Heat transfer method and device

Abstract

Heat transfer methods, comprising the steps: - Separation (S1) of a working medium into a liquid propellant fluid (TF) and a gaseous suction fluid (SF) by means of at least one first phase separator (20), - Increase (S2) of the pressure in the propellant fluid (TF) by means of at least one pump element (30), - Heating (S3) of the motive fluid (TF) without phase transition in at least one heat exchanger (40), - Suction (S4) of the suction fluid (SF) with the aid of the propellant fluid (TF) and generation of a two-phase mixed fluid (MF) from the suction fluid (SF) and the propellant fluid (TF) in at least one ejector (50), - Separation (S5) of the mixed fluid (MF) into a liquid subsidiary fluid (NB) and a gaseous utility fluid (NU) by means of at least one further phase separator (60), - Return (S6) of the bypass fluid (NB) from the further phase separator (60) to the at least one first phase separator (20) via at least one throttling element (70), - Providing (S8) the utility fluid (NU) for heat transfer.

Description

[0001] The invention relates to a method for heat transfer and a corresponding device.

[0002] The thermodynamic utilization of waste heat or ambient heat, e.g., in industrial plants, offers great potential for making heat consumers, such as energy-intensive production processes or building heating, more efficient. In particular, the operating principle of the heat pump offers the possibility of transporting waste heat or ambient heat from a heat source to a heat sink, where the heat sink can have a higher temperature than the heat source. The thermal energy is transported by a flowing working fluid, also called a refrigerant. Typically, the working fluid is heated by the heat source and then evaporated and compressed for transport to the heat sink, for example, to minimize energy losses during transport. This has typically been achieved through direct evaporation in a heat exchanger or...by pumping the liquid medium to a higher pressure and subsequently reducing it using a throttle valve, so that at least part of the liquid working medium evaporates.

[0003] The use of ejectors to increase the mean pressure between two vaporous media is also known. For example, CN 109630224 B describes waste heat recovery and power generation using an ejector.

[0004] Currently, known heat transfer methods and devices require that the components used, especially the heat exchanger, are designed for the evaporation of the working medium. This negatively impacts the dimensioning of the components used, particularly the heat exchanger. Furthermore, the known methods and devices are energy-inefficient or have a low efficiency, which in turn hinders the economical integration of this technology into existing or new industrial processes.

[0005] From DE 37 35 386 A1, a cooling system with a waste heat-driven pump is known, comprising a boiler in which a working fluid can be heated to its evaporation temperature. A jet pump is also provided, which is connected to the boiler and receives the steam generated in the boiler at high pressure and temperature, creating a low-pressure zone. A main condenser is in flow connection with the jet pump to condense the outflowing fluid from the jet pump. A separating device is also provided, connected to the main condenser, to separate the liquefied outflowing fluid into a first coolant with a first saturation temperature and a second coolant with a second saturation temperature higher than the first saturation temperature. A pump pumps the second liquid coolant to the boiler, with a first auxiliary condenser receiving and condensing the first coolant in vapor form.Furthermore, an evaporator is provided, which is connected between the auxiliary condenser and the vacuum zone of the jet pump. An expansion valve controls the amount of the first refrigerant that is introduced into the evaporator.

[0006] US Patent 4,625,522 A discloses a method for generating cold and / or heat using a non-azeotropic liquid mixture in a closed loop with an ejector. In this process, a working fluid is condensed and separated into two fractions, the first fraction evaporating at a relatively low temperature and the second fraction evaporating at a relatively high temperature. The two evaporated fractions then pass through an ejector and are returned to the condenser.

[0007] From CN 1 08 413 637 A, an industrial flue gas waste heat recycling and dehumidification system is known, comprising a heater, an evaporator, a working fluid pump, an ejector, a cooler, a throttle valve, and a gas and liquid separator. The system uses the flue gas waste heat as the system drive heat source. In a circulation process, the heat exchange between the flue gas, the heater, and the evaporator enables comprehensive utilization of the flue gas waste heat and the recycling of water vapor in the flue gas.

[0008] A method for cooling by boosting and expansion evaporation is known from CN 1 249 418 A.

[0009] The technical problem is to create a process and a device that offer increased efficiency in heat transfer while simultaneously reducing the requirements for the dimensioning of the components.

[0010] The solution to the technical problem is provided by the articles with the features of the independent claims. Further advantageous embodiments of the invention are described in the dependent claims.

[0011] Therefore, a heat transfer method is proposed, comprising the following steps: - Separation of a working medium into a liquid propellant fluid and a gaseous suction fluid by means of at least one first phase separator, - Increasing the pressure in the propellant fluid by means of at least one pump element, - Heating the motive fluid without phase transition in at least one heat exchanger, - Suction of the suction fluid with the aid of the propellant fluid and generation of a two-phase mixed fluid from the suction fluid and the propellant fluid in at least one ejector, - Separation of the mixed fluid into a liquid secondary fluid and a gaseous primary fluid by means of at least one further phase separator, - Returning the by-flow fluid from the further phase separator to the at least one first phase separator via at least one throttling element, - Providing the working fluid for heat transfer.

[0012] The working medium is a fluid that, through changes of state, is suitable for transporting thermal energy and thus for heat transfer. The working medium can therefore be described by state variables such as pressure, temperature, enthalpy, and entropy, or by its state of matter. In particular, the working medium can assume different states of matter or phases and can exist in at least liquid, gaseous, or two-phase form. The change of a state variable or state of matter can be brought about by one or more of the aforementioned process steps. Water, ammonia, carbon dioxide, or hydrocarbons are particularly suitable as working media.

[0013] To better distinguish the process steps, the working fluid may be referred to by different names. Specifically, it may be called propellant fluid, suction fluid, mixing fluid, auxiliary fluid, and working fluid. The respective name is determined by the working fluid's current use in the corresponding process step.

[0014] The first and / or subsequent phase separators are preferably designed as settling tanks. The working medium can be present in two phases, i.e., gaseous and liquid, within each phase separator. Furthermore, the working medium is separated into a liquid fluid and a gaseous fluid within the respective phase separator. In this process, a portion of the working medium present in liquid form in the first phase separator is separated from the portion present in gaseous form. In a settling tank, this separation occurs, for example, under the influence of gravity, with the liquid portion settling at the bottom of the phase separator, for example, due to its higher density compared to the gaseous portion, while the gaseous portion rises above the liquid portion.

[0015] By separating the components or fluids according to their state of matter, the different states of matter of the fluids can be advantageously utilized in the further course of the process according to the invention. In the at least one first phase separator, the separation of the working medium into a liquid motive fluid and a gaseous suction fluid enables only the liquid component of the working medium to be supplied to the at least one heat exchanger, thereby increasing the heat transfer capacity of the working medium in the heat exchanger. The gaseous component, on the other hand, is available as suction fluid for further processing.

[0016] Preferably, the first and / or subsequent phase separators are designed as vertical phase separators. This allows the footprint of the phase separator to be reduced while maintaining the same volume. In other words, the phase separator is preferably arranged upright or vertically, so that, for example, the cross-sectional area of ​​the phase separator facing the ground is smaller than the cross-sectional area of ​​the phase separator arranged perpendicular to it. This has a beneficial effect on the footprint of the phase separator.

[0017] The pump element can be designed, for example, as an axial or radial pump. The pump element is preferably electrically driven. The pump element primarily increases the pressure of the motive fluid. This ensures that the pressure of the motive fluid is sufficient to prevent a phase transition, particularly evaporation of the motive fluid, during heating in the at least one heat exchanger.

[0018] The heating of the motive fluid, which passes through at least one heat exchanger, takes place—as already explained—without a phase transition. In other words, the motive fluid remains liquid during heating and does not change its state of matter. Heating specifically refers to the introduction of thermal energy into the motive fluid.

[0019] The heat exchanger can be designed, for example, as a recuperator or a shell-and-tube heat exchanger. To heat the motive fluid, the heat exchanger can be surrounded by an ambient fluid that, upon contact with the heat exchanger, has a higher temperature than the motive fluid. Due to the temperature difference between the motive fluid and the surroundings, thermal energy can be transferred to the motive fluid.

[0020] Because the heating of the motive fluid occurs without a phase transition, the heat exchanger can be made smaller. For example, it is not necessary to include a steam space as part of the heat exchanger. This advantageously reduces the space required for the at least one heat exchanger and thus the costs of implementing the process. Furthermore, the process according to the invention makes it possible to access heat sources that were previously unusable due to space limitations.

[0021] The ejector is a fluid-mechanical component and can, for example, be designed as a jet pump. In particular, the ejector can consist of several fluidically interconnected sections. For example, the ejector can have a drive section for accelerating the motive fluid, a suction section for drawing in the suction fluid, a mixing section for generating a mixed fluid, and an expansion section for increasing the pressure of the mixed fluid. Furthermore, the ejector is fluidically connected to at least one first phase separator. In other words, the ejector utilizes the energy introduced into the motive fluid by means of the pump element or the heat exchanger to draw in and compress the suction fluid through fluid-mechanical effects, especially the Bernoulli effect, thus increasing the pressure without requiring an additional drive, such as an electric drive.This advantageously increases the energy efficiency of the process. Furthermore, the ejector offers the advantage of requiring very little maintenance, especially compared to, for example, an electrically driven compressor, particularly since no moving parts are necessary for its operation.

[0022] The drive section can be designed, for example, as a nozzle. In the drive section, the high-pressure motive fluid coming from the heat exchanger is accelerated. This causes the pressure in the motive fluid to drop. In particular, the pressure in the motive fluid falls below the pressure of the suction fluid.

[0023] Because the propellant fluid is liquid upon entering the ejector, the ejector, and in particular the propellant section, can be dimensioned correspondingly smaller compared to the use of vaporous fluids. This has a beneficial effect on the installation space requirements and the costs of the method according to the invention.

[0024] From the propellant zone, the accelerated propellant fluid can enter the mixing zone, where the propellant fluid can at least partially evaporate due to the reduced pressure.

[0025] The suction area can, for example, be designed as an annular nozzle and arranged around the drive area, and fluidically connected to the mixing area. The pressure difference generated between the suction area and the mixing area – by means of the accelerated drive fluid – allows the suction fluid to be drawn from the suction area into the mixing area.

[0026] The mixing section can be designed, for example, as a mixing tube. In the mixing section, the suction fluid can be mixed with the propellant fluid, creating a two-phase mixing fluid. From the mixing section, the mixing fluid can enter the expansion section.

[0027] The expansion zone can, for example, be designed as a diffuser. The pressure of the mixing fluid can be increased within the expansion zone.

[0028] In at least one further phase separator, the mixed fluid is separated into the liquid by-fluid and the gaseous useful fluid. This separation of the mixed fluid into the liquid by-fluid and the gaseous useful fluid in the at least one further phase separator also ensures that only the high-energy component of the mixed fluid, or the component of the mixed fluid with a high enthalpy, is provided for heat transfer in the form of the gaseous useful fluid. The liquid by-fluid, on the other hand, is returned from the further phase separator to the at least one first phase separator via the at least one throttling element.

[0029] The throttling element can be designed, for example, as a throttle valve or a perforated disc. The throttling element ensures that an operating pressure differential is maintained between the at least one first phase separator and the at least one further phase separator. Simultaneously, the recirculation of the by-product fluid increases the mass flow rate through the at least one further phase separator. This allows more of the mixed fluid to flow into the further phase separator, which has a beneficial effect on the supply of the useful fluid. Furthermore, the throttling element expands the by-product fluid, allowing it to at least partially evaporate. In particular, the by-product fluid enters the at least one first phase separator in two-phase form.

[0030] The supply of the heat transfer fluid can be achieved, for example, via pipelines. For instance, the heat transfer fluid can be fed from at least one further phase separator into a pipe system of a steam heating system. In particular, it is possible that the heat transfer fluid, after supply, is part of an open circuit, or that, after supply by the method according to the invention, the heat transfer fluid flows into an open circuit and is not reused as part of the working fluid. This has the advantage that no recirculation elements need to be provided. However, it is also conceivable that the working fluid flows in a closed circuit. This will be explained in more detail below.

[0031] In summary, the inventors have recognized that it is particularly advantageous for the process if the working medium is separated into a liquid and a gaseous component before the introduction of external energy, and the external energy is transferred only to the liquid component of the working medium, thereby increasing the energy efficiency of the process according to the invention. Furthermore, the inventors have recognized that the externally supplied energy can be utilized or converted by means of the ejector in such a way that the gaseous suction fluid can be raised to a higher temperature and pressure level without requiring any additional energy input. The increased temperature and pressure level, for example, increases the applicability of the supplied working fluid and reduces any transport losses. Thus, the process enables the supply of a working fluid for heat transfer in an energy-efficient manner.At the same time, the method according to the invention reduces the requirements for the dimensioning of the components, thereby in particular lowering the installation space required to carry out the method.

[0032] In another embodiment, the method further includes the step: - Returning the utility fluid to at least one further phase separator.

[0033] The recirculation of the useful fluid preferably takes place after it has been supplied, particularly after the energy supplied by the useful fluid has been transferred to an environment, such as in a further heat exchanger. The useful fluid can be present in two-phase form during recirculation. Recirculation can be achieved, for example, via suitable pipelines and / or an additional throttling element. Recirculating the useful fluid into the at least one further phase separator has the effect of allowing energy not yet transferred to the environment by the useful fluid—that is, energy still contained in the useful fluid upon recirculation—to be further utilized. For example, the gaseous component of the recirculated useful fluid can be supplied again as gaseous useful fluid. This has a particularly advantageous effect on the energy efficiency of the process.

[0034] The liquid portion of the recycled useful fluid, on the other hand, can be returned as a by-fluid from the at least one further phase separator via the throttling element to the at least one first phase separator.

[0035] In another embodiment, the working fluid flows in a closed loop. In other words, the components necessary for carrying out the process are fluidically connected in such a way that the quantity of the working fluid remains almost constant and can be used for virtually any number of process cycles. This has the advantage that no new working fluid is required or needs to be added to the process. Furthermore, this ensures that the quality of the working fluid remains consistent and that the available working fluid can be used in a resource-efficient manner.

[0036] In a further embodiment, the working medium is supplied as a fluid via a supply device. The supply device can, for example, be designed as a valve. Preferably, the supply device is arranged on the at least one first phase separator and / or the at least one further phase separator. However, the supply device can also be arranged on another component. Preferably, the quantity of the supplied working medium corresponds to the quantity of the provided working fluid – particularly if the working medium flows in an open circuit. This ensures that sufficient working medium flows in to carry out the process according to the invention. Furthermore, supplying the working medium offers the advantage that state variables of the working medium, such as pressure, temperature, or the quality of the working medium, can be set before supply, which is advantageous, for example,which can have a beneficial effect on the efficiency of the process.

[0037] In another embodiment, the working medium is water. Water as a working medium has the advantage that, compared to other refrigerants, it is environmentally friendly, non-flammable, and readily available. Furthermore, many industrial plants, especially steam systems, operate with water, so that the useful fluid provided for heat transfer can be directly processed further or fed into the corresponding steam system, thus eliminating the need for a primary and secondary circuit or an additional heat exchanger. Therefore, using water as the working medium for the process results in increased environmental friendliness and user-friendliness.

[0038] In another embodiment, the method further includes the step: - Compressing and heating the user fluid using at least one compressor element.

[0039] The compressor element can be designed, for example, as an axial or radial compressor. The compressor element is, for example, electrically driven. Preferably, the compression and heating of the service fluid takes place before the service fluid is made available for heat transfer. More preferably, the compression and heating of the service fluid takes place in at least one further phase separator after the mixing fluid has been separated into the service fluid and the by-product fluid. The gaseous service fluid is compressed and heated by the compressor element, which in particular further increases the enthalpy of the service fluid. In particular, the compression and heating of the service fluid takes place without a phase transition, i.e., the service fluid remains in gaseous form during compression and heating. The compression and heating by means of the compressor element has a particularly advantageous effect on the achievable pressure and temperature level of the service fluid provided. For example,A higher flow temperature can be achieved, and the working fluid can transfer heat to the environment at a correspondingly higher temperature level.

[0040] The inventors further recognized that by using at least one ejector, the working fluid can be supplied to the at least one compressor element at a pressure level that reduces the compression ratio required by the compressor element. This means, for example, that less drive power is sufficient to power the compressor element. Thus, there is a synergistic effect between the use of an ejector and the use of a compressor element. This has a beneficial effect on the energy efficiency of the process. Furthermore, the dimensioning and design of the compressor element is significantly simplified by the already high pressure level. For example, the compressor element can advantageously be operated with fewer compressor stages and / or at an overpressure level, so that, for example, a corresponding seal against the environment can be omitted.

[0041] In another embodiment, the method further includes the step: - Cooling of the usable fluid in at least one further heat exchanger.

[0042] The at least one additional heat exchanger can, for example, be designed as a shell-and-tube heat exchanger. Preferably, the cooling of the service fluid takes place in the at least one compressor element after compression and heating. Furthermore, the cooling of the service fluid can also correspond to the supply of the service fluid. For the purpose of cooling the service fluid, the additional heat exchanger can be surrounded by another ambient fluid, which has a lower temperature than the service fluid upon contact with the heat exchanger. Due to the temperature difference between the service fluid and the environment or the other ambient fluid, thermal energy can be transferred from the service fluid to the environment. This can, for example, be used to heat a building. Through cooling, the service fluid can at least partially transition from a gaseous to a liquid state. In particular, the service fluid can exist in a two-phase form after cooling.

[0043] Preferably, after cooling, the working fluid is at least partially, and particularly preferably completely, returned to the at least one further phase separator, e.g., via pipelines. The resulting advantages have already been explained.

[0044] In another embodiment, the ratio of the propellant fluid mass flow rate to the suction fluid mass flow rate is greater than 20. This ratio is almost proportional to the achievable pressure increase in the suction fluid. Therefore, a particularly high compression of the suction fluid can be achieved with a ratio greater than 20. The increased pressure level results, for example, in the advantages previously described for supplying the working fluid for heat transfer.

[0045] In a further embodiment, the ratio of the operating pressure of the at least one additional phase separator to the operating pressure of the at least one first phase separator is greater than or equal to 1.1. The correspondingly higher operating pressure in the at least one additional phase separator directly affects the pressure level of the suction fluid relative to the pressure level of the mixing or working fluid. In other words, the pressure level between the suction fluid and the working fluid is increased by at least 10% by the method according to the invention. The advantages resulting from an increased pressure level have already been explained.

[0046] A further proposed device for heat transfer is comprising: - at least one first phase separator and one further phase separator, - at least one ejector, - at least one pump element, - at least one heat exchanger, - at least one throttle element, the device is designed to perform the following steps: - Separation of a working medium into a liquid propellant fluid and a gaseous suction fluid by means of at least one first phase separator, - Increasing the pressure in the propellant fluid by means of at least one pump element, - Heating the motive fluid without phase transition in at least one heat exchanger, - Suction of the suction fluid with the help of the propellant fluid and generation of a two-phase mixed fluid from the suction fluid and the propellant fluid in the ejector, - Separation of the mixed fluid into a liquid secondary fluid and a gaseous primary fluid by means of at least one further phase separator, - Returning the bypass fluid from the further phase separator to the first phase separator via the at least one throttling element, - Providing the working fluid for heat transfer.

[0047] The device is further configured to carry out a method according to one or more of the embodiments described in this disclosure. The device thus provides the technical effects and advantages previously described for the method.

[0048] The device, or one or more components, can be arranged in a housing. Furthermore, the device, or one or more components, can each have at least one interface for fluidic connection with another component and / or the environment. This allows the device to be integrated, for example, particularly easily into existing industrial plants.

[0049] The invention is explained in more detail using exemplary embodiments. The figures show: Fig. 1 a schematic representation of an embodiment of a device according to the invention, Fig. 2 a schematic pressure-enthalpy diagram, Fig. 3 a schematic temperature-entropy diagram, and Fig. 4 a schematic flowchart of an embodiment of a method according to the invention.

[0050] In the following, identical reference symbols denote elements with the same or similar technical characteristics.

[0051] Fig. Figure 1 shows an embodiment of a device 100 according to the invention. The device 100 comprises several components which are fluidically connected to one another, e.g., via pipelines. A working medium, namely water, flows through the pipelines from one component of the device 100 to the next, the respective flow direction of the working medium between the components being... Fig. 1 is represented by arrows.

[0052] The device 100 comprises according to Fig. 1 The following components: a first phase separator 20 designed as a settling tank, a pump element 30 designed as a radial pump, a heat exchanger 40 designed as a recuperator, an ejector 50 designed as a jet pump, a further phase separator 60 designed as a settling tank, a throttling element 70 designed as a throttle valve, and a compressor element 80 designed as a radial compressor. Each of the components is designed for at least one change of state of the fluid in the Fig. 2 and Fig. The device 100 is responsible for the thermodynamic process shown schematically in section 3. Furthermore, the device 100 comprises a feed device 90 designed as a feed valve, through which the working medium is supplied to the device 100 as a two-phase fluid.

[0053] Fig. Figure 2 shows a schematic, idealized pressure-enthalpy or pH diagram for an embodiment of a method according to the invention. Fig. Figure 3 shows a corresponding, schematic, and also idealized temperature-entropy (Ts) diagram for an embodiment of a method according to the invention. The endpoints of the process marked by reference numerals 1 to 10 denote idealized states of the working medium to which none of the components of the device 100 brings about a change of state. In other words: The values ​​shown in the Fig. 2 and Fig. The three state changes shown between the marked corner points are specifically targeted using the in Fig. 1 components of the device 100 shown.

[0054] Furthermore, in Fig. 2 and Fig. Figure 3 shows a phase boundary line, which divides the respective state space into three regions of different phases. Thus, the left region – with corner points 2, 3, 4 and 8 – is assigned to the liquid phase, the middle region – with corner points 1, 5 and 9 – is assigned to the wet steam phase or the two-phase form, and the right region – with corner points 6, 7 and 10 – is assigned to the superheated steam phase or the gaseous form.

[0055] Fig. Figure 4 shows a schematic flowchart of an embodiment of a method according to the invention. The method steps S0 to S8 are explained below. It should be noted that steps S0 to S8 can of course be carried out simultaneously, so that the thermodynamic process can be carried out continuously.

[0056] In a first step S0, the working medium is fed as a two-phase fluid to the first phase separator 20 via the feed device 90. This ensures that a sufficient working medium is always available in the device 100 to carry out the method according to the invention.

[0057] In a further step S1, the working fluid is separated into a liquid propellant TF and a gaseous suction fluid SF. This separation divides the working fluid into a low-enthalpy and low-entropic liquid fraction (change of state 1 to 2) and a comparatively high-enthalpy and high-entropic gaseous fraction (change of state 1 to 10). See also Fig. 1 to Fig. 3.

[0058] In a further step S2, the pressure of the motive fluid TF is increased by means of the pump element 30. This corresponds to the change of state from 2 to 3. The enthalpy, entropy and temperature of the motive fluid TF also increase slightly with the pressure increase (cf. Fig. 1 to Fig. 3).

[0059] In a further step S3, the motive fluid TF in the heat exchanger 40 is heated by means of a heat source, such as a waste heat stream from an industrial process, whereby the change of state from 3 to 4 is accompanied by an increase in temperature, entropy, and enthalpy of the motive fluid TF (cf. Fig. 1 to Fig. 3) In this process, the motive fluid TF remains liquid due to the prior pressure increase, so that the heat exchanger 40 advantageously manages, for example, without a steam space. This reduces the installation space required for carrying out the process according to the invention and makes it possible to tap into previously unused heat sources.

[0060] In a further step S4, the liquid propellant TF is accelerated in the ejector 50, e.g., by means of a propellant nozzle, whereby the propellant TF can at least partially evaporate. Thus, in the change of state from 4 to 5, some of the energy supplied to the propellant TF is converted into kinetic energy, whereby in particular the pressure of the propellant TF drops. Due to the resulting pressure difference between the propellant and suction fluid TF, SF (in Fig. 2 and Fig. (3 not shown), the suction fluid SF is drawn from the first phase separator 20 into the ejector 50. Furthermore, e.g. in a mixing tube of the ejector 50, the propellant fluid TF and the suction fluid SF are mixed to form a two-phase mixing fluid MF, which – according to the change of state from 10 to 5 – has a higher pressure and a higher temperature than the suction fluid SF (cf. Fig. 1 to Fig. 3) In other words: With the help of the liquid propellant TF, the gaseous suction fluid SF in the ejector 50 is brought to a higher pressure level.

[0061] In a further step S5, the mixed fluid MF is separated in the further phase separator 60 into a gaseous working fluid NU and a liquid secondary fluid NB. This separation thus divides the mixed fluid MF into a comparatively high-enthalpy and high-entropic gaseous fraction (state change from 5 to 6) and a low-enthalpy and low-entropic liquid fraction (state change from 5 to 8) (cf. Fig. 1 to Fig. 3) The pressure level of the two-phase mixed fluid MF is maintained for the gaseous working fluid NU as well. In summary, the process according to the invention raises the gaseous component of the working medium, here the working fluid NU, to a high pressure level, particularly compared to the surroundings.

[0062] In a further step S6, the liquid by-fluid NB is returned from the further phase separator 60 – in contrast to the main fluid NU – to the first phase separator 20 via the throttling element 70. This corresponds to the change of state from 8 to 9, whereby the by-fluid NB is expanded and cooled by means of the throttling element 70, so that the by-fluid NB is present in two-phase form in the first phase separator 20 (cf. Fig. 1 to Fig. 3) By returning the bypass fluid NB from the secondary phase separator 60 to the first phase separator 20, a mass flow is generated in the secondary phase separator 60, which facilitates the supply of the useful fluid NU, as more mixing fluid MF can flow into the secondary phase separator 60. Furthermore, a difference in operating pressures between the first phase separator 20 and the secondary phase separator 60 is maintained by means of the throttling element 70.

[0063] In a further step S7, the gaseous utility fluid NU is drawn in by a compressor element 80, e.g., electrically driven, and further compressed. Because the pressure level of the utility fluid NU is already higher than that of the surroundings, the compressor element 80 can operate without a corresponding vacuum seal against the surroundings. Furthermore, the compressor element 80 can be operated, e.g., with lower power consumption—especially compared to a compressor that generates the entire pressure level. This has a beneficial effect on the energy efficiency of the process. The compression of the utility fluid NU by means of the compressor element 80 corresponds to the change of state from 6 to 7, whereby the pressure and temperature levels of the utility fluid NU continue to rise (cf. Fig. 1 to Fig. 3) In particular, a correspondingly high flow temperature can be achieved using the method according to the invention.

[0064] In a further step S8, the compressed and heated utility fluid NU is made available for heat transfer, e.g., for heat transfer to a building's heating circuit via a further heat exchanger (not shown). In particular, due to the compression and heating by means of the utility fluid NU, heat transfer to a heat sink at a significantly higher temperature level than the heat source is also possible. Reference symbol list 1 ... 10 Key aspects of the thermodynamic process 20 first phase separator 30 Pump element 40 heat exchangers 50 ejector 60 additional phase separators 70 Throttle element 80 compressor element 90 Feeding device 100 Device h Enthalpy p print NB secondary fluid NU utility fluid MF Mixing Fluid s entropy S0 first step S1 further step S2 further step S3 further step S4 further step S5 further step S6 further step S7 further step S8 further step SF Absorbent Fluid Temperature TF propellant fluid

Claims

[1] Heat transfer process comprising the steps: - Separation (S1) of a working medium into a liquid propellant fluid (TF) and a gaseous suction fluid (SF) by means of at least one first phase separator (20), - Increase (S2) of the pressure in the propellant fluid (TF) by means of at least one pump element (30), - Heating (S3) of the motive fluid (TF) without phase transition in at least one heat exchanger (40), - Suction (S4) of the suction fluid (SF) with the aid of the propellant fluid (TF) and generation of a two-phase mixed fluid (MF) from the suction fluid (SF) and the propellant fluid (TF) in at least one ejector (50), - Separation (S5) of the mixed fluid (MF) into a liquid subsidiary fluid (NB) and a gaseous useful fluid (NU) by means of at least one further phase separator (60), - Return (S6) of the bypass fluid (NB) from the further phase separator (60) to the at least one first phase separator (20) via at least one throttling element (70), - Providing (S8) the utility fluid (NU) for heat transfer. [2] Method according to claim 1, characterized by , that the procedure further includes the step: - Returning the utility fluid (NU) to at least one further phase separator (60). [3] Method according to claim 1 or 2, characterized by that the working medium flows in a closed circuit. [4] Method according to any of the preceding claims, characterized by , that the working medium is supplied as a fluid via a supply device (90). [5] Method according to any of the preceding claims, characterized by that the working medium is water. [6] Method according to any of the preceding claims, characterized by , that the procedure further includes the step: - Compression (S7) and heating of the useful fluid (NU) by means of at least one compressor element (80). [7] Method according to any of the preceding claims, characterized by , that the procedure further includes the step: - Cooling of the useful fluid (UF) in at least one further heat exchanger. [8] Method according to any of the preceding claims, characterized by , that the ratio of the mass flow rate of the propellant fluid (TF) to the mass flow rate of the suction fluid (SF) is greater than 20. [9] Method according to any of the preceding claims, characterized by , that the ratio of the operating pressure of the at least one further phase separator (60) to the operating pressure of the at least one first phase separator (20) is greater than or equal to 1.

1. [10] Heat transfer device (100) comprising: - at least one first phase separator (20) and one further phase separator (60), - at least one pump element (30), - at least one heat exchanger (40), - at least one ejector (50), - at least one throttle element (70), wherein the device (100) is configured to perform the following steps: - Separation (S1) of a working medium into a liquid propellant fluid (TF) and a gaseous suction fluid (SF) by means of the at least one first phase separator (20), - Increase (S2) of the pressure in the propellant fluid (TF) by means of the at least one pump element (30), - Heating (S3) of the motive fluid (TF) without phase transition in the at least one heat exchanger (40), - Suction (S4) of the suction fluid (SF) with the help of the propellant fluid and generation of a two-phase mixed fluid (MF) from the suction fluid (SF) and the propellant fluid (TF) in the ejector (50), - Separation (S5) of the mixed fluid (MF) into a liquid subsidiary fluid (NB) and a gaseous useful fluid (NU) by means of at least one further phase separator (60), - Return (S6) of the bypass fluid (NB) from the further phase separator (60) to the first phase separator (20) via the at least one throttling element (70), - Providing (S8) the utility fluid (NU) for heat transfer.

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