Patent Application
20250164119
This application claims the benefit of priority from Italian Patent Application No. 10 2023 000022170 filed on Oct. 23, 2023, the entirety of which is incorporated by reference.
The present invention relates to a system and a method for heating hot water to be used for both heating at least one environment of a building and for the sanitary water to be used in a building.
It is therefore a water heating system for civil use.
Building heating systems are known. In this case the hot water to be sent to the convector heaters and the hot water to be used as sanitary water can be obtained by means of a boiler which burns a fuel. In an alternative solution, a heat pump can be used in which the classic elements of a reverse refrigeration cycle are used: compressor acting on an at least partially gaseous fluid, condenser, evaporator, throttling member. The COP (Coefficient of Performance) of a heat pump of this type is usually less than 7. The COP is an efficiency index of a heat pump and is given by the ratio between the energy delivered (e.g., heat transferred to the environment to be heated) and the electrical energy consumed.
In this context, the technical task underlying the present invention is to propose a system and a heating method which allow to obtain high performance, while simultaneously optimising energy consumption. A further object is to allow easy maintenance. An additional object is to provide a noiseless solution.
The defined technical task and the specified aims are substantially achieved by a system and a heating method described below.
According to a first aspect, the invention concerns a system for heating water comprising:
The system is characterized in that the heating means consists in a piston pump.
In other words, the circuit in which an operating fluid circulates is deprived of evaporator and the heating means only consist in piston pump for heating the operating fluid circulating in the said circuit. As a consequence, the heating of the operating fluid does not require air or liquid from external environment. This means that the heating of the system does not depend on the exterior or outside temperature.
According to another feature, the circuit comprises an electric motor for driving the piston pump, said electric motor comprising/being an asynchronous magnetic electric motor.
In a preferred embodiment, the operating fluid is chosen in the group consisting of R1233ZD(E), R1234ZE and R295.
Advantageously, the operating fluid is R1233ZD(E) which has a Global warming potential (GWP) of 5, ie a low green house effect.
According to a specific embodiment, the first heat exchange means comprises:
Advantageously, the said first supply line of water for sanitary use comprises a coil which transits inside the tank.
In that embodiment, the system advantageously comprises an additional heat exchanger for exchanging heat between the circuit and the first supply line.
Preferably, the system comprises a throttling valve interposed between said first heat exchanger and said additional heat exchanger.
The invention also concerns a method for heating water involving the system previously disclosed.
The method comprises the following steps:
Advantageously, the operating fluid has a pressure between 6 and 8 bar and preferably always remains in the liquid phase in the circuit.
Further features and advantages of the present invention will become more apparent from the indicative and thus non-limiting description of a preferred but not exclusive embodiment of a system and a heating method, as schematically illustrated in
In the appended figures of the drawings, reference number 1 denotes a system for heating water.
The system 1 comprises a circuit 2 in which an operating fluid circulates.
The operating fluid can be an HFO (hydrofluoroolefin-based fluid) fluid such as R1366Mzz or R1233 ZD, or based on ammonia or inhibited calcium carbonate or still others. It is advantageously R1233ZD(E).
Suitably, the operating fluid in the circuit 2 always remains in the liquid phase and advantageously between 6 and 8 bar.
The circuit 2 comprises a means 20 for heating the operating fluid.
The circuit 2 comprises a first line 31 for supplying water for sanitary purposes. The first supply line 31 typically receives mains water in input (typically at 3 bar and 15° C.). Such an input is at reference 310.
The system 1 comprises a second line 32 for supplying heating water of at least one environment of a building. This is water intended for transit in elements adapted to diffuse heat in an environment of the building (for example convector heaters 7). The second supply line 32 is closed on itself and therefore defines a recirculation line. The first and the second line 31, 32 are separate and distinct.
The numerical adjectives “first” and “second” are used previously only to distinguish between the supply lines, they do not indicate an order or a priority (the same applies to the rest of the text).
The system 1 comprises first heat exchange means 5 for exchanging heat between the circuit 2 and the first supply line 31.
The first heat exchange means 5 comprises a path 50 closed on itself in which a heat transfer fluid circulates (the closed path 50 is therefore a circuit). Such a heat transfer fluid in the path 50 always remains in the liquid state.
The first heat exchange means 5 comprises a first heat exchanger 52 which puts the operating fluid circulating in the circuit 2 and the heat transfer fluid circulating in said path 50 in thermal communication. In a particular operating mode, the operating fluid enters the first exchanger 52 at a temperature comprised between 110° C. and 130° C. and exits at a temperature comprised between 30° C. and 50° C. The heat transfer fluid circulating in the path 50 in such an operating mode exits from the first exchanger 52 at a temperature above 80° C. (for example comprised between 80° and 90° C.).
The first heat exchange means 5 comprises a heat exchange tank 53 in thermal communication with said first supply line 31. For example, such a tank 53 has a capacity comprised between 10 and 30 litres, typically 15 litres. The tank 53 also comprises an expansion vessel 530. Suitably, the system 1 comprises a pump 501 (typically centrifugal) for recirculating the heat transfer fluid in the path 50. The pump 501 is located downstream of the first exchanger 52 and upstream of the tank 53.
In particular, the first line 31 for supplying water for sanitary use comprises a coil 311 which transits inside the tank 53. The heat transfer fluid is present in the tank 53 and externally laps the coil 311. Suitably, in the operating mode described above, the sanitary water in output from the tank 53 is at a temperature comprised between 55° C. and 65° C. Suitably, there is a temperature probe 531 at the tank 53, which measures the temperature of the heat transfer fluid.
Advantageously, system comprises an additional heat exchanger 54 in which said operating fluid and said water for sanitary use transit. Suitably, the additional heat exchanger 54 carries out the function of pre-heater of the sanitary water (before the same enters the tank 53 or rather the coil 311 present in the tank 53). The exchanger 54 is located upstream of the tank 53 along the flow direction of the sanitary water. The first exchanger 52 and the additional exchanger 54 are mutually spaced apart.
Suitably, the circuit 2 comprises a throttling valve 23 interposed between said heat exchanger 52 and said additional heat exchanger 54. The throttling valve 23 is located in input to the additional heat exchanger 54. Suitably, the throttling valve 23 can receive a control input as a function of the pressure downstream of the additional heat exchanger 54.
As exemplified in
The system 1 comprises second heat exchange means 4 between the circuit 2 and the second supply line 32. The second heat exchange means 4 comprises/is for example a second heat exchanger 55, typically a plate exchanger. They define an area in which the circuit 2 and the second supply line 32 are in thermal contact. The second exchanger 55 therefore affects both the circuit 2 and the second supply line 32. For example, the operating fluid could enter the second heat exchange means 4 at a temperature comprised between 15° and 130° C. and exit therefrom at a temperature comprised between 130° C. and 110° C. Suitably, the heating water of at least one environment of a building exits from the exchanger at a temperature comprised between 8° and 90° C.
Suitably the operating fluid and the heating water of at least one environment of a building are in counter-current in the second heat exchange means 4.
A temperature probe 321 is placed along the second line 32.
The system 1 comprises a water recirculation pump 322 along the second line 32. The water recirculation pump 322 is typically a centrifugal pump. It allows water to be recirculated along the second line between the second heat exchange means and the convector heaters 7.
The heating means 20 is a piston pump 21. Typically, it is a high-pressure piston pump 21. The system 1 can be considered a heat pump in that sense that it has a COP greater than 7, preferably greater than 10. The COP (Coefficient of Performance) is an efficiency index of a heat pump and is given by the ratio between energy delivered and electrical energy consumed. Nevertheless, contrary to a standard heating pump, the system of the invention does not comprise evaporator.
The pump 21 thus causes a heating of the operating fluid. This occurs due to the compression action on the incompressible operating fluid. Such compression forces the operating fluid along the ducts of the pump 21, causing an increase in the kinetic energy and a heating thereof by friction.
Suitably, the circuit 2 comprises only said piston pump 21 for heating the operating fluid circulating therein.
The piston pump 21 is a positive displacement pump of known type, if considered in its own right. The piston pump could be an axial piston pump, but also a piston pump of another type. For example, it includes pistons housed in corresponding pumping chambers. The pumping chambers are conveniently integrated into a body that can be rotated. The rotation of this body and therefore of the pumping chambers causes the pistons to rotate and therefore determines an alternating back and forth motion of the pistons in the corresponding pumping chambers. In fact, the pistons have one end pressed by elastic means against a plate inclined with respect to the rotation axis of the pumping chambers.
The system 1 comprises an electric motor 22 for driving the piston pump 21. The electric motor 22 preferably comprises/is a magnetic asynchronous electric motor 22. This facilitates the noiselessness of the system 1. Suitably, the motor 22 comprises an inverter. The operation of the motor 22 is also regulated as a function of the feedback provided by the temperature probes 321 placed along the second line 32.
The additional exchanger 54 is interposed between the first exchanger 52 and the piston pump 21.
The system 1 can comprise a filter 61, an inspection hole 62, a liquid receiver 63. Suitably they are arranged downstream of the first exchanger 52 and upstream of the additional heat exchanger 54.
The system 1 suitably comprises a soundproofed casing housing the piston pump 21 therein.
The system 1 also comprises a control unit for controlling the overall operation and regulation of the required temperatures and pressure required to keep in a liquid phase the operating fluid circulating in circuit 2.
An object of the present invention is also a method for heating water.
The method is advantageously implemented by a system 1 having one or more of the features described above.
The method comprises the following steps:
The step of heating the operating fluid transiting in the circuit 2 occurs in the transit of the operating fluid in a piston pump 21 placed along the circuit 2. Therefore, the piston pump 21 heats the operating fluid. Suitably at least at the pump 21 (but preferably everywhere), the operating fluid is liquid. The piston pump 21 acts on said operating fluid so that the pressure of the operating fluid is between 6 to 8 bar for example when R1233ZD(E) is used. In some embodiment, the piston pump 21 acts on said operating fluid, causing a pressure increase at least 10 bar and/or a temperature increase by at least 90° C. Downstream of the piston pump 21, temperatures for the operating fluid can be obtained which are even higher than 110° C. or 120° C. The pump 21, in addition to causing the heating of the operating fluid, is also solely responsible for its movement.
The method comprises the step of performing a transmission of heat from the operating fluid present in the circuit 2 to water for sanitary use. Typically, a flow rate comprised between 12 and 16 litres/minute is envisaged. The water for sanitary use moves along a first supply line 31. Such a transmission of heat from the operating fluid present in the circuit 2 to the water for sanitary use occurs indirectly. In fact, it envisages a transfer of heat between the operating fluid circulating in the circuit 2 and the heat transfer fluid circulating in a closed path 50 and the transfer of heat from the heat transfer fluid circulating in the closed path 50 to water for sanitary use in transit along the first line 31. The heat transfer from the circulating heat transfer fluid in the closed path 50 to the water for sanitary use in transit along the first line 31 occurs in a heat exchanger preferably comprising:
Typically, such a section defines a coil 311. Suitably the coil 311 is embedded in the heat transfer fluid present in the tank 53. The heat transfer fluid is liquid. For example, it can be of the same type as the operating fluid.
The first line 31 is a path which winds between a mains water introduction zone up to one or more taps which make the water available to the user (typically in the form of running water).
The method also comprises the step of performing a transmission of heat from the operating fluid present in the circuit 2 to water for heating at least one environment of a building. This occurs for example by second heat exchange means 4. Typically, the second heat exchange means 4 comprises a plate exchanger.
The water for heating moves along a second supply line 32. In particular, the side line 32 recirculates on itself. Therefore, the water for heating receives the heat, reaches the convector heater(s) 7 to heat at least one environment of the building and then goes back to be heated again.
The present invention achieves important advantages.
Firstly, it allows to obtain considerable heating performance perfectly compatible with that related to the heating of at least one part of a building and to the heating of sanitary water. Furthermore, it allows to facilitate maintenance. It is also possible to obtain a compact and noiseless solution.
The invention as it is conceived is susceptible to numerous modifications and variants, all falling within the scope of the inventive concept characterised thereby. Further, all the details can be replaced with other technically equivalent elements. In practice, all the materials used, as well as the dimensions, can be any whatsoever, according to need.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102023000022170 | Oct 2023 | IT | national |
