Geothermal source heat energy exchanger

Abstract

The invention provides a geothermal source heat energy exchanger and relates to the field of geothermal source use. The geothermal source heat energy exchanger comprises a heat exchange pipe which is used for heat exchange and bent into a U shape, the heat exchange pipe is divided into a liquid inlet pipe and a liquid outlet pipe, a plurality of cut-off units capable of cutting off circulation of the heat exchange pipe below are arranged between the liquid inlet pipe and the liquid outlet pipe, the cut-off units are communicated with the liquid inlet pipe and the liquid outlet pipe, and the number of the cut-off units is larger than that of the cut-off units. The multiple cut-off units are arranged between the liquid inlet pipe and the liquid outlet pipe at equal intervals. According to the geothermal source heat energy exchanger, when the heat exchange pipes leak, the cut-off units are temporarily connected one by one, so that the heat exchange pipes below the cut-off units are not connected into circulation, the leakage points of the heat exchange pipes can be found, and after the leakage points are found, the cut-off units closest to the leakage points above the leakage points are permanently connected; the problems that leakage points are not easy to find and maintenance is difficult when the geothermal heat exchanger is damaged in the prior art are solved.

Description

Technical Field

[0001] The invention relates to the field of geothermal source use, in particular to a geothermal source heat energy exchanger. Background Art

[0002] Geothermal heat pump system, also known as ground source heat pump, uses ground source energy (soil, groundwater, surface water, low-temperature geothermal water and tail water) as the cooling source for heat pump cooling in summer and the low-temperature heat source for heating in winter. It is also a system for heating, cooling and domestic hot water. It is used to replace the traditional mode of using refrigerators and boilers for air conditioning, heating and heating. It is an effective way to improve the urban atmospheric environment and save energy, and it is also a new development direction for the utilization of ground source energy in China.

[0003] (CN209371569U) A geothermal heat pump well and a geothermal heat pump system, the geothermal heat pump well comprises a well pit and a heat exchange pipe; the depth of the well pit is 600 to 4000 m; the heat exchange pipe comprises an inlet pipe, a return pipe, a constant pressure water injection device and a well body; the well body is arranged in 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 arranged between the well pit and the well body; the constant pressure water injection device is arranged between the well pit and the well body, and water is injected between the well pit and the well body to improve the thermal conductivity of the filling medium.

[0004] The ground source heat pump well and ground source heat pump system of this technical solution can exchange deep and medium geothermal energy, and the available heat reaches 150-200W / m, with high heat utilization rate and stable heat source, thus reducing the number of wells to be drilled. This technical solution points out that the pipe is placed inside the well pit and filled with filling medium.

[0005] The existing patent (CN112524827A) discloses a ground source heat exchanger installation structure and a ground source heat exchanger installation method. The ground source heat exchanger installation structure includes a buried pipe heat exchanger, a horizontal connecting pipe and a cantilever beam support. The buried pipe heat exchanger is arranged 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 beam support is installed on the outside of the building in the horizontal direction. When the horizontal connecting pipe connected to the buried pipe heat exchanger is extended along the outside of the building, even if the outside of the building needs to continue construction, such as backfilling of the foundation pit, the cantilever beam support is supported on the lower side of the horizontal connecting pipe.

[0006] The horizontal connecting pipe of this technical solution is not easily bent and damaged by the soil and rock stress of the foundation pit backfill, which effectively protects the horizontal connecting pipe and reduces the risk of gas collection after the horizontal connecting pipe is bent up and down, ensuring the stable and efficient operation of the ground source heat exchanger system. This technical solution discusses the backfilling method and the equipment used for backfilling. Therefore, the backfilling process is relatively large in engineering, and it is difficult to remove the filled pipes again. When the pipes break underground, the group of pipes needs to continuously replenish the circulating fluid or suspend the pipeline. The excavation method is relatively large in engineering to find the leak point, which is inconvenient and difficult to repair after finding the leak point. Summary of the invention

[0007] In view of the deficiencies of the prior art, the present invention provides a geothermal heat exchanger to solve the problems raised in the above background technology.

[0008] To achieve the above purpose, the present invention is implemented through the following technical scheme: a geothermal source heat energy exchanger, comprising a heat exchange tube for heat exchange and bent into a "U" shape, the heat exchange tube is divided into a liquid inlet tube and a liquid outlet tube, a cut-off unit that can cut off the circulation of the lower heat exchange tube is arranged between the liquid inlet tube and the liquid outlet tube, the cut-off unit connects the liquid inlet tube and the liquid outlet tube, the number of the cut-off units is multiple, and the multiple cut-off units are arranged at equal intervals between the liquid inlet tube and the liquid outlet tube, the cut-off unit comprises a liquid tee arranged on both sides, the horizontal ends of the two liquid tees are fixedly connected by an outer shell, the vertical end of the liquid tee is connected to the heat exchange tube, the internal sliding connection of the liquid tee is provided with a reversing block for realizing vertical and horizontal conversion of the liquid, the horizontal end of the reversing block is connected and penetrated with a connecting pipe, the outer surfaces of the two connecting pipes are sleeved by the same sleeve, the connecting pipe is slidably connected to the outer shell, and the sleeve is fixedly connected to the outer shell.

[0009] Preferably, connection blocks distributed at intervals are fixedly installed on both sides of the outer surface of the sleeve, the connection 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 with the outer shell, the sealing ring and the connection block are fixedly connected by a reset spring, a gas tee is connected and penetrated in the middle of the outer shell, and adjacent gas tees are connected and penetrated by a connecting pipe.

[0010] Limiting protrusions are arranged on both sides of the sealing ring, and limiting sliding grooves matching with the limiting protrusions are arranged inside the shell.

[0011] Preferably, a semi-groove is provided on the side of the limiting protrusion close to the gas tee, a glass tube is fixedly installed inside the semi-groove, a card joint is fixedly installed on the contact side of the glass tube and 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 card joint, and a plug hole for accommodating the insertion of the card joint is provided inside the limiting slide groove.

[0012] Preferably, a plug-in groove is provided on the surface of the limiting protrusion, a plug-in block is plugged into the plug-in groove, the plug-in block is fixedly connected to the spring telescopic sleeve and the glass tube, and the interior of the glass tube is evacuated.

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

[0014] Preferably, the pressure used to drive the sealing ring is less than the breaking pressure of the glass tube, and the breaking pressure of the glass tube is less than the bearing pressure of the heat exchange tube.

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

[0016] Preferably, the reversing block is in the shape of a regular cube, the diameter of the flow channel inside the reversing block is the same as the diameter of the liquid tee, and initially, the flow channel of the reversing block is covered by the lateral portion of the liquid tee.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1. When a leak occurs in a heat exchange tube of the geothermal heat exchanger, the cut-off units are temporarily connected one by one so that the heat exchange tube below is not connected to the circulation, thereby finding the leak point of the heat exchange tube. After the leak point is found, the cut-off unit above the leak point and closest to the leak point is permanently connected, thereby solving the problem in the prior art that it is difficult to find the leak point and repair the geothermal heat exchanger when it is damaged.

[0018] 2. The geothermal heat source heat energy exchanger has connection blocks fixedly installed on both sides of the outer surface of the casing at intervals, the connection 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 is fitted with the outer shell, the sealing ring and the connection block are fixedly connected by a reset spring, a gas tee is connected and penetrated in the middle of the outer shell, adjacent gas tees are connected and penetrated by a connecting pipe, and 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, thereby driving the reversing block to be inserted into the interior of the liquid tee, and then achieving the effect of cutting off the heat exchange tube below.

[0019] 3. In the geothermal heat source heat energy exchanger, a counterweight is slidably connected to the inside of the connecting pipe, an air supply pipe is fixedly sleeved on the middle part of the counterweight, the bottom end of the air supply pipe extends to the bottom of the counterweight, and an air bag that is unfolded and fits with the connecting pipe is fixedly installed on the outer surface of the counterweight. An air supply branch pipe is connected to and passes through the top of the air bag. The counterweight can drive the air supply pipe to move to a specified height and inflate the air bag so that the air bag fits tightly against the inner wall of the connecting pipe, and then the connecting pipe and the outer shell below the counterweight are supplied with air through the air supply pipe. Such an arrangement can accurately control the height.

[0020] 4. The heat exchanger of the geothermal source is provided with a semi-groove on one side of the limiting protrusion close to the gas tee, a glass tube is fixedly installed inside the semi-groove, a card joint is fixedly installed on the contact side of the glass tube with the 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 card joint, and a plug hole for accommodating the insertion of the card joint is provided inside the limiting slide groove. Through such an arrangement, after the reversing block is connected to the liquid tee, the glass tube can be squeezed and broken by increasing the pressure, so that the card joint can be inserted into the plug hole under the action of the spring telescopic sleeve to achieve permanent fixation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the connection of the counterweight block of the present invention; Figure 3 A half-section schematic diagram of a truncation unit of the present invention; Figure 4 This is a schematic diagram of the shell connection of the present invention; Figure 5 This is a schematic diagram of the connection of the connecting pipe of the present invention; Figure 6 This is a schematic diagram of the glass tube connection of the present invention.

[0022] In the figure: 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 slide groove; 212. semi-groove; 213. glass tube; 214. clamping joint; 215. spring telescopic sleeve; 216. plug-in hole; 217. plug-in groove; 218. plug-in block; 219. sealing ring; 220. shell; 3. counterweight; 4. air supply pipe; 5. air bag; 6. air supply branch pipe. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0024] It should be noted that all directional indications in the embodiments of the present application are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0025] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0026] In addition, in this application, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0027] like Figure 1-6As shown, the geothermal heat exchanger includes a heat exchange tube 1 for heat exchange and bent into a "U" shape. The heat exchange tube 1 is divided into a liquid inlet tube 101 and a liquid outlet tube 102. A cut-off unit 2 that can cut off the circulation of the lower heat exchange tube 1 is arranged between the liquid inlet tube 101 and the liquid outlet tube 102. The cut-off unit 2 connects the liquid inlet tube 101 and the liquid outlet tube 102. There are multiple cut-off units 2. The multiple cut-off units 2 are evenly spaced between the liquid inlet tube 101 and the liquid outlet tube 102. The cut-off unit 2 includes liquid The liquid tee 201 has a body, and the horizontal ends of the two liquid tees 201 are fixedly connected through the shell 220. The vertical end of the liquid tee 201 is connected to the heat exchange tube 1. The liquid tee 201 is internally slidably connected with a reversing block 202 for realizing the vertical and horizontal conversion of the liquid. The horizontal end of the reversing block 202 is connected and penetrated with a connecting pipe 203. The outer surfaces of the two connecting pipes 203 are sleeved by the same sleeve 205. The connecting pipe 203 is slidably connected to the shell 220, and the sleeve 205 is fixedly connected to the shell 220. By connecting the cut-off units 2 at different heights, it is possible to detect which specific section of the heat exchange tube 1 is leaking, and the heat exchange tube 1 below can be cut off.

[0028] Connecting blocks 204 are fixedly installed at intervals on both sides of the outer surface of the sleeve 205, and 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, and 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 via a return spring 207. A gas tee 208 is connected and penetrated in the middle of the outer shell 220, and adjacent gas tees 208 are connected and penetrated by a connecting pipe 209. The gas tee 208 can increase the pressure by injecting air into the outer shell 220, thereby pushing the sealing ring 206 to move to both sides, thereby driving the reversing block 202 to be inserted into the interior of the liquid tee 201, thereby achieving the effect of cutting off the heat exchange tube 1 below.

[0029] Limiting protrusions 210 are arranged on both sides of the sealing ring 206 , and limiting sliding grooves 211 adapted to the limiting protrusions 210 are opened inside the housing 220 . Such an arrangement can prevent the sealing ring 206 from rotating.

[0030] A semi-groove 212 is provided on one side of the limiting protrusion 210 close to the gas tee 208, a glass tube 213 is fixedly installed inside the semi-groove 212, a clamping joint 214 is fixedly installed on the side of the glass tube 213 in contact with the shell 220, a spring telescopic sleeve 215 is provided inside the glass tube 213, a fixed end of the spring telescopic sleeve 215 is fixedly connected to the glass tube 213, a free end of the spring telescopic sleeve 215 is fixedly connected to the clamping joint 214, a plug-in hole 216 for accommodating the insertion of the clamping joint 214 is provided inside the limiting slide groove 211, through such a setting, after the reversing block 202 is connected to the liquid tee 201, the glass tube 213 can be squeezed and broken by increasing the pressure, so that under the action of the spring telescopic sleeve 215, the clamping joint 214 can be inserted into the plug-in hole 216 to achieve permanent fixation.

[0031] An insertion groove 217 is provided on the surface of the limiting protrusion 210, 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 interior of the glass tube 213 is evacuated. Such an arrangement facilitates the installation of the glass tube 213.

[0032] The connecting tube 209 is slidably connected to the inside of the connecting tube 209, and an air supply pipe 4 is fixedly sleeved in the middle of the counterweight block 3. The bottom end of the air supply pipe 4 extends to the bottom of the counterweight block 3. An air bag 5 that is unfolded and fits with the connecting tube 209 is fixedly installed on the outer surface of the counterweight block 3. An air supply branch pipe 6 is connected to and passes through the top of the air bag 5. The counterweight block 3 can drive the air supply pipe 4 to move to a specified height and inflate the air bag 5 so that the air bag 5 fits tightly against the inner wall of the connecting tube 209. Then, the connecting tube 209 and the outer shell 220 located below the counterweight block 3 are supplied with air through the air supply pipe 4. Such an arrangement can accurately control the height.

[0033] The pressure used to drive the sealing ring 206 is lower than the rupture pressure of the glass tube 213 , and the rupture pressure of the glass tube 213 is lower than the bearing pressure of the heat exchange tube 1 . This arrangement can prevent the heat exchange tube 1 from rupturing due to the injected gas.

[0034] A sealing ring 219 is fixedly installed on the outer surface of the connecting pipe 203 on one side close to each other, and the sealing ring 219 is slidably connected to the inside of the sleeve 205. This arrangement can ensure that the connecting pipe 203 and the sleeve 205 are always in a sealed state.

[0035] The reversing block 202 is in the shape of a regular cube, and 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. Such a setting can ensure that the reversing block 202 will not affect the normal flow rate of the liquid tee 201.

[0036] During use, the liquid in the heat exchange tube 1 is circulated by an external pump. When the heat exchange tube 1 leaks, the counterweight 3 is inserted from the connecting tube 209 and placed downward to a specified height, and air is supplied to the airbag 5 so that the airbag 5 fits with the connecting tube 209, so that the detection is carried out above the bottom cut-off unit 2, and air is supplied to the shell 220 through the air supply pipe 4, which can push the sealing ring 206 to move to both sides, and connect the reversing block 202 to the inside of the heat exchange tube 1. At this time, the heat exchange tube 1 below no longer participates in the circulation, and the pipeline is checked for leakage. The counterweight 3 is gradually lifted upward until no leakage is found. At this time, the pressure of the air supply pipe 4 is increased, so that the glass tube 213 is broken due to the pressure difference between the inside and the outside. The clamping joint 214 is inserted into the inside of the plug hole 216 under the action of the spring telescopic sleeve 215, and the position of the sealing ring 206 is permanently fixed. The heat exchange tube 1 below it no longer participates in the heat cycle, which solves the problem of difficult maintenance after the geothermal heat exchanger is damaged in the prior art.

[0037] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0038] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0039] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A geothermal heat exchanger, comprising a heat exchange tube (1) for heat exchange and bent into a "U" shape, characterized in that: The heat exchange tube (1) is divided into a liquid inlet tube (101) and a liquid outlet tube (102); a cut-off unit (2) capable of cutting off the circulation of the lower heat exchange tube (1) is arranged between the liquid inlet tube (101) and the liquid outlet tube (102); the cut-off unit (2) is connected to the liquid inlet tube (101) and the liquid outlet tube (102); there are a plurality of cut-off units (2); and the plurality of cut-off units (2) are arranged at equal intervals between the liquid inlet tube (101) and the liquid outlet tube (102); The cut-off unit (2) comprises a liquid tee (201) arranged on both sides, the horizontal ends of the two liquid tees (201) being fixedly connected via a shell (220), the vertical ends of the liquid tees (201) being connected to the heat exchange tube (1), the interior of the liquid tee (201) being slidably connected to a reversing block (202) for realizing vertical and horizontal conversion of liquid, the horizontal end of the reversing block (202) being connected to and penetrating a connecting pipe (203), the outer surfaces of the two connecting pipes (203) being sleeved by a same sleeve (205), the connecting pipe (203) being slidably connected to the shell (220), and the sleeve (205) being fixedly connected to the shell (220).

2. The geothermal heat exchanger according to claim 1, characterized in that: Connecting blocks (204) are fixedly mounted at intervals on both sides of the outer surface of the sleeve (205); the connecting blocks (204) are fixedly connected to the outer shell (220); a sealing ring (206) is fixedly mounted 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 via a return spring (207); a gas tee (208) is connected to and penetrates the middle of the outer shell (220); adjacent gas tees (208) are connected and penetrated via a connecting pipe (209).

3. The geothermal heat exchanger according to claim 2, characterized in that: Limiting protrusions (210) are provided on both sides of the sealing ring (206), and limiting sliding grooves (211) adapted to the limiting protrusions (210) are provided inside the housing (220).

4. The geothermal heat exchanger according to claim 3, characterized in that: A semi-groove (212) is provided on a side of the limiting protrusion (210) close to the gas tee (208); a glass tube (213) is fixedly installed inside the semi-groove (212); a clamping joint (214) is fixedly installed on the contact side of the glass tube (213) with the housing (220); a spring telescopic sleeve (215) is provided inside the glass tube (213); a fixed end of the spring telescopic sleeve (215) is fixedly connected to the glass tube (213); a free end of the spring telescopic sleeve (215) is fixedly connected to the clamping joint (214); and a plug-in hole (216) for accommodating the insertion of the clamping joint (214) is provided inside the limiting sliding groove (211).

5. The geothermal heat exchanger according to claim 4, characterized in that: The surface of the limiting protrusion (210) is provided with an inserting groove (217), the interior of the inserting groove (217) is inserted with an inserting block (218), the inserting block (218) is fixedly connected to the spring telescopic sleeve (215) and the glass tube (213), and the interior of the glass tube (213) is evacuated.

6. The geothermal heat exchanger according to claim 5, characterized in that: The connecting tube (209) is slidably connected to a counterweight (3) inside, 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 air bag (5) is fixedly mounted on the outer surface of the counterweight (3) and is unfolded to fit the connecting tube (209), and an air supply branch pipe (6) is connected to and passes through the top of the air bag (5).

7. The geothermal heat exchanger according to claim 6, characterized in that: The pressure used to drive the sealing ring (206) is less than the rupture pressure of the glass tube (213), and the rupture pressure of the glass tube (213) is less than the bearing pressure of the heat exchange tube (1).

8. The geothermal heat exchanger according to claim 1, characterized in that: A sealing ring (219) is fixedly mounted on the outer surface of one side of the connecting pipe (203) that is close to each other, and the sealing ring (219) is slidably connected to the inside of the sleeve (205).

9. The geothermal heat exchanger according to claim 1, characterized in that: The reversing block (202) is in the shape of a regular cube, and the diameter of the flow channel inside 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 portion of the liquid tee (201).

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