METHOD AND APPARATUS FOR PROVIDING COLD OR HOT WATER

Description

technical field

[0001] The present invention relates to a method of supplying cold water, in particular using rainwater to supply floor or wall-mounted air conditioning devices, or air humidification devices.

[0002] It also concerns an installation for the supply of cold water for the implementation of this process. Previous technique

[0003] Many countries around the world are experiencing more frequent, or even more severe, episodes of drought than in the past.

[0004] At the same time, the replenishment of groundwater, particularly during the winter, can prove to be more unpredictable, as was the case in France in 2021.

[0005] We observe that mobilizable water resources are decreasing even as water demand continues to increase.

[0006] However, several solutions are proposed.

[0007] For example, we can cite those aimed at saving water by supporting agricultural sectors in their adaptation to climate change, or those aimed at improving rainwater infiltration by de-sealing soils in urban areas.

[0008] We are also seeking to reduce the demand for drinking water for non-priority uses such as watering green spaces, washing cars or for domestic use such as supplying toilets or cleaning floors.

[0009] It is thus known to collect some of the rainwater to store it in a reservoir in order to reuse it in a controlled manner in space and time.

[0010] However, this rainwater is typically collected for purely domestic use in limited volumes.

[0011] Furthermore, we are familiar with the phenomenon of urban heat islands, which manifests itself as a difference of several degrees in temperature between a city and the surrounding rural or forest areas.

[0012] To mitigate the intensity of these heat islands, it has been proposed, where possible, to reduce mineral surfaces, which absorb solar radiation and store it during the day, and to plant vegetation in these urban spaces to provide shade.

[0013] Cooling the ambient air is another avenue being explored with interest.

[0014] For example, air humidification systems are implemented, including so-called "evaporative" paving stones, which have water retention properties and are supplied by capillary rise of water from buried pipes, to locally reduce the temperature by water evaporation.

[0015] For example, document EP3728958B1 discloses an urban cooling installation, comprising a water-retaining surface coating (70), disposed at the level of an area to be cooled (2), a water distribution network (60), a water supply system (30), connected to the water distribution network (60), a control system (40) configured to control the water supply system (30) to allow or prohibit the supply of water from the water distribution network (60), in which the control system (40) includes at least two separate sensors (50) configured to measure two different climatic parameters of the environment of the installation (1).The control system (40) is configured to control the supply system (30) based on the ground temperature in the area to be cooled (2) and the ground temperature in a reference area (3) without the water-retaining surface coating and adjacent to the area to be cooled (2). Such an installation includes, in particular, a water-retaining surface coating, located in an area to be cooled, a water distribution network, a water supply system connected to the water distribution network, and a control system configured to control the water supply system to allow or prevent the supply of water from the water distribution network, wherein the control system includes at least two separate sensors configured to measure two different climatic parameters of the installation's environment.

[0016] Thanks to such a control system comprising at least two separate sensors, it is possible to operate the cooling system more reliably by more precisely assessing the need for cooling in order to increase pedestrian comfort when desired without wasting water when it is unnecessary (column 2, paragraphs 8 and 9). In some embodiments, at least one water source is rainwater. This allows for the reuse of rainwater in a short cycle, thus limiting the use of potable water (column 3, paragraph 17).

[0017] Although they yield positive results in combating the urban heat island effect, such solutions are very water-intensive, making them unsuitable for addressing current water shortage problems.

[0018] There is therefore an urgent need for a pedestrian zone cooling installation to improve pedestrian comfort, the original design of which overcomes the disadvantages of the previous art outlined above. Object of the invention

[0019] The present invention aims to overcome the drawbacks of the prior art by proposing a method and installation for supplying cold water, simple in design and in operation, allowing the delivery of cold water in large quantities and cheaply.

[0020] Another object of the present invention is such a method and such an installation for supplying cold water not requiring an external energy source to produce cold water.

[0021] Another object of the present invention is such a process and installation having a low carbon footprint.

[0022] The present invention also aims at a cooling installation to increase the comfort of pedestrians in an urban area or the comfort of an individual in a room of their home. Description of the invention

[0023] To this end, the invention relates to a method for supplying cold water.

[0024] According to the invention, the following steps are carried out: determine, from among a plurality of tanks totally buried in the ground, at least one tank full of water, or partially filled with water, the temperature of whose contents is below a threshold temperature, keep isolated at least one of said buried tanks, filled with water whose temperature of contents is greater than or equal to said threshold temperature until the temperature of its contents falls below said threshold temperature, ensure that water whose temperature is less than said threshold temperature flows to at least one end-use point from said or at least one of said buried tanks thus determined, and said water is rainwater, drinking water, recycled wastewater, water from a watercourse such as a river, or a mixture of at least two of these waters.

[0025] This process takes advantage of the lower ground temperature in summer compared to ambient temperature to cool the water stored in each tank. Preferably, the cooling of the tank's contents therefore results solely from heat exchange with the surrounding ground. It is not a forced cooling method.

[0026] Of course, we will have previously determined the depth at which the tanks must be buried according to the nature of the thermal characteristics of the soil in question, in particular its diffusivity.

[0027] When said water thus stored is collected rainwater, the present process advantageously provides cheap and fully recyclable cold water.

[0028] Advantageously, said water is pressurized to supply said at least one end-use point from at least one reservoir.

[0029] According to a particular embodiment of this cold water supply process, the additional step of supplying water to one or more empty tanks, or when the temperature of their contents is above said threshold temperature, to one or more partially filled tanks, from said plurality of buried tanks, preferably, until they are full, is carried out.

[0030] According to another particular embodiment of this cold water supply process, said water being rainwater, it is filtered before supplying at least one of said underground reservoirs.

[0031] According to yet another particular embodiment of this cold water supply process, the said threshold temperature is equal to 14°C, even better equal to 12°C and even more preferably equal to 10°C.

[0032] According to yet another particular embodiment of this cold water supply process, supplying said at least one end-use point with water from at least one first underground reservoir, and detecting that the water level in said or at least one of said first reservoirs falls below a low threshold level, said or said first reservoirs are isolated and this or these first reservoirs are replaced by as many second underground reservoirs whose contents temperature is below said threshold temperature, so as to continue supplying said at least one end-use point.

[0033] According to yet another specific embodiment of this cold water supply process, the water is treated prior to its delivery to the final point of use to demineralize or soften it, or to eliminate pathogenic microorganisms. Sterilization of the water may also be carried out.

[0034] According to yet another embodiment of this cold water supply process, if the temperature of the water delivered to at least one end-use point is higher than a setpoint temperature, the water is cooled so that its temperature reaches the setpoint temperature before use.

[0035] According to yet another embodiment of this cold water supply process, said end-use point is a floor and / or wall-mounted air conditioning unit, or a device for cooling outside air.

[0036] According to yet another embodiment of this cold water supply process, the water supply to said at least one end-use point is ordered after analysis of several data measured locally by at least two sensors, possibly coupled with one or more meteorological data, and identification of a need for cooling, said sensors being selected from the group comprising a temperature probe, a humidity probe, an anemometer and combinations of these elements.

[0037] For illustrative purposes only, a humidity sensor is configured to measure the relative humidity of the air. This data is known to influence the perceived temperature. For example, it could be a hygrometer.

[0038] Similarly, it is advantageous to use an anemometer to measure wind speed, which also influences the perceived temperature.

[0039] In addition to an air temperature probe, a black globe temperature probe can also be used to measure radiation temperature in order to determine heat stress.

[0040] In yet another embodiment of this cold water supply process, one or more releases of cooled or heated water are made for use in irrigation or cleaning. Advantageously, the system can then be used not as a closed-loop system, but for irrigation or cleaning purposes.

[0041] More generally, the present invention allows for the automatic management of transfers of cold water to hot areas and vice versa, of hot water to cold areas.

[0042] Thus, for example in winter, the present process allows for the supply of hot water. According to the invention, the following steps are carried out: To determine, from among a plurality of tanks wholly buried in the ground, at least one tank filled with water, or partially filled with water, the temperature of whose contents is above a threshold temperature; to keep isolated at least one of said buried tanks, filled with water whose temperature is less than or equal to said threshold temperature, until the temperature of its contents rises above said threshold temperature; to ensure that water whose temperature is above said threshold temperature flows to at least one end-use point from said or at least one of said buried tanks thus determined, and said water is rainwater, drinking water, recycled wastewater, water from a watercourse such as a river, or a mixture of at least two of these waters

[0043] The present invention also relates to an installation for the supply of cold water, comprising: a plurality of tanks totally buried in the ground, each of said buried tanks being equipped with at least one first probe to measure the temperature of its contents, each of said first probes emitting temperature signals, and at least one second probe to measure the level of liquid contained in the corresponding tank, each of said second probes emitting level signals, at least one main supply line to supply water to at least some of the buried tanks, at least one water transport line connected to at least one end-use point, valves to isolate or connect said buried tanks with said lines, a control unit to receive temperature and liquid level signals from the buried tanks and to control said valves to isolate or connect said tanks with at least one of said lines,said management unit comprising a processor configured to implement the steps of a process for the supply of cold water as described above, based on said received signals.

[0044] In particular, this processor is configured to implement the following steps: determine, from among a plurality of tanks totally buried in the ground, at least one tank full of water, or partially filled with water, the temperature of whose contents is below a threshold temperature, keep isolated at least one of said buried tanks, filled with water whose temperature of contents is greater than or equal to said threshold temperature until the temperature of its contents falls below said threshold temperature, ensure that water whose temperature is less than said threshold temperature flows to at least one end-use point from said or at least one of said buried tanks thus determined, and said water is rainwater, drinking water, recycled wastewater, water from a watercourse such as a river, or a mixture of at least two of these waters.

[0045] Preferably, this installation includes at least one filtration element to filter the water conveyed to at least some of said underground reservoirs.

[0046] Advantageously, underground tanks are steel tanks or concrete tanks.

[0047] Advantageously, this installation includes at least one pump to pressurize said water for delivery to said point of final use.

[0048] To power this installation, for example for the operation of the management unit, it can be connected to a municipal electricity grid or to an independent power source. For illustrative purposes only, the latter could include one or more photovoltaic panels. Alternatively, or in addition, it could also include one or more wind turbines and / or one or more diesel generators.

[0049] According to one embodiment of this cold water supply system, the processor of said management unit is further configured to implement the step of supplying water to one or more empty tanks, or, when the temperature of their contents exceeds said threshold temperature, to one or more partially filled tanks, from among said plurality of underground tanks. Preferably, said threshold temperature is equal to 14°C, even more preferably equal to 12°C, and even more preferably equal to 10°C.

[0050] According to another embodiment of this cold water supply installation, the processor of said management unit is further configured to implement the additional step of supplying said at least one end-use point with water from at least one first underground tank, and detecting that the water level in said or at least one of said first tanks falls below a low threshold level, isolating said or said first tanks and replacing said or said first tanks with as many second underground tanks whose contents temperature is below said threshold temperature, so as to continue supplying said at least one end-use point.

[0051] According to another embodiment of this cold water supply installation, said at least one main supply line is connected to one or more external water supply sources of at least one type selected from the group including rainwater, recycled wastewater, water from a watercourse such as a river.

[0052] According to yet another embodiment of this installation for the supply of cold water, the said threshold temperature is equal to 14°C, even better equal to 12°C and even more preferably equal to 10°C.

[0053] According to yet another embodiment of this installation for the supply of cold water, at least one of said main tanks is connected to an auxiliary tank to supply the latter with water, in order to extend the storage capacity of said installation.

[0054] In yet another embodiment of this cold water supply system, it includes a draining device for emptying the system when necessary. Such a draining device can be used to purge the cold water supply system before winter to prevent damage from freezing. For example, this device could be a drain valve located at the lowest point of the system.

[0055] The present invention also relates to a cooling installation comprising an installation for the supply of cold water as described above and a floor and / or wall air conditioning device connected to said installation for its cold water supply, or a device for cooling or humidifying the outside air connected to said installation for its cold water supply.

[0056] According to a particular embodiment of this cooling system, the device for cooling the outside air includes at least one ground cooling circuit buried beneath a surface for pedestrian traffic, such as the external surface of a platform or sidewalk. For illustrative purposes only, each buried cooling circuit comprises a serpentine loop or a spiral loop.

[0057] Preferably, the pipe(s) supplying at least one underfloor cooling circuit and the underfloor cooling circuit itself are embedded in a concrete slab, which is covered with an exterior cladding made of a material having a thermal conductivity greater than or equal to 2 Wm⁻¹·K⁻¹, with an insulating layer interposed between the concrete slab and the foundations or the natural ground. Preferably, this insulating layer is made of a material having a thermal conductivity (denoted lambda) less than 0.06 Wm⁻¹·K⁻¹, and preferably less than or equal to 0.04 Wm⁻¹·K⁻¹. Advantageously, this insulating layer may include one or more reflective elements to reflect the thermal radiation generated by the slab incorporating the cooling circuit.

[0058] The present invention also relates to the use of a cooling installation as described above to cool a pedestrian surface such as a sidewalk, a quay or a square.

[0059] The present invention further relates to a building comprising a cooling installation as described above, for cooling a floor and / or a wall of at least one room of said building. Description of the drawings

[0060] Other advantages, purposes, and special features of the present invention will become apparent from the following description, given for explanatory purposes only and not as a limitation, with reference to the accompanying drawings, in which: Fig. 1 [ Fig. 1 ] is a schematic representation of a cold water supply installation according to a particular embodiment of the present invention; Fig. 2 [ Fig. 2] is a partial and cross-sectional view of a cooling installation according to a particular embodiment of the present invention, showing the arrangement of layers in which a floor cooling circuit is positioned, this arrangement defining a pedestrian traffic lane; Description of a method of implementation

[0061] The drawings and description below contain, for the most part, elements of a definite nature. They can therefore not only serve to better explain the present invention, but also contribute to its definition, if necessary.

[0062] Firstly, it should be noted that the figures are not to scale.

[0063] There Figure 1 illustrates schematically and partially a cold water supply installation according to a particular embodiment of the present invention.

[0064] This cold water supply system 10 comprises a plurality of tanks 11 completely buried in the ground at a depth that can vary depending on the nature of the soil. For illustrative purposes, this depth is on the order of a few meters.

[0065] These 11 tanks are steel vessels to facilitate heat exchange between the ground and the liquid contained in the tank.

[0066] Each of these 11 buried tanks is equipped with a first probe (not shown) to measure the temperature of the liquid contained in that tank, this first probe emitting temperature signals.

[0067] Each tank 11 also includes a second high probe to measure the high level of liquid in the corresponding tank and a second low probe to measure the low level of liquid in that tank, each of these second probes emitting level signals.

[0068] Installation 10 also includes pumps (not shown) to supply water transport lines connected to end-use points from the buried water tanks 11.

[0069] Twelve main supply lines supply these reservoirs eleven with rainwater collected from external rainwater collection sites.

[0070] Valves allow these 11 buried reservoirs to be isolated or connected to these pipes by fluid.

[0071] Rainwater filtration elements 13 are also planned to filter rainwater conveyed to at least some of these underground reservoirs 11.

[0072] This installation 10 also includes a management unit (not shown) to receive temperature and liquid level signals from the buried tanks 11 and to control said valves in order to isolate or connect the corresponding tanks with at least one of the water transport and rainwater supply lines.

[0073] This management unit includes a processor configured to implement the steps of a process for supplying cold water based on the received signals, the steps of this process being: determine, from among a plurality of tanks totally buried in the ground, at least one tank full of water, or partially filled with water, the temperature of whose contents is below a threshold temperature, keep isolated at least one of said buried tanks, filled with water whose temperature of contents is greater than or equal to said threshold temperature until the temperature of its contents falls below said threshold temperature, ensure that water whose temperature is less than said threshold temperature flows to at least one point of final use from said or at least one of said buried tanks thus determined.

[0074] Preferably, this threshold temperature is equal to 12°C.

[0075] This processor is also configured to perform an additional step whereby, supplying said at least one end-use point with water from at least one first buried tank, and detecting that the water level in said or at least one of said first tanks falls below a low threshold level, said or said first tank(s) are isolated and said or said first tank(s) are replaced by as many second buried tanks whose contents temperature is below said threshold temperature, so as to continue supplying said at least one end-use point.

[0076] There Figure 2 is a partial and cross-sectional view of a cooling installation according to a particular embodiment of the present invention, showing the arrangement of layers in which a floor cooling circuit 22 is positioned, this arrangement defining a pedestrian traffic lane.

[0077] This ground cooling circuit 22 is connected to a cold water supply installation as described above and consists of a serpentine loop integrated into the roadway.

[0078] The pedestrian walkway first includes an insulating layer 20 forming a thermal barrier with the foundations 21 or the natural ground supporting this walkway in order to prevent the cold from descending into the ground.

[0079] This insulating layer 20 is here made of a material having a thermal conductivity (denoted lambda) less than or equal to 0.04 Wm 1< .K -1< .

[0080] This could be a natural insulation material such as hemp fibers, natural expanded cork, or flax. It could also be a mineral insulation material such as rock wool or glass wool. Alternatively, it could be a synthetic insulation material, for example, made from polyurethane or polyester fibers, such as those obtained from recycled plastic bottles. Depending on the requirements, combinations of these insulation materials are possible.

[0081] The cooling circuit is embedded in a concrete slab 23 to hold it in position. This slab can be poured directly onto the insulating layer 20 after the pipes and the floor cooling circuit 22 have been installed. For illustrative purposes only, it has a thickness of between seven (7) cm and twenty (20) cm.

[0082] An exterior coating 24 is applied to this concrete slab 23, which forms a surface for pedestrian traffic. This exterior coating 24 is made of a material with low thermal conductivity.

[0083] For example, this exterior coating 24 can be made of granite (2.8 - 3.5 Wm -1< .K -1< ), reinforced concrete (2.3 - 2.5 Wm -1< .K -1< ), slate (2.1 - 2.2 Wm -1< .K -1< ) ​​or even a mixture of sand and gravel (2 Wm -1< .K -1< ).

[0084] The pipes will advantageously be made of a material having a thermal conductivity of less than 0.5 Wm -1< .K -1< such as PVC (polyvinyl chloride), PER (cross-linked polyethylene) or PB (polybutylene) while the floor cooling circuit 22 will preferably be made of galvanized steel.

[0085] Of course, this traffic lane may include one or more flexible protective layers, which may or may not be of the same material, sandwiched between two of its layers. For example, such a protective layer is a polyethylene film such as a polyane® film, a non-woven geotextile, or something similar.

[0086] For example, such a protective film could be placed between the insulating layer 20 and the concrete slab 23.

Claims

1. Method for supplying cold water or hot water, said method comprising the following steps: - determining, from a plurality of tanks (11) totally buried in the ground, at least one tank filled with water, or partially filled with water, of which the temperature of its contents is situated below a threshold temperature or above a threshold temperature, respectively, - keeping isolated at least one of said buried tanks (11) filled with water of which the temperature of its contents is greater than or equal to said threshold temperature until the temperature of its contents falls below or rises above said threshold temperature, respectively, - causing water of which the temperature is lower or higher than said threshold temperature, respectively, to flow to at least one end-use point from said or at least one of said buried tanks (11) thus determined, - this operation being carried out in a closed circuit, and - said water is rainwater, drinking water, recycled waste water, water from a watercourse such as a river, or a mixture of at least two of these waters.

2. Method according to claim 1, characterised in that the additional step of supplying water to one or more empty tanks (11) is carried out, or when the temperature of their contents is higher than said threshold temperature, one or more partially filled tanks (11), among said plurality of buried tanks (11).

3. Method according to claim 2, characterised in that said threshold temperature is equal to 14°C, more preferably equal to 12°C and even more preferably equal to 10°C.

4. Method according to any one of claims 1 to 3, characterised in that, feeding said at least one end-use point with water from at least one first buried tank, and detecting that the water level in said or at least one of said first tanks (11) falls below a low threshold level, said first tank(s) (11) is / are isolated and said first tank(s) (11) is / are replaced by as many second buried tanks (11) of which the temperature of their contents is lower than said threshold temperature, so as to continue feeding said at least one end-use point.

5. Method according to any one of the preceding claims, characterised in that the temperature of the water conveyed to said at least one end-use point is greater than a setpoint temperature, said water is cooled so that its temperature reaches said setpoint temperature before its use.

6. Method according to any one of the preceding claims, characterised in that said end-use point is a floor and / or wall-mounted air-conditioning device, or a device for cooling the outside air.

7. Method according to any one of the preceding claims, characterised in that the water supply of said at least one end-use point is controlled after analysis of several data measured locally by at least two sensors, possibly coupled with one or more weather data, and identification of a cooling need, said sensors being selected from the group comprising a temperature sensor, a humidity sensor, an anemometer and combinations of these elements.

8. Installation for the supply of cold or hot water, comprising: - a plurality of tanks (11) totally buried in the ground, - each of said buried tanks (11) being equipped with at least one first probe for measuring the temperature of its contents, each of said first probes emitting temperature signals, and at least one second probe for measuring the level of liquid contained in the corresponding tank, each of said second probes emitting level signals, - at least one main supply pipe (12) for supplying water to at least some of the underground tanks (11), - at least one water transport pipe connected to at least one end-use point, - valves for isolating or connecting these tanks (11) buried with said pipes, - a management unit for receiving temperature and liquid level signals from the buried tanks (11) and for controlling said valves in order to isolate or put in fluid communication said tanks (11) with at least one of said pipes, said installation operating in a closed circuit, - said management unit comprising a processor configured to implement the steps of the method for providing cold water or hot water according to claim 1 based on said received signals.

9. Installation according to claim 8, characterised in that the processor of said management unit is further configured to implement the steps of the method for providing cold water or hot water according to any one of claims 2 to 4.

10. Installation according to claim 8 or 9, characterised in that said at least one main supply pipe (12) is connected to one or more external water supply sources of at least one type chosen from the group comprising rainwater, recycled wastewater, water from a watercourse such as a river.

11. Installation according to any one of claims 8 to 10, characterised in that said threshold temperature is equal to 14°C, even more preferably equal to 12°C and even more preferably equal to 10°C.

12. Installation according to any one of claims 8 to 11, characterised in that at least one of said tanks (11) referred to as main is connected to an auxiliary tank to supply the tank with water in order to extend the storage capacity of said installation.

13. Cooling installation comprising an installation for supplying cold water according to any one of claims 8 to 12 and a floor and / or wall-mounted air-conditioning device connected to said installation for supplying it with cold water, or a device for cooling or humidifying the outside air connected to said installation for supplying it with cold water.

14. Cooling installation according to claim 13, characterised in that said device for cooling the outside air comprises at least one circuit for cooling the floor (22) placed under a covering for the movement of pedestrians, such as the outer surface of a platform or a pavement.

15. Cooling system according to claim 14, characterised in that the pipe(s) supplying said at least one circuit for cooling the floor (22) and said at least one circuit for cooling the floor (22) are coated in a concrete slab (23), which is covered with said outer coating (24) made of a material having a thermal conductivity greater than or equal to 2 W.m-1.K-1, an insulating layer (20) being interposed between said concrete slab (23) and the foundations (21) or the natural ground.

16. Building comprising a cooling installation according to claim 13 for cooling a floor and / or a wall of at least one room of said building.