JPS60140068A - Heat pump device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a heat pump device using metal hydrides.

(Prior Art) It is known that certain metals and alloys absorb hydrogen exothermically to form metal hydrides, and that these metal hydrides reversibly and endothermically release hydrogen. In recent years, various heat pump devices have been proposed that utilize the characteristics of such metal hydrides.

Most of these heat pump devices, in principle, use a pair of heat exchangers each forming a reaction vessel to handle metal hydrides having different hydrogen equilibrium decomposition pressures, as described in Japanese Patent Publication No. 55-35616, for example. These reaction vessels are connected with a hydrogen flow pipe to form a working pair, and the metal hydride in each reaction vessel is heated or cooled with a heating medium at a predetermined temperature for a certain period of time. A reaction in which hydrogen is endothermically released from a metal hydride in one reaction vessel of the pair, introduced into the other reaction vessel via a hydrogen flow pipe, and exothermically absorbed into the metal hydride in this reaction vessel. In this way, heat or cold at a predetermined temperature is extracted as output by utilizing the exothermic or endothermic reaction associated with absorption or release of hydrogen in the metal hydride.

FIG. 1 is an example of a cycle diagram showing the operation of the heat pump device as described above, in which the first metal hydride M
HI (hereinafter similarly expressed) is heated to high temperature TH with a heating medium at a predetermined temperature (point A), and MH2 is maintained at medium temperature TM with a heating medium at a predetermined temperature (point B), MHI and M
A pressure difference is created in the hydrogen equilibrium decomposition pressure of H2, hydrogen is endothermically released from MHI, this hydrogen is exothermically occluded in MH2, and then MHI is maintained at a mesotemperature TM and (
Point F), MH2 as a predetermined temperature TL (point E), M
A pressure difference of hydrogen equilibrium decomposition pressure is generated between H2 and MHI, hydrogen is released from M port 2, this hydrogen is stored in MHI, and the endothermic reaction of MH2 is utilized to generate a cold output at a temperature TL. This is what you get. After this, set the MHI to high 1T again.
Heating to H and holding MH2 at medium temperature TM completes the cycle.

In addition, instead of heating and cooling the metal hydride in each reaction vessel alternately as described above, hydrogen is supplied under pressure into the reaction vessel to absorb hydrogen, and then the pressure inside the reaction vessel is reduced to absorb hydrogen. It is also possible to obtain hot or cold output by alternately storing and desorbing hydrogen in each reaction vessel, as described in JP-A-51-82942, for example. Are known.

In such conventional heat pump devices, hydrogen transfer between reaction vessels due to absorption and desorption of hydrogen by metal hydrides is usually carried out as described in, for example, the above-mentioned Japanese Patent Application Laid-Open No. 51-82942. Regulated by a solenoid valve.

Therefore, in a typical conventional two-cylinder heat pump device, as shown in FIG.
A hydrogen flow pipe 13 and a second hydrogen flow pipe 14 are connected to each other, and each hydrogen flow pipe is equipped with control valves 15 and 16 that can be opened and closed.
At the same time, an MHI is attached to the first hydrogen flow pipe 13.
The second hydrogen flow pipe 14 is equipped with check valves 17 and 18 that allow only hydrogen transfer from MH2 to MHI, and the above control is performed according to the reaction cycle. The hydrogen transfer between containers is controlled by opening and closing valves.

The above-mentioned control valve is smaller and simpler than conventional ones,
In addition, solenoid valves are widely used because they are inexpensive, but as is well known, ordinary solenoid valves generally have the function of controlling the opening and closing of fluid flow to one side of a pipe. Therefore, it is necessary to install a check valve to block the flow in the opposite direction. Therefore, even in the simple so-called two-pump type heat pump device described above, it is necessary to install a solenoid valve in each hydrogen flow pipe in order to regulate the hydrogen transfer between the containers according to the reaction of the metal hydride in each reaction container. Therefore, in a practical 3-cylinder heat pump system or more, a solenoid valve and a check valve are required to regulate the hydrogen transfer between each reaction vessel. The number of check valves has become extremely large,
The device configuration becomes complicated, the reliability of the device becomes extremely poor, and the risk and likelihood of hydrogen leaking from the valve increases. On the other hand, if a high-grade control valve, such as an electric valve, is used, the risk of failure or hydrogen leakage may be eliminated to some extent, but the control system will be complicated and the device will be expensive.

(Object of the Invention) The present invention has been made to solve the above-mentioned problems in conventional heat pump devices, and has a simple device configuration by reducing the number of valves included in the device.
The purpose is to provide a heat pump device with high reliability.

(Summary of the Invention) The heat pump device of the present invention is characterized in that the (m+l)-th (1≦1)th (m+l) m≦n)
The hydrogen equilibrium decomposition pressure of the metal hydride in the m-th reaction vessel is higher than that of the metal hydride in the m-th reaction vessel, and the n-th reaction vessel and the first In a heat pump device which is connected to a th reaction vessel through a hydrogen flow pipe, (al) Hydrogen is allowed to flow through each hydrogen flow pipe only in the direction from the mth reaction vessel to the (m+1)th reaction vessel. A check valve is provided, and the mth reaction vessel is
Prohibiting the movement of hydrogen to the nth reaction vessel, and (bl) a hydrogen flow pipe connecting the nth reaction vessel and the first reaction vessel; A control valve capable of opening and closing is provided on at least one side of the hydrogen flow pipe connecting the The hydrogen is then introduced into the (m+1)th reaction vessel and absorbed into the metal hydride in this vessel. In this way, hydrogen is released from the metal hydride in the nth reaction vessel, and this hydrogen is introduced into the hydrogen flow. It was introduced into the first reaction vessel through a tube, and was absorbed by the metal hydride in this vessel, so that cold heat was obtained from the n-th reaction vessel, or warm heat was obtained from the first reaction vessel. Features.

(Structure of the Invention) The heat pump device of the present invention will be described below based on the drawings. In the following, as mentioned above, the m-th metal hydride is represented by MHm, and in the drawings it is represented by . m+1) is chosen to have a higher hydrogen equilibrium decomposition pressure than MHm in the operating temperature range of the device.

FIG. 3 shows an embodiment of the three-cylinder heat pump device of the present invention, which is suitable for obtaining cold output.

The first reaction vessel 21 filled with MHI and the second reaction vessel 22 filled with MH2 are connected by a hydrogen flow pipe 25 equipped with a check valve 24 that allows hydrogen to move only from the former to the latter direction. Similarly, the second reaction vessel 22 and the third reaction vessel 23 filled with MH3 are also connected by a hydrogen flow pipe 27 equipped with a check valve 26 that only allows hydrogen to move from the former to the latter. The third reaction vessel 23 and the first reaction vessel 21 are connected to a hydrogen flow pipe 29 equipped with a control valve, for example, a solenoid valve 28.
It is connected at

The operation of this device will be explained based on the cycle diagram shown in FIG. First, the solenoid valve 28 provided on the hydrogen flow pipe 29 connecting the first reaction vessel 21 and the third reaction vessel 23 is closed, and the MHI in the first reaction vessel 21 is heated to a predetermined high temperature. TH point A), second reaction vessel 22
While maintaining the MH2 within the specified medium temperature (point B), the MH
In order to maintain the hydrogen equilibrium decomposition pressure of MH3 higher than that of MH2, for example, MH3 in the third reaction vessel 23 is also heated to a medium temperature T.
By maintaining the pressure at M (point D), a pressure difference is generated between MHI and MH2 in the hydrogen equilibrium decomposition pressure, and MHI releases hydrogen endothermically, and this hydrogen passes through the hydrogen flow pipe 25 to the check valve 24. MH2 exothermically absorbs this hydrogen. In this reaction, as mentioned above, M
Since H3 is kept at an intermediate temperature and therefore the hydrogen equilibrium decomposition pressure is kept higher than that of MH2, MH2 to MH
Hydrogen transfer in three directions does not occur. Furthermore, since the solenoid valve 28 is closed, no hydrogen transfer from MHI to MH3 occurs during this time, regardless of the temperature of MH3. After this hydrogen transfer from A to B is completed, the MHI is cooled to intermediate temperature TM (point 0 F).

After completing this hydrogen transfer from A to B, the second reaction vessel 2
When MH2 in 2 is heated to a high temperature TH (point C) and a hydrogen equilibrium decomposition pressure difference is created between MH3 (point D), which is kept at a medium temperature TM as described above, MH2 decomposes hydrogen. The hydrogen is released endothermically, and this hydrogen passes through the hydrogen flow pipe 27 through the check valve 2G.
The hydrogen is introduced into the third reaction vessel through the hydrogen gas, and the hydrogen is endothermically occluded by MH3. Since the electromagnetic valve 28 is closed during this hydrogen transfer, hydrogen transfer from MH3 to MHI does not occur.

After this hydrogen transfer reaction from C to D is completed, when the solenoid valve 28 is opened, as mentioned above, since MHI is maintained at the intermediate temperature TM (point F), the hydrogen equilibrium decomposition pressure is created between MH3 and MHI. A pressure difference of 2 is generated, and MH3 endothermically releases hydrogen at low temperature TL (point E). This hydrogen flow pipe 29 is led to the first reaction vessel via a solenoid valve 28, where MHI absorbs this hydrogen. occludes exothermically (point F).

The cycle is then completed by returning MHI to temperature TH and MH2 and MHI13 to temperature TM.

Therefore, the above heat pump device uses a high temperature TH heat source to obtain low temperature TL cold heat as output, and can be used for air conditioning, for example, but in the case of a conventional two-cylinder type device, A-B -E'-F cycle, whereas according to the apparatus of the present invention, A-B-+C
Since the cycle of -+D→E-+F is performed, a cold output at a lower temperature can be obtained.

FIG. 5 shows a multi-cylinder heat pump device consisting of n cylinders instead of the three-cylinder type described above, and the m-th reaction vessel and the (m+1)-th reaction vessel are arranged in the direction from the former to the latter reaction vessel. The n-th reaction vessel and the first reaction vessel are connected by a hydrogen circulation pipe 32 equipped with a check valve 31 that only allows hydrogen transfer to the hydrogen flow pipe 34 equipped with a solenoid valve 33. It is connected at

The operation of such a multi-cylinder heat pump device is similar to that described above, and as shown in the cycle diagram of Fig. 6, hydrogen is transferred from the MHI to the next stage having a higher hydrogen equilibrium decomposition pressure. After hydrogen transfer from MH(n-1) to MHn, hydrogen transfer from MHn to MHI completes the cycle, and hydrogen storage in MHn is completed. Cold output is obtained from the reaction. Incidentally, the more stages the metal hydride is used, the lower the temperature of the cold output can be obtained.

FIG. 7 shows an embodiment of the three-cylinder heat pump device of the present invention, which is suitable for obtaining thermal output. A first reaction vessel 41 filled with MHI and a second reaction vessel 42 filled with MH2 are connected to a hydrogen flow pipe 46 equipped with a check valve 44 and a solenoid valve 45 that only allow hydrogen movement from the former to the latter. Similarly, the second reaction vessel 42 and the third reaction vessel 43 filled with MH3 are connected by a hydrogen flow pipe 48 equipped with a check valve 47 that only allows hydrogen to move from the former to the latter. At the same time, the third reaction vessel and the first reaction vessel are connected by a hydrogen flow pipe 49 without a valve.

The operation of this device is as shown in the Seikle diagram shown in FIG. points B and D) and M, respectively.
Due to the difference in hydrogen equilibrium decomposition pressure between HI and MH2,
MHI emits hydrogen endothermically, and this hydrogen is led to second reaction vessel 42 through hydrogen flow pipe 46 through electromagnetic valve 45 and check valve 44, and MH2 absorbs this hydrogen exothermically. During this reaction, as mentioned above, MH3 is also kept at a low temperature TL and therefore the hydrogen equilibrium decomposition pressure is kept higher than that of MH2, so no hydrogen transfer from MH2 to MH3 occurs. Also, during this period, MH3 has a higher hydrogen equilibrium decomposition pressure than MHI and is in a state after hydrogen has been released, so MH3 and MHI are connected to the hydrogen flow pipe 49 without a valve.
However, no hydrogen transfer occurs through this hydrogen flow pipe. After completion of this reaction, the MHI is heated to high temperature TH.

4 After the hydrogen transfer from this person to B is completed, MH2 is heated to medium temperature TM.
When a pressure difference is created in the hydrogen equilibrium decomposition pressure between MH3 (point D) kept at low temperature T L as described above, MH2 releases hydrogen endothermically, This hydrogen is led to the third reaction vessel through the hydrogen flow pipe 48 and the check valve 47, where the hydrogen is endothermically occluded by MH3. During this hydrogen transfer from C to D, regardless of the temperature of MHI, the check valve 44 on the hydrogen flow pipe 44
Hydrogen transfer from 2 to MHI is blocked. Also, MHI
is kept at a temperature T) (higher than that of MH3, and the hydrogen equilibrium decomposition pressure is kept higher than that of MH3, so MH
Hydrogen transfer from 3 to MHI also does not occur.

After this reaction is completed, the solenoid valve 45 is closed and MH3 is heated to a medium temperature T.
MHI at temperature T H after heating to M and releasing MH3 and hydrogen.
When a pressure difference is created in the hydrogen equilibrium decomposition pressure between MH3 and
releases hydrogen endothermically and passes through the hydrogen flow pipe 49 to the MHI.
MHI absorbs this hydrogen exothermically.

During this time, hydrogen transfer from MH35 to MHI is prohibited by check valve 47, and since solenoid valve 45 is closed, hydrogen transfer from MHI to MH
No hydrogen transfer to 2 occurs. After this, change the MHI to the temperature T
The cycle is completed by returning MH2 and MH3 to temperature TL.

Therefore, according to the heat pump device described above, thermal heat at a predetermined temperature TH can be obtained as an output using a medium-temperature heat medium as a driving heat source, but in particular, in the case of a conventional two-cylinder heat pump device, C→D -+E'→F cycle, whereas according to the apparatus of the present invention, A→B
Since the cycle of →C→D→E→F is performed, a higher temperature thermal output can be obtained.

FIG. 9 shows a multi-cylinder heat pump device consisting of n cylinders instead of the three-cylinder type described above, and the (m-1)th reaction vessel and the m-th reaction vessel are used for the reaction from the former to the latter. The n-th reaction container and the first reaction container are connected by a hydrogen flow pipe 52 equipped with a check valve 51 that allows hydrogen to flow in the direction of the container, and a hydrogen flow pipe 53 having no valve is connected to the n-th reaction container and the first reaction container. At the same time as connecting 6, the first and second reaction vessels are
In addition to the above-mentioned check valve 44, a hydrogen flow pipe 46 equipped with an electromagnetic valve 45 is connected.

The operation of such a multi-cylinder heat pump device is similar to that described above, and as shown in the cycle diagram of FIG. 10, hydrogen is sequentially transferred from MHI to metal hydride with higher hydrogen equilibrium decomposition pressure, From MH(n-1) to Ml(
After hydrogen transfer to n, from this M Hn to M H
Hydrogen transfer to I completes the cycle.

(Effect of the invention) As described above, in the heat pump device of the present invention,
Metal hydrides having different hydrogen equilibrium decomposition pressures in a predetermined operating temperature range are connected in such a way that their hydrogen equilibrium decomposition pressures increase in sequence, and hydrogen is released from the metal hydride in the first reaction vessel. Hydrogen is sequentially transferred to the metal hydride in the next stage where the hydrogen equilibrium decomposition pressure is higher, and finally from the final stage reaction vessel to the first reaction vessel, so compared to a two-cylinder heat pump system, In addition, the number of valves included in the device was minimized by taking advantage of the characteristics of metal hydride reactions, which simplified the device configuration and made it easier to operate the device. In addition to being able to reduce the damage, the reliability of the device is also significantly improved. Also, the risk of hydrogen leakage is greatly reduced.

[Brief explanation of drawings]

Fig. 1 is a cycle diagram for explaining the operation of a conventional two-cylinder heat pump device, Fig. 2 is a device configuration diagram showing a typical example of a two-cylinder heat pump device, and Fig. 3 is a diagram of a heat pump device of the present invention. Device configuration diagram showing one embodiment, No. 4
The figure is a cycle diagram explaining the operation of the device in Figure 3, Figure 5 is a device configuration diagram showing a multi-cylinder heat pump device corresponding to Figure 3, and Figure 6 is a cycle diagram showing its operation. 7 is a device configuration diagram showing another embodiment of the heat pump device of the present invention, FIG. 8 is a cycle diagram for explaining the operation of the device shown in FIG. 7, and FIG. 9 is a diagram similar to that shown in FIG. 6. Device configuration diagram showing a multi-cylinder heat pump device corresponding to
Figure 0 is an 8-cycle diagram showing its operation. 21.22.23...Reaction container, 24.26...Check valve, 25.27.29...Hydrogen flow pipe, 28...
Solenoid valve, 31... Check valve, 32.34... Hydrogen flow pipe, 33... Solenoid valve, 41.42.43... Reaction vessel, 44.47... Check valve, 45 ...Solenoid valve, 48
．． 49...Hydrogen flow pipe, 51.54...Check valve, 5
2.53... Hydrogen flow pipe, 55... Solenoid valve. Patent applicant Sekisui Chemical Co., Ltd. Representative Mototoshi Fujinuma 9 Figure 1 HTMTL 1/T Figure 2 Bore dη

Claims (1)

[Claims] (1) N reaction vessels each filled with n types (n≧3) of metal hydrides having different hydrogen equilibrium decomposition pressures are placed in the (m+1)th (1≦m≦n) reaction vessel. The n-th reaction vessel and the first reaction vessel are connected by hydrogen flow pipes so that the hydrogen equilibrium decomposition pressure of the metal hydride is higher than that of the metal hydride in the m-th reaction vessel. (a) Each hydrogen flow pipe is provided with a check valve that allows hydrogen to flow only from the mth reaction vessel to the (m+1)th reaction vessel. from the (m+1)th reaction vessel to the mth
[b] A hydrogen flow pipe connecting the nth reaction vessel and the first reaction vessel, and a hydrogen flow pipe connecting the first reaction vessel and the second reaction vessel; A control valve that can be opened and closed is provided on at least one side of the hydrogen flow pipe connecting the container, and hydrogen is released from the metal hydride in the m-th reaction container in C1 sequence, and this hydrogen is passed through the check valve. is introduced into the (m+1)th reaction vessel through which it is absorbed into the metal hydride in this vessel. In this way, hydrogen is released from the metal hydride in the nth reaction vessel, and this hydrogen is converted into hydrogen. It is led to the first reaction vessel via a flow pipe, is absorbed by the metal hydride in this vessel, and cold heat is obtained from the n-th reaction vessel, or warm heat is obtained from the first reaction vessel. A heat pump device featuring: