A large temperature difference heat storage and heat supply system

Abstract

The present invention relates to a large temperature difference heat storage and heat supply system, which includes an energy station, an end heat exchange station and a user end; wherein the energy station includes a heat storage body, an absorption heat pump and a first heat exchanger, and the water discharged from the heat storage body returns to the heat storage body after releasing heat through the absorption heat pump and the first heat exchanger; the end heat exchange station includes a second heat exchanger and a first compression heat pump, and the return water of the end heat exchange station absorbs the heat released by the energy station and then is sent back to the end heat exchange station again, and releases heat and cools down in the end heat exchange station; the return water of the user end absorbs heat and is heated up respectively through the second heat exchanger and the condenser of the first compression heat pump to form hot water for supplying the user end. The present invention uses high-temperature hot water as the driving force, and the high-temperature hot water sequentially passes through the generator of the absorption heat pump, the first heat exchanger and the evaporator of the absorption heat pump, thereby reducing the return water temperature of heat storage and heat release. The return water temperature is reduced to 0°C or even becomes ice slurry, and the heat storage capacity is increased by more than 2 times compared with the current heat storage technology.

Description

Technical Field

[0001] The present invention belongs to the field of energy, and particularly relates to a large temperature difference heat storage and heat supply system. Background Art

[0002] In the central heating system, the heating method of district boiler rooms widely used is gradually cancelled due to high carbon emissions and high operating costs, resulting in a heat source gap problem. In this context, the industry has proposed a technical solution of cross-season heat storage. However, the return water temperature of the heat storage tank is relatively high, and the heat storage and heat release temperature difference is generally less than 50°C, resulting in a low heat storage capacity per unit heat storage body and a very large volume of the heat storage body, increasing the investment cost. In the prior art, a two-stage electric heat pump is proposed to cool the heat storage hot water. This technology can cool the heat storage hot water to about 20°C, achieving a heat storage and release temperature difference of about 70°C. However, this technology consumes a large amount of electricity, and the heat storage body is still relatively large, and the economy of the system still needs to be improved. Summary of the Invention

[0003] In order to solve the above problems, the purpose of the present invention is to provide a large temperature difference heat storage and heat supply system. By using the heat storage high-temperature hot water itself as the driving force of the absorption heat pump, large temperature difference heat storage can be achieved without consuming or consuming less electricity.

[0004] In the first aspect of the present invention, a large temperature difference heat storage and heat supply system is provided, including an energy station, a terminal heat exchange station, and a user end;

[0005] The energy station is used to release heat by using hot water, and the released heat is absorbed by the terminal heat exchange station;

[0006] After the return water of the terminal heat exchange station absorbs the heat released by the energy station, it is sent back to the terminal heat exchange station again, and releases heat and cools down in the terminal heat exchange station;

[0007] After the return water of the user end absorbs the heat released by the water in the terminal heat exchange station, it is heated to form hot water to supply the user end.

[0008] Further, the energy station includes a heat storage body, an absorption heat pump, and a first heat exchanger. The outlet water of the heat storage body sequentially passes through the generator of the absorption heat pump for cooling and the first heat exchanger for heat release, and then passes through the evaporator of the absorption heat pump for heat release again and then returns to the heat storage body.

[0009] Further, the terminal heat exchange station includes a second heat exchanger and a first compression heat pump;

[0010] The return water of the terminal heat exchange station is divided into two paths. The first path absorbs heat and is heated up through the first heat exchanger, and the second path absorbs heat and is heated up through the absorption heat pump. The hot water heated up by the two paths is sent back to the terminal heat exchange station again;

[0011] The return water of the user side is heated by absorbing heat through the second heat exchanger and the condenser of the first compression heat pump respectively, and then forms hot water to supply the user side.

[0012] Furthermore, it also includes a second compression heat pump;

[0013] The water flowing out of the heat storage body is cooled by passing through the generator of the absorption heat pump in sequence and releases heat through the first heat exchanger, and then enters the evaporator of the second compression heat pump to release heat again. The water flowing out after releasing heat through the evaporator of the second compression heat pump releases heat again through the evaporator of the absorption heat pump and then flows back to the heat storage body;

[0014] The second return water of the terminal heat exchange station is heated by absorbing heat through the absorption heat pump and then further heated by absorbing heat through the condenser of the second compression heat pump, and then sent to the terminal heat exchange station.

[0015] Furthermore, it also includes a third compression heat pump;

[0016] The second path of the return water of the terminal heat exchange station is heated by absorbing heat through the condenser of the third compression heat pump and then further heated by absorbing heat through the condenser of the second compression heat pump, and then sent to the terminal heat exchange station; or the second path of the return water of the terminal heat exchange station is divided into two paths, one path is heated by absorbing heat through the condenser of the third compression heat pump and then sent to the terminal heat exchange station, and the other path is heated by absorbing heat through the condenser of the second compression heat pump and then sent to the terminal heat exchange station;

[0017] The water flowing out after releasing heat through the evaporator of the third compression heat pump absorbs heat through the condenser of the absorption heat pump and becomes hot water, and this path of hot water enters the evaporator of the third compression heat pump again.

[0018] Furthermore, it also includes a second compression heat pump;

[0019] The return water of the terminal heat exchange station is divided into three paths, and the third path is heated by absorbing heat through the condenser of the second compression heat pump and then sent back to the terminal heat exchange station;

[0020] The water flowing out of the heat storage body is cooled by passing through the generator of the absorption heat pump in sequence and releases heat through the first heat exchanger, and then enters the evaporator of the second compression heat pump to release heat again. The water flowing out after releasing heat through the evaporator of the second compression heat pump releases heat again through the evaporator of the absorption heat pump and then flows back to the heat storage body.

[0021] Furthermore, it also includes a third compression heat pump;

[0022] Among them, the second return water of the terminal heat exchange station becomes high-temperature hot water through the absorption heat pump and flows out of the absorption heat pump. The hot water flowing out of the absorption heat pump is divided into two paths. One path directly enters the condenser of the third compression heat pump, and after absorbing heat and rising in temperature in the condenser of the third compression heat pump, it flows back into the terminal heat exchange station again; the other path enters the evaporator of the third compression heat pump to release heat and cool down, and then enters the absorption heat pump again to absorb heat.

[0023] Further, the terminal heat exchange station includes a first compression heat pump;

[0024] The return water of the user side is divided into two paths. The first return water of the user side is cooled by the first compression heat pump. The cooled outlet water is divided into two paths. One path directly absorbs heat and rises in temperature through the first heat exchanger to form hot water for supplying the user side, and the other path absorbs heat and rises in temperature through the condenser of the absorption heat pump to form hot water for supplying the user side;

[0025] The second return water of the user side passes through the first compression heat pump, and after absorbing heat and rising in temperature in the first compression heat pump, it forms hot water for supplying the user side.

[0026] As can be seen from the above technical solutions, a large-temperature-difference heat storage and heat supply system provided by the present invention has the following beneficial effects:

[0027] The present invention utilizes the driving ability of high-temperature hot water, which can effectively reduce power consumption and increase the economic efficiency of system operation;

[0028] The present invention uses high-temperature hot water as the driving force. The high-temperature hot water sequentially passes through the generator of the absorption heat pump, the first heat exchanger and the evaporator of the absorption heat pump, thereby reducing the return water temperature of heat storage and heat release. The return water temperature is reduced to 0 °C or even becomes ice slurry, and the heat storage capacity is increased by more than 2 times compared with the current heat storage technology. Description of the Drawings

[0029] Figure 1 It is a schematic structural diagram of a large-temperature-difference heat storage and heat supply system according to Embodiment 1 of the present invention;

[0030] Figure 2 It is a schematic structural diagram of a large-temperature-difference heat storage and heat supply system according to Embodiment 2 of the present invention;

[0031] Figure 3 It is a schematic structural diagram of a large-temperature-difference heat storage and heat supply system according to Embodiment 3 of the present invention;

[0032] Figure 4 It is a schematic structural diagram of a large-temperature-difference heat storage and heat supply system according to Embodiments 4 and 5 of the present invention;

[0033] Figure 5 It is a schematic structural diagram of a large-temperature-difference heat storage and heat supply system according to Embodiment 6 of the present invention;

[0034] Figure 6 This is a schematic structural diagram of a specific example of a large temperature difference heat storage and heat supply system according to an embodiment of the present invention.

[0035] The reference numerals in the figure are: heat storage body 1, absorption heat pump 2, first heat exchanger 3, second heat exchanger 4, first compression heat pump 5, second compression heat pump 6, and third compression heat pump 7. Detailed implementation mode

[0036] In order to better understand the purpose, structure and function of the present invention, a large temperature difference heat storage and heat supply system of the present invention will be further described in detail below.

[0037] Embodiment 1:

[0038] As Figure 1 shown, a large temperature difference heat storage and heat supply system includes an energy station, a terminal heat exchange station and a user end;

[0039] Among them, the energy station is used to release heat by using hot water, and the released heat is absorbed by the terminal heat exchange station;

[0040] The return water of the terminal heat exchange station absorbs the heat released by the energy station and then is sent back to the terminal heat exchange station again, and releases heat and cools down in the terminal heat exchange station;

[0041] The return water of the user end absorbs the heat released by the water in the terminal heat exchange station and then is heated to form hot water for supplying the user end.

[0042] Specifically, the energy station includes a heat storage body 1, an absorption heat pump 2 and a first heat exchanger 3, and the heat storage body 1 is used to store low-temperature water and heat the low-temperature water into high-temperature water with a higher temperature. The high-temperature water flowing out of the heat storage body 1 sequentially passes through the generator of the absorption heat pump 2 to drive the operation of the absorption heat pump 2. The operation of the absorption heat pump 2 causes the high-temperature water to cool down. The cooled high-temperature water releases heat through the first heat exchanger 3 and then passes through the evaporator of the absorption heat pump 2 again. The water releases heat in the evaporator of the absorption heat pump 2 and then forms low-temperature water or ice slurry again and flows back to the heat storage body 1;

[0043] The terminal heat exchange station specifically includes a second heat exchanger 4 and a first compression heat pump 5. Among them, the return water of the terminal heat exchange station is divided into two paths. The first path absorbs heat and increases in temperature through the first heat exchanger 3, and the second path absorbs heat and increases in temperature through the absorption heat pump 2. The return water after absorbing heat and increasing in temperature in both paths is sent back to the terminal heat exchange station again. Specifically, the return water of the first compression heat pump 5 is divided into two paths. The first path absorbs heat and increases in temperature through the first heat exchanger 3 and then flows into the second heat exchanger 4. The second path absorbs heat and increases in temperature through the absorption heat pump 2 and then flows into the second heat exchanger 4. The hot water entering the second heat exchanger 4 through the first path and the second path loses heat and decreases in temperature in the second heat exchanger 4 and then enters the first compression heat pump 5 again. After releasing heat and decreasing in temperature in the evaporator of the first compression heat pump 5, it flows out of the first compression heat pump 5 to obtain the return water of the first compression heat pump 5. And the return water of the user side is also divided into two paths. One path absorbs the temperature lost by the hot water in the second heat exchanger 4 and becomes high-temperature hot water to supply the user, and the other path absorbs heat and increases in temperature through the condenser of the first compression heat pump 5 and becomes high-temperature hot water to supply the user side.

[0044] Therefore, in this embodiment, the water of the user side is separated by the terminal heat exchanger and will not enter the circulating water between the terminal heat exchange station and the energy station, thus ensuring the water quality of the user side and avoiding the situation of the user side water being polluted.

[0045] Embodiment 2:

[0046] On the basis of Embodiment 1, this embodiment further includes a second compression heat pump 6, as Figure 2 shown; in this embodiment, the water flowing out of the heat storage body 1 sequentially passes through the generator of the absorption heat pump 2 to decrease in temperature and the first heat exchanger 3 to release heat, and then enters the evaporator of the second compression heat pump 6 to release heat again. The water flowing out of the evaporator of the second compression heat pump 6 releases heat again through the evaporator of the absorption heat pump 2 and then flows back to the heat storage body 1.

[0047] The return water of the terminal heat exchange station is also divided into two paths: the first path absorbs heat and increases in temperature through the first heat exchanger 3, and the second path absorbs heat and increases in temperature through the absorption heat pump 2 and then absorbs heat and increases in temperature again through the condenser of the second compression heat pump 6. The hot water after absorbing heat and increasing in temperature in both paths is sent to the terminal heat exchange station together. Specifically, the first path absorbs heat and increases in temperature through the first heat exchanger 3 and then flows into the second heat exchanger 4. The second path of return water absorbs heat and increases in temperature through the absorption heat pump 2 and then absorbs heat and increases in temperature again through the condenser of the second compression heat pump 6 and then flows into the second heat exchanger 4. The hot water entering the second heat exchanger 4 through the first path and the second path also loses heat and decreases in temperature in the second heat exchanger 4 and then enters the first compression heat pump 5 again; the return water of the user side is heated and formed into hot water to supply the user in the same path as in Embodiment 1.

[0048] Embodiment 3:

[0049] The second path of the return water of the terminal heat exchange station is heated by absorbing heat through the condenser of the third compression heat pump 7 and then further heated by absorbing heat through the condenser of the second compression heat pump 6, and then sent into the terminal heat exchange station;

[0050] On the basis of Embodiment 2, this embodiment further includes a third compression heat pump 7. As Figure 3 shown: In Embodiment 2, it is introduced that the return water of the terminal heat exchange station is divided into two paths. The first path of the return water of the terminal heat exchange station in this embodiment has the same flow path as the first path of the return water in Embodiment 2. The difference between this embodiment and Embodiment 2 is that: in this embodiment, the second path of the return water of the terminal heat exchange station is heated by absorbing heat through the condenser of the third compression heat pump 7 and then further heated by absorbing heat through the condenser of the second compression heat pump 6. The two paths of hot water after heat absorption and temperature rise are sent into the terminal heat exchange station together, or the second path of the return water of the terminal heat exchange station is divided into two paths. One path is heated by absorbing heat through the condenser of the third compression heat pump 7 and then sent into the terminal heat exchange station, and the other path is heated by absorbing heat through the condenser of the second compression heat pump 6 and then sent into the terminal heat exchange station; In addition, the water discharged after releasing heat through the evaporator of the third compression heat pump 7 becomes hot water after absorbing heat through the condenser of the absorption heat pump 2, and this hot water enters the evaporator of the third compression heat pump 7 again, forming a cycle between the evaporator of the third compression heat pump 7 and the condenser of the absorption heat pump 2 through this path; The return water of the user end is heated along the same path as in Embodiment 1 to form hot water and supply it to the user.

[0051] Embodiment 4:

[0052] On the basis of Embodiment 1, as Figure 4 shown, this embodiment further includes a second compression heat pump 6; After adding the second compression heat pump 6 in this embodiment, the return water of the terminal heat exchange station is divided into three paths. The first path and the second path are the same as the first path and the second path in Embodiment 1 respectively. The third path of the return water is heated by absorbing heat through the condenser of the second compression heat pump 6 and becomes hot water, and the obtained hot water is sent into the terminal heat exchange station again; In addition, due to the addition of the second compression heat pump 6, the water path of the energy station part has changed. In this embodiment, the water path of the energy station part is specifically: the water discharged from the heat storage body 1 is cooled by passing through the generator of the absorption heat pump 2 and releases heat through the first heat exchanger 3, and then enters the evaporator of the second compression heat pump 6 to release heat again. The water discharged after releasing heat through the evaporator of the second compression heat pump 6 releases heat again through the evaporator of the absorption heat pump 2 and then flows back to the heat storage body 1; The flow path of the return water of the user end in this embodiment is the same as that in Embodiment 4.

[0053] Embodiment 5:

[0054] On the basis of Embodiment 4, as Figure 4As shown in the figure, the third compression heat pump 7 is further included in this embodiment. Due to the addition of the third compression heat pump 7 in this embodiment, the flow path of the second return water of the terminal heat exchange station has changed. In this embodiment, the second return water of the terminal heat exchange station becomes high-temperature hot water after absorbing heat in the absorption heat pump 2 and flows out of the absorption heat pump 2. The hot water flowing out of the absorption heat pump 2 is divided into two paths again. The first path directly enters the condenser of the third compression heat pump 7, and after absorbing heat and rising in temperature in the condenser of the third compression heat pump 7, it flows back into the terminal heat exchange station again. The second path enters the evaporator of the third compression heat pump 7 to release heat and cool down, and then enters the absorption heat pump 2 again to absorb heat. The water flow path of the energy station part and the water flow path of the user-side return water are the same as those in Embodiment 4.

[0055] Embodiment 6:

[0056] As Figure 5 shown, a large temperature difference heat storage and heat supply system includes an energy station, a user side, and a first compression heat pump 5;

[0057] Among them, the energy station includes a heat storage body 1, an absorption heat pump 2, and a first heat exchanger 3. The heat storage body 1 is used to store low-temperature water and heat the low-temperature water into high-temperature water with a higher temperature. The high-temperature water flowing out of the heat storage body 1 sequentially passes through the generator of the absorption heat pump 2 to drive the absorption heat pump 2 to operate. The operation of the absorption heat pump 2 causes the high-temperature water to cool down. The cooled high-temperature water releases heat through the first heat exchanger 3 and then passes through the evaporator of the absorption heat pump 2 again. The water releases heat in the evaporator of the absorption heat pump 2 and then forms low-temperature water or ice slurry and flows back to the heat storage body 1;

[0058] The return water of the user side is divided into two paths. The first return water of the user side is cooled by the first compression heat pump 5. The cooled outlet water is divided into two paths to absorb heat and rise in temperature and then supply to the user side. One path directly absorbs heat and rises in temperature through the first heat exchanger 3 to form hot water and supply to the user side, and the other path absorbs heat and rises in temperature through the condenser of the absorption heat pump 2 to form hot water and supply to the user side;

[0059] The second return water of the user side passes through the first compression heat pump 5, absorbs heat and rises in temperature in the first compression heat pump 5 to form hot water and supply to the user side.

[0060] To facilitate understanding the invention purpose of the above embodiments of the present invention, a specific example is described below.

[0061] As Figure 6As shown, the outlet water temperature of the heat storage body 1 is 90°C. After entering the generator of the absorption heat pump 2 and cooling down to 60°C, it enters the first heat exchanger 3 to further release heat until it reaches 10°C, and then enters the evaporator of the second compression heat pump 6 to further cool down to 5°C. After that, it enters the evaporator of the absorption heat pump 2 again to cool down and then returns to the heat storage body 1. Entering the evaporator of the absorption heat pump 2 again can cool it down to a slush state where part of it freezes; the return water temperature of the evaporator of the first compression heat pump 5 is 5°C. One path enters the heat exchanger to absorb heat and raise the temperature to 55°C; the other path enters the condenser of the compression heat pump to absorb heat and raise the temperature to 46°C. The water at 46°C then enters the condenser of the compression heat pump to continue absorbing heat and raise the temperature to 55°C. The two paths of warm water at 55°C are mixed and then enter the second heat exchanger 4. The return water at the user end becomes warm water for user use by absorbing the heat released from the 55°C warm water when it loses temperature.

[0062] It should be noted that unless otherwise specified, the technical terms or scientific terms used in this application should have the ordinary meanings understood by those skilled in the art to which this invention belongs.

[0063] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered by the scope of the claims and the specification of the present invention. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed in the text, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A large temperature difference heat storage and heat supply system, characterized in that, It includes an energy station, a terminal heat exchange station, and a user end; The energy station is used to release heat by using hot water, and the released heat is absorbed by the terminal heat exchange station; The return water of the terminal heat exchange station absorbs the heat released by the energy station and then is sent back to the terminal heat exchange station again, and releases heat and cools down in the terminal heat exchange station; The return water of the user end absorbs the heat released by the water in the terminal heat exchange station and then heats up to form hot water to supply the user end; The energy station includes a heat storage body (1), an absorption heat pump (2), and a first heat exchanger (3). The hot water of the heat storage body (1) sequentially passes through the generator of the absorption heat pump (2) to cool down and the first heat exchanger (3) to release heat, and then passes through the evaporator of the absorption heat pump (2) to release heat again and then flows back to the heat storage body (1); The return water of the terminal heat exchange station is divided into two paths. The first path absorbs heat and heats up through the first heat exchanger (3), and the second path absorbs heat and heats up through the absorption heat pump (2). The hot water after the two paths absorb heat and heat up is sent back to the terminal heat exchange station again; It also includes a third compression heat pump (7). The second path of the return water of the terminal heat exchange station becomes high-temperature hot water through the absorption heat pump (2) and flows out of the absorption heat pump (2). The hot water flowing out of the absorption heat pump (2) is divided into two paths. One path directly enters the condenser of the third compression heat pump (7), absorbs heat and heats up in the condenser of the third compression heat pump (7) and then flows back into the terminal heat exchange station again; the other path enters the evaporator of the third compression heat pump (7) to release heat and cool down and then enters the absorption heat pump (2) to absorb heat again.

2. The large temperature difference heat storage and heat supply system according to claim 1, characterized in that, The terminal heat exchange station includes a second heat exchanger (4) and a first compression heat pump (5); The return water of the user end absorbs heat and heats up respectively through the second heat exchanger (4) and the condenser of the first compression heat pump (5) to form hot water to supply the user end.

3. The large temperature difference heat storage and heat supply system according to claim 2, characterized in that, It also includes a second compression heat pump (6); The water flowing out of the heat storage body (1) sequentially passes through the generator of the absorption heat pump (2) to cool down and the first heat exchanger (3) to release heat, and then enters the evaporator of the second compression heat pump (6) to release heat. The water flowing out of the evaporator of the second compression heat pump (6) passes through the evaporator of the absorption heat pump (2) to release heat again and then flows back to the heat storage body; The second path of the return water of the terminal heat exchange station absorbs heat and heats up through the absorption heat pump (2) and then absorbs heat and heats up again through the condenser of the second compression heat pump (6) and is sent into the terminal heat exchange station.

4. The large temperature difference heat storage and heat supply system according to claim 2, characterized in that, It also includes a second compression heat pump (6); The return water of the terminal heat exchange station is divided into three paths. The third path absorbs heat and heats up through the condenser of the second compression heat pump (6) and then is sent back to the terminal heat exchange station again; The water flowing out of the heat storage body (1) sequentially passes through the generator of the absorption heat pump (2) to cool down and the first heat exchanger (3) to release heat, and then enters the evaporator of the second compression heat pump (6) to release heat. The water flowing out of the evaporator of the second compression heat pump (6) passes through the evaporator of the absorption heat pump (2) to release heat again and then flows back to the heat storage body.

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