Rock-soil energy storage circulating heat exchange system

Abstract

The utility model discloses a rock-soil energy storage circulation heat exchange system, which relates to the technical field of heat exchange systems, and comprises an outer pipe buried underground, well cementation filler is filled between the outer pipe and surrounding soil, an inner pipe is sleeved in the outer pipe, the outer wall of the inner pipe is connected with a temperature measurement cable through a fixing assembly, and the temperature measurement cable is connected with a temperature sensor. A temperature measuring device is installed on the temperature measuring cable, one end of the top of the temperature measuring cable penetrates through the outer pipe, the temperature measuring cable is installed on the outer pipe through a cable gland, and the bottom of the inner pipe is connected with a balance weight pipe. According to the rock-soil energy storage circulation heat exchange system, the occupied area of the ground surface can be saved, the situation that a wellhead device is collided can be avoided, meanwhile, the influence of the surrounding temperature on a heat exchange medium in the water outlet pipe can be reduced, the heat preservation capacity of the water outlet pipe is improved through the backfill soil covering the surrounding, and therefore the heat loss of the heat exchange medium is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of heat exchange systems, and more specifically to a geotechnical energy storage cyclic heat exchange system. Background Art

[0002] A heat exchange geothermal well is a system that utilizes underground thermal energy for heat exchange, mainly used for the development and utilization of geothermal energy, especially in the fields of heating, hot water supply, and power generation. The design of such geothermal wells aims to efficiently and sustainably extract heat from underground reservoirs while reducing environmental impact.

[0003] The top of the existing heat exchange well extends out of the ground surface, which facilitates the extraction of the heat-exchanged geothermal water. For example, the Chinese patent with the application number 202322941765.2 discloses a wellhead device for a medium-deep geothermal buried pipe heat exchange well. The temperature measurement optical cable penetration mechanism includes a ferrule joint body, a ferrule assembly, and a compression nut. For this wellhead device for a medium-deep geothermal buried pipe heat exchange well, the top of the heat exchange well extends out of the ground surface to facilitate the installation of the inner pipe and the detection cable. However, the following problems still exist during use:

[0004] 1. Since the top of the heat exchange well extends out of the ground surface, the extended part is not only easily affected by cold weather, etc., resulting in bumps, but also has an impact on the surrounding building environment during installation. Not only an installation position needs to be reserved, but also space needs to be reserved for the erection of pipelines.

[0005] 2. When the water outlet end at the top of the geothermal well is buried underground, the connection position between the inner pipe and the outer pipe of the heat exchange well is relatively fragile and is easily damaged due to the pressure at the top and bottom, resulting in water leakage at the connection.

[0006] Therefore, it is very necessary to propose a geotechnical energy storage cyclic heat exchange system to solve the above problems. Summary of the Utility Model

[0007] In view of the above problems, the utility model provides a geotechnical energy storage cyclic heat exchange system; it has the function of reducing the ground occupation area, improving the heat preservation ability of the water outlet pipe, increasing the pressure-bearing capacity of the top of the inner pipe, and extending the service life of the geothermal well.

[0008] The utility model specifically adopts the following technical solutions to achieve the above objectives:

[0009] Geotechnical energy storage cyclic heat exchange system, including an outer pipe buried underground. There is well-fixing filler filled between the outer pipe and the surrounding soil. An inner pipe is sleeved inside the outer pipe. A temperature measuring cable is connected to the outer wall of the inner pipe through a fixing component. A temperature measuring device is installed on the temperature measuring cable. One end of the top of the temperature measuring cable passes through the outer pipe, and the temperature measuring cable is installed on the outer pipe through a gland. A counterweight pipe is connected to the bottom of the inner pipe;

[0010] The top of the outer wall of the outer pipe is connected with a water inlet pipe. The top of the inner pipe is provided with a water outlet pipe, and the inner pipe and the water outlet pipe are connected through a bent pipe. The top of the outer pipe is covered with backfill soil. The temperature measuring cable, the water inlet pipe and the water outlet pipe are located in the backfill soil.

[0011] Preferably, a support ring is connected to the top of the outer pipe through bolts. A baffle is sleeved between the top of the outer pipe and the support ring. The baffle is connected between the inner pipe and the bent pipe. The top of the support ring is connected with a top cover through bolts. A mating joint part is arranged on one side of the support ring and the top cover. The water outlet pipe passes through the symmetric joint parts.

[0012] Preferably, a half-piece sleeve is sleeved on the side of the symmetric joint part close to the water outlet pipe. One end of the half-piece sleeve is provided with a flange. A sealing gasket is arranged on one side of the flange. External threads are arranged on the outer ring surface of the half-piece sleeve far from the flange. The external threads on the symmetric half-piece sleeves cooperate with each other to form a complete external thread. Symmetric grooves are arranged on the side of the half-piece sleeve facing the water outlet pipe, and a sealing rubber strip is connected in the grooves.

[0013] Preferably, a connecting cover is threadedly connected to the side of the half-piece sleeve far from the flange. The connecting cover is sleeved outside the water outlet pipe. An extrusion part is arranged on the side of the connecting cover close to the joint part. An annular groove is arranged on one side of the extrusion part, and a first annular sealing ring is connected in the annular groove. An extrusion ring is arranged on the side of the joint part close to the connecting cover, and the extrusion ring can exert an extrusion effect on the first annular sealing ring.

[0014] Preferably, a second annular sealing ring is connected to the inner side of the connecting cover, and the second annular sealing ring is in contact with the side of the half-piece sleeve close to the external thread.

[0015] Preferably, symmetric reinforcing ribs are connected to the inner ring surfaces of the support ring and the top cover.

[0016] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0017] 1. By burying the wellhead devices of the outer and inner pipes of the heat exchange well underground, this device can not only save the occupied area on the ground surface, but also avoid the situation of the wellhead device being collided. At the same time, it can reduce the influence of the surrounding temperature on the heat exchange medium in the outlet pipe, and increase the heat preservation ability of the outlet pipe through the backfill soil covering the surrounding, so as to reduce the heat loss of the heat exchange medium.

[0018] 2. By setting a support ring and a top cover on the top of the outer pipe, this device can increase the pressure-bearing capacity at the top of the inner pipe, avoid the situation that the pressure at the top of the wellhead position of the outer pipe is too large, resulting in damage at the connection between the inner pipe and the outer pipe, and has the effect of enhancing the durability of the geothermal well.

[0019] 3. By setting a first annular sealing ring and a second annular sealing ring at both ends of the thread, this device can increase the sealing performance at both ends of the thread, avoid rainwater seepage causing the thread to rust, and thus the situation that it is not easy to disassemble the connection cover, which provides convenience for the subsequent maintenance of the geothermal well. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram when the utility model is buried underground;

[0021] Figure 2 It is a schematic diagram of the structure of the outer pipe and the support ring in the utility model;

[0022] Figure 3 It is a cross-sectional view of the structure of the outer pipe and the support ring in the utility model;

[0023] Figure 4 It is a schematic diagram of the structure of the outlet pipe and the support ring in the utility model;

[0024] Figure 5 It is a cross-sectional view of the structure of the half sleeve and the connection cover in the utility model.

[0025] Reference Signs:

[0026] 101. Outer pipe; 102. Inner pipe; 103. Temperature measurement cable; 104. Counterweight pipe; 105. Inlet pipe; 106. Outlet pipe; 107. Elbow; 108. Backfill soil; 109. Support ring; 110. Baffle; 111. Top cover; 112. Joint part; 113. Half sleeve; 114. Flange; 115. Sealing gasket; 116. Sealing rubber strip; 117. Connection cover; 118. Extrusion part; 119. First annular sealing ring; 120. Extrusion ring; 121. Second annular sealing ring; 122. Reinforcing rib. DETAILED DESCRIPTION OF THE INVENTION

[0027] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0028] Please refer to Figures 1-5 , a geotechnical energy storage cyclic heat exchange system, which includes an outer pipe 101 buried underground. There is well cementing filler filled between the outer pipe 101 and the surrounding soil. The well cementing filler is composed of drilling original slurry and fine sand. The outer pipe 101 is made of galvanized steel pipe, and the pipe fittings are connected by screw threads. Liquid thread seal tape is applied at the screw threads and wrapped with hemp for sealing; the bottom of the casing is sealed with a plug to isolate the mud; during the process of lowering the pipe, clear water is poured into the pipe. After the outer pipe 101 is installed, it is backfilled and sealed with grouting material within 12 hours. When grouting, it is evenly backfilled around the wellhead to ensure density and no cavity; the backfill material is backfilled with original soil and fine sand. The backfill process should be kept uniform to ensure uniform and dense backfill. When necessary, the vibration method or water sinking method is used. An inner pipe 102 is sleeved inside the outer pipe 101. The inner pipe 102 is made of a φ40*3.7mm PE pipe, and the outer pipe 101 is made of a φ89*4mm galvanized steel pipe. A temperature measurement cable 103 is connected to the outer wall of the inner pipe 102 through a fixing component. The fixing component is preferably waterproof tape for fixing the temperature measurement cable 103. A temperature measurement device is installed on the temperature measurement cable 103. One end of the top of the temperature measurement cable 103 passes through the outer pipe 101, and the temperature measurement cable 103 is installed on the outer pipe 101 through a gland. The bottom of the inner pipe 102 is connected with a counterweight pipe 104. Preferably, the inner pipe 102 is connected with the counterweight pipe 104 through galvanized iron wire. The counterweight pipe 104 uses solid round steel with a diameter of 30 - 40mm as the counterweight, the length is not more than 2m, and the weight is not less than 10kg; the counterweight round steel is connected with the inner pipe 102 by steel wire. Finally, when lowering the pipe, the counterweight round steel needs to be lowered to the bottom of the hole without being suspended.

[0029] Refer to Figure 1 , the top of the outer wall of the outer pipe 101 is connected with a water inlet pipe 105, and the top of the inner pipe 102 is provided with a water outlet pipe 106. Preferably, the water inlet pipe 105 and the water outlet pipe 106 are arranged in parallel. The inner pipe 102 and the water outlet pipe 106 are connected through an elbow 107. The top of the outer pipe 101 is covered with backfill soil 108. The top of the geothermal well is buried underground through the backfill soil 108, thereby saving the occupied area on the ground and reducing the situation of the geothermal well being collided. The temperature measurement cable 103, the water inlet pipe 105 and the water outlet pipe 106 are located in the backfill soil 108. One end of the temperature measurement cable extending out of the outer pipe 101 is located at the bottom of the water inlet pipe 105.

[0030] The following provides a structure for supporting and protecting the top of a geothermal well to reduce the pressure on the top of the inner pipe 102: Refer to Figure 2 and Figure 3 , specifically, a support ring 109 is connected to the top of the outer pipe 101 by bolts. A baffle 110 is sleeved between the top of the outer pipe 101 and the support ring 109. The baffle 110 is located between the support ring 109 and the outer pipe 101 to prevent the baffle 110 from coming into contact with the outside soil and reduce the situation of water leakage caused by corrosion and rust. The baffle 110 is connected between the inner pipe 102 and the elbow pipe 107. The top of the support ring 109 is connected to a top cover 111 by bolts. The support ring 109 and the top cover 111 are used to protect the elbow pipe 107 and the baffle 110. The internal reinforcing ribs 122 are used to enhance the pressure-bearing capacity of the top. A mating joint part 112 is provided on one side of the support ring 109 and the top cover 111. The water outlet pipe 106 passes through the symmetric joint parts 112.

[0031] When the water outlet pipe 106 is installed between the support ring 109 and the top cover 111, there will be gaps for infiltration, resulting in the rusting of the baffle 110. The following provides a structure to avoid water leakage through the gaps: Refer to Figure 4 and Figure 5 , specifically, a half-piece sleeve 113 is sleeved on the side of the symmetric joint part 112 close to the water outlet pipe 106. The symmetric half-piece sleeves 113 can be spliced together to sleeve on the water outlet pipe 106. A retaining edge 114 is provided at one end of the half-piece sleeve 113. A sealing gasket 115 is provided on one side of the retaining edge 114. Through the deformation and compression of the sealing gasket 115, it is convenient for the two half-piece sleeves 113 to be spliced together well, and at the same time, the sealing performance at the connection with the water outlet pipe 106 can be improved. External threads are provided on the outer circumferential surface of the half-piece sleeve 113 away from the retaining edge 114. The external threads on the symmetric half-piece sleeves 113 cooperate with each other to form a complete external thread. Symmetric grooves are provided on the side of the half-piece sleeve 113 facing the water outlet pipe 106. A sealing rubber strip 116 is connected in the grooves. The half-piece sleeve 113 presses on the water outlet pipe 106 through the sealing rubber strip 116 on the inner circumferential surface to increase the sealing performance at the connection.

[0032] Specifically, refer to Figure 4 and Figure 5, on the side of the half casing 113 away from the edge 114, a connection cover 117 is threadedly connected. Through the connection cover 117, two half casings 113 can be installed together. The connection cover 117 is sleeved outside the water outlet pipe 106. On the side of the connection cover 117 close to the connection part 112, an extrusion part 118 is provided. On one side of the extrusion part 118, an annular groove is opened, and a first annular sealing ring 119 is connected in the annular groove. After the connection cover 117 is installed on the symmetric half casings 113, the first annular sealing ring 119 and the second annular sealing ring 121 can seal both sides of the thread, which can protect the thread inside the connection cover 117 and prevent liquid from seeping into the gap and affecting the thread. On the side of the connection part 112 close to the connection cover 117, an extrusion ring 120 is provided. After the connection cover 117 is installed on the half casing 113, the extrusion part 118 will move towards the extrusion ring 120 and come into contact, and the first annular sealing ring 119 will deform to increase the sealing performance of the connection part. The extrusion ring 120 can exert an extrusion effect on the first annular sealing ring 119.

[0033] Specifically, referring to Figure 4 and Figure 5 , a second annular sealing ring 121 is connected to the inner side of the connection cover 117. The first annular sealing ring 119 and the second annular sealing ring 121 can seal both ends of the thread and play a role in protecting the thread. The second annular sealing ring 121 is in contact with the side of the half casing 113 close to the external thread.

[0034] Specifically, referring to Figure 3 and Figure 4 , symmetric reinforcing ribs 122 are connected to the inner ring surfaces of the support ring 109 and the top cover 111. The reinforcing ribs 122 are used to increase the bearing capacity of the support ring 109 and the top cover 111 for the top.

[0035] In this embodiment, in the first step, first lower the outer pipe 101 into the opened cavity, fill the well cementing filler between the outer pipe 101 and the surrounding soil, then lower the inner pipe 102 installed with the temperature measuring cable 103 into the outer pipe 101, and then fix the baffle 110 between the outer pipe 101 and the support ring 109 through bolts;

[0036] In the second step, connect the water outlet pipe 106 to the inner pipe 102 through the elbow 107, then sleeve the symmetric half casings 113 on the water outlet pipe 106, and then install the top cover 111 on the support ring 109 through bolts. It should be noted that the edge 114 at one end of the half casing 113 should be located inside the connection part 112. Finally, after threadedly installing the connection cover 117 on the half casing 113, the installation is completed.

[0037] The above embodiments are only the preferred embodiments of the present utility model, and cannot be used to limit the scope of protection of the present utility model. Any non-substantial changes and substitutions made by those skilled in the art based on the present utility model fall within the scope of protection required by the present utility model.

Claims

1. Geotechnical energy storage cyclic heat exchange system, including an outer pipe (101) buried underground, with well-filling material filled between the outer pipe (101) and the surrounding soil, and an inner pipe (102) sleeved inside the outer pipe (101), characterized in that: A temperature measuring cable (103) is connected to the outer wall of the inner pipe (102) through a fixing component. A temperature measuring device is installed on the temperature measuring cable (103). One end at the top of the temperature measuring cable (103) passes through the outer pipe (101). The temperature measuring cable (103) is installed on the outer pipe (101) through a gland. A counterweight pipe (104) is connected to the bottom of the inner pipe (102). A water inlet pipe (105) is connected to the top of the outer wall of the outer pipe (101). An outlet pipe (106) is provided at the top of the inner pipe (102). The inner pipe (102) and the outlet pipe (106) are connected by a bent pipe (107). The top of the outer pipe (101) is covered with backfill soil (108). The temperature measuring cable (103), the water inlet pipe (105) and the outlet pipe (106) are located in the backfill soil (108).

2. The geotechnical energy storage cyclic heat exchange system according to claim 1, characterized in that: A support ring (109) is connected to the top of the outer pipe (101) by bolts. A baffle (110) is sleeved between the top of the outer pipe (101) and the support ring (109). The baffle (110) is connected between the inner pipe (102) and the bent pipe (107). A top cover (111) is connected to the top of the support ring (109) by bolts. A mating joint (112) is provided on one side of the support ring (109) and the top cover (111). The outlet pipe (106) passes through the symmetric mating joints (112).

3. The geotechnical energy storage cyclic heat exchange system according to claim 2, wherein: A half-piece sleeve (113) is sleeved on the side of the symmetric mating joint (112) close to the outlet pipe (106). One end of the half-piece sleeve (113) is provided with a flange (114). A sealing gasket (115) is provided on one side of the flange (114). External threads are provided on the outer circumferential surface of the half-piece sleeve (113) far from the flange (114). The external threads on the symmetric half-piece sleeves (113) cooperate with each other to form a complete external thread. Symmetric grooves are provided on the side of the half-piece sleeve (113) facing the outlet pipe (106). A sealing rubber strip (116) is connected in the grooves.

4. The geotechnical energy storage cyclic heat exchange system according to claim 3, wherein: A connection cover (117) is threadedly connected to the side of the half-piece sleeve (113) far from the flange (114). The connection cover (117) is sleeved outside the outlet pipe (106). An extrusion part (118) is provided on the side of the connection cover (117) close to the mating joint (112). An annular groove is provided on one side of the extrusion part (118). A first annular sealing ring (119) is connected in the annular groove. An extrusion ring (120) is provided on the side of the mating joint (112) close to the connection cover (117). The extrusion ring (120) can exert an extrusion effect on the first annular sealing ring (119).

5. The geotechnical energy storage cyclic heat exchange system according to claim 4, wherein: A second annular sealing ring (121) is connected to the inner side of the connection cover (117). The second annular sealing ring (121) is in contact with the side of the half-piece sleeve (113) close to the external thread.

6. The geotechnical energy storage cyclic heat exchange system according to claim 2, wherein: Symmetric reinforcing ribs (122) are connected to the inner circumferential surfaces of the support ring (109) and the top cover (111).

Images