HEATING APPLIANCE AND METHOD FOR INDUSTRIAL USE

Abstract

Industrial apparatus comprising: - a circuit (2) through which a working fluid circulates; said circuit (2) comprising a means (20) for heating the working fluid and being without an evaporator, - a circulation line (31) through which a heat transfer fluid circulates; the circulation line (31) being closed; the flow rate of the heat transfer fluid in said circulation line (31) being between 10 and 500 m³ / h, - a first heat exchanger (901); the first heat exchanger (901) putting said circuit (2) and said circulation line (31) into thermal communication, - an industrial heater (92) comprising a second heat exchanger (902) through which the circulation line (31) passes, characterized in that the heating means (20) consists of a piston pump (21). [FIG. 1]

Description

Title of the invention: HEATING APPARATUS AND METHOD FOR INDUSTRIAL USE

[0001] The present invention relates to an industrial apparatus and a heating method used in an industrial apparatus.

[0002] There are known heating devices for use in industrial installations, for example in pasteurization plants. In this case, the necessary heat 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 conventional elements of a reverse refrigeration cycle are used: a compressor acting on an at least partially gaseous fluid, a condenser, an evaporator and an expansion device.

[0003] In this context, the objective of the present invention is to provide a heating apparatus and a method for achieving high performance while optimizing energy consumption. Another objective is to enable easy maintenance. An additional objective is to provide a low-noise solution.

[0004] The specified objectives are substantially achieved by a heating apparatus and method described below.

[0005] According to a first aspect, the invention relates to an industrial apparatus comprising: - a circuit in which a working fluid circulates; said circuit comprising a means for heating the working fluid and being devoid of an evaporator, - a circulation line in which a heat transfer fluid circulates; the circulation line being closed on itself; the flow rate of the heat transfer fluid in said circulation line being between 10 and 500 m3 / h, - a first heat exchanger, the first heat exchanger placing said circuit and said circulation line in thermal communication, - an industrial heater comprising a second heat exchanger through which the circulation line passes.

[0006] The apparatus is characterized in that the heating means consists of a piston pump.

[0007] In other words, the circuit in which a working fluid circulates is devoid of an evaporator and the heating means consists solely of a piston pump for heating the working fluid circulating in said circuit. Consequently, the heating of the working fluid does not require air or liquid from the outside environment. This means that the heating of the device does not depend on the outside temperature.

[0008] According to another characteristic, said heat transfer fluid is other than water.

[0009] Advantageously, the first heat exchanger is a tube bundle exchanger.

[0010] In a preferred embodiment, the apparatus comprises capacity control means for controlling the flow rate of the working fluid in the circuit; said capacity control means comprising a motorized valve located along the circuit.

[0011] According to a first embodiment, the apparatus comprises a steam generator or a dryer; which in turn comprises said heater, which receives heat from the circulation line and uses it for a predetermined process.

[0012] According to a second embodiment, the apparatus comprises a distiller; or an emulsifier; or a pasteurizer which in turn comprises said heater, which receives heat from the circulation line and uses it for a predetermined process.

[0013] According to a third embodiment, the apparatus comprises a reactor for carrying out a chemical reaction; said reactor in turn comprises said heater, which receives heat from the circulation line and uses it for a predetermined process.

[0014] One of the main features of the invention is that the circuit comprises only a piston pump for heating the working fluid circulating inside.

[0015] Accordingly, the apparatus advantageously comprises an electric motor for driving the piston pump; said electric motor comprising / being a magnetic asynchronous electric motor.

[0016] In a preferred embodiment, the working fluid is selected from the group consisting of R1233ZD(E), R1234ZE and R295. Advantageously, the working fluid is R1233ZD(E) which has a global warming potential (GWP) of 5, i.e. a low greenhouse effect.

[0017] According to a specific embodiment, the apparatus comprises a control unit for regulating the temperatures and pressure necessary to maintain the working fluid circulating in the circuit in the liquid phase.

[0018] The invention also relates to a heating method involving the apparatus as described above, comprising the following steps: - circulating a working fluid in a circuit, - heating the working fluid which circulates in said circuit, - carrying out a heat transfer from the working fluid to a heat transfer fluid which recirculates in a first circulation line, - supplying the heat from the heat transfer fluid into a heater located along the circulation line.

[0019] Preferably, the working fluid has a pressure of between 6 and 8 bars and preferably always remains in the liquid phase in the circuit.

[0020] Other characteristics and advantages of the present invention emerge from the description given for information purposes, and therefore non-limiting, of a preferred but non-exclusive embodiment of a heating apparatus and method, illustrated schematically in [Fig.l].

[0021] In the attached figure, the industrial heating apparatus is designated by the reference number 1.

[0022] The apparatus 1 comprises a circuit 2 in which a working fluid circulates.

[0023] The working fluid may be an HFO fluid (hydrofluoroolefin-based fluid) such as, for example, R1366Mzz or R1233ZD or a fluid based on ammonia or inhibited calcium carbonate or others. It is advantageously R1233ZD(E).

[0024] In practice, the working fluid in circuit 2 always remains in the liquid phase and advantageously between 6 and 8 bars. In practice, the flow rate of the working fluid in circuit 2 is between 20 and 500 m3 / h (cubic meters / hour).

[0025] Circuit 2 comprises a means 20 for heating the working fluid. The heating means 20 will be better described below. Circuit 2 defines a heat pump.

[0026] The apparatus 1 comprises a line 31 for the circulation of a heat transfer fluid. The volumetric flow rate of the heat transfer fluid in said line 31 is advantageously greater than 10 m3 / h; it is preferably greater than 30 m3 / h. In practice, the volumetric flow rate of the heat transfer fluid is less than 500 m3 / h; it is advantageously less than 200 m3 / h, even more preferably less than 150 m3 / h. Preferably, the line 31 defines a loop closed on itself. It is therefore a recirculation line.

[0027] The apparatus 1 comprises a first heat exchange means 5 between the circuit 2 and the circulation line 31. The first heat exchange means 5 comprises a first heat exchanger 901. The first heat exchanger 901 places the circuit 2 and the line 31 in thermal communication. Consequently, the first exchanger 901 places the working fluid circulating in the circuit 2 in thermal communication with the heat transfer fluid circulating in the line 31. As illustrated in [Fig.l], the first exchanger 901 is a shell and tube exchanger. This solution is particularly advantageous, since in industrial applications it is important to have substantial flow rates. In an alternative solution, it could be a plate exchanger.

[0028] In practice, the heat transfer fluid in line 31 always remains in the liquid state. In practice, the heat transfer fluid is other than water. Advantageously, the fluid The heat transfer fluid is an HFO fluid (hydrofluoroolefin-based fluid) such as, for example, R1366Mzz or R1233ZD(E) or a fluid based on ammonia or inhibited calcium carbonate or others. It is advantageously R1233ZD(E).

[0029] In a particular embodiment, the working fluid in the first exchanger 901 undergoes a temperature variation of between 35 and 85°C. The working fluid cools in the first exchanger 901 and heats the heat transfer fluid which circulates in the line 31.

[0030] Conveniently, the apparatus 1 comprises capacity control means 93 for controlling the flow rate of the working fluid in the circuit 2. The capacity control means 93 comprise a motorized valve 930 located along the circuit 2. The motorized valve 930 is preferably remotely operated. For this purpose, it has a special electrical actuator (for example, there may be a motor or an electromagnet). The valve 930 may be actuated by an operator or by a pressure sensor along the circuit 2 to maintain the working fluid circulating in the circuit in the liquid phase.

[0031] In practice, the motorized valve 930 is located downstream of the first exchanger 901 and upstream of the heating means 20.

[0032] As illustrated in [Fig.l], the heating means 20, the motorized valve 930 and the first heat exchanger 901 are arranged in series along the circuit 2.

[0033] Along line 31, the apparatus 1 may comprise a recirculation pump for the heat transfer fluid. The water recirculation pump is typically a centrifugal pump. It allows the heat transfer fluid to be recirculated along line 31.

[0034] The heating means 20 is a piston pump 21. This is typically a high-pressure piston pump 21. The apparatus 1 can be considered a heat pump in the sense that it has a COP greater than 7, preferably greater than 10. The COP (Coefficient of Performance) is an index of the efficiency of a heat pump and is given by the ratio between the energy delivered and the electricity consumed. However, unlike a standard heat pump, the system of the invention does not include an evaporator.

[0035] The pump 21 thus causes the working fluid to heat. This occurs due to the compressive action on the incompressible working fluid. Such compression forces the working fluid along the conduits of the pump 21, causing an increase in kinetic energy and heating of the fluid by friction.

[0036] In practice, the circuit 2 comprises only said piston pump 21 for heating the working fluid circulating inside.

[0037] The piston pump 21 is a volumetric pump of known type, if considered in itself. 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.

[0038] Advantageously, the pump 21 comprises more than three pistons. The pumping chambers are conveniently integrated into a body which can be rotated. The rotation of this body and therefore of the pumping chambers drives the pistons into rotation and thus causes a reciprocating back and forth movement of the pistons in the corresponding pumping chambers. In fact, the pistons have one end pressed by elastic means against a plate inclined relative to the axis of rotation of the pumping chambers.

[0039] The apparatus 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 contributes to the quietness of the apparatus 1. Conveniently, the motor 22 comprises an inverter. The operation of the motor 22 is also regulated according to the feedback provided by the temperature sensor 321 located along the line 31.

[0040] The device 1 may comprise a filter 61 and a sight glass 62. In practice, they are arranged downstream of the first exchanger 901 and upstream of the piston pump 21.

[0041] The apparatus 1 conveniently comprises a soundproof housing housing the piston pump 21 therein.

[0042] The apparatus 1 also comprises a central control unit for controlling the overall operation and regulating the temperatures and pressure necessary to maintain the working fluid circulating in the circuit 2 in the liquid phase.

[0043] The apparatus 1 also comprises an industrial heater 92. The heater 92 comprises a second exchanger 902. The circulation line 31 passes through the second exchanger 902. The circulation line 31 thus transports the heat transfer fluid from the first to the second exchanger 901, 902 and allows its return from the second exchanger 902 to the first exchanger 901. This is done in a closed loop. The second exchanger 902 is therefore arranged along the circulation line 31. The heat transfer fluid is cooled in the second exchanger 902. The line 31 thus defines the hot side of the second exchanger 902. The cold side may be a conduit in which another fluid circulates or an environment in which the released heat triggers a process. The second heat exchanger 902 could thus release heat into an environment or transfer it to another fluid to be heated.Conveniently, the heat transfer fluid is a liquid and remains liquid throughout the path of line 31.

[0044] The heat transfer fluid thus transports to the heater 92 at least part of the heat generated in the circuit 2 by the pump 21 and will then be used by the industrial device 1.

[0045] The apparatus 1 may in fact comprise, by way of non-exhaustive example, one of the following devices: - a steam generator, or - a dryer; or - a distiller; or - an emulsifier; or - a pasteurizer; or - a reactor for carrying out a chemical reaction.

[0046] The device in question in turn comprises the heater 92 in order to receive the heat from the circulation line 31. The heat thus obtained is used to carry out the dedicated processes of each device. The device can therefore be defined as an industrial heat treatment device.

[0047] The present invention also relates to a heating method used in an industrial apparatus.

[0048] The method is advantageously implemented by an apparatus 1 having one or more of the characteristics described above.

[0049] The method comprises the following steps: - circulate a working fluid in a circuit 2; in practice, the working fluid always remains liquid while recirculating inside circuit 2 (we could thus speak of operating liquid); - heat the working fluid circulating in circuit 2.

[0050] The step of heating the working fluid circulating in the circuit 2 takes place during the passage of the working fluid in a piston pump 21 located along the circuit 2.

[0051] The piston pump 21 thus heats the working fluid. In practice, at least at the pump 21 (but preferably everywhere), the working fluid is liquid. The piston pump 21 acts on said working fluid, causing an increase in pressure of between 11 and 50 bar, between 6 and 8 bar for example when R1233ZD(E) is used, and / or a rise in temperature of at least 100°C. Downstream of the piston pump 21, temperatures for the working fluid even higher than 110°C or 165°C can be obtained. In addition to causing the heating of the working fluid, the pump 21 is also solely responsible for its movement.

[0052] The method comprises a step of transmitting heat from the working fluid to a heat transfer fluid which recirculates in a first circulation line 31. This is done by means of a first exchanger 901.

[0053] Conveniently, the method comprises the step of providing heat from the heat transfer fluid into a heater 92 located along the circulation line 31. The heater 92 uses this heat to perform specific operations. The heater 92 actually includes a second heat exchanger. For example, the heater 92 could be integrated into a steam generator. In this case, the heat transported by the heat transfer fluid through the second exchanger 902 is used to produce steam.

[0054] Or the heater could be a dryer and the heat is used to dry food (or non-food) products present in an environment.

[0055] Or, in the case of a distiller, heat could be used to promote state transitions and separate chemical components.

[0056] Or, in the case of a pasteurizer, heat could be used to treat fresh raw materials and semi-processed products, at a temperature such that it significantly reduces the bacterial load, while preserving the nutritional properties of the food.

[0057] The present invention has significant advantages.

[0058] First of all, it allows for remarkable heating performance. In addition, it makes maintenance easier.

[0059] It is also possible to obtain a compact and low-noise solution.

[0060] The invention as conceived is susceptible to numerous modifications and variations, all falling within the inventive concept which characterizes it. Furthermore, all the features can be replaced by other technically equivalent elements. In practice, all the materials used, as well as the dimensions, can be any, according to the needs.

Claims

Claims

1. Industrial apparatus comprising: - a circuit (2) in which a working fluid circulates; said circuit (2) comprising means (20) for heating the working fluid and being devoid of an evaporator, - a circulation line (31) in which a heat transfer fluid circulates; the circulation line (31) being closed on itself; the flow rate of the heat transfer fluid in said circulation line (31) being between 10 and 500 m3 / h, - a first heat exchanger (901); the first heat exchanger (901) putting said circuit (2) and said circulation line (31) in thermal communication, - an industrial heater (92) comprising a second heat exchanger (902) in which the circulation line (31) passes, characterized in that the heating means (20) consists of a piston pump (21).

2. Apparatus according to claim 1, characterized in that said heat transfer fluid is other than water.

3. Apparatus according to claim 1 or 2, characterized in that said first heat exchanger (901) is a tube bundle exchanger.

4. Apparatus according to any one of the preceding claims, characterized in that it comprises capacity control means (93) for controlling the flow rate of the working fluid in the circuit (2); said capacity control means (93) comprising a motorized valve (930) located along the circuit (2).

5. Apparatus according to any one of the preceding claims, characterized in that it comprises a steam generator; or a dryer; which in turn comprises said heater (92), which receives heat from the circulation line (31) and uses it for a predetermined process.

6. Apparatus according to any one of claims 1 to 4, characterized in that it comprises a distiller; or an emulsifier; or a pasteurizer which in turn comprises said heater (92), which receives heat from the circulation line (31) and uses it for a predetermined process.

7. Apparatus according to any one of claims 1 to 4, characterized in that it comprises a reactor for carrying out a chemical reaction; said reactor in turn comprises said heater (92), which receives heat from the circulation line (31) and uses it for a predetermined process.

8. Apparatus according to any one of the preceding claims, characterized in that it comprises an electric motor (22) for driving the piston pump (21); said electric motor (22) comprising / being a magnetic asynchronous electric motor (22).

9. Apparatus according to any one of the preceding claims, characterized in that the working fluid is R1233ZD(E).

10. Apparatus according to any one of the preceding claims, characterized in that it comprises a control unit for regulating the temperatures and pressure necessary to maintain the working fluid circulating in the circuit (2) in the liquid phase.

11. A heating method involving the apparatus according to any one of claims 1 to 10, comprising the following steps: - circulating a working fluid in a circuit (2); - heating the working fluid which circulates in said circuit (2); - effecting a heat transmission from the working fluid to a heat transfer fluid which recirculates in a first circulation line (31), - supplying the heat from the heat transfer fluid into a heater (92) located along the circulation line (31).

12. Method according to claim 11, characterized in that the working fluid has a pressure of between 6 and 8 bars.

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