Geothermal source heat exchanger

Abstract

This invention provides a geothermal heat exchanger, relating to the field of geothermal source applications. The geothermal heat exchanger includes a heat exchange tube bent into a "U" shape for heat exchange. The heat exchange tube is divided into an inlet pipe and an outlet pipe. A cutoff unit is installed between the inlet and outlet pipes to interrupt the circulation of the lower heat exchange tube. The cutoff unit connects the inlet and outlet pipes, and multiple cutoff units are evenly spaced between the inlet and outlet pipes. When a leak occurs in the heat exchange tube, this geothermal heat exchanger temporarily connects each cutoff unit sequentially, preventing the heat exchange tube below from entering the circulation, thus allowing the leak point to be located. After locating the leak, the cutoff unit closest to the leak point is permanently connected, solving the problems of difficulty in locating leaks and the difficulty in repairing damaged geothermal heat exchangers in the prior art.

Description

Technical Field

[0001] This invention relates to the field of geothermal source applications, specifically to geothermal source heat exchangers. Background Technology

[0002] Geothermal heat pump systems, also known as ground source heat pumps, use geothermal energy (soil, groundwater, surface water, low-temperature geothermal water, and tailwater) as the cooling source for summer cooling and the low-temperature heat source for winter heating. They simultaneously provide heating, cooling, and domestic hot water. This system replaces the traditional method of using chillers and boilers for air conditioning, heating, and hot water supply. It is an effective way to improve the urban atmospheric environment and save energy, and represents a new development direction for the utilization of geothermal energy in China.

[0003] (CN209371569U) A ground source heat pump well and a ground source heat pump system, wherein the ground source heat pump well includes a well pit and heat exchange pipes; the depth of the well pit is 600-4000m; the heat exchange pipes include an inlet pipe, a return pipe, a constant pressure water injection device and a well body; the well body is set inside the well pit; the first end of the inlet pipe and the first end of the return pipe are both connected to the heat pump unit; the second end of the inlet pipe and the second end of the return pipe extend into the well body; a filling medium is also provided between the well pit and the well body; the constant pressure water injection device is set between the well pit and the well body to inject water into the space between the well pit and the well body to improve the thermal conductivity of the filling medium.

[0004] This technical solution utilizes ground-source heat pump wells and systems capable of extracting medium-deep geothermal energy, with a usable heat capacity of 150-200 W / m³. The heat utilization rate is high, and the heat source is stable, thus reducing the number of wells required. The solution also specifies the placement of pipelines into the well pit and filling it with a filling medium.

[0005] Existing patent (CN112524827A) discloses an installation structure and method for a ground source heat exchanger. This installation structure includes a buried pipe heat exchanger, a horizontal connecting pipe, and a cantilever support. The buried pipe heat exchanger is located on the outside of the building. The horizontal connecting pipe is connected to the buried pipe heat exchanger and extends horizontally from the outside of the building. The cantilever support is installed horizontally on the outside of the building. When the horizontal connecting pipe connected to the buried pipe heat exchanger extends along the outside of the building, even if further construction is needed on the outside of the building, such as backfilling a foundation pit, the cantilever support supports the horizontal connecting pipe from below.

[0006] This technical solution also prevents the horizontal connecting pipes from being bent and damaged by the soil and rock stress of the backfill pit, effectively protecting the horizontal connecting pipes and reducing the risk of gas accumulation after the horizontal connecting pipes are bent upwards and downwards, thus ensuring the stable and efficient operation of the ground source heat exchanger system. This technical solution describes the backfilling method and the equipment used for backfilling; therefore, the backfilling process involves a large amount of work, and removing the filled pipes is difficult. If a pipe ruptures underground, the entire pipe group needs continuous replenishment of circulating fluid or the pipeline needs to be shut down. Excavating to find the leak point involves a large amount of work, is inconvenient, and repairs are difficult once the leak point is located underground. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a geothermal heat exchanger, which solves the problems mentioned in the background section.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a geothermal heat exchanger, comprising a heat exchange tube bent into a "U" shape for heat exchange, the heat exchange tube being divided into an inlet pipe and an outlet pipe, with a cutting-off unit between the inlet and outlet pipe capable of cutting off the circulation of the lower heat exchange tube. The cutting-off unit connects the inlet and outlet pipes, and there are multiple cutting-off units, which are equally spaced between the inlet and outlet pipes. Each cutting-off unit includes a liquid tee on both sides, with the horizontal ends of the two liquid tees fixedly connected by a shell, and the vertical end of the liquid tee connected to the heat exchange tube. Inside the liquid tee, a reversing block is slidably connected to realize the vertical and horizontal conversion of the liquid. The horizontal end of the reversing block is connected to and passes through a connecting pipe, and the outer surfaces of the two connecting pipes are sleeved by the same sleeve. The connecting pipe is slidably connected to the shell, and the sleeve is fixedly connected to the shell.

[0009] Preferably, connecting blocks are fixedly installed on both sides of the outer surface of the sleeve at intervals, the connecting blocks are fixedly connected to the outer shell, a sealing ring is fixedly installed on the outer surface of the connecting tube, the outer surface of the sealing ring is in contact with the outer shell, the sealing ring and the connecting block are fixedly connected by a return spring, and a gas tee is connected and passes through the middle of the outer shell, and adjacent gas tees are connected and pass through each other by a connecting pipe.

[0010] The sealing ring has limit protrusions on both sides, and the outer shell has a limit groove inside that matches the limit protrusions.

[0011] Preferably, the limiting protrusion has a semi-groove on the side near the gas tee, a glass tube is fixedly installed inside the semi-groove, a snap-fit ​​connector is fixedly installed on the side of the glass tube that contacts the outer shell, a spring telescopic sleeve is provided inside the glass tube, the fixed end of the spring telescopic sleeve is fixedly connected to the glass tube, the free end of the spring telescopic sleeve is fixedly connected to the snap-fit ​​connector, and the limiting groove has an insertion hole for accommodating the snap-fit ​​connector.

[0012] Preferably, the surface of the limiting protrusion is provided with an insertion groove, and an insertion block is inserted into the insertion groove. The insertion block is fixedly connected to the spring telescopic sleeve and the glass tube, and the inside of the glass tube is evacuated.

[0013] Preferably, a counterweight is slidably connected inside the connecting pipe, an air supply pipe is fixedly sleeved in the middle of the counterweight, the bottom end of the air supply pipe extends to the bottom of the counterweight, an airbag that unfolds and fits into the connecting pipe is fixedly installed on the outer surface of the counterweight, and an air supply branch pipe is connected to and passes through the top of the airbag.

[0014] Preferably, the pressure used for driving the sealing ring is less than the pressure at which the glass tube breaks, and the pressure at which the glass tube breaks is less than the pressure at which the heat exchange tube is subjected to pressure.

[0015] Preferably, a sealing ring is fixedly installed on the outer surface of the connecting pipes on the side that are close to each other, and the sealing ring is slidably connected inside the sleeve.

[0016] Preferably, the reversing block is cube-shaped, and the diameter of the internal flow channel of the reversing block is the same as the diameter of the liquid tee. Initially, the flow channel of the reversing block is covered by the transverse portion of the liquid tee.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. When a heat exchanger leaks in a heat exchange tube, the heat exchange tube below it is disconnected from the circulation by temporarily connecting the cut-off units one by one, thereby locating the leak point. After finding the leak point, the cut-off unit closest to the leak point is permanently connected, solving the problems of difficulty in finding the leak point and maintenance when the geothermal heat exchanger is damaged in the existing technology.

[0019] 2. In this geothermal heat exchanger, connecting blocks are fixedly installed on both sides of the outer surface of the casing at intervals. The connecting blocks are fixedly connected to the outer shell. A sealing ring is fixedly installed on the outer surface of the connecting pipe. The outer surface of the sealing ring fits against the outer shell. The sealing ring and the connecting block are fixedly connected by a return spring. A gas tee is connected and passes through the middle of the outer shell. Adjacent gas tees are connected and pass through each other by a connecting pipe. Air can be injected into the outer shell through the gas tee to increase the pressure, thereby pushing the sealing ring to move to both sides. This can drive the reversing block to insert into the interior of the liquid tee, thereby achieving the effect of cutting off the heat exchange tube below.

[0020] 3. In this geothermal heat exchanger, a counterweight is slidably connected inside the connecting pipe. An air supply pipe is fixedly sleeved in the middle of the counterweight, and the bottom end of the air supply pipe extends to the bottom of the counterweight. An airbag that unfolds and fits into the connecting pipe is fixedly installed on the outer surface of the counterweight. An air supply branch pipe is connected and passes through the top of the airbag. The counterweight can move the air supply pipe to a specified height and inflate the airbag, so that the airbag fits tightly against the inner wall of the connecting pipe. Then, air is supplied to the connecting pipe and the outer shell located below the counterweight through the air supply pipe. This setting allows for precise height control.

[0021] 4. In this geothermal heat exchanger, a semi-groove is provided on the side of the limiting protrusion near the gas tee. A glass tube is fixedly installed inside the semi-groove, and a clamping connector is fixedly installed on the side of the glass tube in contact with the outer shell. A spring telescopic sleeve is provided inside the glass tube. The fixed end of the spring telescopic sleeve is fixedly connected to the glass tube, and the free end of the spring telescopic sleeve is fixedly connected to the clamping connector. The limiting groove has a plug hole for accommodating the insertion of the clamping connector. With this design, after the reversing block is connected to the liquid tee, the glass tube can be crushed by increasing the pressure, so that the clamping connector can be permanently fixed by inserting it into the plug hole under the action of the spring telescopic sleeve. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the counterweight connection of the present invention;

[0024] Figure 3 This is a half-sectional schematic diagram of the truncated unit of the present invention;

[0025] Figure 4 This is a schematic diagram of the outer casing connection of the present invention;

[0026] Figure 5 This is a schematic diagram of the connecting pipe connection of the present invention;

[0027] Figure 6 This is a schematic diagram of the glass tube connection of the present invention.

[0028] In the diagram: 1. Heat exchange tube; 101. Liquid inlet pipe; 102. Liquid outlet pipe; 2. Cut-off unit; 201. Liquid tee; 202. Reversing block; 203. Connecting pipe; 204. Connecting block; 205. Sleeve; 206. Sealing ring; 207. Return spring; 208. Gas tee; 209. Connecting pipe; 210. Limiting protrusion; 211. Limiting groove; 212. Semi-groove; 213. Glass tube; 214. Snap-fit ​​connector; 215. Spring telescopic sleeve; 216. Insertion hole; 217. Insertion groove; 218. Insertion block; 219. Sealing ring; 220. Outer shell; 3. Counterweight; 4. Gas supply pipe; 5. Airbag; 6. Gas supply branch pipe. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0030] It should be noted that all directional indications in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0031] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

[0033] like Figure 1-6As shown, the geothermal heat exchanger includes a heat exchange tube 1 bent into a "U" shape for heat exchange. The heat exchange tube 1 is divided into an inlet pipe 101 and an outlet pipe 102. A cutting-off unit 2 is provided between the inlet pipe 101 and the outlet pipe 102 to cut off the circulation of the lower heat exchange tube 1. The cutting-off unit 2 connects the inlet pipe 101 and the outlet pipe 102. There are multiple cutting-off units 2, which are equally spaced between the inlet pipe 101 and the outlet pipe 102. The cutting-off unit 2 includes liquid... The liquid tee 201 has two horizontal ends fixedly connected by a housing 220. The vertical end of the liquid tee 201 is connected to the heat exchange tube 1. A reversing block 202, which enables vertical-to-horizontal liquid switching, is slidably connected inside the liquid tee 201. The horizontal end of the reversing block 202 is connected to and passes through a connecting pipe 203. The outer surfaces of the two connecting pipes 203 are sleeved by the same sleeve 205. The connecting pipes 203 are slidably connected to the housing 220, while the sleeve 205 is fixedly connected to the housing 220. By connecting the cut-off units 2 at different heights, it is possible to detect which section of the heat exchange tube 1 is leaking and to cut off the lower section of the heat exchange tube 1.

[0034] Connecting blocks 204 are fixedly installed on both sides of the outer surface of the sleeve 205 at intervals. The connecting blocks 204 are fixedly connected to the outer shell 220. A sealing ring 206 is fixedly installed on the outer surface of the connecting pipe 203. The outer surface of the sealing ring 206 fits against the outer shell 220. The sealing ring 206 and the connecting block 204 are fixedly connected by a return spring 207. A gas tee 208 is connected and passes through the middle of the outer shell 220. Adjacent gas tees 208 are connected and pass through each other by a connecting pipe 209. Air can be injected into the outer shell 220 through the gas tee 208 to increase the pressure, thereby pushing the sealing ring 206 to move to both sides, thereby driving the reversing block 202 to insert into the liquid tee 201, thereby achieving the effect of cutting off the lower heat exchange tube 1.

[0035] The sealing ring 206 has limit protrusions 210 on both sides, and the housing 220 has a limit groove 211 that matches the limit protrusions 210. This arrangement can prevent the sealing ring 206 from rotating.

[0036] A semi-groove 212 is provided on the side of the limiting protrusion 210 near the gas tee 208. A glass tube 213 is fixedly installed inside the semi-groove 212. A snap-fit ​​connector 214 is fixedly installed on the side of the glass tube 213 that contacts the outer shell 220. A spring telescopic sleeve 215 is provided inside the glass tube 213. The fixed end of the spring telescopic sleeve 215 is fixedly connected to the glass tube 213, and the free end of the spring telescopic sleeve 215 is fixedly connected to the snap-fit ​​connector 214. A insertion hole 216 for accommodating the snap-fit ​​connector 214 is provided inside the limiting groove 211. With this arrangement, after the reversing block 202 is connected to the liquid tee 201, the glass tube 213 can be crushed by increasing the pressure. Thus, under the action of the spring telescopic sleeve 215, the snap-fit ​​connector 214 can be inserted into the insertion hole 216 for permanent fixation.

[0037] The surface of the limiting protrusion 210 is provided with a insertion groove 217, and an insertion block 218 is inserted into the insertion groove 217. The insertion block 218 is fixedly connected to the spring telescopic sleeve 215 and the glass tube 213. The inside of the glass tube 213 is evacuated. This setting makes it easy to install the glass tube 213.

[0038] A counterweight 3 is slidably connected inside the connecting pipe 209. An air supply pipe 4 is fixedly sleeved in the middle of the counterweight 3. The bottom end of the air supply pipe 4 extends to the bottom of the counterweight 3. An airbag 5 is fixedly installed on the outer surface of the counterweight 3, which unfolds and fits against the connecting pipe 209. An air supply branch pipe 6 is connected to and passes through the top of the airbag 5. The counterweight 3 can move the air supply pipe 4 to a specified height and inflate the airbag 5, so that the airbag 5 fits tightly against the inner wall of the connecting pipe 209. Then, air is supplied to the connecting pipe 209 and the outer shell 220 located below the counterweight 3 through the air supply pipe 4. This setting allows for precise height control.

[0039] The pressure used to drive the sealing ring 206 is less than the pressure at which the glass tube 213 breaks, and the pressure at which the glass tube 213 breaks is less than the pressure at which the heat exchange tube 1 is subjected to pressure. This arrangement can prevent the heat exchange tube 1 from breaking due to the injection of gas.

[0040] A sealing ring 219 is fixedly installed on the outer surface of the side of the connecting pipe 203 that is close to each other. The sealing ring 219 is slidably connected inside the sleeve 205. This arrangement ensures that the connecting pipe 203 and the sleeve 205 are always in a sealed state.

[0041] The reversing block 202 is a cube. The diameter of the internal flow channel of the reversing block 202 is the same as the diameter of the liquid tee 201. Initially, the flow channel of the reversing block 202 is covered by the lateral part of the liquid tee 201. This setting ensures that the reversing block 202 will not affect the normal flow rate of the liquid tee 201.

[0042] In use, the liquid inside the heat exchange tube 1 is circulated by an external pump. When the heat exchange tube 1 leaks, the counterweight 3 is inserted into the connecting pipe 209 and placed downwards to a specified height. Air is supplied to the airbag 5 so that the airbag 5 is in contact with the connecting pipe 209. The detection is then performed above the bottom cut-off unit 2. Air is supplied to the outer shell 220 through the air supply pipe 4, which pushes the sealing ring 206 to move to both sides. The reversing block 202 is then connected to the inside of the heat exchange tube 1. At this time, the lower heat exchange tube 1 no longer participates in the circulation. The system checks whether the pipe is still leaking. The counterweight 3 is gradually raised until a leak is found. At this time, the pressure of the air supply pipe 4 is increased, causing the glass tube 213 to break due to the pressure difference between the inside and outside. The clamping connector 214 is inserted into the insertion hole 216 under the action of the spring telescopic sleeve 215. At this time, the position of the sealing ring 206 is permanently fixed. The heat exchange tube 1 below it no longer participates in the heat circulation, which solves the problem of difficult maintenance after damage to the geothermal heat exchanger in the prior art.

[0043] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0044] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A geothermal heat exchanger, comprising a heat exchange tube (1) bent into a "U" shape for heat exchange, characterized in that: The heat exchange tube (1) is divided into an inlet pipe (101) and an outlet pipe (102). A cutting-off unit (2) is provided between the inlet pipe (101) and the outlet pipe (102) to cut off the circulation of the heat exchange tube (1) below. The cutting-off unit (2) connects the inlet pipe (101) and the outlet pipe (102). There are multiple cutting-off units (2), and multiple cutting-off units (2) are equally spaced between the inlet pipe (101) and the outlet pipe (102). The cut-off unit (2) includes liquid tees (201) arranged on both sides. The horizontal ends of the two liquid tees (201) are fixedly connected through the outer shell (220). The vertical end of the liquid tees (201) is connected in the heat exchange tube (1). The liquid tees (201) are slidably connected to a reversing block (202) that realizes the vertical and horizontal conversion of the liquid. The horizontal end of the reversing block (202) is connected to and passes through a connecting pipe (203). The outer surfaces of the two connecting pipes (203) are sleeved through the same sleeve (205). The connecting pipe (203) is slidably connected to the outer shell (220), and the sleeve (205) is fixedly connected to the outer shell (220). Connecting blocks (204) are fixedly installed on both sides of the outer surface of the sleeve (205) at intervals. The connecting blocks (204) are fixedly connected to the outer shell (220). A sealing ring (206) is fixedly installed on the outer surface of the connecting pipe (203). The outer surface of the sealing ring (206) is in contact with the outer shell (220). The sealing ring (206) and the connecting block (204) are fixedly connected by a return spring (207). A gas tee (208) is connected and passes through the middle of the outer shell (220). Adjacent gas tees (208) are connected and pass through each other by a connecting pipe (209). The sealing ring (206) is provided with limiting protrusions (210) on both sides, and the outer shell (220) is provided with a limiting groove (211) that matches the limiting protrusions (210). The limiting protrusion (210) has a semi-groove (212) on the side near the gas tee (208). A glass tube (213) is fixedly installed inside the semi-groove (212). A snap-fit ​​connector (214) is fixedly installed on the side of the glass tube (213) that contacts the outer shell (220). A spring telescopic sleeve (215) is provided inside the glass tube (213). The fixed end of the spring telescopic sleeve (215) is fixedly connected to the glass tube (213), and the free end of the spring telescopic sleeve (215) is fixedly connected to the snap-fit ​​connector (214). The limiting slide groove (211) has an insertion hole (216) inside to accommodate the snap-fit ​​connector (214).

2. The geothermal heat exchanger according to claim 1, characterized in that: The surface of the limiting protrusion (210) is provided with a insertion groove (217), and an insertion block (218) is inserted into the insertion groove (217). The insertion block (218) is fixedly connected to the spring telescopic sleeve (215) and the glass tube (213), and the glass tube (213) is evacuated.

3. The geothermal heat exchanger according to claim 2, characterized in that: The internal sliding connection of the connecting pipe (209) is a counterweight (3), and the middle part of the counterweight (3) is fixedly sleeved with an air supply pipe (4). The bottom end of the air supply pipe (4) extends to the bottom of the counterweight (3). An air bag (5) that unfolds and fits with the connecting pipe (209) is fixedly installed on the outer surface of the counterweight (3). An air supply branch pipe (6) is connected and passes through the upper part of the air bag (5).

4. The geothermal heat exchanger according to claim 3, characterized in that: The pressure used to drive the sealing ring (206) is less than the pressure at which the glass tube (213) breaks, and the pressure at which the glass tube (213) breaks is less than the pressure at which the heat exchange tube (1) is subjected to pressure.

5. The geothermal heat exchanger according to claim 4, characterized in that: A sealing ring (219) is fixedly installed on the outer surface of the connecting pipes (203) on the side that are close to each other, and the sealing ring (219) is slidably connected inside the sleeve (205).

6. The geothermal heat exchanger according to claim 5, characterized in that: The reversing block (202) is a cube. The diameter of the internal flow channel of the reversing block (202) is the same as the diameter of the liquid tee (201). Initially, the flow channel of the reversing block (202) is covered by the transverse part of the liquid tee (201).

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