Reversible thermodynamic machine for the production of electricity and high-temperature heat

Abstract

Reversible thermodynamic machine for the production of electricity and heat at high temperature. The invention relates to a reversible thermodynamic machine for the production of electricity and heat comprising a first circuit for the production of heat, successively connecting a first heat exchanger (1) operating as a generator, then a first phase separation tank (6) fluidically connected in parallel to a reversible compressor (3) operating as a compressor and to a solution pump (4), a second heat exchanger (2) operating as an absorber, then to a second phase separation tank (7), then to an expansion valve (5), then to the first heat exchanger (1), and a second compression circuit for the production of electricity, successively connecting the first heat exchanger (1) operating as an absorber,the first phase separation tank (6), then the solution pump (4), then the second heat exchanger (2) operating as a generator, then the second phase separation tank (7), then in parallel the reversible compressor (3) operating as an expansion device and the expansion valve (5) fluidly connected to the first heat exchanger (1). Figure for the abbreviation: Fig. 1,

Description

Title of the invention: Reversible thermodynamic machine for the production of electricity and high-temperature heat technical field

[0001] The invention relates to the field of thermodynamic systems for the production of electrical and thermal energy. It finds particularly advantageous application in the field of stationary systems using low-temperature heat sources such as waste heat from industrial processes, solar thermal, biomass, geothermal, and gas turbines. STATE OF THE ART

[0002] The societal challenges concerning the recovery of waste heat are becoming increasingly significant. Waste heat, with a temperature between 70°C and 95°C, for example from industrial processes, is a heat source that must be recovered to enable the decarbonized production of electricity or industrial heat, which is typically above 100°C.

[0003] Heat production systems such as conventional heat pumps that use waste energy to produce heat at a higher temperature are already known.

[0004] Absorption Heat Transformer (AHT) machines for the production of High Temperature Heat are also known.

[0005] Kalina cycles for the production of electricity by absorption machines are also known.

[0006] However, to ensure optimal recovery of waste heat, it is sought to have flexible conversion systems with reversible operation of compact and efficient machines.

[0007] There is therefore a need to propose a solution that achieves all or part of these objectives. SUMMARY

[0008] To achieve this objective, according to one embodiment, a reversible thermodynamic machine for the production of electricity and heat is provided, comprising: - a first heat exchanger configured to operate alternately as a generator or as an absorber, - a second heat exchanger configured to operate alternately as an absorber or as a generator, - a reversible compressor configured to operate alternately as a compressor or as an expansion device, - advantageously a solution pump, - advantageously a pressure relief valve. Typically, a reversible thermodynamic machine comprises: - a first phase separation tank, - a second phase separation tank, - a first circuit for heat production, preferably directly connecting the first heat exchanger operating as a generator, then the first phase separation tank, which is fluidly connected in parallel to the reversible compressor operating as a compressor and to the solution pump. The reversible compressor and the solution pump are fluidly connected to the second heat exchanger operating as an absorber, then to the second phase separation tank, then to the expansion valve, and finally to the first heat exchanger operating as a generator. - a second compression circuit intended for the production of electricity, connecting fluidically, preferably directly, successively the first heat exchanger operating as an absorber, the first phase separation tank, then the solution pump, then the second heat exchanger operating as a generator, then the second phase separation tank, then in parallel the reversible compressor operating as an expansion device and the expansion valve, the expansion valve and the reversible compressor operating as an expansion device being fluidically connected to the first heat exchanger operating as an absorber.

[0009] The thermodynamic machine according to the invention allows, thanks to a simple architecture, in a first configuration the production of thermal energy of the heat type, advantageously at temperature and in a second configuration the production of electricity from waste thermal energy.

[0010] The use of a reversible compressor in an absorption cycle is an unusual approach for those skilled in the art, who would encounter problems related to the refrigerant in the compressor in expander mode. The compressor is thus adapted to operate alternately as an expander connected to a generator for electricity production and as a compressor driven by a motor to compress a fluid.

[0011] The reversible compressor is arranged between the generator and the absorber.

[0012] The addition of phase separation tanks allows this reversible compressor and solution pump to be used without damage and with optimum efficiency.

[0013] Advantageously, the working solution comprises ammonia (NH3) as the refrigerant and H2O as the absorbent. Preferably, the working solution is not an organic fluid. In our view, the invention relates to a method for producing electricity and heat from a reversible thermodynamic machine as described above, comprising - a heat production phase by circulating a working solution in the first heat production circuit comprising: • the production of low-pressure ammonia vapor by the first heat exchanger operating as a generator through heat exchange with the first heat source, • the separation in the first phase separation tank of the two-phase working solution from the first heat exchanger operating as a steam generator, transmitted to the reversible compressor operating as a compressor, and of the ammonia-lean solution transmitted to the solution pump, • the increase in steam pressure by the reversible compressor and the increase in lean solution pressure by the solution pump, • the mixing of high-pressure steam and high-pressure lean solution, • heating the source to be heated by the second heat exchanger operating as an absorber, generating heat by exothermic reaction of the high-pressure steam mixture and high-pressure lean solution towards the source to be heated; and advantageously alternately - A phase of electricity production by circulating a working solution in the second electricity production circuit comprising: • the production of low-pressure ammonia vapor by the second heat exchanger operating as a generator through heat exchange with the second heat source, • the separation in the second phase separation tank of the working solution from the second heat exchanger operating as a steam generator transmitted to reversible compressor operating as a pressure-reducing device and in a low-ammonia solution transmitted to the pressure-reducing valve, • the expansion of high-pressure steam by the reversible compressor operating as an expansion device, • the production of electricity by a turbine connected to the reversible compressor operating as an expansion device, • the mixture of low-pressure steam from the reversible compressor operating as an expansion device and the lean solution from the expansion valve, • the rejection of heat by the first heat exchanger operating as an absorber generating heat by exothermic reaction of the mixture of low pressure vapor and low pressure lean solution towards a cold source, the rich working solution from the first heat exchanger operating as an absorber is transmitted to the solution pump. BRIEF DESCRIPTION OF THE FIGURES

[0014] The aims, objects, features and advantages of the invention will become clearer from the detailed description of an embodiment thereof, which is illustrated by the following accompanying drawings in which:

[0015] [Fig. 1] The [Fig. 1] represents the reversible thermodynamic machine according to the invention in heat production mode by the first fluidic circuit.

[0016] [Fig.2] Fig.2 represents the reversible thermodynamic machine according to the invention in electricity production mode by the second fluidic circuit.

[0017] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily to scale with practical applications. DETAILED DESCRIPTION

[0018] Before proceeding with a detailed review of embodiments of the invention, optional features that may be used in combination or alternatively are listed below:

[0019] According to one example, the reversible thermodynamic machine includes a working solution formed by the ammonia / water (NH3 / H2O) couple and suitable for circulating in the first heat production circuit and in the second electricity production circuit.

[0020] According to one example, the reversible thermodynamic machine comprises a first heat source (8) circulating in the first heat exchanger (1) operating as a generator, a heat source (9) circulating in the second heat exchanger (2) operating as an absorber, a cold source (11) circulating in the first heat exchanger (1) operating as an absorber, and a second heat source (10) circulating in the second heat exchanger (2) operating as a generator

[0021] According to one example, the first heat source (8) and the second heat source (10) may be identical and be a fatal heat source.

[0022] According to one example, the reversible thermodynamic machine includes a generator associated with the reversible compressor (3) operating as an expansion device for the production of electricity.

[0023] The upstream and downstream, the inlet, the outlet, at a given point are taken in reference to the direction of fluid flow.

[0024] A parameter "approximately equal to / greater than / less than" or "of the order of" a given value means that this parameter is equal to / greater than / less than the given value, to within 10% or even 5% of that value.

[0025] For the purposes of this disclosure, the expression "A and / or B" means (A), (B) or (A and B). For the purposes of this disclosure, the expression "A, B and / or C" means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).

[0026] Fluidically connected or in fluidic connection means when a line provides a connection by or in which a fluid flows.

[0027] In this description, the expression "A fluidly connected to B" is synonymous with "A is in fluidic connection with B" and does not necessarily mean that there is no component between A and B. The expressions "arranged on" or "on" are synonymous with "fluidly connected to".

[0028] Thus, these expressions refer to a fluidic connection between two elements, this connection being either direct or indirect. This means that it is possible for a fluid to flow between a first element and a second element that are fluidically connected, through one or more conduits, cavities, or channels, possibly including an additional component. Hot, cold, and cooled refer to a relative temperature with respect to another point in the system.

[0029] Conversely, the term "fluidically connected directly" refers to a direct fluidic connection between two elements. This means that between a first element and a second element that are fluidically connected directly, no other element is present, other than a conduit or several conduits.

[0030] The terms "first", "second" and "third", "additional" etc. are used simply as labels, and are not intended to impose numerical requirements on their objects.

[0031] The invention relates to a reversible thermodynamic machine for the production of electricity and heat. A thermodynamic machine is understood to be an absorption machine.

[0032] An absorption chiller is a thermodynamic system with thermal "compression" using refrigerant / sorbent pairs with strong affinities to replace the vapor compression of traditional machines. This solution offers low electrical consumption, as the main energy source comes from the heat source, thus limiting operating costs when utilizing a low-cost energy source such as gas, or a free one (such as solar energy or waste heat). Furthermore, the refrigerants used in absorption chillers have no environmental impact: neither on global warming potential (GWP = 0) nor on the ozone layer (ODP = 0).

[0033] This type of device operates thanks to the ability of certain liquids to absorb (exothermic reaction) and desorb (endothermic reaction) a vapor. It also utilizes the fact that the solubility of this vapor in the liquid depends on temperature and pressure. Thus, these devices use a binary mixture as their working solution, one component of which is more volatile than the other and constitutes the refrigerant.

[0034] The thermodynamic machine according to the invention comprises the combination of components from an absorption machine and a compression machine.

[0035] The thermodynamic machine comprises a first heat exchanger 1 configured to operate alternately as a generator or as an absorber and a second heat exchanger 2 configured to operate alternately as an absorber or as a generator. Advantageously, the first heat exchanger 1 and the second heat exchanger 2 play the complementary roles of generator and absorber, respectively, namely, for example, the role of generator and absorber respectively, or alternately of absorber and generator.

[0036] The thermodynamic machine also includes a reversible compressor 3 configured to operate alternately as a compressor or as an expander, also called an expansion device.

[0037] According to the invention, the thermodynamic machine advantageously comprises a first phase separation tank 6 and a second phase separation tank 7.

[0038] The thermodynamic machine advantageously comprises a solution pump 4 and an expansion valve 5.

[0039] According to an embodiment not shown, the thermodynamic machine includes an economizer.

[0040] To improve the performance of the machine, other secondary exchangers such as a rectifier or a subcooler can also be integrated into the thermodynamic machine.

[0041] According to the invention, the thermodynamic machine comprises a working solution of refrigerant / absorbent fluid comprising, in one possibility, the ammonia / water (NH3 / H2O) pair. The concentrations of the refrigerant and the absorbent in the working solution are adapted to the operating pressure and temperature of the thermodynamic machine.

[0042] This NH3 / H2O couple is suitable for air conditioning, refrigeration, and heating applications. Crystallization is not possible within the operating pressure and temperature ranges. However, for this couple, the vapor pressure difference between the absorbent and the refrigerant is small. Consequently, traces of water are carried along with the ammonia vapor at the outlet of the first heat exchanger 1 operating as a generator or of the second heat exchanger 2 operating as a generator.

[0043] According to the invention, the thermodynamic machine comprises a first separation tank 6 arranged directly downstream of the first heat exchanger 1 and a second separation tank 7 arranged directly downstream of the second heat exchanger 2. According to an embodiment not illustrated, the thermodynamic machine may comprise a rectifier arranged downstream of one or both of the heat exchangers 1,2.

[0044] The working solution is said to be rich, because the concentration of refrigerant is greater than in the so-called lean working solution.

[0045] The thermodynamic machine according to the invention is described below and in particular the fluidic connections of the different components.

[0046] The system according to the invention comprises a first heat exchanger 1 operating alternately as a generator and as an absorber.

[0047] The first heat exchanger 1 is fluidly connected to the expansion valve 5 by a fluid connection I and to the first phase separation tank 6 by a fluid connection A. More specifically, the first heat exchanger 1 comprises an inlet fluidly connected to the outlet of the expansion valve 5 and an outlet fluidly connected to the inlet of the first phase separation tank 6.

[0048] The first heat exchanger 1 includes an inlet and an outlet of a source 8 intended to ensure heat exchange with the working solution circulating in the first heat exchanger 1.

[0049] The source is either a first heat source 8, when the first heat exchanger 1 operates as a generator, or a cold source 11, when the first heat exchanger 1 operates as an absorber.

[0050] In the case where the first heat exchanger 1 operates as a generator, corresponding to a first configuration or embodiment intended for the production of heat advantageously at high temperature, it is configured to vaporize the refrigerant of the working solution by heat exchange with a first heat source 8. The first heat source 8 is advantageously a waste heat source. By way of preferred example, the first heat source 8 has a temperature between 60°C and 95°C.

[0051] In the case where the first heat exchanger 1 functions as an absorber, corresponding to a second configuration or embodiment intended for electricity production, it is configured to mix and absorb the refrigerant vapor in the lean solution by rejecting heat to a cold source 11 such as ambient air. By way of preferred example, the cold source 11 has a temperature between 10°C and 30°C.

[0052] The first phase separation tank 6 is arranged at the outlet, i.e. downstream, of the first heat exchanger 1.

[0053] The first phase separation tank 6 is fluidically connected to the first heat exchanger 1 by the fluidic connection A. More specifically, the inlet of the first phase separation tank 6 is fluidly connected to the outlet of the first heat exchanger 1 by the Fluidic connection A.

[0054] The first phase separation tank 6 is fluidically connected to the solution pump 4 by a fluid connection D. Specifically, a first outlet of the first phase separation tank 6 is fluidly connected to the inlet of the solution pump 4 by the fluid connection D. Advantageously, the outlet of the first phase separation tank 6 connected to the solution pump 4 is the outlet of the working solution in liquid phase.

[0055] The first phase separation tank 6 is fluidically connected to the reversible compressor 3 by a fluid connection B. More specifically, a second outlet of the first phase separation tank 6 is fluidly connected to the inlet of the reversible compressor 3 by the fluid connection B. Advantageously, the second outlet of the first phase separation tank 6 connected to the reversible compressor 3 is the outlet of the working solution in the vapor phase.

[0056] The role of the first phase separation tank 6 is to separate the refrigerant vapor from the lean solution. This phase separation ensures that the refrigerant vapor can be processed by the reversible compressor 3 without risk of damage and that the lean solution can be efficiently treated by the solution pump 4.

[0057] This phase separation by the first phase separation tank 6 is implemented more particularly when the first heat exchanger 1 operates as a generator, i.e. the thermodynamic machine operates in the first configuration, i.e. following the heat production fluidic circuit.

[0058] The reversible compressor 3 is configured to operate alternately as a motor-driven compressor or as an expander, also called a pressure-reducing device, driving a generator.

[0059] The reversible compressor 3 is fluidically connected to the first separation tank 6 and to the second heat exchanger 2. The reversible compressor 3 is fluidly connected to the first separation tank 6, more precisely to a second outlet, by a fluid connection B allowing the entry of the refrigerant in the vapor state into the reversible compressor 3.

[0060] The reversible compressor 3 is fluidly connected to the second heat exchanger 2 by a fluid connection C, advantageously continuing as a fluid connection F. More precisely, an outlet of the reversible compressor 3 is fluidly connected to the inlet of the second heat exchanger 2

[0061] The reversible compressor is fluidly connected to the second phase separation tank 7 by a fluid connection J. More specifically, an inlet of the reversible compressor 3 is fluidly connected to an outlet of the second phase separation tank 7 by the fluid connection J. Advantageously, the outlet of the second phase separation tank 7 allows the circulation of refrigerant vapor to the reversible compressor 3.

[0062] According to one possibility, an economizer can be arranged at the interface of the fluidic connections H and E so as to optimize heat exchange.

[0063] According to a preferred option, the reversible compressor 3 is a positive displacement machine advantageously combined with an electric motor or generator. More precisely, the positive displacement machine is a positive displacement compressor of the piston, scroll, or screw type, depending on the desired power output.

[0064] According to one possibility, the reversible compressor is a turbomachine type compressor.

[0065] According to one possibility, the reversible compressor 3 is mechanically connected to the solution pump 4 of the solution loop so as to supply it with energy directly.

[0066] The reversible compressor 3 in compressor mode is powered by a motor supplying a power PELEC> i n- In this mode, corresponding to the first In the embodiment or first configuration intended for heat production, the reversible compressor 3 has the function of compressing the refrigerant, more precisely refrigerant vapor, passing through it so as to increase its pressure at the inlet of the second heat exchanger 2 operating as an absorber.

[0067] The reversible compressor 3 in expander mode is connected to a generator. In this mode, corresponding to the second embodiment or second configuration intended for electricity production, the reversible compressor 3 in expander mode expands the refrigerant, more precisely the refrigerant vapor, passing through it, transforming thermal energy into mechanical energy. The generator transforms the mechanical energy recovered by the expander into electricity, producing electrical power PELEC> o ut-

[0068] The solution pump 4 is fluidly connected to the first heat exchanger 1 by a fluid connection D and to the second heat exchanger 2 by a fluid connection E advantageously continuing into a fluid connection F. More specifically, an outlet of the solution pump 4 is fluidly connected to the inlet of the second heat exchanger 2. The solution pump 4 is intended to compress and increase the pressure of the working solution in the liquid phase, either the lean solution in the case of operation following the heat production fluid circuit, or the rich solution in the case of operation following the electricity production fluid circuit.

[0069] The second heat exchanger 2 is fluidly connected to the reversible compressor 3 by the fluid connection C extending into fluid connection F, to the solution pump 4 by the fluid connection E extending into fluid connection F, and to the second phase separation tank 7 by the fluid connection G. More specifically, the second heat exchanger 2 comprises an inlet fluidly connected to the outlet of the reversible compressor 3 and to the outlet of the solution pump 4 and an outlet fluidly connected to the inlet of the second phase separation tank 7.

[0070] The second heat exchanger 2 includes an inlet and an outlet of a source intended to ensure heat exchange with the working solution circulating in the second heat exchanger 2.

[0071] The source is either a source to be heated 9 when the second heat exchanger 2 operates as an absorber, or a second heat source 10 when the second heat exchanger 2 operates as a generator.

[0072] In the case where the second heat exchanger 2 operates as an absorber, it is configured to mix and absorb the refrigerant vapor in the lean solution by rejecting heat to a source to be heated 9. As For example, the source to be heated 9 has a temperature greater than 90 °C and preferably greater than 100 °C so as to allow the production of very high temperature heat, i.e. greater than 100 °C.

[0073] In the case where the second heat exchanger 2 operates as a generator, it is configured to vaporize the refrigerant of the working solution by heat exchange with a second heat source 10. The second heat source 10 is advantageously a waste heat source and may be identical to the first heat source 8. As a preferred example, the second heat source 10 has a temperature greater than 90°, preferably greater than 100°, preferably in the order of 120°C.

[0074] The second phase separation tank 7 is arranged at the outlet, i.e. downstream, of the second heat exchanger 2.

[0075] The second phase separation tank 7 is fluidically connected to the second heat exchanger 2 by the fluid connection G. More specifically, the inlet of the second phase separation tank 7 is fluidly connected to the outlet of the second heat exchanger 2 by the fluid connection G.

[0076] The second phase separation tank 7 is fluidly connected to the expansion valve 5 by a fluid connection H. More specifically, a first outlet of the second phase separation tank 7 is fluidly connected to the inlet of the expansion valve 5 by the fluid connection H. Advantageously, the outlet of the second phase separation tank 7 connected to the expansion valve 5 is the outlet of the working solution in liquid phase.

[0077] The second phase separation tank 7 is fluidly connected to the reversible compressor 3 by a fluid connection J. More specifically, a second outlet of the second phase separation tank 7 is fluidly connected to the inlet of the reversible compressor 3 by the fluid connection J. Advantageously, the second outlet of the second phase separation tank 7 connected to the reversible compressor 3 is the outlet of the working solution in the vapor phase.

[0078] The role of the second phase separation tank 7 is to separate the refrigerant vapor from the lean solution. This phase separation ensures that the refrigerant vapor can be processed by the reversible compressor 3 without risk of damage and that the lean solution can be efficiently treated by the expansion valve 5.

[0079] This phase separation by the second phase separation tank 7 is implemented more particularly when the second heat exchanger 2 operates as a generator, i.e. the thermodynamic machine operates according to the fluidic circuit of electricity production.

[0080] Advantageously, the system includes an expansion valve 5 arranged between the second phase separation tank 7 and the first heat exchanger 1. More specifically, an inlet of the expansion valve 5 is fluidically connected to the outlet of the second phase separation tank 7 by the fluid connection H and the outlet of the expansion valve 5 is fluidly connected to the inlet of the first heat exchanger 1 by the fluid connection I. The expansion valve 5 is configured to expand the refrigerant in the liquid state from the second phase separation tank 7.

[0081] The thermodynamic machine according to the invention operates at two temperature levels: an intermediate temperature level corresponding to the condensation temperature of the refrigerant, but also to the absorption temperature of the refrigerant by the absorber, and a high temperature level corresponding to the driving temperature of the generator.

[0082] The thermodynamic machine according to the invention operates partly at high pressure between the outlet of the pump 4 and the outlet of the reversible compressor 3 and the inlet of the expansion valve 5, and partly at low pressure between the outlet of the expansion valve 5, and the inlet of the pump 9 and the inlet of the reversible compressor 3.

[0083] This thermodynamic cycle is feasible because the vapor pressure difference between the absorbent and the refrigerant varies with temperature and pressure. This variability allows for a concentration difference between the lean and rich solutions, as described below.

[0084] The thermodynamic machine according to the invention comprises a first fluidic circuit, referred to as the heat production circuit, configured to ensure the fluidic connection of the various components of the thermodynamic machine and the circulation of the working solution so as to ensure the production of heat, advantageously very high-temperature heat. Very high-temperature heat is understood to mean a temperature above 100 °C. The first fluidic circuit is a closed circuit intended to receive the working solution.

[0085] The thermodynamic machine according to the invention comprises a second fluidic circuit, referred to as the electrical production circuit, configured to ensure the fluidic connection of the various components of the thermodynamic machine and the circulation of the working solution so as to ensure the production of electricity. The second fluidic circuit is a closed circuit intended to receive the working solution.

[0086] The first fluidic circuit and the second fluidic circuit are at least partially common.

[0087] The thermodynamic machine according to the invention comprises, in one possibility, a module for managing the circulation of the working solution. The management module is configured to define the machine's operating conditions based on energy requirements and fluctuations in energy sources.

[0088] The management module includes, in particular, control valves and / or at least the expansion valve 5 advantageously whose opening is adjustable and / or means for adjusting the flow rates of the working solution and the refrigerant, in particular by controlling the speed of the solution pump 4. The thermodynamic machine comprising the management module according to the invention has the advantage of being compact, advantageously requiring only a few additional components such as valves, possibly temperature and pressure sensors, which reduces costs and size, allowing the integration of the thermodynamic machine according to the invention into mobile applications.

[0089] The thermodynamic machine is configured to operate alternately in at least two operating modes. The thermodynamic machine is configured to take alternately at least two configurations.

[0090] The thermodynamic machine produces either thermal energy or electrical energy. Thermal energy is considered to be the production of heat.

[0091] According to the first operating mode, corresponding to a first configuration, the thermodynamic machine is configured to ensure the circulation of the working solution in the first heat production fluid circuit. In this first configuration, the first fluid circuit provides the fluid connection of the components detailed above. The first fluid circuit provides the fluid connection from the first heat exchanger 1, advantageously operating as a generator, to the first phase separation tank 6. Then, the first fluid circuit provides the fluid connection from the phase separation tank 6 to the reversible compressor 3 and the solution pump 4 in parallel. Then, the first fluid circuit provides the fluid connection from the reversible compressor 3 and the solution pump 4 in parallel to the second heat exchanger 2, advantageously operating as an absorber.Then, the first fluid circuit ensures the fluid connection from the second heat exchanger 2, advantageously operating as an absorber, to the second phase separation tank 7. Then, the first fluid circuit ensures the fluid connection from the second phase separation tank 7 to the expansion valve 5. Then, the first fluid circuit ensures the fluid connection from the expansion valve 5 to the first heat exchanger 1, advantageously operating as a generator.

[0092] The operation of the system according to [Fig. 1] is described below. In this first configuration, allowing operation according to the first operating mode, the working solution circulates in the first fluidic circuit of heat production, the first heat exchanger 1 operates as generator 1 and the second heat exchanger 2 operates as absorber 2.

[0093] In this mode of operation, the thermodynamic machine operates in a heat pump type mode.

[0094] The first heat exchanger 1, operating as a generator, produces refrigerant vapor, advantageously ammonia, at low pressure by heat exchange with a first heat source 8. The fluid exiting the first heat exchanger 1 through fluid connection A is two-phase; traces of water are carried along with the ammonia vapor and liquid water. The two-phase fluid, consisting of liquid and vapor phases, enters the first phase separation tank 6 to be separated into a liquid phase and a vapor phase. The vapor phase, i.e., the refrigerant vapor, in this case ammonia, exits the first phase separation tank 6 through fluid connection B, which feeds the inlet of the reversible compressor 3. The refrigerant vapor is compressed by the reversible compressor 3, which operates as a compressor.The refrigerant vapor exits the reversible compressor 3 at a higher pressure than the pressure at which it entered the compressor. This high-pressure refrigerant vapor exits the compressor 3 through fluid connection C. Simultaneously, the liquid phase of the working solution, i.e., the lean solution (in this case, water), exits the first phase separation tank 6 through fluid connection D, which feeds the inlet of the solution pump 4. The lean solution is compressed by the solution pump 4 and exits at a higher pressure than the pressure at which it entered. This high-pressure lean solution exits the solution pump 4 through fluid connection E.The high-pressure refrigerant vapor circulating in fluid connection C and the high-pressure lean solution circulating in fluid connection E are mixed either in a fluid connection F or directly in the second heat exchanger 2, which operates as an absorber. The second heat exchanger 2, operating as an absorber, is supplied with the mixture of the high-pressure refrigerant vapor and the high-pressure lean solution, advantageously via a fluid connection F. In the second heat exchanger 2, operating as an absorber, the absorption of the refrigerant vapor into the lean solution produces an exothermic reaction, ensuring heat rejection to a heat source 9 circulating within the second heat exchanger 2. The high-pressure working solution exits the second heat exchanger 2, operating as an absorber, via the fluid connection G.The fluidic connection G supplies the second phase separation tank 7. In this operating mode, the second separation tank 7 does not need. To ensure phase separation, the working solution exiting the second heat exchanger 2, operating as an absorber, is single-phase and in the liquid state. In one scenario, the second phase tank could be bypassed by a connecting branch. The high-pressure working solution passes through the second phase separation tank 7 without any change in temperature, pressure, or state, and exits through the fluid connection H, which supplies the pressure relief valve 5. The high-pressure working solution exits the pressure relief valve 5 at a lower pressure than it entered. The low-pressure working solution exits the pressure relief valve 5 through the fluid connection that supplies the inlet of the first heat exchanger 1, operating as a generator.The low-pressure working solution can then be vaporized by the generator, thus closing a complete cycle of the first fluidic heat production circuit.

[0095] According to the second operating mode, corresponding to a second configuration, the thermodynamic machine is configured to ensure the circulation of the working solution, including the second fluid circuit for electricity production. In this second configuration, the second fluid circuit provides the fluid connection of the components detailed above. The second fluid circuit provides the fluid connection from the first heat exchanger 1, operating as an absorber, to the first phase separation tank 6. Then, the second fluid circuit provides the fluid connection from the first phase separation tank 6 to the solution pump 4. Finally, the second fluid circuit provides the fluid connection from the solution pump to the second heat exchanger 2, operating as a generator.Then, the fluid circuit provides the fluid connection from the second heat exchanger 2, operating as a generator, to the second phase separation tank 7. Next, the second fluid circuit provides the fluid connection from the second phase separation tank 7 in parallel to the reversible compressor 3, operating as an expander, and to the expansion valve 5. Then, the second fluid circuit provides the fluid connection from the reversible compressor 3, operating as an expander, to the inlet of the first heat exchanger, operating as an absorber. In parallel, the second fluid circuit provides the fluid connection from the expansion valve 5 to the inlet of the first heat exchanger 1, operating as an absorber.

[0096] The operation of the system according to [Fig.2] and described below.

[0097] In this second configuration, allowing operation according to the second mode of operation, the working solution circulates in the second fluidic circuit for electricity production, the first heat exchanger 1 operates as a generator and the second heat exchanger 2 operates as an absorber.

[0098] The second heat exchanger 2 operates as a generator, producing high-pressure refrigerant vapor, advantageously ammonia, by heat exchange with a second heat source 10. The fluid exiting the second heat exchanger 1 through the fluid connection G is two-phase; traces of water are carried along with the ammonia vapor and liquid water. The two-phase fluid, formed by the liquid and vapor phases, enters the second phase separation tank 7 to be separated into a liquid phase and a vapor phase. The vapor phase, i.e., the refrigerant vapor, in this case ammonia, exits the second phase separation tank 7 through the fluid connection J, supplying the inlet of the reversible compressor 3, which operates as an expander.The refrigerant vapor is expanded by the reversible compressor 3, which operates as an expander connected to a generator, thus producing electricity. The refrigerant vapor exits the reversible compressor 3 at a lower pressure than the pressure at which it entered the compressor. This low-pressure refrigerant vapor exits the compressor 3 through fluid connection K. Simultaneously, the liquid phase of the working solution, i.e., the lean solution (in this case, water), exits the second phase separation tank 7 through fluid connection H, feeding the inlet of the expansion valve 5. The lean solution is expanded by the expansion valve 5 and exits at a lower pressure than the pressure at which it entered. This low-pressure lean solution exits the expansion valve 5 through fluid connection I.The low-pressure refrigerant vapor circulating in fluid connection K and the low-pressure lean solution circulating in fluid connection I are mixed either in a fluid connection L or directly in the first heat exchanger 1 operating as an absorber. The first heat exchanger 1 operating as an absorber is supplied with the mixture of the low-pressure refrigerant vapor and the low-pressure lean solution, advantageously via a fluid connection L. In the first heat exchanger 1 operating as an absorber, the absorption of the refrigerant vapor into the lean solution produces an exothermic reaction, resulting in heat rejection to a cold source 11 circulating within the first heat exchanger 1. The low-pressure working solution exits the first heat exchanger operating as an absorber via the fluid connection A.Fluid connection A supplies the first phase separation tank 6. In this operating mode, the first phase separation tank 6 does not need to perform phase separation, as the working solution exiting the first heat exchanger 2, operating as an absorber, is single-phase and in the liquid state. According to one possibility, the first phase tank 6 could be... avoided by a bypass branch. / The low-pressure working solution passes through the first phase separation tank 6, without any change in temperature, pressure, or state, and exits through the fluid connection D, which supplies the solution pump 4. The low-pressure working solution exits the solution pump 4 at a higher pressure than it entered. The high-pressure working solution exits the solution pump 4 through the fluid connection E, which supplies the inlet of the second heat exchanger 2, operating as a generator. The high-pressure working solution can then be vaporized by the generator, thus completing a full cycle of the electricity generation fluid circuit.

[0099] In the first mode of operation, the demand for heat production can be checked by the management module according to a binary command, i.e. a non-zero heat production value meaning a demand for heat production and a zero heat production value meaning an absence of demand for heat production.

[0100] In the case of a demand for heat production, advantageously high temperature for example above 100 °C, in particular from a waste heat source at a temperature for example between 70 °C and 95 °C which may be fluctuating, the working solution circulation management module will define a working solution circulation of the heat pump type as illustrated in [Fig.1].

[0101] In the second operating mode, the demand for electricity production can be checked by the management module according to a binary command, i.e., a non-zero electricity production value meaning a demand for electricity production and a zero electricity production value meaning an absence of demand for electricity production.

[0102] In the case of a demand for electricity production, particularly from a heat source such as waste heat, for example, ranging between 70 °C and 150 °C and potentially fluctuating, the working solution circulation management module will define a working solution circulation as illustrated in [Fig. 2]. The working solution circulation cycle is similar to a Rankine cycle, more specifically to a Kalina cycle.

[0103] According to one possibility, the management module is advantageously configured to switch the thermodynamic machine from a first configuration to the second configuration and vice versa based on economic criteria. For example, when electricity is cheap, the thermodynamic machine is in the first heat production configuration, heat pump mode, and when electricity is expensive, it is in the second electricity production configuration.

[0104] According to one embodiment, the system comprises at least one electricity storage module associated with the reversible compressor 3 and, more specifically, with the electric generator associated with the reversible compressor 3. Electricity storage thus allows energy storage when the source and the demand are not simultaneous. For example, electric batteries are provided.

[0105] Example 1:

[0106] A detailed configuration example is provided below.

[0107] First configuration - first embodiment - fluidic circuit for heat production - Heat pump mode ([Fig. 1]) Component Typical configuration Generator: Inlet temperature: 75°C Absorber: Target heat temperature at the absorber outlet: 120°C Pump: Flow rate: 340 kg / h, Efficiency: 80% Reversible compressor: Compression ratio: 3.75, High pressure: 32 bar, Low pressure: 8.5 bar

[0108] Applying the following assumptions: Temperature pinch with external sources within the exchangers AT_pinch=5°C Efficiency of the internal heat exchanger(s): q_ech=0.8 Overall pump / compressor efficiency: q_conversion = q_elec * q_meca = 0.9 * 0.8 Isentropic compressor efficiency: qcompi - 0.8

[0109] We obtain: Thermal power produced at the absorber: 130 kW Thermal power to be supplied to the generator: 89 kW Compressor power consumption: 41 kW Pump power consumption: 2.6 kW Electrical coefficient of performance: COP e / ec = 3.15

[0110] Second configuration - second embodiment - fluidic circuit for electricity production - ([Fig.2])

[0111] A detailed configuration example is provided below.

[0112] First configuration - first embodiment - fluidic circuit for heat production - Heat pump mode ([Fig. 1]) Component Typical configuration Generator: Inlet temperature: 100°C Absorber: Cooling temperature: 25°C Pump: Flow rate: 2500 kg / h, Efficiency: 80% Expansion valve: Isentropic efficiency: 73%

[0113] By an order-of-magnitude calculation, the following results are obtained: The thermal power to be supplied to the generator: 310 kW The thermal power of the cooling at the absorber: 297 kW The mechanical power produced by the expansion device is around 10 kW for an exegetical efficiency of 23%.

[0114] The invention is not limited to the embodiments previously described and extends to all embodiments covered by the invention.

[0115] List of references 1. First heat exchanger 2. Second heat exchanger 3. Reversible compressor 4. Solution pump 5. Pressure relief valve 6. First separation tank 7. Second separation tank 8. First source of heat 9. Heat source 10. Second source of heat 11. Cold source A. Fluid connection between the outlet of the first heat exchanger 1 and the inlet of the first separation tank 6 B. Fluidic connection between the steam outlet of the first separation tank 6 and the inlet to the reversible compressor 3 C. Fluid connection between the high-pressure steam outlet of the reversible compressor 3 and the inlet fluid connection of the second heat exchanger 2 D. Fluidic connection between the outlet 2 of the first separation tank 6 (lean solutions) and the inlet of the solution pump 4 E. Fluid connection between the low-pressure solution outlet of solution pump 4 and the inlet fluid connection of the second heat exchanger 2 F. Fluidic inlet connection of the second heat exchanger 2 G. Fluidic connection between the outlet of the second heat exchanger and the second separation tank 7 H. Fluidic connection between the rich solution outlet of the second reservoir separation 7 and the inlet of the pressure relief valve 5 I. Fluidic connection between the outlet of the pressure-reducing valve 5 and the inlet of the first heat exchanger 1 J. Fluidic connection between the high-pressure Rich vapor outlet of the second separation tank 7 and the inlet of the reversible compressor as an expansion device 3 K. Physical connection between the outlet of the reversible compressor as expansion member 3 and the fluidic connection I connected to the inlet of the first heat exchanger 1.

Claims

1. Demands Reversible thermodynamic machine for the production of electricity and heat comprising: - a first heat exchanger (1) configured to operate alternately as a generator or as an absorber, - a second heat exchanger (2) configured to operate alternately as an absorber or as a generator, - a reversible compressor (3) configured to operate alternately as a compressor or as an expansion device, - a solution pump (4), - a pressure relief valve (5), characterized in that it includes - a first phase separation tank (6), - a second phase separation tank (7), - a first circuit for heat production, successively connecting the first heat exchanger (1) operating as a generator, then the first phase separation tank (6) fluidically connected in parallel to the reversible compressor (3) operating as a compressor and to the solution pump (4), the reversible compressor (3) and the solution pump (4) being fluidly connected to the second heat exchanger (2) operating as an absorber, then to the second phase separation tank (7) then to the expansion valve (5), then to the first heat exchanger (1) operating as a generator, - a second compression circuit for electricity production, successively connecting the first heat exchanger (1) operating as an absorber, the first phase separation tank (6), then the solution pump (4), and finally the second heat exchanger (2) operating as that generator, then the second phase separation tank (7), then in parallel the reversible compressor (3) operating as an expansion element and the expansion valve (5), the expansion valve (5) and the reversible compressor (3) operating as an expansion element being fluidly connected to the first heat exchanger (1) operating as an absorber.

2. Reversible thermodynamic machine according to claim 1 comprising a working solution formed by the ammonia / water (NH3 / H2O) couple and suitable for circulating in the first heat production circuit and in the second electricity production circuit.

3. A reversible thermodynamic machine according to any one of the two preceding claims, comprising a first heat source (8) circulating in the first heat exchanger (1) operating as a generator, a heat source (9) circulating in the second heat exchanger (2) operating as an absorber, a cold source (11) circulating in the first heat exchanger (1) operating as an absorber, and a second heat source (10) circulating in the second heat exchanger (2) operating as a generator

4. Reversible thermodynamic machine according to the preceding claim in which the first heat source (8) and the second heat source (10) can be identical and be a waste heat source.

5. Reversible thermodynamic machine according to any one of the preceding claims comprising a generator associated with the reversible compressor (3) operating as an expansion device for the production of electricity.

6. A method for producing electricity and heat from a reversible thermodynamic machine according to any one of the preceding claims, comprising - a heat production phase by circulating a working solution in the first heat production circuit comprising: • the production of low-pressure ammonia vapor by the first heat exchanger (1) operating as a generator by heat exchange with the first heat source (8), • the separation in the first phase separation tank (6) of the two-phase working solution from the first heat exchanger (1) operating as a steam generator transmitted to the reversible compressor (3) operating as a compressor and of the ammonia-lean solution transmitted to the solution pump (4), • the increase in steam pressure by the reversible compressor (3) and in the pressure of the lean solution by the solution pump (4), • the mixing of high-pressure steam and high-pressure lean solution, • heating of the source to be heated (9) by the second heat exchanger (2) operating as an absorber generating heat by exothermic reaction of the high-pressure steam mixture and high-pressure lean solution towards the source to be heated (9); a phase of electricity production by circulating a working solution in the second electricity production circuit comprising: • the production of low-pressure ammonia vapor by the second heat exchanger (2) operating as a generator by heat exchange with the second heat source (10), • the separation in the second phase separation tank (7) of the working solution from the second heat exchanger (2) operating as a steam generator transmitted to the reversible compressor (3) operating as an expansion unit and in ammonia-poor solution transmitted to the pressure relief valve (5), the expansion of high-pressure steam by the reversible compressor (3) operating as an expansion device, the production of electricity by a turbine connected to the reversible compressor (3) operating as an expansion device, the mixing of the low-pressure steam from the reversible compressor (3) operating as an expansion device and the lean solution from the expansion valve (5), the heat rejection by the first heat exchanger (1) operating as an absorber generating heat by exothermic reaction of the mixture of low pressure steam and low pressure lean solution towards a cold source (11), the rich working solution from the first heat exchanger (1) operating as an absorber is transmitted to the solution pump (4).

Images