Integrated hermetic device for combined heat and power arrangements

Abstract

An integrated hermetic device for Combined Heat and Power (CHP) energy generation arrangements, such as Heller- type thermal cycles, which integrates within a hermetic and sealed module in a vertical and aligned manner at least one vapor expander, an electric generator, a direct contact condenser and at least one pump, arranged in conjunction with a volume compensator vessel and flow control arrangement, providing this device with innovative and advantageous features in terms of costs, ease of installation and maintenance, and operational simplicity, while not requiring extra lubricating agents in the bearings, operating only with the same working fluid, whereby the tightness of the internal conduits is no longer critical. This integration enables working in thermodynamic vacuum conditions without exposing the rest of the installation to such condition, minimizing the possibility of non- condensable gases ingress, such as air, and avoiding the working fluid losses to the environment.

Description

[0001]INTEGRATED HERMETIC DEVICE FOR COMBINED HEAT AND POWER ARRANGEMENTS CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of Argentine patent application no. 20230102799, filed 19 October 2023, which is hereby incorporated by reference as though fully set forth herein. BACKGROUND Field The present disclosure relates to methods and / or devices used in Combined Heat and Power (CHP) energy generation systems employing thermal cycles similar to the Rankine cycle, and more particularly refers to a novel compact and hermetic device that integrates components of this thermal cycle (e.g., vapor expander, electric generator, condenser, pump, flow control), providing this device with innovative and advantageous features not only in terms of cost or ease of installation and maintenance, but also in terms of operational simplicity. This integration, based on confinement within a single hermetic container, enables working in thermodynamic vacuum conditions without exposing the rest of the installation to such conditions, minimizing the possibility of non-condensable gases ingress, such as air, and avoiding working fluid losses to the environment. The present teachings can be applied in, but are not limited to, the fields of: • Household and industrial combined heat and power systems from fossil fuels, biogas or biomass, geothermal energy sources or others. • On / Off-grid electric power generation from fossil fuels, biogas or biomass, geothermal energy sources or others. • Distributed electric power generation from fossil fuels, biogas or biomass, geothermal energy sources or others. • Electric power generation from waste heat recovery. Description of related art The Rankine cycle is the representative power cycle of the thermodynamic process that takes place in a conventional thermoelectric plant, normally operating with water as the working fluid. The Rankine cycle typically includes a series of devices or equipment connected in such a way that the working fluid is capable of circulating in a closed circuit: Pump, Steam Generator, Expander and Condenser. The working fluid that leaves the condenser in the liquid phase is driven by the pump to a steam generator, normally a steam boiler, which operates at a higher pressure than the condenser, where the fluid is vaporized using inlet heat from an external source. The vaporized working fluid then is expanded by reducing its pressure to condenser pressure in an expander, usually a turbine, to finally return to liquid phase in the condenser where it delivers its residual energy to a heat sink, usually a river or ambient air, thus closing the thermal cycle. When the steam expands, it delivers useful work to the expander, which is capable of transmitting such mechanical work to an associated electric generator that converts it into electrical energy. Most conventional thermoelectric plants that use the steam Rankine cycle require a secondary cooling circuit to carry out the heat that leaves the cycle in the condenser to a cold source or heat sink. These secondary systems normally operate with water in liquid phase and require an extra pumping system, a cooling tower in case of cooling with air, or water treatment systems in case of cooling with rivers or lakes. In addition to electric power generation, another widespread application of the Rankine-type thermal cycle is known as a cogeneration system or a combined heat and power generation system, in which the virtues of the Rankine cycle are advantageously applied to generate both electric power energy and thermal energy. In these cogeneration systems, thermal energy that leaves the cycle, instead of being directed to the heat sink, is used in another application, normally for heating. This additional thermal energy is achieved by taking full or partial advantage of the heat that comes out of the cycle when working fluid condenses in the condenser. Applying a Rankine cycle in this configuration achieves greater use of the heat provided by a thermal source to the cycle, in addition to eliminating the requirement for a secondary cooling circuit as mentioned before. Common applications of water Rankine cycle cogeneration systems include those in which the thermal energy leaving the cycle is used for industrial heating or district heating, usually through secondary steam pipes. Another application in which these cogeneration systems have been well accepted is in non-conventional energy generation facilities, such as geothermal, solar or biomass facilities. The ability of these cogeneration systems to adapt to distributed or off-grid energy generation systems is a general interest. Finally, an interesting application of this type of system is the waste heat recovery from another process, for example, exhaust gases from engines or industrial furnaces. In this type of system, the hot source that provides heat or energy to the steam generator is a liquid or gaseous stream with residual energy that leaves another process. If this residual energy is not used, it would be lost to the environment, so the objective of this type of cogeneration system is to recover this residual energy and convert it into electrical energy through a Rankine cycle. One of the most widespread configurations of the Rankine cycle in cogeneration systems application is known as the Organic Rankine Cycle (ORC). In this configuration, the working fluid is an organic fluid: hydrocarbons, refrigerant fluids (HFCs, HFOs), siloxanes, among others. These types of fluids exhibit a series of properties that make them favorable, compared to water, from a thermodynamic and / or operational point of view. The final working fluid selection depends on the requirements for a particular application. Some of the properties that make organic fluids interesting may be: low critical temperature, reduced vaporization heat, reduced thermal gradient, possibility of operating at condenser pressures higher than atmospheric, among others, which contribute to enhancing the cycle´s performance under certain conditions. Most ORC cycles present a distinctive feature in the equipment configuration that differentiates them with respect to the conventional Rankine cycle mentioned above, namely, a heat exchanger, commonly called a regenerator, is added to the cycle, to exchange heat between the hot expanded vapor stream that leaves the turbine and the cold liquid condensed stream that is driven by the pump prior to entering the vapor generator. In this way, part of the residual energy of the vapor is used to preheat the fluid that enters the boiler or vapor generator, substantially increasing the thermodynamic performance of the system. However, because organic working fluids may degrade with temperature, most cogeneration systems in which the heat source is a boiler based on the combustion of a fuel agent (gas, LPG, oil, biomass) require an intermediate heat transport circuit with oils or thermal fluids that ensure that the organic working fluid is not exposed to the high temperatures of combustion gases. These intermediate heating circuits operate in closed loop in a single liquid phase and require additional equipment or components, such as: pumps, heat exchanger, control systems, among others. A particular configuration for a Rankine cycle that does not require a secondary refrigeration circuit to remove heat from the cycle is what is known in the industry as dry air cooling or Heller system, in honor of its inventor (see United States patent no. 2,356,404). This system has the virtue of being able to cool the cycle, or remove heat from the cycle, with an air current at room temperature, which circulates by natural or forced draft, and exchanges heat directly with the working fluid, without the need for a secondary circuit. Thanks to a variation in the configuration of the equipment respect to a conventional Rankine cycle, the cooling of the working fluid can be carried out at higher pressures than atmospheric, avoiding exposing equipment, components and pipes to vacuum conditions or pressure below atmospheric, which could favor the entry of non-condensable gases into the circuit, deteriorating the performance. This particular cycle configuration involves changing the conventional surface contact condenser to what is known in the industry as a direct contact condenser (DCC). In this condenser type, the incoming vapor gets into direct contact with a cold liquid stream of working fluid that is capable of absorbing the vapor energy and condensing it at equilibrium temperature that is the result of the thermodynamic balance between both streams. In a conventional Rankine cycle that uses water as working fluid, in order to obtain the highest possible performance, the condenser normally operates at temperatures below 50ºC, which makes the operating pressure (equilibrium pressure) in the condenser of any Rankine cycle to be below atmospheric pressure, around 100 mbar, exposing parts of the installation to vacuum. The development of the Heller system was designed precisely to work with water as the working fluid, where the DCC works under atmospheric pressure, but thanks to an adequate pumping system that takes the condensed water from the bottom of the condenser and achieves recirculation at pressures higher than atmospheric. The liquid water that leaves the condensate accumulator at condensation temperature is divided into two streams, a small portion is sent to the boiler or steam generator by means of a pump that raises the fluid pressure to the boiler pressure, and the other portion is sent by a second pump, recirculation pump, to the water-air exchanger for cooling, the heat output of the cycle. The Heller system is compatible for development of cogeneration systems or equipment, since it allows the use of water as a working fluid, eliminating the problem of organic fluid degradation caused by exposure to direct combustion boilers, eliminating an intermediate heat transport circuit, in addition to being a low-cost substance that may also be desirable from operational and / or environmental standpoints. Another feature that this system offers is the possibility to cool directly with air. The use of a direct contact condenser (DCC) adds an additional advantage to the installation, because it allows the equipment size to be reduced compared to a conventional condenser thanks to increased thermodynamic efficiency resulting from direct contact of the phases. In this type of condenser, the thermal performance and therefore the equipment size is proportional to the dispersion of one phase with respect to the other. Because, under typical operating conditions, the volume of expanded steam leaving the expander can be up to about 100 times greater than the volume of cold liquid water, it is necessary to disperse adequately the liquid phase to increase the contact area of the phases. This can be achieved by passing the liquid phase through a diffuser, which is a device with holes or nozzles that distributes uniformly a liquid fluid over a surface in the form of fine droplets. Although, as mentioned above, the phase dispersion helps reduce the size of the equipment, it is possible to further reduce its size with the addition of a suitable vapor-liquid contact medium that increases contact time between phases, such as described in United States patent no. 5,925,291. Working with these two variables, phase dispersion and contact time, it is possible to improve the thermal performance of the direct contact condenser and therefore reduce its size. Every condenser, regardless of type, requires an accumulation area that holds the condensed liquid and prevents the escape of vapor from the condenser towards the pump. Most of this equipment operates with a volume of accumulated condensate that must be kept above a minimum level, which is achieved with different types of level control systems. Changes in the liquid level at the condenser bottom are primarily due to changes in temperature and condensation pressure that result in the expansion or contraction of the working fluid within a closed cycle, changes in the circulation flow, among others. One way to achieve level control in the condensate accumulator in a direct contact condenser, in a passive manner, can be as mentioned in United States patent no. 1,564,223, where a floating device is associated with a valve on the cold liquid working fluid inlet line of the condenser. Level changes related to working fluid volume variations due to temperature effects are passively compensated by imposing a restriction or increasing the fluid inflow rate into the condenser. An external vessel, at atmospheric pressure, serves as a compensator for these volume changes, absorbing or supplying the necessary amount of liquid. An active level control system, which not only controls the condenser liquid level but also the circulation flow rate, can be achieved by implementing two pumps, one upstream the cold liquid water inflow into the condenser and the other at condenser outflow, as carried out in United States patent application publication no. 2018 / 0051595. Controlling the flow rate of cold water entering the condenser allows for the regulation of the condensation temperature as well as the condensation pressure (at thermodynamic equilibrium with the temperature) with the objective of operating the steam expander at the most favorable operating point. Having a second pump (pump 2) at condensate outlet allows the condenser liquid level to be maintained within the appropriate range, liquid levels that are monitored through appropriate sensors. The versatility of this active control system requires, on the other hand, a series of sensors and actuators suitable for its operation, such as: electronic speed variators for the pumps, inlet and outlet flow sensors to the condenser, level sensors inside the condenser, temperature sensors and a temperature and level integrated control system. On the other hand, the seals and losses problems of the working fluid, and its contamination with lubricating fluids associated with the integral rotary shaft that couples the electric generator with the steam expander, are known. For example, in United States patent application publication no. 2008 / 0252077, the use of bearings that do not require lubrication, such as magnetic bearings, allowed the consolidation of a single sealed container that contains the steam expander and the electric generator associated with the same rotary shaft, where it only has one inlet for hot steam coming from the boiler or steam generator, and one outlet for expanded steam that is directed to the condenser, without using another type of lubricating fluid within the system. Other solutions that have been studied or applied seeking the same goal are the use of ceramic bearings that do not require lubrication, or the use of bearings that can be lubricated by the same working fluid such as hybrid bearings or hydrodynamic bearings, typically used in refrigeration system compressors. This sealed assembly arrangement of vapor expander and electric generator requires solving the cooling of the electric generator, which in this case, is incapable of dissipating heat directly to the atmosphere. This is the subject, for example, of United States patent application publication no. 2015 / 0184546, which solves the problem for an ORC system, where the electric generator is cooled by the working fluid in the vapor phase, with vapor that after leaving the expander is cooled in the regenerator and before entering the condenser takes the heat from the electric generator. Although the Rankine cycle has been widely used in the related art, it would be desirable to have new arrangements that allow improvements in performance and cycle operation, while minimizing related manufacturing costs. Likewise, it is widely known that extant arrangements are large, covering large physical spaces, and as a result require a high number of connection and sealing accessories to prevent leaks or unwanted entry of gases into the assembly. It would therefore be desirable to minimize or even eliminate seals and connections under vacuum conditions that allow reducing the entry of non-condensable gases into the system, simplifying its operation, with the reduction in number and size of hermetic and sealed containers that make up the system, such as the shell or carcass of heat exchangers, connection pipes and other containment, would save space and reduce manufacturing and assembly costs. Likewise, the simplification and reduction of the number of control systems, with their corresponding sensors and actuators, would allow both to reduce costs and simplify the system operation. BRIEF DESCRIPTION It is therefore an object of the disclosure to provide an integrated hermetic device that integrates within a hermetic and sealed module in a vertical and aligned manner the equipment that makes up a Heller-type Rankine thermal cycle (vapor expander, electric generator, condenser, circulation pump and flow control). It is yet another object of the disclosure to provide an integrated hermetic device that significantly simplifies the embodiment in order to optimize physical spaces and reduce related costs. It is yet another object of the disclosure to provide an integrated device that, by not requiring additional lubricating agents in the bearings, the equipment operates with a single fluid (the working fluid), where the tightness of internal conduits is not critical. It is also another object of the disclosure to provide an integrated hermetic device that, by providing an integration of the parts added to a good confinement within a single hermetic and sealed module or container, allows working in vacuum thermodynamic conditions without the need for exposing the rest of the installation to such a condition and minimizing the possibility of losses to the environment or the entry of non-condensable gases into it. It is yet another object of the disclosure to provide a vertical and aligned arrangement of the components in a single confinement structure, being a cylindrical structure, completely hermetic and sealed, with connection flanges between the sections and free of mechanical seals and external movable parts. It is yet another object of the disclosure to provide an integrated and sealed device that can be used in the fields of: Home and industrial cogeneration systems (heat and power systems); Generation of electrical energy in network or isolated; Distributed generation of low power electrical energy; and / or Waste heat recovery. It is also another object of the disclosure to provide an integrated hermetic device for heat and power cogeneration arrangements, such as Heller-type thermal cycles, wherein the device includes a hermetic and sealed module or container that has at least one main fluid feed inlet and at least one main fluid discharge outlet, said hermetic and sealed module or container being provided internally in a vertical and descending manner with: a) at least one expansion section of said fluid in a vaporized state entering through said main feed inlet; b) at least one condensation section of said fluid in an expanded state exiting through said first expansion section, wherein said condensation section in turn includes: at least one secondary feed inlet for said fluid in liquid state, at least one valve to control the fluid flow entering through said secondary feed inlet, at least one device for spraying the fluid passing through the control valve adjacent to said secondary fluid feed inlet, and at least one phase contact medium arranged below the spraying device; and c) at least one accumulation section of condensed fluid through said condensation section, wherein said accumulation section includes: a space for accumulation of a volume of condensed fluid, at least one floating element operatively connected to said control valve through a stem, at least one circulation pump being in communication with said main fluid discharge outlet. BRIEF DESCRIPTION OF THE DRAWINGS For greater clarity and understanding of the object of the present disclosure, it has been illustrated in several figures, in which the disclosure has been represented in one or more embodiments by way of example, where: Figure 1 shows a schematic cross-sectional view of the integrated hermetic device for cogeneration systems according to a first embodiment of the disclosure; Figure 2 shows a diagram of a Heller-type Rankine thermal cycle in which the device of Figure 1 is found in accordance with the disclosure; Figure 3 shows another scheme focused on the operation of the device of Figure 1 in accordance with the disclosure, where a set of valves is used to control the flow of the device of Figure 1; Figure 4 shows a diagram focused on the operation of a second embodiment of the disclosure, where a positive displacement pump is used to control the flow of the device of Figure 1; Figure 5 shows a schematic view of a third embodiment of the disclosure, where a pump is provided outside the hermetic and sealed module of the invention; Figure 6 shows a schematic view of a fourth embodiment of the disclosure, where a second pump is provided in connection with the lower discharge of the hermetic and sealed module of the invention; Figure 7 shows a schematic view of a fifth embodiment of the disclosure, where a regenerator or heat exchanger is provided in a condensation section; and Figure 8 shows a schematic view of a Heller cycle, where the arrangement illustrated in Figure 7 is used in accordance with the present disclosure, in combination with a positive displacement pump for flow control of the device. DETAILED DESCRIPTION Referring now to the figures, the disclosure relates to a new compact and hermetic device which integrates several of the equipment that make up a Heller-type Rankine Cycle (vapor expander, electric generator, direct contact condenser, pump, and flow control system), providing this device with innovative and advantageous features not only in terms of construction simplicity and reduced installation costs, but also in terms of simplicity of operation thanks to an integrated flow control system, and the hermetic characteristics that the equipment presents. This component integration within a single hermetic and sealed module or container allows working in vacuum thermodynamic conditions without the need to expose the rest of the installation to such condition, minimizing the possibility of non- condensable gases inlet, such as air. According to Figures 1 to 3, in a first embodiment, the instant disclosure provides a novel integrated hermetic device which is used in a variant of the Rankine-type thermal cycle, better known as a Heller System and which is indicated by the general reference 1. Device 1 includes a hermetic and sealed module or container 2 which has at least one main feed inlet 3 connected to a vapor generator 4 through respective tubes or pipes 5, and at least one main discharge outlet 6 arranged in the lower part thereof. Within said hermetic and sealed module 2, all the elements or devices that make up this particular thermal cycle are integrated and assembled in a vertical arrangement. This cutting-edge integration of the elements will reduce the number of vessels subjected to external or internal pressure, connections, pipes, instrumentation and control systems, optimizing the physical space of the thermal circuit with a consequent reduction in installation costs. Likewise, the device design of the instant disclosure will allow relevant parts to be lubricated and cooled with the same working fluid without the need to incorporate specific lubricants or other types of fluids. The hermetic and sealed module or container 2 is sealed in all its joints and connections, and due to the operating thermodynamic conditions, the majority of said connections are at pressures above atmospheric, looking to avoid the air ingress or the fluid leaks that could harm the process and / or the components’ lifespans. Advantageously, according to the instant teachings, tubes and pipes are no longer sealing critical points. Referring again to said hermetic and sealed module or container 2, it includes at least one expansion section 7 of a fluid in a vapor state coming from the vapor generator 4 and entering through said main feed inlet 3. Expansion section 7 presents firstly a vapor expander 8 arranged downstream of, and in communication with said main feed inlet 3, and at least one electric generator 9 arranged downstream of, and connected by an integrated rotary shaft with vapor expander 8. In vapor expander 8, the expansion of the incoming working fluid occurs in a vapor state, this vapor, being dry or wet, delivers mechanical work to the integral shaft and consequently drives the rotor of the electric generator 9 for the generation of electric energy. It should be noted that vapor expander 8 can be turbine type (radial and / or axial) or positive displacement type (piston, screw, vanes, rotary, etc.). The rotor of the vapor expander 8 has a bearing arrangement without the need of lubricants or capable of being lubricated by the same working fluid, which is advantageous from operational and / or cost perspectives because it minimizes or avoids the use of extra lubricants that may contaminate the working fluid. On its part, electric generator 9 may include a compact radial or axial magnetic flux generator, capable of operating in contact with the working fluid and using it as a cooling source. Likewise, immediately downstream of expansion section 7 and in fluid communication with it, there is a condensation section 10 of the low pressure expanded fluid exiting from expansion section 7. To carry out the condensation, condensation section 10 includes a phase contact medium 11, which in the upper part of it there is at least one secondary upper feed inlet 12 of cold working fluid or “cold fluid” or “refrigerant fluid”. The cold fluid, passing through the flow meter 13, comes from the cycle refrigeration system, a system that may be composed of a fluid-air heat exchanger 14, which receives the hot condensed working fluid from the main discharge outlet 6, thus closing the cooling or refrigeration circuit of the cycle. The fluid that enters through the secondary feed inlet 12 is the same working fluid and is referred to as cold or refrigeration fluid because it is at a lower temperature than the vaporized fluid coming from the vapor generator. It should be noted that secondary upper feed inlet 12 is connected to flow meter 13 through a respective tube / pipe 15; flow meter 13 is connected to fluid-air heat exchanger 14 through a tube / pipe 16; while fluid-air heat exchanger 14 is connected to main discharge outlet 6 through a tube / pipe 17, as best illustrated in Figure 2. To carry out the condensation of the vapor, at least one spraying device 18 is provided that includes a plurality of sprays for the cold fluid that enters through the secondary feed inlet 12. Spraying device 18 can uniformly disperse the cold fluid, improving contact with the expanded vapor. In this way, the cold fluid coming from the fluid-air heat exchanger 14 – flow meter 13, enters through the secondary upper feed inlet 12, passes through a control valve 21 and is ejected through the spraying device 18 in order to come into contact with the low pressure expanded vapor coming from the expansion section 7 and begin the condensation process. To promote condensation of the low pressure expanded vapor, contact medium 11 is provided for phase contact along whose length the condensation process occurs with direct contact between the expanded vapor phase and the cold liquid phase of the working fluid. The disclosure also includes at least one accumulation section 19 where the fluid condensed in the previous stage remains accumulated. Accumulation section 19 includes at least one floating element 20 operatively connected to control valve 21, which, according to some aspects of the disclosure, may be a needle type valve, and which allows the flow rate control of the incoming cold fluid through secondary upper inlet feed 12. Likewise, in accumulation section 19, a circulation pump 23 is provided downstream of floating element 20, being entirely submerged in the condensed fluid accumulated in accumulation section 19. Circulation pump 23 suctions the condensed fluid from the accumulation section 19 and discharges it towards the main discharge outlet 6 in order to drive it back into the cycle through the corresponding pipe 34. As represented in Figure 2, a portion of the hot condensed fluid drifts towards the vapor generator 4 through the respective pipe 24 via a flow regulator 36 provided on said pipe 24, while the remaining hot condensed fluid is pumping to the fluid-air heat exchanger 14, through the respective pipe 17, in order to be cooled in said heat exchanger and then returned, through the upper secondary feed inlet 12, again to the hermetic and sealed module 2. On the other hand, the flow control valve 21 acts on the cold working fluid, which enters the hermetic and sealed module 2 through the secondary upper feed inlet 12, coming from the flow meter 13 and connected upstream of the spraying device 18. The pressure drop experienced by the fluid when passing through flow control valve 21 ensures that the upstream installation remains at pressures higher than atmospheric, allowing the condensation section 10 to operate at pressures lower than atmospheric. Flow control valve 21 can be of the needle type, though other types of linear displacement valves can be utilized without departing from the scope of the present disclosure, such as: globe, gate, diaphragm, among others. Floating element 20, which may be cylindrical in shape, is located suspended or floating above the condensate accumulation section 19 and is rigidly linked to the plug of the flow control valve 21 via a stem 35 that longitudinally passes through the phase contact medium 11. An internal conduit of the phase contact medium 11 acts as a guide for stem 35, allowing its movement only in a vertical direction and limiting the possibility of buckling. Thus, the closure degree of the flow control needle valve 21 is linked to the vertical position of the floating element 20. It should be noted that, in order to facilitate the understanding of the instant disclosure and improve clarity of the figures, the foregoing guide for stem 35 of floating element 20 is not illustrated. The flooding degree of the floating element 20 within the accumulation section 19 causes a proportional buoyant force that, once its own weight has been overcome, produces its upward vertical displacement and consequently the displacement of the plug of the flow control valve 21 in the same direction, causing the gradual closure of the latter. The closing of the flow control valve 21 generates, furthermore, a downward hydrodynamic force on its plug, as a result of the pressure difference that the fluid experiences when passing through the effective flow area of flow control valve 21, which is partially reduced by the valve plug. This floating element 20 - flow control valve 21 assembly continues moving upward until the buoyant force and the hydrodynamic force, from opposite directions, are balanced. In this way, a subsequent increase in the liquid level in the accumulation section 19 causes a rise of the floating element 20 – flow control valve 21 assembly, reaching a new balance point of these forces in which the flow control valve 21 is proportionally more closed, thus decreasing the inlet flow rate of cold liquid working fluid to the condensation section 10. Similarly, a decrease in the liquid level in the accumulation section 19 causes a decrease of the assembly, which result in a partial opening of the flow control valve 21 with the consequent increase in inlet flow rate to the condensation section 10. As illustrated in Figure 3, a control arrangement including, in certain aspects of the disclosure, a first upper solenoid valve 26, with full open / closed operation, is connected to the hermetic and sealed module 2 in the accumulation section 19. Likewise, the control arrangement can include a second lower solenoid valve 27, of similar construction and operation to the upper solenoid valve 26, connected to the pipe 34 or "discharge line" of the circulation pump 23. Both solenoid valves 26-27 are connected downstream to a common pipe 33 that communicates with a volume compensator vessel 25 at atmospheric pressure, which is sealed to the atmosphere by an elastic membrane to prevent the entry of air. It should be noted that first upper solenoid valve 26 is connected to a secondary lower feed inlet 28 provided in a lower portion of the hermetic and sealed module 2, corresponding to the location of accumulation section 19, being connected by a tube / pipe 29. Likewise, first upper solenoid valve 26 is connected to volume compensator vessel 25 by a tube / pipe 30. Meanwhile, second lower solenoid valve 27 is connected to main discharge outlet 6 by a tube / pipe 31 and to the volume compensator vessel 25 through a tube / pipe 32. Tubes / pipes 30 and 32 can converge to a T joint into which volume compensator vessel 25 is connected by tube / pipe 33. In applications where the condensation pressure is less than atmospheric, the opening of the upper solenoid valve 26 triggers a circulation of fluid due to pressure difference from the volume compensator vessel 25 to the accumulation section 19, increasing the level in the latter. Under the same operating conditions, in the opposite way, the opening of the lower solenoid valve 27 triggers a fraction of the fluid to flow from the pipe 34 or “discharge line”, owing to the pressure differential generated by pump 23, towards the volume compensator vessel 25, reducing the working fluid inventory in the closed circuit, resulting in a decrease in the liquid level in the accumulation section 19. If the liquid level in the accumulation section 19 is low enough, the floating element 20 is completely out of the liquid, surrounded by vapor. In this condition, due to its own weight and the weight of the stem 35 linked to it, the floating element 20 is in its lower position, sustained by a support structure 22. The plug of the flow control valve 21 rigidly linked to the floating element 20 through the stem, it is also in the lower position of its travel. Flow control valve 21 is designed in such a way that, when the plug moves to its lower position, it produces its maximum opening, allowing the fluid flow rate, that enters through the secondary upper feed inlet 12, to be the maximum possible for the entire installation. If the liquid level in the accumulation section 19 is high enough, the floating element 20 is completely flooded. In this condition, the buoyant force experienced by the floating element 20 is maximum and produces the maximum possible degree of closure in the flow control valve 21. The floating element 20 and the internals of the flow control valve 21 are sized in such a way that when the maximum possible degree of closure of the flow control valve 21 is reached, a minimum flow rate of fluid is preserved to facilitate the starting and stopping operations of the equipment. With the previously described mechanism, it is possible to regulate the flow rate of cold working fluid via flow control valve 21, actuated through floating element 20, whose position is established by the liquid level in the accumulation section 19 controlled through of the operation of solenoid valves 26 and 27. An associated electronic controller 45 uses the flow rate value that is recorded by the flow meter 13 and sends an electrical signal to open the upper solenoid valve 26 or the lower solenoid valve 27 according to the need to increase or decrease the flow rate. In this way, the flow control system is made up of a flow control valve 21 completely integrated within the hermetic and sealed module or container 2, with the resulting construction and maintenance advantages of not requiring seals or gaskets for its correct operation. Furthermore, this control system is completed with a pair of solenoid valves 26 and 27, or another type of simple “open / close” type valve, that function as indirect actuators of the flow control valve 21, with the consequent simplification in the manufacturing and maintenance requirements associated with conventional pneumatic and / or electrical actuators, and their complex integration within the hermetic and sealed module or container 2. Additionally, the flow control method described above allows for dispensing with a level control system in the accumulation section 19, commonly used to ensure the presence of an adequate liquid column for the proper operation of the circulation pump 23, preventing the passage of vapor into the latter, level control system that is typically implemented through a steam trap. In the device described in this disclosure it is possible to ensure an adequate liquid level in the accumulation section 19 through the flow measurement carried out by the flow meter 13. In accordance with the explanation above, if the system is operated at a flow rate lower than the maximum flow rate that can be achieved for a given installation, it can be ensured that the floating element 20 is partially flooded and consequently that the liquid level in the accumulation section 19 is such that it does not allow vapor to enter the circulation pump 23. Similarly, if the system is operated at a flow rate higher than the minimum flow rate of said specific installation, it is possible to ensure that the floating element 20 is partially flooded and consequently that the contact medium 11 is not flooded with condensate. In this way, this device has the additional advantage of not requiring a level measurement system or a steam trap, reducing costs and minimizing construction complexity, in addition to facilitating its operation. Aspects of the disclosure allow controlling the condensation temperature and, consequently, the pressure of the condenser, during the normal operation of the device, thanks to the flow control system, in a pressure range determined by the minimum and maximum flow range mentioned earlier. The variation in operating flow rate established by the flow control valve 21 allows the condenser to operate at a certain temperature and pressure, independently of the thermal load received from the hot source. On the other hand, since all the main components are confined in a single hermetic containment, the entry of non- condensable gases through gaskets, seals and / or connections is reduced, which improves the condensation efficiency. Likewise, certain embodiments of the disclosure only have one temperature sensor, one flow sensor and two solenoid valves (open / closed), which reduces the complexity associated with using two pumps that require frequency regulators and greater maintenance as described above. Further, the pump described herein can perform at least two functions: fluid circulation to overcome pressure losses throughout the refrigeration circuit of the thermal cycle, and driving the working fluid, defined by the flow regulator 36, to achieve the desired vapor conditions in the vapor generator 4. Flow regulator 36 can include, by way of example only, a control valve, a positive displacement pump, or any combination of pumps and valves as the ordinarily-skilled artisan may consider appropriate in connection with a particular application of the present teachings. The design of flow regulator 36 can be defined by the supply pressure requirement to the vapor generator, which may be higher or lower than the pressure supplied by the circulation pump 23. Another aspect of the disclosure is that the vacuum condition required in the condenser during operation is achieved by driving liquid from the condensation section 10 to the initially empty volume compensator vessel 25, through the same system of the aforementioned solenoid valves 26 and 27. The non-condensable gases that enter the installation in the loading operation of the circuit are eliminated during the start-up operation of the equipment, with the advantage that once the loading operation with the working fluid, start-up operation and non-condensable elimination operation have been carried out, the equipment can be turned OFF and ON without having to carry out the entire process again, thanks to its closed system configuration with the volume compensator vessel 25. Thanks to the system of solenoid valves 26 and 27 mentioned above, it is possible to carry out a start and stop operation in a simple way and allows the circuit to be completely flooded when the equipment is in a stopped or turned off state, thus ensuring that no point in the entire thermal circuit is in vacuum conditions, which would allow the entry of non-condensable gases. In this way, the disclosure provides a compact and hermetic device in which it is possible to ingeniously integrate several of the components that make up a Heller- type Rankine Cycle (e.g., vapor expander, electric generator, direct contact condenser, pump, and flow control), providing this equipment with innovative and advantageous features, not only in terms of cost, effectiveness and ease of installation and maintenance, but also in regard to operational simplicity. Thanks to the integration achieved, the design of a direct contact condenser and the fact that no extra lubricating agents are required in the bearings, the equipment operates with a single working fluid, where the tightness of the internal conduits is not critical. This integration, added to the good confinement within a single hermetic container, allows working in thermodynamic vacuum conditions without the need to expose the rest of the installation to such a condition, minimizing the possibility of non-condensable gases entering and prevents the loss of working fluid to the environment. When arranged in a suitable installation (Heller- type Rankine cycle), as shown to good advantage in Figure 2, it is possible from a high or low temperature thermal source, to obtain electrical energy thanks to the vapor expander 8 associated with the electric generator 9, and low temperature thermal energy (for example 60-120ºC) thanks to the working fluid flow in liquid phase that leaves the equipment through the main discharge outlet 6. This output flow with positive pressure is capable of delivering its thermal energy in a fluid-air heat exchanger 14, which can be, for example, an arrangement of radiators for heating (Figure 2) or an air cooler with ambient air (Figure 8), which represents the heat sink or cold source of the thermal cycle. With the device described herein in such a thermal cycle configuration, it is possible to work with different types of working fluids, such as: water, refrigerants (type HFCs or HFOs), hydrocarbons, siloxanes, among others depending on the hot source and the system requirements. By way of further explanation, certain aspects of the instant disclosure, which will be discussed with references to Figures 2 and 8, further differentiate the teachings herein from a conventional Rankine Cycle. It should be understood that the following aspects are exemplary only and are not limiting. For example, the fluid flow rate in liquid phase (condensate) that leaves the equipment at the bottom, only a part is sent to the vapor or steam generator, the rest is sent to the heat sink or cold source, refrigeration circuit of the cycle. The fluid circulation throughout the entire thermal cycle is achieved with a single pump integrated into the equipment. The thermal cycle is made up, then, of a single hydraulic circuit, so the components that make it up are reduced, such as pumps, expansion vessels, valves and additional instrumentation necessary in each independent hydraulic circuit. In this way, a vertical and aligned arrangement of the components in a single confinement structure is provided, being a cylindrical structure, completely hermetic, sealed with connection flanges between sections and free of mechanical seals and external movable parts. Thus, aspects of the disclosure present only four connections for input and output of working fluid, and a series of sealed, smaller connections for instrumentation and electrical conduction. It should be noted that the parts corresponding to the vapor expander, electric generator, condenser phase contact medium, floating element, spraying device, and circulation pump, may be supported by support structures, which can be mounted within said hermetic and sealed module. As mentioned, the vapor expander 8 and electric generator 9 are arranged in a hermetic confinement to avoid leaks or infiltrations in vacuum conditions, allowing the cooling of the electric generator 9 to be carried out with the working fluid in cold liquid phase that returns from the heat sink (radiators / air coolers) at the lowest temperature of the circuit. As a result of this, the fluid is preheated, with the heat extracted from the electric generator, before entering the condensation section 10. The cooling system may be include, without limitation, ducts confined only to the stator of the electric generator, so that the working fluid in the liquid phase does not come into contact with other parts of the equipment such as the integral rotary shaft or the bearings, avoiding possible leakage and viscous friction problems. Furthermore, being in liquid phase the heat transfer coefficients increase, improving the cooling efficiency. In a second embodiment of the disclosure, as illustrated in Figure 4, the condensation of the working fluid occurs at a pressure higher than atmospheric, due to its thermodynamic properties and the operating conditions of the system. This can happen, as an example, but not as a limitation, if the working fluid is an organic fluid of hydrofluorocarbons (HFCs) type similar to those used in conventional refrigeration equipment, even if condensation takes place at temperatures close to room temperature. Due to the action of the circulation pump 23, the pressure of line 34 is higher than the pressure of the condensate accumulation section 19 and, consequently, even higher than the atmospheric pressure. The transfer of liquid between the volume compensator vessel 25 and the hermetic and sealed container 2 is obtained via a flow control arrangement that comprises a bidirectional positive displacement pump 37, reversible in type, including, but not limited to, vanes, gears, lobes, etc. The pressure in the volume compensator vessel 25 can vary as its liquid content changes, actuating said positive displacement pump 37, the working fluid can flow in one direction or another, independently of the pressures on either side of it. The volume compensator vessel 25 for this embodiment of the disclosure can be formed by a pressurized container at a pressure higher than atmospheric pressure, lacking internal membranes. The pressure in this vessel varies with the increase or decrease in the volume of liquid contained therein. It should be noted that positive displacement pump 37 is connected to the volume compensator vessel 25 through pipe 33, while it is connected to secondary lower feed inlet 28 through a pipe 38. Likewise, positive displacement pump 37 is controlled via the electronic controller 45, which in turn is connected to flow meter 13. In a third embodiment of the disclosure, as illustrated in Figure 5, the circulation pump 23 is mounted externally to the hermetic and sealed module or container 2, connected to the bottom of the accumulation section 19 through a lower connection 39 that allows the suction of the condensed fluid by the pump 23. This configuration allows the use of pumps of any size or complexity, even with auxiliary systems for cooling the pump internals, whose assembly within the containment might be challenging. For cases in which the condensation pressure is less than atmospheric, as in the case of water, the pump suction pipe and part of its casing work under vacuum conditions. In order to prevent the entry of non-condensable gases, these pump components must be correctly sealed. In a fourth embodiment of the disclosure, as illustrated in Figure 6, a first pump 23 is mounted inside the hermetic and sealed module or container 2, in the accumulation section 19. This pump has sufficient pumping capacity to raise the pressure of the condensed fluid above atmospheric pressure and drive it out of the hermetic and sealed module or container 2 through a lower connection 40. A second circulation pump 41, or set of pumps, is linked to lower connection 40 and receives the outgoing working fluid flow at a pressure higher than atmospheric. At the same time, this second circulation pump 41 or set of pumps further increases the pressure of the fluid and drives it to the necessary circuit or circuits. This configuration allows the use of one or more pumps of any type and complexity, through removable connections, preventing the entry of non- condensable gases into the hermetic and sealed module or container 2 since it does not expose external connections to vacuum. In a fifth embodiment of the disclosure, as illustrated in Figures 7 and 8, a regenerator 42 is located in the condensation section 10 and receives the downward flow of expanded vapor in the expansion section 7, after the latter comes into contact with the cold liquid fluid on the phase contact medium 11. The regenerator 42 is formed by a heat exchanger in which one of the streams circulates confined to a series of closed conduits and the other stream flows externally on the exposed surface of the ducts. This exchanger can be, by way of example but not limited to, a tube or set of finned tubes. As seen in Figure 7, a fraction of the fluid driven by the pump 23 is diverted to the internal tubes of the regenerator 42 through a connection or series of connections 43 contained within the hermetic and sealed module or container 2, which may also be external to this, depending on the application. This fluid fraction circulates in countercurrent to the vapor coming from the expansion section 7, which flows through the finned tubes of the regenerator 42, where it delivers part of its heat to said liquid stream driven by the pump 23, before continuing towards the condensation process. An upper secondary outlet 44 at the top of the condensation section 10 allows the preheated working fluid to leave the hermetic and sealed module or container 2 to the flow control system 36 and subsequently to the vapor generator 4. According to Figure 8, in a Heller-type cycle, the arrangement of Figure 7 can be connected to volume compensator vessel 25 via a control device that can include a positive displacement pump 37 such as the one described above (although this configuration is not limiting insofar as the arrangement of solenoid valves 26 and 27 illustrated in Figure 2 may alternatively be used depending on the working fluid and operating conditions). Likewise, in figure 8 it can be seen that the connection or connection series 43 is developed outside the hermetic and sealed module 2, though this is also merely exemplary and not limiting. The configuration described in Figures 7 and 8 presents various advantages over extant thermal cycles with regenerator. For instance, the integration of the regenerator 42 and all its connections within the hermetic and sealed module 2 reduces the occurrence of fluid losses to the environment, which in turn reduces the criticality of the seals and thus the costs and maintenance requirements. As another example, the manufacture of the regenerator 42 is simplified compared to conventional designs, such as shell and tube or plate exchangers, given that the same container is used to contain the vapor stream. Although several embodiments have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention. For example, one of ordinary skill in the art will appreciate that any of the configurations for the flow control system presented in the embodiments of Figures 3 and 4 may be combined with the other embodiments presented in Figures 6, 7 and 8 depending on the system requirements. All directional references (e.g., upper, lower, upward, downward, left, right, leftward, rightward, top, bottom, above, below, vertical, horizontal, clockwise, and counterclockwise) are only used for identification purposes to aid the reader’s understanding of the present invention, and do not create limitations, particularly as to the position, orientation, or use of the invention. Joinder references (e.g., attached, coupled, connected, and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appendedclaims.

Claims

CLAIMS 1. An integrated hermetic device for Combined Heat and Power (CHP) energy generation arrangements, such as Heller-type thermal cycles, comprising: a hermetic and sealed module or container that has at least one main fluid feed inlet and at least one main fluid discharge outlet, said hermetic and sealed module or container including, internally in a vertical and descending manner: a) at least one expansion section of said fluid in a vaporized state entering through said main feed inlet; b) at least one condensation section of said fluid in an expanded vapor state exiting through said first expansion section, wherein said condensation section comprises: at least one secondary feed inlet for said fluid in a liquid state, at least one valve to control the fluid flow entering through said secondary feed inlet, at least one device for spraying the fluid passing through the flow control valve adjacent to said secondary fluid feed inlet, and at least one phase contact medium arranged below the spraying device; andc) at least one accumulation section of the condensed fluid through said condensation section, wherein said accumulation section comprises: a space for accumulation of a volume of condensed fluid, at least one floating element operatively connected to said control valve through a stem, at least one circulation pump being in communication with said main fluid discharge outlet.

2. The integrated hermetic device according to claim 1, wherein said at least one fluid expansion section comprises: at least one vapor expander disposed downstream of, and in communication with said main feed inlet, and at least one electric generator arranged downstream of, and connected to said vapor expander.

3. The integrated hermetic device according to claim 1, wherein said spraying device comprises a plurality of sprays of cold fluid coming from said secondary feed inlet.

4. The integrated hermetic device according to claim 1, wherein said flow control valve is a linear displacement valve.

5. The integrated hermetic device according to claim 1, wherein said accumulation section has, in a lower portion, at least one secondary feed connection which is linked to a flow control arrangement.

6. The integrated hermetic device according to claim 5, wherein said flow control arrangement comprises a volume compensator vessel, an upper solenoid valve and a lower solenoid valve, the upper solenoid valve and the lower solenoid valve operatively intercommunicating said volume compensator vessel with said accumulation section, and with the discharge of said circulation pump.

7. The integrated hermetic device according to claim 5, wherein said flow control arrangement comprises a bidirectional positive displacement pump that operatively communicates with said accumulation section.

8. The integrated hermetic device according to claim 5, further comprising a flow sensor element and an electronic controller for driving said flow control arrangement.

9. The integrated hermetic device according to claim 1, wherein said circulation pump is arranged within saidhermetic and sealed module or container, downstream of said floating element and upstream of said main discharge outlet.

10. The integrated hermetic device according to claim 1, wherein said circulation pump is arranged outside said hermetic and sealed module or container, and in connection with said main discharge outlet.

11. The integrated hermetic device according to claim 1, further comprising a second pump arranged outside said hermetic and sealed module or container and in operative connection with said circulation pump.

12. The integrated hermetic device according to claim 1, wherein said condensation section further comprises a heat exchanger arranged downstream of said expansion section and upstream of said spraying device, defining a flow of expanded fluid through the hot side thereof, said heat exchanger also being operatively connected at the cold side inlet with said main discharge outlet and contacted at the cold side outlet to a secondary discharge outlet of said containment.

13. The integrated hermetic device according to claim 1, wherein the fluid is water.

14. The integrated hermetic device according to claim 1, wherein the fluid is selected from organic fluids, refrigerant fluids, type HFCs, type HFOs, hydrocarbons, siloxanes.

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