Ejector-optimized absorption heat transformer

Abstract

Absorption heat transformer optimized by ejector The invention relates to an absorption heat transformer (AHT), intended for the production of high temperature heat comprising an evaporator (2), an absorber (3) both operating at high pressure, a generator (4) operating at low pressure and a condenser (5), the transformer (1) comprises an ejector (6) placed between the generator (4) and the condenser (5), and a fluid bypass (B) arranged, between the evaporator (2) and the ejector (6), in bypass of a fluid connection (A) connecting the evaporator (2) to the absorber (3), and the ejector (6) comprises a primary fluid inlet (60) at high pressure in fluid connection with the evaporator (2) by the fluid bypass (B),a secondary fluid inlet (61) at low pressure in fluid connection with an outlet (41) of the generator (4) and a mixing outlet (62) at intermediate pressure in fluid connection with an inlet (51) of the condenser (5), the condenser (5) operating at intermediate pressure. Figure for the abstract: Fig.1,

Description

Title of the invention: Ejector-optimized absorption heat transformer Technical field

[0001] The present invention relates to an ejector-optimized absorption heat transformer. The invention will find its application for the production of high-temperature heat, typically above 100°C, for industry, which is efficient even when the atmosphere is hot. STATE OF THE ART

[0002] To date, 26% of industrial heat demand concerns temperatures of 100°C to 200°C, with a strong need for decarbonization to meet the objective of net zero CO2 emissions by 2050.

[0003] Among the solutions that can be implemented to achieve these objectives, high-temperature heat pumps (above 100°C) are promising technologies. However, many technological barriers related to the performance and manufacturing of compressors as well as the use of low CO2 impact refrigerants must be removed. An emerging solution is to replace compressors with an ammonia / water absorption system (NH3 / H2O). This technology can contribute to reducing final energy consumption, in accordance with the indications contained in the European Energy-Climate Framework 2030 and formalized in France by the LTECV (Law for the Energy Transition and Green Growth) promulgated in 2015.

[0004] Absorption heat pumps, also known as absorption heat transformers (AHT), require cooling at the condenser. This cooling is typically achieved by air heaters with heat discharges to the environment. However, when the environment is hot, for example in summer, from around 25°C, this type of device tends to lose its efficiency very quickly, or even stop working.

[0005] There is therefore a need for an ecological, economical and efficient high temperature heat production device for hot outside temperatures from 25°C for example. SUMMARY

[0006] To achieve this objective, according to one embodiment, an absorption heat transformer is provided for the production of high-temperature heat, comprising a fluid circuit receiving a working solution formed of a refrigerant / absorbent couple and successively comprising in fluid connection: an evaporator, preferably operating at high pressure, an absorber preferably operating at high pressure and intended for the production of high temperature heat, a generator (4) preferably operating at low pressure and a condenser, the fluid circuit comprises a pump arranged between the condenser and the evaporator, a solution pump arranged between the generator and the absorber, and an expansion valve arranged in parallel with the solution pump between the absorber and the generator, the transformer comprises, arranged on the fluid circuit, an ejector placed between the generator and the condenser, and a fluid bypass arranged, between the evaporator and the ejector, in bypass of a fluid connection connecting the evaporator to the absorber,and the ejector comprises a primary fluid inlet preferably at high pressure in fluid connection with the evaporator by the fluid bypass, a secondary fluid inlet preferably at low pressure in fluid connection with an outlet of the generator and a mixing outlet preferably at intermediate pressure in fluid connection with an inlet of the condenser, preferably the condenser operating at intermediate pressure.

[0007] The architecture of this absorption heat transformer comprising an ejector makes it possible to guarantee the recovery of heat in wider real operating conditions than the systems of the state of the art.

[0008] The heat transformer according to the invention makes it possible to generate high-temperature heat, advantageously at least 100°C, from a medium-temperature heat source, preferably waste heat having a temperature of the order of at least 80°C, while consuming little electrical energy, even when the outside temperature exceeds 25°C.

[0009] The ejector thus arranged defines an intermediate pressure at the condenser which ensures condensation of refrigerant from the working solution even with a cold source at the hotter condenser, in particular above 25°C without modifying the low pressure prevailing at the generator and ensuring optimal operation of the heat transformer and therefore the production of heat at the absorber.

[0010] According to another aspect, the invention relates to a method for producing high-temperature heat by an absorption heat transformer, as described above and further in the description, comprising the circulation of a flow of working solution formed by a refrigerant / absorbent couple and a flow of refrigerant in the fluid circuit, the primary fluid inlet of the ejector is supplied by at least a portion of a flow of refrigerant in the gaseous state and at high pressure coming from the evaporator and that the secondary fluid inlet of the ejector is supplied by the entire flow of refrigerant in the gaseous state and at low pressure coming from the generator and that the ejector produces a mixture of refrigerant at intermediate pressure exiting through the mixture outlet in fluid connection with the condenser operating at intermediate pressure. BRIEF DESCRIPTION OF THE FIGURES

[0011] The aims, objects, as well as the characteristics and advantages of the invention will emerge more clearly from the detailed description of an embodiment thereof which is illustrated by the following accompanying drawing:

[0012] [Fig.l] [Fig.l] represents a diagram of the heat transformer according to the invention.

[0013] The drawing is given by way of example and is not limiting of the invention. It constitutes a schematic representation of principle intended to facilitate the understanding of the invention and is not necessarily on the scale of practical applications. DETAILED DESCRIPTION

[0014] Before beginning a detailed review of embodiments of the invention, optional features which may possibly be used in combination or alternatively are set out below:

[0015] - According to one example, the refrigerant / absorbent couple forming the working solution is ammonia / water (NH3 / H2O);

[0016] - According to one example, the low pressure is lower than the medium pressure which is itself lower than high pressure;

[0017] - According to one example, the low pressure is less than or equal to 9 bar, the high pressure is greater than or equal to 25 bar and the intermediate pressure is greater than 10 bar and less than 20 bar;

[0018] - According to one example, the transformer comprises at least one control member, preferably a three-way valve, arranged on the fluid circuit at the junction between the fluid bypass B and the fluid connection A and a control unit configured to control the control member so as to ensure the distribution of the refrigerant to the absorber 3 and / or the ejector 6;

[0019] - According to one example, the condenser 5 comprises a cold source 13 intended to ensure cooling within the condenser 5, the cold source 13 being at a maximum temperature less than or equal to 45°C;

[0020] - According to one example, at least one control member, preferably a valve three-way, arranged on the fluid circuit at the junction of fluid bypass B and fluid connection A and a control unit configured to control the control member ensures the regulation of the flow of refrigerant from the evaporator and transmitted to the ejector 6 and the refrigerant flow from the evaporator and transmitted to the absorber 3;

[0021] - According to one example, the condenser 5 comprises a cold source 13 intended to ensure cooling within the condenser 5, the cold source 13 being ambient air at a maximum temperature less than or equal to 45°C;

[0022] - According to one example, the low pressure is less than or equal to 9 bar, the high pressure is greater than or equal to 25 bar and the intermediate pressure is greater than 10 bar and less than 20 bar.

[0023] In the present description, the expression "A fluidically connected to B" is synonymous with "A is in fluidic connection with B" does not necessarily mean that there is no member between A and B. The expressions "arranged on" or "on" are synonymous with "fluidically connected to".

[0024] The upstream and downstream at a given point are taken in reference to the direction of circulation of the fluid in the circuit.

[0025] Hot, cold, cooled means a temperature relative to another point in the system.

[0026] A parameter "substantially equal / greater / less than" or "of the order of" a given value means that this parameter is equal / greater / less than the given value, to within plus or minus 10%, or even to within plus or minus 5%, of this value.

[0027] The terms "first", "second" and "third", etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

[0028] The absorption heat transformer (TCA) 1 operates with a different cycle from an absorption machine where the production of cold is sought. Here, it is a production of heat which is sought. The absorption heat transformer 1 is supplied by a heat source 11 at the generator 4, for example at a temperature of the order of 70-80°C and produces at the absorber 3 a heated source 14 at a temperature greater than or equal to 100°C.

[0029] Advantageously, the heat source 11 is waste heat from industrial processes for example or heat produced by renewable energy.

[0030] An absorption heat transformer 1 is a thermal absorption heat pump using a working solution based on refrigerant / sorbent couples with strong affinities. This transformer has low electrical consumption, the main energy coming from the thermal source, making it possible to limit the operating cost in the case of the recovery of a low-cost energy source or fatal heat. In addition, the refrigerants or coolants used in absorption heat transformers 1 have no or very low environmental impact on global warming (GWP for Global warming potential or GWP for Global Warming Potential = 0), or on the ozone layer (ODP for Ozone depletion potential or PDO for ozonic depletion potential = 0).

[0031] This type of heat transformer works thanks to the ability of certain liquids to absorb (exothermic reaction) and desorb (endothermic reaction) a vapor. They also use the fact that the solubility of this vapor in the liquid depends on the temperature and pressure. Thus, these transformers use as a working solution a binary mixture, one of the components of which is more volatile than the other, and constitutes the refrigerant.

[0032] The absorption heat transformer 1 comprises an absorption fluid circuit configured to ensure the fluid connection of the different components of the absorption heat transformer 1. The absorption fluid circuit is a closed circuit intended to receive the working solution.

[0033] According to one embodiment of the invention, the TCA 1 comprises a working solution comprising the refrigerant / absorbent fluid pair chosen from preferably the ammonia / water pair (NH3 / H2O) or possibly the water / Lithium Bromide pair (H2O / LiBr).

[0034] According to the invention, the NH3 / H2O pair can be used for heating applications. In addition, this pair allows working at pressure higher than ambient pressure.

[0035] This thermodynamic cycle is achievable due to the difference in vapor pressure between the absorbent and the refrigerant which is variable depending on the temperature and the pressure. This variability makes it possible to have a difference in concentration between the lean solution and the rich solution described below.

[0036] The advantage of this absorption cycle is that mechanical compression is replaced by thermochemical compression which produces heat. The only primary energy input required is at pumps 7 and 8, but the work is about 96 times less than the work that a steam compressor must provide for similar operating conditions.

[0037] The working solution is said to be rich, because the concentration of refrigerant fluid is greater than in the so-called lean working solution.

[0038] An absorption heat transformer 1 (TCA) comprises four main exchangers, evaporator 2, absorber 3, generator 4 and condenser 5, and advantageously one to three secondary exchangers.

[0039] The role of the three secondary exchangers is to improve the performance of the machine: a rectifier (not shown) arranged between the generator 4 and the condenser 5, a first economizer 15 arranged between the condenser 5 and the evaporator 2 for play the role of preheating and a second economizer 16 arranged between the absorber 3 and the generator 4 on the solution circuit described below.

[0040] According to one possibility, the TCA 1 also comprises at least one solution pump 8 and a pressure reducer 9 also called an expansion valve.

[0041] According to the invention, the TCA 1 comprises a pump 7 arranged between the condenser 5 and the evaporator 2.

[0042] The refrigerant (or coolant) of the working solution produced in the generator 4 circulates between the outlet 41 of the generator 4 and the inlet 30 of the absorber 3, passing successively through the ejector 6, then preferably the first economizer 15, then the condenser 5, then the second side of the economizer 15, then the evaporator 2, then the ejector 6 and / or the absorber 3, more precisely in the fluid connections A, B, I, J, K, L, M, N. The refrigerant-absorbent solution rich in absorbent (high concentration of absorbent) but poor in refrigerant, commonly called lean solution, circulates from the generator 4 to the absorber 3 in the solution circuit, more precisely in the fluid connections F, G, H.The solution poor in absorbent (low concentration of absorbent) but rich in refrigerant, commonly called rich solution, circulates from absorber 3 to generator 4 in the solution circuit, more precisely in fluid connections C, D E. .

[0043] This type of TCA 1 operates according to three temperature levels: a low temperature level corresponding to the temperature of the cold source 13 circulating in the condenser 5, preferably the temperature is said to be low when it is less than or equal to 45°C, an intermediate temperature level corresponding to the temperature of the hot source 10 and of the hot source 11 advantageously corresponding respectively to the evaporation temperature of the refrigerant in the evaporator 2, but also to the driving temperature of the generator 4, preferably the temperature is said to be intermediate when it is greater than or equal to 80°C and less than 100°C and a high temperature level corresponding to the temperature of the source to be heated circulating in the absorber 3 advantageously corresponding to the absorption temperature in the absorber 3 preferably the temperature is said to be high when it is greater than or also 100°C.

[0044] According to the invention, the absorption heat transformer 1 comprises an ejector 6. The injector 6 is arranged between the generator 4 and the condenser 3 and between the evaporator 2 and the condenser 5.

[0045] The ejector 6 is a simple, inexpensive component with no moving parts configured to mix a high-pressure primary fluid and a low-pressure secondary fluid so as to produce an exiting mixture at intermediate pressure. Preferably, the primary fluid is in the gaseous state. Preferably, the secondary fluid is in the gaseous state. Preferably, the exiting mixture is in the gaseous state.

[0046] The fluid circuit ensures the fluid connection of the components of the TCA 1. More precisely, the fluid circuit comprises the different components and fluid connections arranged between the different components.

[0047] According to the invention, the fluid circuit ensures the fluid connection of the generator 4 to the ejector 6, of the ejector 6 to the condenser 5, of the condenser 5 to the evaporator 2, of the evaporator 2 to the absorber 3 and of the evaporator 2 to the ejector 6, of the absorber 3 to the generator 4 and of the generator 4 to the absorber 3.

[0048] The ejector 6 comprises a primary fluid inlet 60 fluidly connected to the outlet 21 of the evaporator 2, either directly or partially by a fluid connection and a possible control member, and a secondary fluid inlet 61 fluidly connected to the outlet 41 of the generator 4. The injector 6 comprises a mixture outlet 62 fluidly connected to the inlet 50 of the condenser 5, either directly or preferably by passing through the first economizer 15.

[0049] The presence of the ejector 6 on a heat transformation cycle by absorption makes it possible to define three pressure levels on the transformer 1. Advantageously, the evaporator 2 and the absorber 3 operate respectively at a pressure which may or may not be identical and which corresponds to a so-called high pressure, while the generator 4 operates at a pressure corresponding to a so-called low pressure, and the condenser 5 operates at a pressure corresponding to a so-called intermediate pressure. Advantageously, the ejector 6 makes it possible to generate an intermediate pressure.The passage from a high pressure to a low pressure from the absorber 3 to the generator 4, preferably at the level of the solution circuit described below, is ensured by the pressure reducer 9 while the passage from a low pressure to a high pressure from the generator 4 to the absorber 3, preferably at the level of the solution circuit described below, is ensured by the solution pump 8.

[0050] High pressure is understood to mean a pressure preferably greater than or equal to 25 bars (i.e. 2,500 KPa), low pressure is understood to be a pressure preferably less than or equal to 9 bars (i.e. 900 KPa) and intermediate pressure is understood to be a pressure between high pressure and low pressure, for example greater than 10 bars (i.e. 1,000 KPa) and less than 20 bars (i.e. 2,000 KPa).

[0051] The ejector 6 decouples the pressure level between the generator 4 and the condenser 5. The generator 4 is capable of producing steam that the condenser 5 can then condense regardless of the temperature of the cold source 13 circulating in the condenser 5, preferably less than or equal to 45°C and possibly greater than or equal to 25°C. The use of an ejector 6 makes it possible to guarantee the operation of the heat transformer 1 by absorption in all seasons and to supply heat uninterruptedly throughout the year.

[0052] The absorption heat transformer 1 according to the invention comprises a generator 4 described in detail below.

[0053] The generator 4 is configured to vaporize the refrigerant. The generation of refrigerant vapor is carried out at a pressure corresponding to a low pressure. The generator 4 is thus configured to operate at a pressure corresponding to a low pressure.

[0054] The so-called rich working solution coming from the absorber 3 is heated by a heat source 11 advantageously corresponding to a medium-temperature source to be recovered which passes through the generator 4. Thanks to this heat, part of the refrigerant fluid, for example ammonia, contained in the rich solution as well as traces of water are desorbed. The depleted working solution resulting from this process returns to the absorber 3, preferably via the solution circuit. The desorption process takes place at low pressure, and requires a quantity of heat. The refrigerant vapor produced by the generator 4, also sometimes called a desorber, is conveyed to the condenser 5, sometimes via a rectifier, and a first economizer 15 and according to the invention via an ejector 6.

[0055] The generator 4 is fluidically connected to the absorber 3 and to the ejector 6. The generator 4 advantageously comprises an inlet 40 for the working solution, preferably a so-called rich working solution, in fluidic connection, preferably indirect with the absorber 3, more precisely with an outlet 31 of the absorber 3, so as to supply the generator 4 with so-called rich working solution. The refrigerant of the rich working solution is then vaporized in the generator 4. The so-called lean working solution returns to the absorber 3 via an outlet 42. The generator 4 advantageously comprises an outlet 42 for the working solution, preferably a so-called lean working solution in fluidic connection, preferably indirect with the absorber 3, more precisely with the inlet 32 ​​of the absorber 3, so as to supply the absorber 3 with so-called lean working solution. The generator 4 includes an outlet 41 for the vaporized refrigerant.The outlet 41 is fluidically connected with the secondary fluid inlet 61 of the ejector 6. .

[0056] Advantageously, the absorption heat transformer 1 comprises, between the generator 4 and the absorber 3, a second economizer 16, an expander 9 and a solution pump 8. These components are arranged on a fluid circuit called the solution circuit. The second economizer 16 and the expander 9 ensure the circulation of the working solution from the absorber 3 to the generator 4 and conversely the second economizer 16 and the solution pump 8 ensure the circulation of the working solution between the generator 4 and the absorber 3. More specifically, the so-called rich working solution and the so-called lean working solution circulate respectively from the absorber 3 to the generator 4 via the second economizer 16 and the expander 9 and from generator 4 to absorber 3 via solution pump 8 and second economizer 16.

[0057] The generator 4 comprises a fluid connection with the condenser 5 on which the ejector 6 is arranged. The generator 4 is thus fluidically connected directly to the ejector 6, and indirectly to the condenser 5, allowing the refrigerant vapor to exit the generator 4. The generator 4 also comprises a heat source inlet and outlet 11 allowing the supply of heat necessary for the vaporization of the refrigerant. According to the invention, the heat source 11, or hot source, comprises at least partially, preferably only fatal energy at a temperature of the order of 70°C minimum, preferably greater than or equal to 80°C.

[0058] The absorption heat transformer 1 according to the invention comprises a condenser 5 described in detail below.

[0059] The condenser 5 is configured to condense the refrigerant vapor from the generator 4. The refrigerant vapor is cooled by a cold source 13 to be condensed and become liquid again. According to the invention, the condensation of the refrigerant vapor is carried out at a pressure corresponding to an intermediate pressure. The condenser 5 is configured to operate at a pressure corresponding to an intermediate pressure, which makes it possible to use a cold source 13 at a higher temperature than in an absorption heat transformer of the state of the art.

[0060] The condenser 5 is fluidically connected to the generator 4 and to the evaporator 1. The condenser 5 comprises a fluid connection J, K, coming from the ejector 6 allowing the entry of a flow of refrigerant vapor into the condenser 5, preferably directly or through a rectifier and / or a first economizer 15. The flow of refrigerant vapor arriving in the condenser 5 is advantageously at a fifteenth pressure called intermediate pressure. For example, the flow of refrigerant vapor is at a sixteenth pressure of 15 bars (i.e. 1,500 KPa).

[0061] The condenser 5 comprises an inlet 50 for the flow of refrigerant vapor and an outlet 51 for the flow of refrigerant having been condensed.

[0062] The condenser 5 comprises a fluid connection, L, M, N with the evaporator 2 allowing the refrigerant to exit in the liquid state, advantageously through a pump 7 intended to bring the refrigerant to its evaporation pressure, preferably a seventeenth pressure corresponding to a high pressure. The condenser 5 also comprises a cold source 13 constituted at least partially according to the invention from ambient air. The cold source 13 circulates in the condenser 5 so as to ensure the cooling of the refrigerant vapor and thus allow its condensation.

[0063] According to a possibility not shown, the absorption heat transformer 1 comprises a rectifier arranged between the generator 4 and the condenser 5. The rectifier makes it possible to remove by condensation the traces of water carried along with the refrigerant fluid at the outlet of the generator 4, if the water content of the refrigerant vapor is too high, and thus ensures the operation of the transformer 1 under these conditions. Preferably, the rectifier is in this case arranged on the fluid connection I ensuring the fluid connection between the generator 4 and the ejector 6.

[0064] Advantageously, the absorption heat transformer 1 comprises a pump 7 arranged between the condenser 5 and the evaporator 2. The pump 7 is configured to compress the refrigerant in the liquid state coming from the condenser 5. The pump 7 advantageously comprises an inlet 70 for the flow of refrigerant in the liquid state at a twelfth pressure included in the intermediate pressure range and an outlet 71 for the flow of refrigerant in the liquid state at a thirteenth pressure included in the high pressure range.

[0065] Advantageously, the absorption heat transformer 1 comprises a first economizer 15 playing the role of preheating or superheating. The first economizer 15 is arranged between the condenser 5 and the evaporator 2. The first economizer 15 is a heat exchanger arranged on the fluid connection from the condenser 5 to the evaporator 2 and on the fluid connection from the ejector 6 to the condenser 5. Thus, the refrigerant fluid heated to intermediate pressure leaving the ejector 6 passes through the first economizer 15 to transmit part of its heat to the refrigerant fluid leaving the condenser 5, thus making it possible to preheat the refrigerant fluid before it enters the evaporator 2. The first economizer 15 makes it possible to recover energy and therefore to reduce the size of the condenser 5 and the evaporator 2 and thus to significantly improve the performance of the machine.The relevance of this component depends on the operating temperatures, the size of the machine and the cost of the exchangers.

[0066] The absorption heat transformer according to the invention comprises an evaporator 2 described in detail below.

[0067] The evaporator 2 is configured to vaporize the refrigerant. In this component, the pressure is high and a medium-temperature heat input is required to enable the evaporation of the refrigerant. The evaporator 2 is configured to operate at a pressure selected from a high-pressure range. More specifically, the flow of refrigerant circulating within the evaporator 2 has a pressure within the high-pressure range.

[0068] The evaporator 2 is fluidically connected to the condenser 5 and to the absorber 3. The evaporator 2 comprises a fluidic connection M coming from the condenser 5, more precisely according to the illustrated embodiment coming from the first economizer 15.

[0069] The evaporator 2 comprises a fluid connection A with the absorber 3, allowing the refrigerant vapor to exit, preferably directly. The evaporator 2 also comprises an inlet and an outlet of a heat source 10. The phase change of the refrigerant from the liquid state to the vapor state is accompanied by a transmission of heat from the hot source 10 to the refrigerant. The hot source 10 transmits heat and thus sees its temperature lower. According to one embodiment of the invention, the hot source 10 is advantageously the same hot source 11 supplying the generator 4.

[0070] The TCA 1 advantageously comprises a fluid bypass B arranged either in parallel with the fluid connection A, or directly from the outlet 21 of the evaporator 2. The fluid bypass B is arranged so as to allow the circulation of at least a portion of the flow of refrigerant in the gaseous state leaving the evaporator 2 in the ejector 6, preferably directly. The fluid bypass B is arranged as a bypass of the fluid connection A connecting the evaporator 2 to the absorber 3.

[0071] According to one embodiment, the TCA 1 comprises at least one control member (not shown) such as for example a three-way valve. The control member is advantageously arranged so as to control the distribution of the flow of refrigerant in the gaseous state coming from the evaporator 2 between the fluid connection A and the fluid bypass B, that is to say between the ejector 6 and the absorber 3. According to a preferred embodiment, the control member is arranged at the junction of the fluid bypass B on the fluid connection A.

[0072] According to a preference, the TCA 1 comprises a control unit configured to control the control member. Advantageously, the TCA 1 comprises various temperature and / or pressure and / or flow rate sensors distributed over the fluid circuit, whether on the components or on the fluid connections. Advantageously, the various sensors are connected to the control unit and preferably allow optimization of the control of the control member as a function of the different pressure and / or temperature and / or flow rate and / or heat requirements data at the source to be heated.

[0073] The control member is configured to ensure the distribution of the flow of refrigerant in the gaseous state coming from the evaporator 2 between the absorber 3 and the ejector 6 which can take any value between 0% of the flow transmitted to the ejector 6 and 100% of the flow transmitted to the absorber 3 to 100% of the flow transmitted to the ejector 6 and 0% of the flow transmitted to the absorber 3.

[0074] The absorption heat transformer 1 according to the invention comprises an absorber 3 described in detail below.

[0075] The absorber 3 is configured to condense the refrigerant vapor from the evaporator 2.

[0076] In this component, the pressure is high. The absorber 3 is configured to operate in a pressure range corresponding to the high pressure range. More specifically, the flows of refrigerant fluid and working solution circulating within the absorber 3 have a pressure included in the high pressure range.

[0077] The absorber comprises an inlet 30, an inlet 32 ​​and an outlet 31.

[0078] The inlet 30 is fluidically connected to the outlet 21 of the evaporator 2. The refrigerant vapor from the evaporator 2 enters the absorber 3 via the inlet 30.

[0079] The inlet 32 ​​fluidly connected to the outlet 42 of the generator 4. The absorbent, or working solution composed of water and a small fraction of refrigerant, also called lean solution, from the generator 4 enters the absorber 3 through the inlet 32 ​​and is distributed along the absorber 3. The lean solution absorbs the refrigerant vapor which comes from the evaporator 2 and becomes an enriched solution, close to its saturated condition.

[0080] The outlet 31 is fluidly connected to an inlet 40 of the generator 4. The rich solution leaves the absorber 3 through the outlet 31 to be transmitted to the generator 4. The absorption process occurs at high pressure, releasing a quantity of heat which is dissipated towards the source to be heated, the temperature of which is to be raised.

[0081] The absorber 3 is fluidically connected to the evaporator 2 and to the generator 4. The absorber 3 comprises a fluid connection A from the evaporator 2 allowing the entry of the refrigerant in the vapor state into the absorber 3, preferably directly. The absorber 3 comprises a fluid connection C, D, E with the generator 4, more precisely to a second economizer 16 through which the working solution called rich from the absorber 3 is heated before being transmitted to the generator 4. Then, the working solution, called rich, leaving the absorber 3 in the direction of the generator 4, leaves the second economizer 16 and then passes, preferably, through an expansion valve 9 before reaching the generator 4. Advantageously, the second economizer 16 is an exchanger transmitting heat from the solution, called lean, coming from the generator 4 to the solution, called rich, coming from the absorber 3.The second economizer 16 allows energy recovery to reduce the size of the absorber 3 and the generator 4 and thus significantly improve the performance of the transformer 1. Advantageously, the generator 4 comprises a fluid connection H, G, F, with the absorber 3, more precisely. with a solution pump 8. The fluid connection allows the entry of the working solution, called lean, from the generator 4 into the absorber 3, preferably, through the pump 8 then the second economizer 16. In the absorber 3, the phase change of the refrigerant from the vapor state to the liquid state is accompanied by a release of heat which is transmitted to a source to be heated. It is this production of heat at the absorber 3 which is particularly sought after according to the invention. The heat source produced by the absorber 3, producing the heated source 14 can be, according to one possibility, directly used in particular in industry. The temperature of the heated source 14 at the outlet of the absorber 3 is advantageously at least 80°C, preferably 100°C, or even 120°C.

[0082] The fluid circuit comprises a fluid connection A ensuring the fluid connection of the evaporator 2 to the absorber 3, preferably directly, more precisely from the outlet 21 of the evaporator 2 to the inlet 30 of the absorber 3. The fluid connection A ensures the circulation of at least part of the flow of refrigerant fluid in the gaseous state and at a first pressure corresponding to a high pressure from the evaporator 2 to the absorber 3.

[0083] The fluid circuit comprises a fluid bypass B ensuring the fluid connection of the evaporator 2 to the ejector 6, preferably directly, more precisely from the outlet 21 of the evaporator 2, or from the fluid connection A, to the primary fluid inlet 60 of the ejector 6. The fluid bypass B ensures the circulation of at least a portion of the flow of refrigerant fluid in the gaseous state and at a second pressure corresponding to a high pressure from the evaporator 2 to the ejector 6.

[0084] The fluid circuit comprises a fluid connection C ensuring the fluid connection of the absorber 3 to the second economizer 16, preferably directly, more precisely from the outlet 31 of the absorber 3 to the inlet of the second economizer 16. The fluid connection C ensures the circulation of the flow of a working solution, called rich, and at a third pressure corresponding to a high pressure from the absorber 3 towards the generator 4.

[0085] The fluid circuit comprises a fluid connection D ensuring the fluid connection of the second economizer 16, preferably directly, to a pressure reducer 9. The fluid connection D ensures the circulation of the flow of the so-called rich working solution, cooled after its passage through the second economizer 16 and at a fourth pressure corresponding to a high pressure from the second economizer 16 towards the generator 4.

[0086] The fluid circuit comprises a fluid connection E ensuring the fluid connection of the regulator 9, preferably directly, to the generator 4, plus precisely towards the inlet 40 of the generator 4. The fluid connection E ensures the circulation of the flow of the heated rich working solution and at a fifth pressure corresponding to a low pressure from the regulator 9 towards the generator 4.

[0087] The regulator 9 ensures a reduction in the pressure of the flow of the rich working solution before it enters the generator 4.

[0088] The fluid circuit comprises a fluid connection F ensuring the fluid connection of the generator 4, more precisely the outlet 42 of the generator 4, preferably directly, to a solution pump 8. The fluid connection F ensures the circulation of the flow of the lean working solution and at a sixth pressure corresponding to a low pressure from the generator 4 towards the absorber 3.

[0089] The fluid circuit comprises a fluid connection G ensuring the fluid connection of the solution pump 8, preferably directly, to the second economizer 16. The fluid connection G ensures the circulation of the flow of the lean working solution and at a seventh pressure corresponding to a high pressure from the solution pump 8 towards the absorber 3.

[0090] The solution pump 8 ensures compression of the working solution and therefore an increase in the pressure of the flow of the lean working solution before it enters the absorber 3.

[0091] The fluid circuit comprises a fluid connection H ensuring the fluid connection of the second economizer 16, preferably directly, to the absorber 3. The fluid connection H ensures the circulation of the flow of the lean and heated working solution after its passage through the second economizer 16 and at an eighth pressure corresponding to a high pressure from the second economizer 16 to the absorber 3.

[0092] The fluid circuit comprises a fluid connection I ensuring the fluid connection of the generator 4, more precisely of the outlet 41 of the generator 4, preferably directly to the ejector 6, more precisely the secondary fluid inlet 61 of the ejector 6. The fluid connection I ensures the circulation of the flow of the refrigerant fluid in the gaseous state and at a ninth pressure corresponding to a low pressure, coming from the generator 3 to the ejector 6.

[0093] The fluid circuit comprises a fluid connection J ensuring the fluid connection of the ejector 6, more precisely of the outlet 62 of the mixture, to the condenser 5, preferably directly to the first economizer 15. The fluid connection J ensures the circulation of the flow of refrigerant fluid in the gaseous state and at a tenth pressure corresponding to an intermediate pressure, coming from the ejector 6 to the first economizer 15 in the direction of the condenser 5.

[0094] The ejector 6 ensures a mixture of a primary fluid corresponding to at least a portion of the flow of refrigerant in the gaseous state at the second pressure corresponding to a high pressure coming from the evaporator 2 and the flow, preferably its entirety, of refrigerant in the gaseous state at a ninth pressure corresponding to a low pressure, coming from the generator 3 so as to produce a flow of refrigerant in the gaseous state and at a tenth pressure corresponding to an intermediate pressure. The ejector 6 makes it possible to introduce a third pressure level into the fluid circuit.

[0095] The fluid circuit comprises a fluid connection K ensuring the fluid connection of the first economizer 15, preferably directly to the condenser 5, more precisely the inlet 50 of the condenser 5. The fluid connection K ensures the circulation of the flow of the refrigerant fluid in the cooled gaseous state after its passage through the first economizer 15 and at an eleventh pressure corresponding to an intermediate pressure, coming from the ejector 6 to the condenser 5.

[0096] The fluid circuit comprises a fluid connection L ensuring the fluid connection of the condenser 5, more precisely the outlet 51 of the condenser 5, preferably directly to a pump 7, in the direction of the evaporator 2. The fluid connection L ensures the circulation of the flow of refrigerant fluid in the liquid state and at a twelfth pressure corresponding to an intermediate pressure, coming from the condenser 5 towards the pump 7.

[0097] The fluid circuit comprises a fluid connection M ensuring the fluid connection of the pump 7 to the evaporator 2 and preferably passing through the first economizer 15. The fluid connection M ensures the circulation of the refrigerant fluid in the liquid state and at a thirteenth pressure corresponding to a high pressure, coming from the pump 7 towards the first economizer 15.

[0098] The pump 7 ensures compression of the refrigerant fluid in the liquid state and therefore an increase in the pressure of the flow of refrigerant fluid in the liquid state before it enters the evaporator 2.

[0099] The fluid circuit comprises a fluid connection N ensuring the fluid connection of the first economizer 15 to the evaporator 2, preferably directly and more precisely to the inlet 20 of the evaporator 2. The fluid connection N ensures the circulation of the refrigerant fluid in the heated liquid state after its passage through the first economizer 15 and at a fourteenth pressure corresponding to a high pressure coming from the first economizer 15 towards the evaporator 2.

[0100] The pressures: first, second, third, fourth, seventh, eighth, seventeenth may or may not be identical but all correspond to high pressures.

[0101] The pressures: fifth, sixth, ninth, may or may not be identical but all correspond to low pressures.

[0102] The pressures: tenth, eleventh, twelfth and sixteenth may or may not be identical but all correspond to intermediate pressures.

[0103] Example: Evaluation of the performance of a TCA according to the invention in summer conditions.

[0104] The ejector performance was chosen using the experimental results for an ammonia ejector reported by Sankarlal and Mani T, “Experimental investigations on ejector refrigeration system with ammonia,” Renew. Energy, vol. 32, no. 8, pp. 1403-1413, 2007, doi: 10.1016 / j.renene.2006.05.008.

[0105] The parameters retained are: • a drive ratio of 0.3, a compression ratio of 1.8 and an expansion ratio of 3; • an average temperature of the heat source 10 and of the heat source 11, being fatal heat to be recovered, of 80°C; • a temperature of the source to be heated at the inlet of the absorber of 100°C; • the outside temperature is 35°C, the ambient air is used as a source cold 13 thus presenting a temperature of 35°C.

[0106] Simple TCA (state of the art without ejector): COP_th=0.20 COP_elec=2.6 AT_abs=0.4°C

[0107] TCA according to [Fig. 1] COP_th=0.18 COP_elec=38 AT_abs=ll.2°C

[0108] The results of this test show that the use of a perfect ejector 6 makes it possible to improve the COP_elec of the machine by a factor of 20 (in the TCA configuration, only electrical energy is a source of expenditure) and the COP_th from 0.2 to 0.18. The most important point to note is the temperature difference of the source to be heated between the inlet and the outlet of absorber 3, AT_abs, which goes from 0.4 to 11°C. This is the most important factor in justifying the use of an ejector in the TCA because this temperature difference dictates the possibility or not of valorizing the hot source by a new industrial process. A difference of 0.4°C is not sufficient to supply an industrial process while a difference of 11°C can supply many industrial processes or heat networks.

[0109] List of references 1. Heat transformer 2. Evaporator 3. Absorber 4. Generator 5. Condenser 6. Ejector 7. Pump 8. Solution pump 9. Regulator 10. Evaporator hot spring 11. Generator hot spring 13. Condenser cold source 14. Heated spring 15. Saver 16. Saver 20. Inlet into the evaporator 21. Evaporator outlet 30. Entry into the absorber 31. Absorber outlet 32. Second inlet into the absorber 40. Input into the generator 41. Generator output 42. Second Generator Output 50. Entry into the first condenser 51. Condenser outlet 60. Primary fluid inlet 61. Secondary fluid inlet 62. Mix output 70. Entry into the pump 71. Pump outlet 80. Inlet into the solution pump 81. Solution pump outlet 90. Entry into the regulator 91. Regulator outlet

Claims

Claims

1. Absorption heat transformer (1), intended for the production of high temperature heat, comprising a fluid circuit receiving a working solution formed of a refrigerant / absorbent couple and successively comprising in fluid connection: an evaporator (2) operating at high pressure, an absorber (3) operating at high pressure and intended for the production of high temperature heat, a generator (4) operating at low pressure and a condenser (5), the fluid circuit comprises a pump (7) arranged between the condenser (5) and the evaporator (2), a solution pump (8) arranged between the generator (4) and the absorber (3), and an expansion valve (9) arranged in parallel with the solution pump (8) between the absorber (3) and the generator (4), characterized in that the transformer (1) comprises, arranged on the fluid circuit, an ejector (6) placed between the generator (4) and the condenser (5), and a fluid bypass (B) arranged,between the evaporator (2) and the ejector (6), in bypass of a fluid connection (A) connecting the evaporator (2) to the absorber (3), and the ejector (6) comprises a primary fluid inlet (60) at high pressure in fluid connection with the evaporator (2) by the fluid bypass (B), a secondary fluid inlet (61) at low pressure in fluid connection with an outlet (41) of the generator (4) and a mixing outlet (62) at intermediate pressure in fluid connection with an inlet (51) of the condenser (5), the condenser (5) operating at intermediate pressure.,

2. Transformer according to the preceding claim in which the refrigerant / absorbent couple forming the working solution is ammonia / water (NH3 / H2O).

3. Transformer according to any one of the preceding claims comprising at least one control member arranged on the fluid circuit at the junction between the fluid bypass (B) and the fluid connection (A) and a control unit configured to control the control member so as to ensure the distribution of the refrigerant towards the absorber (3) and / or the ejector (6).

4. A method of producing high temperature heat by an absorption heat transformer (1) according to any preceding claim comprising circulating a flow of working solution formed by a refrigerant / absorbent pair and a flow of refrigerant in the fluid circuit, characterized in that it comprises the production of heat at the absorber (3) and the primary fluid inlet (60) of the ejector (6) is supplied by at least part of a flow of refrigerant in the gaseous state and at high pressure coming from the evaporator (2) and that the secondary fluid inlet (61) of the ejector (6) is supplied by the entire flow of refrigerant in the gaseous state and at low pressure coming from the generator (4) and that the ejector (6) produces a mixture of refrigerant at intermediate pressure leaving through the mixture outlet (62) in fluid connection with the condenser (5) operating at intermediate pressure.

5. Method according to the preceding claim in which the pump (7) ensures the increase in the pressure of the flow of refrigerant in the liquid state and at intermediate pressure coming from the condenser (5) up to a high pressure.

6. Method according to any one of the two preceding claims in which at least one control member arranged on the fluid circuit at the junction of the fluid bypass (B) and the fluid connection (A) and a control unit configured to control the control member ensures the regulation of the flow of refrigerant coming from the evaporator and transmitted to the ejector (6) and of the flow of refrigerant coming from the evaporator and transmitted to the absorber (3).

7. Method according to any one of the three preceding claims in which the condenser (5) comprises a cold source (13) intended to ensure cooling within the condenser (5), the cold source (13) being at a maximum temperature less than or equal to 45°C.

8. Method according to the preceding claim in which the cold source (13) is ambient air.

9. A method according to any one of the five preceding claims wherein the low pressure is lower than the medium pressure which is itself lower than the high pressure.

10. A method according to any one of the six preceding claims wherein the low pressure is less than or equal to 900 KPa, the high pressure is greater than or equal to 2500 KPa and the intermediate pressure is greater than 1000 KPa and less than 2000 KPa.

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