JP2006046673A - Heat storage tank - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat storage tank improving heat storage density, and preventing leakage of a cold storage agent. <P>SOLUTION: The heat storage tank is provided with the cold storage agent 19 containing water to be vaporized and condensed, a heat exchanger 21 immersed in the cold storage agent 19 and carrying out heat exchange between heat of vaporization and heat of the outside, a heat exchanger 22 arranged in a space (a condensation part 24) not holding the cold storage agent 19 in an interior of the heat storage tank 18, condensing water vapor from the outside to circulate it to the cold storage agent 19, and carrying out heat exchange between heat of condensation and heat of the outside, and one or a plurality of water vapor permeation pipes 18' immersed in the cold storage agent 19. In the heat storage tank 18, an exterior of the water vapor permeation pipe 18' faces the cold storage agent 19 and an interior of the pipe is communicated with the exterior, and it is used as a water vapor permeating means 20 for allowing permeation and vaporization of only water from the cold storage agent 19 of the exterior of the pipe to the interior of the pipe. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat storage tank, and is discharged from, for example, distributed power sources (fuel cells, micro gas turbines, gas engines, etc.), factories (incinerators, etc.), hot springs, homes (hot wastewater such as baths, exhaust gas), etc. It is a heat storage tank that can be used for a latent heat storage system and a latent heat storage method that function as a cold heat source and a heat source by effectively using waste heat at a relatively low temperature of about 100 ° C. to 100 ° C. In addition, for example, the present invention can be used in a latent heat storage system and a latent heat storage method that can apply a compression heat pump that uses nighttime power.

  International arrangements for global warming gas emissions regulations at the 3rd Conference of the Parties to the United Nations Framework Convention on Climate Change (COP3) held in Kyoto in 1997, the implementation of the revised Energy Conservation Law in 1999, and rising crude oil prices, etc. Therefore, there is a very strong social demand for resource and energy conservation in Japan.

  In terms of policy, various deregulation measures for energy supply such as electricity and gas, promotion of the use of renewable energy with low environmental impact and unused energy such as exhaust heat, and assistance for higher efficiency of conventional energy use The construction and proposal of new energy systems are being promoted, such as the development of systems.

  In particular, in the development of small distributed cogeneration systems using micro gas turbines and fuel cells, which are the core of the next generation energy system revolution, effective use of low-level thermal energy emitted from these systems Method development is an important issue.

  Examples of conventional low-temperature waste heat recovery technology include an adsorption / desorption heat pump system using silica gel, zeolite, and activated carbon. This system uses an adsorption / desorption reaction using a substance with water vapor adsorption / desorption ability such as silica gel, and the detailed system configuration is large. It stores an adsorption / desorption tank that performs an adsorption / desorption process, and desorbed water (latent heat medium). It consists of two zones with a heat storage tank.

  The two zones are connected in a reduced pressure (vacuum) state by a gas pipe, and heat storage and heat collection are performed by moving water vapor (latent heat medium) in the pipe. The adsorption / desorption tank is provided with a heating device (heat exchanger or heater) for desorbing the adsorption medium from silica gel or the like, and a heat exchanger for recovering the adsorption heat generated in the adsorption process. In addition, the heat storage tank is provided with a condenser for condensing moisture moved from the adsorption / desorption tank in the desorption process, and a heat collecting heat exchanger for collecting cold heat generated when the medium evaporates in the adsorption process. Yes.

JP 9-313903 A JP-A-9-131516 JP 59-179112 A JP 59-147605 A JP 59-109203 A

<Problems of latent heat storage system>
In the consumer and industrial sectors, the shift to cogeneration and distributed power generation (cogeneration) is progressing with the aim of saving energy. However, even in such a situation, a problem for energy saving is that low-energy waste heat of 100 ° C. or less is not effectively used.

  In anticipation of the future, small distributed power sources such as polymer electrolyte fuel cells (PEFC), micro gas turbines, and micro gas engines, which are expected to have significant energy saving effects from the perspective of overall thermoelectric thermal efficiency, are used in the consumer sector (household (1-5 kW)) It is thought that it will spread dramatically in business use (10 to several tens of kW).

  In such a distributed power source, waste heat is built on the premise that it will be used in the form of hot water or steam, but when the power load is high, heat is surplus from the balance of thermoelectric demand and remains unused. There is concern that it will actually reduce the overall efficiency and not contribute to energy saving.

  Thus, the strong need for the effective use of low energy waste heat still appears in the civilian or industrial sectors. However, the current technical problem is that a heat system that efficiently recovers low-energy waste heat cannot be constructed.

  The reason behind the delay in the introduction and spread of latent heat storage systems is a compact, inexpensive, high-density, high-performance, easy-to-use adsorption / desorption tank and heat storage tank, even though the latent heat storage system is an active energy-saving technology. This is due to the fact that creative research and development for the development of a latent heat storage system integrating these was not conducted.

<Subjects for latent heat storage systems, especially adsorption / desorption tanks>
That is, in the conventional adsorption / desorption heat pump system described above, the temperature level of available waste heat is about 150 ° C., and there is a problem that the efficiency of the system is significantly reduced at a temperature level lower than this. This is derived from the performance of the adsorption / desorption material (silica gel, zeolite, activated carbon, etc.). Moreover, since the mass-specific adsorption capacity of the adsorption / desorption substance is low, the system is enlarged.

  Also, in the adsorption process, when the water vapor moving from the heat storage tank is adsorbed to the adsorption / desorption material filled in the tank, it is difficult for the water vapor to diffuse uniformly into the adsorption / desorption material. There is a problem that it cannot be used.

<Subjects for latent heat storage systems, especially heat storage tanks>
Moreover, since the cold storage density of the water which is a latent heat medium stored in the heat storage tank is low, it is necessary to prepare a large amount of water, leading to enlargement of the heat storage tank. Furthermore, when components other than moisture contained in the latent heat medium leak from the heat storage tank and enter the sorption / desorption tank, the performance of the sorption / desorption agent may be reduced.

  The present invention has been made in view of the above situation, and provides a heat storage tank that improves the heat storage density to make the heat storage tank compact, and prevents components other than moisture contained in the latent heat medium from leaking to the outside. The purpose is to do.

<Heat storage tank>
The heat storage tank according to the present invention for solving the above problems is
A heat storage tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A regenerator that contains water, evaporates and condenses the water, a water vapor permeation means that permeates and evaporates only water from the regenerator, and first heat that exchanges heat during the evaporation with external heat. A heat storage tank characterized by comprising heat exchange means and second heat exchange means for condensing the water vapor from the outside and circulating it to the cold storage agent and exchanging heat at the time of condensation with external heat. is there.

  By applying water vapor permeation means in the heat storage tank, only moisture is transferred from the heat storage tank to the outside, and components other than moisture contained in the cool storage agent are prevented from leaking from the heat storage tank, and water is evaporated. It makes it possible to effectively transfer latent heat to the cold storage agent.

The heat storage tank according to the present invention for solving the above problems is
A heat storage tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A regenerator stored in the heat storage tank, containing water, and evaporating and condensing the water;
First heat exchange means immersed in the cold storage agent and exchanging heat during the evaporation with external heat;
The heat storage tank is disposed in a space where the cold storage agent is not stored, and condenses the water vapor from the outside and circulates it to the cold storage agent, and exchanges heat at the time of the condensation with external heat. Heat exchange means;
Having one or more water vapor transmission tubes immersed in the cold storage agent,
The water vapor transmission pipe is a water vapor transmission means for allowing the outside of the pipe to face the cold storage agent and the inside of the pipe to communicate with the outside, and allowing only water from the cold storage agent outside the pipe to pass through and evaporate into the pipe. It is a heat storage tank characterized by being.

In the above heat storage tank,
The cold storage agent is a heat storage tank containing an emulsion.

  By further mixing an emulsion (for example, microcapsules) into the cold storage agent, the heat storage density of the cold storage agent is improved by utilizing the solid-liquid phase change of the emulsion. As the emulsion, it is preferable to use a low temperature coagulation type emulsion.

<Latent heat storage system, latent heat storage method and sorption / desorption tank>
In addition, it is effective if the said heat storage tank is applied to the following latent heat storage system and the latent heat storage method, or used together with the following sorption / desorption tank.

A latent heat storage system having a sorption / desorption tank and a heat storage tank,
The sorption / desorption tank is a sorption / desorption agent for sorption and desorption of water, heat exchange means for exchanging heat at the time of sorption or desorption with external heat, and water vapor from the heat storage tank is condensed. Water vapor permeation means that is permeated and evaporated later to supply the sorbent / desorbent substantially uniformly,
The heat storage tank contains water, a cold storage agent that evaporates and condenses the water, heat exchange means that exchanges heat during the evaporation with external heat, and condensates water vapor from the sorption / desorption agent. A latent heat storage system comprising heat exchange means for circulating to the cold storage agent and exchanging heat at the time of condensation with external heat.

  Compared to conventional silica gels and zeolites, it is possible to operate at low temperatures, and by adopting an organic sorbent / desorbent with a large amount of heat storage, the sorption / desorption temperature is extremely low, ranging from about 30 ° C to 100 ° C. Enables operation in the region and improves mass ratio or volume ratio sorption / desorption capability.

  In addition, the water vapor from the heat storage tank is not directly supplied to the adsorption / desorption agent in the sorption / desorption tank, but is supplied through a water vapor transmission means that once condenses moisture (latent heat medium) and transmits / evaporates only water. Accordingly, it is possible to diffuse moisture substantially uniformly into the sorbent / desorbent. This also greatly reduces the resistance to material movement in the sorption / desorption tank.

In the latent heat storage system,
The latent heat storage system, wherein the heat storage tank has water vapor transmission means for transmitting and evaporating only water from the cold storage agent.

In the latent heat storage system,
There is a space between the sorption / desorption agent and the water vapor transmission means,
The water vapor that has permeated and evaporated through the water vapor transmission means is supplied to the sorbent / desorbent through the space substantially uniformly, and water desorbed from the sorbent / desorbent moves from the space to the heat storage tank. A latent heat storage system characterized by that.

In the latent heat storage system,
The said cool storage agent contains emulsion, The latent heat storage system characterized by the above-mentioned.

<Latent heat storage method>
A latent heat storage method for performing a sorption process and a desorption process using a sorption / desorption tank and a heat storage tank,
The sorption step evaporates water from the cold storage agent containing water in the heat storage tank, exchanges the heat at the time of evaporation with external heat, and converts the water vapor from the heat storage tank by water vapor transmission means. A latent heat storage method characterized by substantially uniformly sorbing to the sorbent / desorbent in the sorption / desorption tank by allowing it to permeate and evaporate after being condensed, and to exchange heat during the sorption with external heat. .

In the latent heat storage method,
In the desorption step, water is desorbed from the sorption / desorption agent in the sorption / desorption tank, the heat during the desorption is exchanged with external heat, and water vapor from the sorption / desorption tank is condensed, A latent heat storage method characterized by circulating to a cool storage agent in a heat storage tank and exchanging heat at the time of condensation with external heat.

In the latent heat storage method,
A latent heat storage method wherein only water is permeated and evaporated by a water vapor transmission means when water is evaporated from the cold storage agent in the sorption step.

In the latent heat storage method,
There is a space between the sorption / desorption agent and the water vapor transmission means,
The water vapor that has permeated and evaporated through the water vapor transmission means is supplied to the sorbent / desorbent through the space substantially uniformly, and water desorbed from the sorbent / desorbent moves from the space to the heat storage tank. A latent heat storage method characterized by that.

In the latent heat storage method,
The said cool storage agent contains an emulsion, The latent heat storage method characterized by the above-mentioned.

<Desorption / desorption tank>
A sorption / desorption tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A sorption / desorption agent for sorption and desorption of water, the heat exchange means for exchanging heat at the time of sorption or desorption with external heat, and permeating and evaporating after condensing water vapor from the outside A sorption / desorption tank comprising water vapor transmission means for supplying the sorbent / desorbent substantially uniformly.

In the above sorption / desorption tank,
There is a space between the sorption / desorption agent and the water vapor transmission means,
The water vapor that has permeated and evaporated through the water vapor transmission means is supplied to the sorbent / desorbent substantially uniformly through the space, and the water desorbed from the sorbent / desorbent moves from the space to the outside. A sorption / desorption tank.

A sorption / desorption tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A water vapor introduction part for introducing water vapor from the outside, and one or a plurality of sorption / desorption tubes provided in the water vapor introduction part,
The sorption / desorption tube has a double-pipe structure composed of an inner tube and an outer tube,
The inner pipe is constituted by an outer part constituted by a sorption / desorption agent for sorption and desorption of water, and an inner part constituted by the heat exchange means for exchanging heat at the time of the sorption or desorption with external heat. And consist of
The outer tube is a water vapor permeable / desorption tank characterized in that the water vapor introduced into the water vapor introducing part is condensed and permeated / vaporized, and is supplied to the sorbent / desorbent substantially uniformly.

A sorption / desorption tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A portion through which heat from the outside flows, and one or a plurality of sorption / desorption tubes provided in the portion through which the heat flows,
The sorption / desorption tube has a double-pipe structure composed of an inner tube and an outer tube,
The outer tube includes an inner part constituted by a sorption / desorption agent that sorbs and desorbs water, and an outer part constituted by the heat exchange means that exchanges heat at the time of sorption or desorption with external heat. And consist of
The inner pipe is a water vapor introduction part that introduces water vapor from the outside into the pipe, condenses the water vapor introduced into the water vapor introduction part, permeates and evaporates it, and supplies it to the sorbent / desorbent substantially uniformly. A sorption / desorption tank characterized by being a water vapor transmission means.

In the above sorption / desorption tank,
There is a space between the sorption / desorption agent and the water vapor transmission means,
The water vapor that has permeated and evaporated through the water vapor transmission means is supplied to the sorbent / desorbent substantially uniformly through the space, and the water desorbed from the sorbent / desorbent moves from the space to the outside. A sorption / desorption tank.

<Adsorption / desorption tank>
In addition, it is effective if it uses together with the said thermal storage tank and the following adsorption / desorption tank.

An adsorption / desorption tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
An adsorption / desorption agent that adsorbs and desorbs water, the heat exchange means for exchanging heat at the time of adsorption or desorption with external heat, and water vapor from the outside is condensed and then permeated and evaporated to absorb the adsorption. An adsorption / desorption tank comprising a water vapor transmission means for supplying the desorption agent substantially uniformly.

  Even if conventional adsorption / desorption agents such as silica gel and zeolite are used, it is difficult to effectively use the filled adsorption / desorption material because it is difficult for water vapor to diffuse uniformly into the adsorption / desorption material by applying the water vapor transmission means. The problem can be solved.

In the adsorption / desorption tank,
Having a space between the adsorption / desorption agent and the water vapor transmission means;
The water vapor that has permeated and evaporated through the water vapor transmission means is supplied to the adsorbent / desorbent substantially uniformly through the space, and the water desorbed from the adsorbent / desorbent moves from the space to the outside. An adsorption / desorption tank characterized by

An adsorption / desorption tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A water vapor introduction part for introducing water vapor from the outside, and one or a plurality of adsorption / desorption tubes provided in the water vapor introduction part,
The adsorption / desorption tube has a double-pipe structure composed of an inner tube and an outer tube,
The inner tube includes an outer part constituted by an adsorption / desorption agent that adsorbs and desorbs water, and an inner part constituted by the heat exchange means for exchanging heat at the time of adsorption or desorption with external heat. Become
The adsorption / desorption tank, wherein the outer pipe is a water vapor permeation means for condensing and vaporizing the water vapor introduced into the water vapor introduction part and supplying the vapor to the adsorption / desorption agent substantially uniformly.

An adsorption / desorption tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A portion through which heat from the outside flows, and one or a plurality of adsorption / desorption tubes provided in the portion through which the heat flows,
The adsorption / desorption tube has a double-pipe structure composed of an inner tube and an outer tube,
The outer pipe is composed of an inner part constituted by an adsorption / desorption agent that adsorbs and desorbs water and an outer part constituted by the heat exchange means for exchanging heat at the time of adsorption or desorption with external heat. Become
The inner pipe is a water vapor introduction part that introduces water vapor from the outside inside the pipe, condenses the water vapor introduced into the water vapor introduction part, permeates and evaporates it, and supplies it to the adsorption / desorption agent substantially uniformly. An adsorption / desorption tank characterized by being a water vapor transmission means.

In the adsorption / desorption tank,
Having a space between the adsorption / desorption agent and the water vapor transmission means;
The water vapor that has permeated and evaporated through the water vapor transmission means is supplied to the adsorbent / desorbent substantially uniformly through the space, and the water desorbed from the adsorbent / desorbent moves from the space to the outside. An adsorption / desorption tank characterized by

According to the heat storage tank according to the present invention,
(1) The heat storage density can be improved by mixing an emulsion (for example, microcapsule) into the cool storage agent of the heat storage tank. As a result, the heat storage tank can be scaled down.

(2) By disposing the water vapor transmission means in the heat storage tank, only moisture can be transferred from the heat storage tank to the sorption / desorption tank as a latent heat medium, and components other than water contained in the cool storage agent leak from the heat storage tank. In addition to preventing this, the latent heat of vaporization of water can be effectively transferred to the cold storage agent. As a result, the heat storage tank can be scaled down.

(3) In addition, by installing a water vapor permeation means that allows only moisture (latent heat medium) to pass through in the sorption / desorption tank or in the adsorption / desorption tank used in combination with the cold storage tank according to the present invention, the sorption / desorption agent or adsorption / desorption agent is obtained. Water diffusion can be performed substantially uniformly. As a result, the volume utilization efficiency of the sorption / desorption agent or the adsorption / desorption agent can be improved.

(4) In the sorption / desorption tank used in combination with the regenerator according to the present invention, the sorption / desorption temperature is about 30 ° C. to 100 ° C. by applying “sorption / desorption agent” instead of “adsorption / desorption agent”. The operation in the extremely low temperature range is possible. As a result, it is possible to effectively use low-level waste heat such as a distributed power source (fuel cell, etc.), factory waste heat (incinerator, etc.), household waste heat (hot waste water, etc.), and hot springs.

  The low temperature region matches the waste heat temperature level of solid polymer fuel cells and the like that are expected to spread in the future, and is used as a heat source for driving a heat pump or as a heat storage source. -Heat can be used as a heat storage tank for heating, drying, or nighttime.

  Further, for business use and industrial use, low-temperature steam of about 100 ° C., low-temperature drain, or low-temperature exhaust gas, which has heretofore had little utility value, can be widely used as a heat process heat source.

<Latent heat storage system / Latent heat storage method>
Hereinafter, although an embodiment of the present invention is described in detail using a drawing, the present invention is not limited to this. FIG. 1 is a schematic configuration diagram of a latent heat storage system according to an embodiment of the present invention.

  As shown in FIG. 1, the latent heat storage system 10 according to the present embodiment includes a sorption / desorption tank 11, a heat storage tank 18, a steam pipe 26 connecting both tanks 11, 18, and a selection for controlling a steam flow path. It consists of valves 27a and 27b.

  The sorption / desorption tank 11 is filled inside, and a sorption / desorption agent 12 that sorbs and desorbs water vapor, and a heat exchanger 14 that exchanges heat between the heat of the sorption / desorption agent 12 and heat from outside the system 10, The water supply section 15 is a space for supplying water vapor from the heat storage tank 18 to the inside of the sorption / desorption tank 11, and is a space that is in contact with the sorption / desorption agent 12 and supplies water vapor generated from the sorption / desorption agent 12 to the heat storage tank 18. It comprises an evaporation section 16 and a water vapor transmission means 13 provided between the water vapor introduction section 15 and the evaporation section 16.

  The water vapor transmission means 13 includes a water vapor transmission film part 13b on the water vapor introduction part 15 side and a base material part 13a on the evaporation part 16 side, and the water vapor transmission film part 13b is a thin film made of silica having a thickness of about 5 to 10 μm. The base material portion 13a is a ceramic base material having a thickness of about 1 mm.

  The sorptive / desorbent is a polymer fine particle provided with a moisture absorption and desorption function on the polymer skeleton, and has a moisture absorption / release rate two to three times that of a conventional “adsorption / desorption agent” typified by silica gel. In addition, the conventional adsorption / desorption agent is crushed and pulverized with respect to repeated moisture absorption and desorption operations, whereas the sorption / desorption agent is not crushed and has excellent repetition characteristics.

  Under the control of the selection valve 27a, the steam pipe 26 is connected to the steam introduction section 15 or the evaporation section 16, and, as will be described in detail below, the steam pipe 26 is circulated from the heat storage tank 18 in the sorption process. The water vapor thus circulates in the water vapor introduction part 15, and in the desorption process, the water vapor desorbed and evaporated from the sorbent / desorption agent 12 to the evaporation part 16 flows through the water vapor pipe 26 toward the heat storage tank 18.

  The heat storage tank 18 is stored in the heat storage tank 18, and performs heat exchange between the cold storage agent 19 made of water, a freezing point depressant (antifreeze), and an emulsion, and heat exchange between the heat of the cold storage agent 19 and the heat from the outside of the system 10. A regenerator 21, a water vapor transmission means 20 that evaporates and permeates only moisture in the regenerator 19, an evaporation unit 23 that is a space for supplying permeated water vapor to the sorption / desorption tank 11, and a regenerator 19 in the heat storage tank 18. The heat exchanger 22 is installed in a non-reserved space and performs heat exchange between the latent heat of the water vapor from the sorption / desorption tank 11 and the heat from the outside of the system 10, and condenses the water vapor and circulates it to the cool storage agent 19. And the condensing part 24 which is the space to be condensed.

  The water vapor transmission means 20 includes a water vapor transmission film part 20b on the cold storage agent 19 side and a base material part 20a on the evaporation part 23 side, and the water vapor transmission film part 20b is a thin film made of silica having a thickness of about 5 to 10 μm. Yes, the base material portion 20a is a ceramic base material having a thickness of about 1 mm.

  The freezing point depressant (antifreeze) constituting the regenerator 19 is for preventing freezing of the regenerator 19 in the sorption process (evaporation of water from the regenerator 19) described in detail below. This is to improve the heat storage density of the cold storage agent 19 by utilizing the solid-liquid phase change.

  Under the control of the selection valve 27b, the water vapor pipe 26 is connected to the evaporation unit 23 or the condensation unit 24. As described in detail below, the vapor pipe 26 has evaporated from the cold storage agent 19 to the evaporation unit 23 in the sorption process. The water vapor flows through the water vapor pipe 26 toward the sorption / desorption tank 11, and the water vapor flowing through the water vapor pipe 26 from the sorption / desorption tank 11 flows through the condensing unit 24 in the desorption process.

<Sorption process in this system and method>
FIG. 2 is a diagram illustrating a sorption process in the latent heat storage system according to the embodiment of the present invention. In the sorption process, the selection valve 27a is opened to the water vapor introduction unit 15 side, and the selection valve 27b is opened to the evaporation unit 23 side.

  By making the inside of the system consisting of the evaporation section 23, the steam pipe 26, the steam introduction section 15 and the evaporation section 16 into a negative pressure state (about 30 torr) by the vacuum pump 30, the water content in the regenerator 19 through the steam transmission means 20. Only vapor is allowed to evaporate and permeate through the evaporating section 23 (selective evaporation 1 only with moisture).

  The generated water vapor is controlled by the selection valve 27b to flow through the water vapor pipe 26 toward the sorption / desorption tank 11 (water vapor 2 flowing through the pipe), and is controlled by the selection valve 27a to flow into the water vapor introduction section 15.

  The water vapor flowing into the water vapor introducing section 15 is uniformly condensed on the surface of the water vapor permeable film section 13b in the water vapor permeable means 13 (uniform condensation 3) and then evaporated again when passing through the water vapor permeable means 13 to form water vapor ( Evaporation 4) and flows into the evaporation section 16. As a result, it is possible to supply water vapor without any spots on the surface of the sorbent / desorbent 12 in the evaporation section 16.

  When water vapor is directly introduced from the water vapor pipe 26 to the evaporation unit 16 without passing through the water vapor transmission means 13, a large amount of water vapor is supplied to the sorbent / desorption agent in the vicinity of the introduction port to the evaporation unit. Further, there is a risk that it is difficult to supply water vapor to the sorbent / desorbent.

  On the other hand, by introducing into the evaporation part 16 through the water vapor transmission means 13 as in the present embodiment, it becomes possible to diffuse and supply water vapor without any spots through the uniform condensation 3 and the re-evaporation 4. ing. Moreover, it is possible by this effect | action to reduce the water | moisture-content spreading | diffusion resistance of the filled sorbent / desorbent 12. FIG.

  Note that the balance of heat generated during the condensation 3 and the re-evaporation 4 of the water vapor in the water vapor transmission means 13 is completed in the water vapor transmission means 13.

  Finally, the water vapor uniformly supplied to the sorbent / desorbent 12 is uniformly sorbed on the sorbent / desorbent 12 (uniform sorption 5).

In the sorption process described above, when the moisture in the regenerator 19 evaporates and permeates through the water vapor permeation means 20 to the evaporation unit 23 (selective evaporation 1 of only water), the latent heat of vaporization of water is immersed in the regenerator 19. It collect | recovers with the made heat exchanger 21, and uses as a cold-heat source. That is, the medium V ₁ from the outside is cooled by latent heat of vaporization and used as the medium V ₂ after passing through a relatively low-temperature heat exchanger.

Further, when water vapor uniformly supplied to the sorbent / desorbent 12 sorbs on the sorbent / desorbent 12 (uniform sorption 5), the sorption heat generated from the sorbent / desorbent 12 contacts the sorbent / desorbent 12. It collect | recovers with the made heat exchanger 14, and uses as a heat source. That is, the medium V ₃ from the outside is heated by sorption heat and used as the medium V ₄ after passing through a relatively high temperature heat exchanger.

<Desorption process in the present system and method>
FIG. 3 is a diagram illustrating a desorption process in the latent heat storage system according to the embodiment of the present invention. In the desorption process, the selection valve 27a is opened on the evaporation unit 16 side, and the selection valve 27b is opened on the condensation unit 24 side.

  The inside of the system consisting of the evaporation section 16, the steam pipe 26 and the condensation section 24 is brought into a negative pressure state (about 30 torr) by the vacuum pump 30, and the sorbent / desorbent 12 is removed by the heat exchanger 14 brought into contact with the sorbent / desorbent 12. By heating, moisture adsorbed on the sorbent / desorbent 12 is desorbed / evaporated (desorption / evaporation 6).

  The water vapor generated by desorption / evaporation is controlled by the selection valve 27a to flow through the water vapor pipe 26 toward the heat storage tank 18 (water vapor 7 flowing through the pipe), and is controlled by the selection valve 27b to flow into the condensing unit 24. .

  Finally, the water vapor flowing into the condensing unit 24 is cooled and condensed (cooled / condensed 8) by the heat exchanger 22 installed in the space where the regenerator 19 inside the heat storage tank 18 is not stored, and becomes moisture. It is collected in the cold storage agent 19.

In the above desorption process, moisture desorption / evaporation latent heat is supplied by the heat exchanger 14 in contact with the sorption / desorption agent 12, and the sorption / desorption agent 12 is heated by the heat exchanger 14 to be collected in the sorption / desorption agent 12. Desorbed / evaporated (desorbed / evaporated 6) the water that is being worn. That is, the medium V ₅ from the outside passing through the heat exchanger 14 is cooled by the desorption / evaporation latent heat, and discharged as a medium V ₆ after passing through the heat exchanger having a relatively low temperature. Thereby, unused thermal energy can be recovered.

Further, when the water vapor flowing into the condensing unit 24 is cooled / condensed (cooling / condensation 8) by the heat exchanger 22, the heat of condensation is recovered by the heat exchanger 22 and used as a heat source. That is, the medium V ₇ from the outside is heated by the condensation heat and used as the medium V ₈ after passing through a relatively high-temperature heat exchanger.

  In the basic cycle consisting of the above sorption process and desorption process, a combination of the sorption / desorption agent 12 with excellent sorption / desorption characteristics and the water vapor transmission means 13 and 20 that transmits only moisture from the cold storage agent 19 makes it highly efficient and compact. The latent heat storage system 10 can be obtained.

  Further, by providing the water vapor transmission means 20, it is possible to prevent the freezing point depressant (antifreeze) and emulsion from entering the water vapor pipe 26, and by providing the water vapor transmission means 13, it is included in the cold storage agent 19. It is possible to prevent the freezing point depressant (antifreeze) and emulsion from being mixed into the sorption / desorption agent 12.

<Example of specific structure of sorption / desorption tank>
FIG. 4 is a partial schematic external view (a) of a sorption / desorption tank of the latent heat storage system according to the embodiment of the present invention, a diagram (b) for explaining a sorption process in an A-direction arrow section, and an A-direction arrow view. It is a figure (c) explaining the desorption process in a cross section.

  In the sorption / desorption tank 11 according to this embodiment, as shown in FIG. 4, a plurality of sorption / desorption tubes 11 ′ (one sorption / desorption tube is shown in FIG. 4) are arranged in the space of the water vapor introduction section 15. It becomes. The sorption / desorption tube 11 ′ has a double tube structure including an outer tube and an inner tube, the outer tube is a water vapor introduction portion 15, and the inner tube is a medium flow path of the heat exchanger 14. A space for the evaporation portion 16 is formed between the outer tube and the inner tube.

  The outer tube is a water vapor transmission means 13 including a base material portion 13a constituting an inner portion of the outer tube and a water vapor permeable film portion 13b constituting the outer portion of the outer tube. The inner tube is an inner portion of the inner tube. The heat exchanger 14 that constitutes and the sorbent / desorbent 12 that constitutes the outer part of the inner tube.

  The sorption process in the sorption / desorption tank 11 according to the present embodiment is as described with reference to FIG. 2, and will be further described with reference to the cross-sectional structure diagram of the sorption / desorption tube shown in FIG.

  After the water vapor introduced into the water vapor introducing part 15 which is a space for accommodating the sorption / desorption pipe 11 ′ is uniformly condensed (uniform condensation 3) on the surface of the water vapor permeable film part 13b in the water vapor permeable means 13 which is the outer pipe, When passing through the water vapor transmission means 13, it evaporates again to become water vapor (evaporation 4) and flows uniformly into the evaporation section 16.

The water vapor that has flowed into the evaporation section 16 is uniformly supplied to the sorbent / desorbent 12 constituting the outer portion of the inner tube, and is uniformly sorbed onto the sorbent / desorbent 12 (uniform sorption 5). At this time, the sorption heat generated from the sorbent / desorbent 12 is contacted with the sorbent / desorbent 12 and recovered by the heat exchanger 14 constituting the inner portion of the inner tube and used as a heat source. That is, the medium V ₃ from the outside is heated by sorption heat by passing through the medium flow path of the heat exchanger 14, and is used as the medium V ₄ after passing through the relatively high temperature heat exchanger. .

  The desorption process in the sorption / desorption tank 11 according to the present embodiment is as described with reference to FIG. 3, and will be further described with reference to the cross-sectional structure diagram of the sorption / desorption tube shown in FIG.

The inside of the system such as the evaporation section 16 is brought into a negative pressure state (about 30 torr), and the sorbent / desorbent 12 constituting the outside of the inner pipe is heated by the heat exchanger 14 constituting the inside of the inner pipe, thereby sorption / desorption. The water sorbed on the agent 12 is desorbed and evaporated (desorption / evaporation 6). Thereby, the effective utilization (recovery) of the waste heat utilized as a heat source can be performed. That is, the medium V ₅ from the outside passes through the medium flow path of the heat exchanger 14, is cooled by the desorption / evaporation latent heat, and is used as the medium V ₆ after passing through the relatively low-temperature heat exchanger. The

<Example of specific structure of heat storage tank>
FIG. 5: is a partial schematic external view (a) of the heat storage tank of the latent heat storage system which concerns on embodiment of this invention, and the figure (b) explaining the sorption process in a B direction arrow cross section.

  As shown in FIG. 5, the heat storage tank 18 according to the present embodiment includes a plurality of water vapor transmission pipes 18 ′ as water vapor transmission means in the cold storage agent 19 (FIG. 5 shows one water vapor transmission pipe). Furthermore, the heat exchanger 21 is arrange | positioned and the heat exchanger 22 (not shown) is arrange | positioned in the space where the cool storage agent 19 in the heat storage tank 18 is not stored.

  The water vapor transmission pipe 18 ′ has a single pipe structure, the cold storage agent 19 on the outside of the pipe, and the evaporation part 23 on the inside of the pipe. The base material portion 20a constituting the inner portion of the pipe, and the outer portion of the pipe And a water vapor permeable membrane portion 20b.

  The sorption process in the heat storage tank 18 according to the present embodiment is as described with reference to FIG. 2, and will be further described with reference to the cross-sectional structure diagram of the water vapor transmission pipe shown in FIG.

  By setting the inside of the system such as the evaporation unit 23 to a negative pressure state (about 30 torr), only the water in the cool storage agent 19 is evaporated and permeated to the evaporation unit 23 via the water vapor transmission pipe 18 ′ (selective evaporation 1 only of water). ). At this time, the latent heat of vaporization of water is collected by a heat exchanger 21 immersed in the cold storage agent 19 and used as a cold heat source.

That is, the cool storage agent 19 is cooled by the evaporation of water, and the cooling heat is transmitted to the heat exchanger 21 (generation and movement 9 of cold heat due to water evaporation), and the medium V ₁ from the outside is the medium of the heat exchanger 21. By passing through the flow path, it is cooled by latent heat of vaporization and used as a medium V ₂ after passing through a relatively low-temperature heat exchanger.

<Effects of the latent heat storage system and the latent heat storage method according to this embodiment>
In order to recover and utilize low-level waste heat such as distributed power sources, a compact latent heat storage system that operates at 100 ° C. or lower is necessary. Conventionally, as a system that operates in an operating region exceeding 100 ° C., research and development of a latent heat storage system using an “adsorption / desorption agent” such as silica gel has been actively conducted with the aim of hot water supply, heating, cooling, or drying. It was. However, the heat storage density is low and the heat storage tank is not sufficiently miniaturized, and the adsorption / desorption agent may be deteriorated or damaged due to repeated adsorption / desorption, and it has not been widely used.

  In this embodiment, by adopting an organic “absorption / desorption agent” instead of the “adsorption / desorption agent” as the heat storage agent, it is possible to reduce the size of the system and improve the durability of the heat storage agent. That is, the mass absorption / desorption amount of the organic sorbent / desorbent is as large as 2 to 3 times that of the conventional silica gel or the like, so that the size can be greatly reduced as compared with the conventional heat storage system.

  In addition, since the operating temperature (sorption / desorption temperature) of the sorbent / desorbent is as low as about 30 ° C to 100 ° C, it can be applied as the final stage of the thermal cascade of small to medium-sized distributed cogeneration systems for general household use. It becomes. It can be used in a wide range of fields such as cooling / heating, night heat storage, hot water supply, drying, dehumidification.

  Furthermore, by applying the water vapor transmission means, it is possible to make the medium supply to the sorbent / desorbent uniform, increase the heat and the moving speed of the medium, improve the volume utilization rate of the filled sorbent / desorbent, and further reduce the size. Is possible. For example, compared with a heat storage system using silica gel, a reduction of about 50% is expected.

<Necessity of heat / mass transfer speed improvement in latent heat storage system and latent heat storage method>
In the utilization of a latent heat storage system, how quickly heat and material can be taken in and out is an important matter, and this becomes a coupled problem of complicated heat and mass transfer phenomenon. Increasing the latent heat transfer rate in the sorption-desorption phenomenon of the sorbent / desorbent has the problem that when the sorbent / desorbent is used as a packed bed, the thermal conductivity and the resistance to material diffusion increase, resulting in an increase in the size of the system. .

  In order to solve this problem, a water vapor permeation means is introduced into the sorption / desorption tank, so that heat and mass transfer speed can be increased and uniform dispersion can be achieved. As a result, in the sorption step, it is possible to increase the amount of moisture sorbed per hour on the sorbent / desorbent by reducing the diffusion resistance and increasing the specific surface area. In the desorption process, the heat of the waste heat source is quickly transmitted to the desorption agent, so that the desorption time can be shortened and the size can be reduced. Such rapid heat and mass transfer can increase the heat transfer speed equivalent to or higher than that of a conventional compression heat pump system.

<Increase of latent heat storage density and prevention of deterioration>
Water is used for the working medium of the latent heat storage system according to the present embodiment. In order to improve the heat transfer speed during heat storage recovery, the water in the heat storage tank maintains a supercooled liquid phase by adding a freezing point depressant (antifreeze). For this reason, in order to increase the heat storage density, an emulsion in which the vicinity of the water freezing point becomes the freezing point is contained to improve the heat storage density.

  The operating environment of the latent heat storage system according to the present embodiment is pure water vapor (single component) as a working medium and a vacuum atmosphere. Therefore, when components other than moisture are mixed in the working medium, it adversely affects the deterioration of the sorbent / desorbent and the condensation heat transfer. Therefore, deterioration of the heat storage density can be prevented by using a water vapor transmission means that transmits only moisture.

<Use of latent heat storage system and latent heat storage method according to this embodiment>
The latent heat storage system using the sorption / desorption agent and water vapor transmission means according to the present embodiment is a low temperature region where the sorption / desorption temperature of the sorption / desorption agent ranges from about 30 ° C. to 100 ° C. It is a great advantage that the waste heat that has been used can be used. There are sufficient potential needs for the utilization of unused waste heat in the low temperature region in the consumer and industrial fields. For example, the following applications are conceivable.

  That is, for example, the use of cascades with small distributed power sources (solid polymer fuel cells, etc.) that will become more widespread in the future includes air conditioning (cooling and heating, dehumidification), nighttime heat storage, hot water supply, etc. for residential buildings, buildings, hospitals, etc. It is done. In addition, industrial applications include air conditioning in factories and offices, refrigeration, drying, and feedback of waste heat to the process. Furthermore, it can be expected to be used as a large-scale air-conditioning facility that uses the waste heat of cogeneration for district heating and cooling.

  In the above-described embodiment, the latent heat storage system using the “sorption / desorption tank” using the “sorption / desorption agent” has been described, but instead of the “sorption / desorption tank” using the “sorption / desorption tank”, “ An “adsorption / desorption tank” using an “adsorption / desorption agent” may be applied. Also in this case, a remarkable effect can be obtained by applying a water vapor transmission means, etc., as compared with the conventional system. In addition, the flow of water vapor, heat transfer, and the like in the adsorption process and the desorption process can be described in the same manner as in the sorption process and the desorption process.

  In the above-described embodiment, the sorption / desorption tube (adsorption / desorption tube) 11 ′ is disposed in the space of the introduction portion 15 with the outer tube, the heat exchanger 14, and the heat exchanger 14 as shown in FIG. Although a plurality of sorption / desorption tubes (adsorption / desorption tubes) 11 ′ composed of the inner tube of the desorbent 12 are arranged in the space of the water vapor introducing portion 15, the functions of the outer tube and the inner tube are reversed. At the same time, the inside of the inner tube may be a water vapor introducing portion, and the outside of the outer tube may be a heat circulation portion from the outside.

  That is, one or a plurality of sorption / desorption tubes (adsorption / desorption tubes) are provided in a portion where heat from the outside flows, and the sorption / desorption tubes (adsorption / desorption tubes) are sorption / desorption agents (adsorption / desorption) for sorption / desorption of water. An outer pipe composed of an inner part constituted by an agent) and an outer part constituted by a heat exchanger for exchanging heat at the time of the sorption / desorption with external heat, and steam introduction for introducing water vapor from the outside into the pipe As a part, a double pipe structure comprising an inner pipe which is a water vapor permeation means for condensing and vaporizing the water vapor introduced into the water vapor introduction part and supplying it to the adsorption / desorption agent (adsorption / desorption agent) substantially uniformly. It is good.

1 is a schematic configuration diagram of a latent heat storage system according to an embodiment of the present invention. It is a figure explaining the sorption process in the latent heat storage system which concerns on embodiment of this invention. It is a figure explaining the desorption process in the latent-heat thermal storage system which concerns on embodiment of this invention. The partial schematic external view (a) of the sorption / desorption tank of the latent heat storage system which concerns on embodiment of this invention, the figure (b) explaining the sorption process in an A direction arrow cross section, and the desorption process in an A direction arrow cross section FIG. It is the figure (b) explaining the sorption process in the partial schematic external view (a) of the thermal storage tank of the latent-heat thermal storage system which concerns on embodiment of this invention, and a B direction arrow cross section.

Explanation of symbols

1 Selective evaporation of moisture only 2 Water vapor flowing through piping 3 Uniform condensation 4 Evaporation 5 Uniform sorption

6 Desorption / evaporation 7 Water vapor flowing through the pipe 8 Condensation 9 Generation and movement of cold due to water evaporation

V ₁ , V ₃ , V ₅ , V ₇ External media
Medium after passing through V ₂ , V ₄ , V ₆ , V ₈ heat exchanger

DESCRIPTION OF SYMBOLS 10 Latent heat storage system 11 Sorptive / desorbable tank 11 'Sorptive / desorbed tube 12 Sorptive / desorbent 13 Water vapor permeation means 13a Base material part 13b Water vapor permeable film part 14 Heat exchanger 15 Water vapor introduction part 16 Evaporation part

DESCRIPTION OF SYMBOLS 18 Heat storage tank 18 'Water vapor transmission pipe 19 Cold storage agent 20 Water vapor transmission means 20a Base material part 20b Water vapor transmission membrane part 21 Heat exchanger (1st heat exchange means)
22 Heat exchanger (second heat exchange means)
23 Evaporating section 24 Condensing section

26 Steam piping 27a Selection valve 27b Selection valve 30 Vacuum pump

Claims (3)

A heat storage tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A regenerator that contains water, evaporates and condenses the water, a water vapor permeation means that permeates and evaporates only water from the regenerator, and first heat that exchanges heat during the evaporation with external heat. A heat storage tank, comprising: heat exchange means; and second heat exchange means for condensing water vapor from the outside and circulating it to the cold storage agent and exchanging heat at the time of condensation with external heat. A heat storage tank that exchanges water vapor with the outside and exchanges heat with external heat by means of heat exchange provided inside,
A regenerator stored in the heat storage tank, containing water, and evaporating and condensing the water;
First heat exchange means immersed in the cold storage agent and exchanging heat during the evaporation with external heat;
The heat storage tank is disposed in a space where the cold storage agent is not stored, and condenses the water vapor from the outside and circulates it to the cold storage agent, and exchanges heat at the time of the condensation with external heat. Heat exchange means;
Having one or more water vapor transmission tubes immersed in the cold storage agent,
The water vapor transmission pipe is a water vapor transmission means for allowing the outside of the pipe to face the cold storage agent and the inside of the pipe to communicate with the outside, and allowing only water from the cold storage agent outside the pipe to pass through and evaporate into the pipe. A heat storage tank characterized by being. In the heat storage tank according to claim 1 or 2,
The said cool storage agent contains an emulsion, The heat storage tank characterized by the above-mentioned.

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