continuous filtering process to be performed. The liquid provided to inlet channel 242 is provided to filter valve 248 of second cluster 262 and subsequently, via first manifold 264 to filter units 244 of second cluster 262. At the same time, first opening 270 of filter valves 248 of second cluster 262 is closed to prevent the inlet of liquid from inlet channel 242. The liquid is fillered in filter units 244 of first cluster 260 and is then provided, via backwash valve 250, to outlet channel 246 for further use.

Part of the filtered liquid is extracted from outlet channel 246 via second end 252b into backwash channel 252. This liquid is provided to backwash valve 250 of first cluster 260 and subsequently to filter units 244 to backwashing filter units 244 of first cluster 260. The backwash flow is subsequently, via filter valve 248 of first cluster 260, discharged into backwash discharge channel 256 for discharging from the assembly. The flow in first cluster 260 (i.e. from outlet to inlet) is therewith substantially opposite to the flow direction of second cluster 262 (i.e. from inlet to outlet). After a predetermined period of time, second cluster 262 is switched from the filtering mode to the backwash mode (see figure 2b), while first cluster 260 is simultaneously switched from the backwash mode to the filtering mode (see figure 2b). it is noted that in the abovementioned examples (see figures 1a, 1b, 2a, 2b), filter valves 148, 248 and backwash valves 150, 250 are all three-way valves. I is noted that a similar construction may also be achieved using multiple other valves or valve types.

In an example, aguathermal intake filter 2 (see figures 3 to 6a) comprises filter screen 4 that surrounds inner space 6 and that is delineated at the outer ends by end plates 8, 10.

Filter screen 4 in this example is supported on support plates 7, 9, in this example annular plates 7, 9, that extend around end plates 8, 10. Aquathermal intake filter 2 is in this example a cylindrical filter that extends over length L and has diameter D. Diameter D can as such be seen as a width of filter 2. Aquathermal intake filter 2 further comprises water outlet 12 that in this example is provided as outlet tube 12. Outlet tube 12 extends substantially over length L inside inner space 6 and extends through end plate 8 and over a predetermined length Lan beyond end plate 8. Outer end 14 of outlet tube 12 is provided with quick release coupling 16 that in this example is a sliding coupling 16.

The part of outlet tube 12 that extends within inner space 6 in this example is provided with a number of openings 18 that allow filtered water to enter tube 12 and be discharged through the outlet at outer end 14 of outlet tube 12. It is noted that other configurations may also be possible, such as an open inner space 6 {with water outlet 12 only having outlet length

Lu) Or with a gaze screen as filter outlet within inner space 6.

Aguathermal intake filter 2 is in this example further provided with a plurality of cleaning nozzles 20 that are provided on fluid supply 22. Fluid supply 22 extends from first end 24 through end plate 8 towards second end 26 that is positioned inside inner space 6. First end 24 can be coupled to a source of cleaning fluid, for example water, that is used to clean filter screen 4. In this example, fluid supply 22 is provided as tubular fluid supply 22 that extends along inlet axis A and substantially parallel to water outlet 12.

In this example, fluid supply 22 is rotatable around inlet axis A over a predetermined angle by means of motor 24 that is controlled by control unit 26 (see figure 6b). The angle of rotation a is limited by spray angle adjustment element 28, which in this example limits the rotation of fluid supply 22 (and therewith nozzles 20) to a spray angle adjustment in the range of 5° to 135° Nozzles 20, fluid supply 22 and spray angle adjustment element 28 together form nozzle assembly 30, which also may include motor 24.

Each of the plurality of nozzles 20 is positioned at a predetermined distance R or distance range R to filter screen 4. Distance R in this example is, due to the rotation of nozzles 20 around axis A, a range of distances all of which are lower than 20% of diameter D.

Filter screen 4 is in this example further rotatably positioned around central axis C, which allows filter screen 4 to be cleaned using a flow of cleaning fluid from nozzles 20. During use, filter screen 4 rotates past nozzles 20 and cleaning fluid is sprayed against filter screen 4 to dislodge debris and/or pollution that is collected on filter screen 4.

In order to separate inner space 6 off from the environment, a small opening or slit 32, 34 is positioned between the respective end plate 8, 10 and filter screen 4, and more specifically between support plates 7, 9 that are connected to filter screen 4 and the respective end plate 8, 10. Opening or slit 32, 34 in this example is equal to or smaller that a hole size of a perforation of filter screen 4. In another, not shown example a seal may also be used in opening or slit 32, 34 to seal off the opening.

In an example of aquathermal system 301 (see figure 7), aquathermal system 301 comprises aquathermal intake filter 302, which in this example is essentially similar to the aquathermal intake filter 2 described above. System 301 further comprises aquathermal filter assembly 300. Assembly 300 is virtually similar to the first example of the assembly 100 described above. For both the aquathermal intake filter 302 and assembly 300 similar reference signs are used in the description of system 301, representing similar components.

Naturally, system 301 may also be provided with aquathermal filter assembly 200 as described above, or with another filter assembly falling with the scope of the invention. Filter assembly 300 comprises, when viewed in filter flow direction F, inlet channel 342, a plurality of filter units 344 and outlet channel 346, In this example, each filter unit 344 is connected to filter valve 348 via connecting channel 344a and is further connected to backwash valve 350 via connection channel 344b. Filter valve 348 is connected to inlet channel 342 by means of filter channel 347, whereas downstream valve 350 is connected to channel 346 by means of downstream channel 350. Aquathermal filter assembly 300 further comprises filter pump 358 that in this example is positioned upstream of inlet channel 342 and that is connected to aquathermal intake filter 302 to take in pre-filtered water from a body of water, such as a river, lake, stream or other suitable body of water. Aquathermal filter assembly 300 further comprises backwash channel 352 that is connected to backwash valve 350 and to outlet channel 346. Aquathermal filter assembly 300 further comprises backwash pump 354 that is positioned in backwash channel 352. Assembly 300 further also comprises backwash discharge channel 356 that extends from filter valve 348 to backwash outlet 340.

Aquathermal system 301 further comprises heat exchanging unit 380, in this case heat exchanger 380, having first inlet 382 that is connected to outlet channel 246. First outlet 384 of heat exchanger 380 is discharge outlet 384 or recirculation channel 384 to discharge water to an external environment or recirculate it to the body of water from which the water was extracted. In this example of system 301, second end 352b of backwash channel 352 is connected to first outlet 384 of heat exchanger 380 rather than to first inlet 382 thereof. This provides the advantage that a more stable flow into the first side 381 of heat exchanger 380 is achieved. Second side of heat exchanger 380 is connected, via second inlet 386 and second outlet 388 with heating and/or cooling system 390. in this example, heat exchanger 380 is a counterflow heat exchanger. It is noted that any other type of heat exchanger or combinations of different heat exchangers may also be used for system 301. Heating and/or cooling system 390 may comprise several other components, including further heat exchangers, heating or cooling units and/or pipelines. Such components are known in the art and not discussed any further.

In a second example (see figure 8), aquathermal system 401 comprises a third example of an aquathermal filter assembly. Aquathermal filter assembly 400, when viewed in filter flow direction F, comprises inlet channel 442, a plurality of filter units 444 and outlet channel 4486. In this example, filter units 444 are divided in four groups 457, 459, 461, 463 of filter units 444, with each group 457, 459, 461, 463 of filter units 444 being connected to an associated first manifold 464 and an associated second manifold 466. Filter units 444 of each group 457, 459, 461, 463 are provided in a parallel configuration, although they are preferably operated simultaneously.

Each filter valve 448 is connected to inlet channel 442 by means of filter channel 447 and is, on a second side, connected to first manifold 464. Filer valve 448 is therewith positioned between inlet channel 442 and (a first end of) first manifold 464. In this example, first manifold 464 is further connected to backwash discharge valve 492 that is positioned on an end of first manifold 464 that is opposite the end to which filter valve 448 is connected.

Backwash discharge valve 492 is therewith connected between first manifold 464 and backwash discharge channel 456.

In this example, aguathermal filter assembly 400 further comprises, for each group 457, 459, 461, 463 also backwash valve 450 that is positioned between backwash channel 452 and an end of second manifold 466. In addition, second manifold 466 is further connected to outlet valve 494 that is positioned on an end of second manifold 466 that is opposite the end to which backwash valve 450 is connected. Outlet valve 494 is therewith positioned between second manifold 466 and outlet channel 446.

Backwash channel 452 is in this example of system 401 connected to outlet channel 484 of heat exchanger 480 with second end 452b. Aguathermal filter assembly 400 further comprises backwash pump 454 that is positioned in backwash channel 452.

Aquathermal system 401 further comprises heat exchanger 480 having inlet 482 that is connected to outlet channel 446 and in this case forms a seamless transfer between the two. Heat exchanger 480 further comprises, on a second side, inlet 486 and outlet 488, which are connected to a (further) heating and/or cooling system 490. After fluid F has exchanged heat in heat exchanger 480, the fluid is discharged via outlet 484 towards aquathermal intake filter 402, or alternatively is provided to backwash channel 452.

Aguathermal system 401 in this example comprises four aquathermal intake filters 402 that are positioned in a body of water W, such as a stream, a body of effluent water of a waste water treatment facility or another suitable fluid source W.

Aquathermal intake filters 402 are connected, in this example in pairs, to regulator valves 496, which can be used to control the operation of quathermal intake filters 402. In this example, each group of quathermal intake filters 402 is used either for extraction of {in this example) water.

In an example of method 1000 for exchanging heat with a body of surface water (see figure 9), method 1000 comprises the step of providing 1002 an aguathermal system according to the invention. Preferably, the system comprises both an aquathermal intake filter according to the invention and an aquathermal filter assembly according to the invention.

Method 1000 may further comprise the step of extracting 1004 water from a surface body using the extraction pump. The method further comprises at least one of the two steps of filtering 1006 the water using the aquathermal intake filter and filtering 1008 the water using the aquathermal filter assembly. Preferably, both steps are taken. Subsequently, method 1000 comprises the step of extracting heat 1010 from and/or supplying heat to the filtered water using a heat exchanger and discharging 1012 the water to the body of water. Method 1000 may optionally comprise the step of backwashing 1014 one or more filter units of the aquathermal filter assembly using the backwash pump and the backwash conduit. This optional step can only be performed in case step 1008 is performed as well.

The present invention is by no means limited to the above described preferred embodiments and/or experiments thereof. The rights sought are defined by the following claims within the scope of which many modifications can be envisaged.

CLAUSES

1. Aguathermal filter assembly, comprising: - an inlet channel that is operatively connected to a first side of at least one filter unit; - an outlet channel that is operatively connected to a second side of the at least one filter unit; - a backwash channel that is operatively connected to the second side of the at least one filter unit and that comprises a backwash pump; - a backwash discharge channel that is operatively connected to the first side of the at least one filter unit; - at least one filter valve that is positioned on the first side of the at least one filter unit; and - atleast one backwash valve that is positioned on the second side of the at least one filter unit; wherein the filter unit has a filtering mode, in which the associated filter and backwash valves are in a first position such that the inlet and the outlet are fluidly connected to each other, and a backwash mode in which the associated filter and backwash valves are in a second position such that the backwash channel and the backwash discharge channel are fluidly connected to each other. 2. Aguathermal filter assembly according to clause 1, wherein the assembly comprises a filter flow circuit comprising the inlet channel, the at least one filter unit and the outlet channel and a backwash flow circuit comprising the backwash channel, the at least one filter unit and the backwash discharge channel. 3. Aguathermal filter assembly according to clause 1 or 2, wherein the filter valve and the backwash valves are three-way valves, wherein the inlet channel and the backwash discharge channel are connected to the three-way filter valve, and wherein the outlet channel and the backwash channel are connected to the three-way backwash valve. 4. Aquathermal filter assembly according to any one of the preceding clauses, wherein a backwash channel inlet is positioned in the outlet channel. 5. Aquathermal filter assembly according to any one of the preceding clauses, wherein the at least one filter unit is a disc filter.

6. Agquathermal filter assembly according to any one of the preceding clauses, further comprising a fluid pump that is positioned upstream of the filter valve and that is configured for transporting fluid to be filtered under pressure to the filter unit.

7. Aquathermal filter assembly according to any one of the preceding clauses, wherein the assembly comprises a plurality of filter units, filter valves and backwash valves, and wherein each of the plurality of filter units is associated with a filter valve and a backwash valve.

8. Aquathermal filter assembly according to any one of the preceding clauses, comprising a plurality of filter units that are positioned in a parallel circuit, and wherein the filter assembly comprises:

- a first manifold that is positioned on the first side of the filter units, and - a second manifold that is positioned on the second side of the filter units;

wherein the at least one filter valve is positioned between the inlet channel and the first manifold, wherein the at least one backwash valve is positioned between the backwash channel and the second manifold, and wherein the assembly further comprises:

- an outlet valve that is positioned between the second manifold and the outlet channel; and

- a backwash discharge valve that is positioned between the first manifold and the backwash discharge channel; wherein in the filtering mode the filter valve and the outlet valve are in open state and the backwash valve and the backwash discharge valve are in a closed state, and wherein in the backwash mode the backwash valve and the backwash discharge valve are in open state and the filter valve and the outlet valve are in a closed state.

9. Agquathermal filter assembly according to any one of the preceding clauses, wherein the assembly comprises: - anumber of clusters of filter units, wherein each cluster comprises one or more filter units;

- a plurality of filter valves, wherein each filter valve is associated with a cluster;

- a plurality of backwash valves, wherein each backwash valve is associated with a cluster; and wherein each cluster of filter units is switchable between a filtering mode and a backwash mode.

10. Aquathermal filter assembly according to any one of the preceding clauses 1 to 7, wherein the filter units are positioned in a parallel circuit, and the filter assembly additionally comprises a first manifold that is positioned between the inlet and each filter valve associated with one of the filter units and a second manifold that is positioned between each backwash valve associated with one of the filter units and the backwash channel.

11. Aquathermal filter assembly according to clause 10, wherein the first manifold is configured to distribute a flow in the aquathermal filter assembly over the plurality of filter units and the second manifold is configured to merge flows from each of the plurality of filter units to a single flow into the backwash channel.

12. Aquathermal system comprising: - an aguathermal filter assembly according to one or more of the clauses 1 — 11; - a fluid extraction pump for extracting fluid from a body of surface water; - one or more heat exchangers that are positioned downstream of the fluid extraction pump and that are configured to extract heat from the fluid; and - a recirculation channel that is configured to return the cooled fluid to the body of surface water. 13. Aquathermal system according to clause 12, further comprising an aquathermal intake filter unit, the filter unit comprising: - afilter screen that surrounds an inner space, wherein the inner space has a length and a width; - a water outlet that is operatively connected to the inner space and that is configured to discharge filtered water from the aquathermal intake filter unit; - at least one cleaning nozzle that is positioned in the inner space and that is directed towards the filter screen to supply cleaning liquid to the filter screen; wherein: - a distance between the at least one nozzle, preferably an outlet thereof, and the filter screen is in the range of 1% lo 30% of the filter width; and - the aquathermal assembly is positioned between the aquathermal intake filter unit and the one or more heat exchangers, and the outlet channel being connected to an inlet of the one or more heat exchangers. 14. Aquathermal system according to clause 12 or 13, wherein an inlet of the backwash channel is connected to the outlet channel downstream of the one or more heat exchangers.

15. Aguathermal system according to any one of the clauses 12 to 14, wherein the at least one cleaning nozzle and the filter screen are rotatable relative to each other.

16. Aquathermal system according to any one of the clauses 12 to 15, wherein the at least one nozzle is part of a nozzle assembly that further comprises: - a cleaning fluid inlet having an inlet axis, wherein the cleaning fluid inlet is connected to each of the at least one nozzles;

- a spray angle adjustment element that is configured to allow the at least one nozzle to rotate over a predetermined tangential angle relative to the inlet axis, wherein the predetermined angle is in the range of 1° to 180°, preferably in the range of 5° to 150° and more preferably in the range of 5° to 135°.

17. Aquathermal system according to any one of the clauses 12 to 16, wherein the outlet comprises a quick release coupling that is configured to couple the outlet to an aguathermal assembly or aquathermal system.

18. Method for exchanging heat with a body of surface water, the method comprising: - providing an aquathermal system according to any one of the clauses 1210 17; - extracting water from a surface body using the extraction pump; - filtering the water using the aquathermal intake filter and/or the aguathermal filter assembly; - extracting heat from and/or supplying heat to the filtered water using a heat exchanger; and - discharging the water to the body of water. 19. Method according to claim 18, further comprising the step of backwashing one or more filter units of the aquathermal filter assembly using the backwash pump and the backwash conduit.

Claims

CONCLUSIONS

1. An aquathermy system comprising: - an aquathermy filter assembly, comprising: - at least one filter unit; - an inlet duct operatively connected to a first side of the at least one filter unit; - an outlet duct operatively connected to a second side of the at least one filter unit; - a cleaning duct operatively connected to a second side of the at least one filter unit and provided with a cleaning pump; - a cleaning outlet duct operatively connected to the first side of the at least one filter unit; - at least one filter valve positioned on the first side of the at least one filter unit; and - at least one cleaning valve positioned on the second side of the at least one filter unit; the filter unit having a filtering mode in which the associated filter and cleaning valves are in a first position such that the inlet and the outlet are in fluid communication with each other, and a cleaning mode in which the associated filter and cleaning valves are in a second position such that the cleaning channel and the cleaning output channel are in fluid communication with each other; and the system further comprising: - a liquid extraction pump for pumping liquid from a body of water; … one or more heat exchangers positioned downstream of the liquid extraction pump and arranged to exchange heat with the liquid; and - a recirculation channel arranged to return the cooled liquid to the body of water.

An aquathermy system according to claim 1, wherein the filter assembly comprises a filter flow circuit comprising the inlet channel, the at least one filter unit and the outlet channel and a cleaning circuit comprising the cleaning channel, the at least one filter unit and the cleaning outlet channel.

3. Aguathermie system according to claim 1 or 2, wherein the filter valve and the cleaning valve are three-way valves, wherein the inlet channel and the cleaning outlet channel are connected to the three-way filter valve, and wherein the outlet channel and the cleaning channel are connected to the three-way cleaning valve.

4. An aquathermic system according to any one of the preceding, wherein a cleaning channel inlet is positioned in the outlet channel at a position downstream of the one or more heat exchangers.

5. Aquathermy filter assembly according to any of the preceding, wherein the at least one filter unit is a disc filter.

6. Aquathermic system according to any of the preceding claims, further comprising a liquid pump arranged upstream of the filter valve and adapted to transport liquid to be filtered under pressure to the filter unit.

7. An aquathermy system according to any preceding claim, wherein the assembly comprises a plurality of filter units, filter valves and cleaning valves, and wherein each of the plurality of filter units is associated with a filter valve and a cleaning valve.

8. An aquathermy system according to any preceding claim, comprising a plurality of filter units positioned in a parallel circuit, and wherein the filter assembly comprises: - a first manifold positioned on the first side of the filter units; and - a second manifold positioned on the second side of the filter units; wherein the at least one filter valve is positioned between the inlet channel and the first manifold, and wherein the at least one cleaning valve is positioned between the cleaning channel and the second manifold, and wherein the assembly further comprises: - an outlet valve positioned between the second manifold and the outlet channel; and - a cleaning outlet valve positioned between the first manifold and the cleaning outlet channel; wherein, in the filtering state, the filter valve and the outlet valve are in an open state and the cleaning valve and the cleaning outlet valve are in a closed state, and wherein, in the cleaning state, the cleaning valve and the cleaning outlet valve are in an open state and the filter valve and the outlet valve are in a closed state.

9. Aquathermy system according to any of the preceding claims, wherein the assembly comprises:

- a plurality of clusters of filter units, each cluster comprising one or more filter units; - a plurality of filter valves, each filter valve being associated with a cluster; - a plurality of cleaning valves, each cleaning valve being associated with a cluster; and each cluster of filter units being switchable between a filtering state and a cleaning state.

10. Aquathermy system according to any one of the preceding claims 1 to 7, wherein the filter units are positioned in a parallel circuit, and wherein the filter assembly further comprises a first distributor disposed between the inlet and each filter valve associated with one of the filter units and a second distributor disposed between each cleaning valve associated with one of the filler units and the cleaning channel.

An aquathermy system according to claim 10, wherein the first distributor is adapted to distribute a flow in the aquathermy filter assembly over the plurality of filter units and the second distributor is adapted to combine all flows from each of the plurality of filter units into a single flow to the cleaning channel.

An aquathermic system according to any one of the preceding claims, further comprising an aquathermic suction filter unit, the aquathermic suction filter unit comprising: - a filter screen enclosing an interior space, the interior space having a length and a width; - a water outlet operatively connected to the interior space and adapted to discharge filtered water from the aquathermic suction filter unit; - at least one cleaning nozzle positioned in the interior space and directed towards the filter screen for supplying cleaning fluid to the filter screen; wherein a distance between the at least one nozzle, preferably an outlet thereof, and the filter screen is in the range of 1% to 30% of the filter width; and wherein the aquathermic filter assembly is positioned between the aquathermic suction filter unit and the one or more heat exchangers, and wherein the outlet duct is connected to an inlet of the one or more heat exchangers.

Aquathermic system according to claim 12, wherein the at least one cleaning nozzle and the filter screen of the aquathermic suction filter unit are rotatable relative to each other.

An aquathermic system according to any one of claims 12 or 13, wherein the at least one nozzle is part of a nozzle assembly further comprising: - a cleaning fluid inlet having an inlet axis, the cleaning fluid inlet being connected to each of the at least one nozzle; … a spray angle adjusting element adapted to rotate the at least one nozzle through a predetermined angle relative to the inlet axis, the predetermined angle being in the range of 1° to 180°, preferably in the range of 5° to 150° and more preferably in the range of 5° to 135°.

15. Aquathermic system according to any of the preceding claims 12 to 14, wherein the outlet comprises a quick coupling designed for connecting the outlet to an aquathermic assembly or an aquathermic system.

16. Method for exchanging heat with a body of water, the method comprising: - providing an aquathermic system according to any one of the preceding claims; - extracting water from the body of water using the extraction pump; - filtering the water using the aquathermic suction filter and/or the aquathermic filler assembly; … extracting heat and/or supplying heat to the filtered water using a heat exchanger; and - discharging the water to the body of water.

17. Method according to claim 16, further comprising the step of cleaning one or more filter units of the aquathermy filter assembly using the cleaning pump and the cleaning channel.