Heating system coupled with terrestrial heat at different depths

Abstract

The utility model discloses a heating system coupled with terrestrial heat at different depths, which relates to the technical field of terrestrial heat devices and comprises a user side, a shallow terrestrial heat system, a middle terrestrial heat system and a deep terrestrial heat system. And the other end of the tail end water supply line is sequentially connected with the shallow geothermal system, the middle geothermal system and the deep geothermal system. According to the heating system coupled with the terrestrial heat at different depths, stable heat supply can be kept for the user side through the terrestrial heat well heating system at different depths, the diversity of heat supply is improved, the heating system has the function of heat exchange and refrigeration for the user side in summer, the purpose of the terrestrial heat well is improved, and meanwhile, the heating system is suitable for popularization and application. The superficial layer pipeline can be integrated on the middle-deep layer pipeline, the construction difficulty is reduced, the production cost is reduced, and the heat exchange efficiency of the superficial layer heat exchange pipeline is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of geothermal devices, and more specifically to a heating system coupling geothermal energy at different depths. Background Art

[0002] A heat exchange geothermal well is a system that uses underground heat energy for heat exchange. It is mainly used for the development and utilization of geothermal energy, especially in the fields of heating, hot water supply and power generation. This type of geothermal well is designed to extract heat from underground reservoirs efficiently and sustainably while reducing the impact on the environment. The types of geothermal energy currently developed and utilized are mainly divided into shallow geothermal energy, middle geothermal energy and deep geothermal energy. In the utilization of geothermal resources, the buried pipe system has the advantages of not being restricted by groundwater resources, no pollution to the environment, not being affected by external factors such as seasons and climate, and good system stability.

[0003] However, the shallow buried pipe system now occupies a large area, and the long operation time is easy to cause the underground cold and heat imbalance, affecting the energy efficiency of the system; and the medium-deep underground heat exchange system has the problem of high well drilling cost and large initial investment. At the same time, the existing heating system mostly uses a single heat source for heating, and the heat source form is single and the heat source stability is poor. Therefore, some manufacturers will combine various forms of energy for use. For example, the Chinese patent with application number 202120459648.0 discloses a multi-tube heat exchanger for medium-deep geothermal wells, the structure of which includes a shallow geothermal heat exchanger buried more than 200m underground and a medium-deep geothermal heat exchanger buried more than 3000m underground; the medium-deep geothermal heat exchanger and the shallow geothermal heat exchanger are both provided with inner and outer casings, and the shallow geothermal heat exchanger is sleeved on the outside of the medium-deep geothermal heat exchanger. Although the multi-tube heat exchanger used in deep geothermal wells can exchange heat in winter and cool in summer, it still has the following problems:

[0004] The shallow heat exchanger is mounted on the deep heat exchanger. The installation hole of the shallow heat exchanger is larger than the hole of the deep heat exchanger. This requires opening a hole for a shallow heat exchange well on the basis of the original deep heat exchange well. This not only increases the difficulty of drilling, but also increases the difficulty of installation and increases production costs.

[0005] Therefore, it is necessary to propose a heating system that couples geothermal energy at different depths to solve the above problems. Utility Model Content

[0006] 1. Technical issues to be resolved

[0007] In view of the above problems, the utility model provides a heating system that couples geothermal energy at different depths; it has the function of improving the stability of heating in winter, and can perform heat exchange and cooling for the user end in summer. At the same time, the shallow geothermal well pipelines are integrated into the medium and deep pipelines. When installing the shallow geothermal pipes, there is no need to expand the original wellway, which reduces the difficulty of construction.

[0008] (II) Technical solution

[0009] In order to achieve the above-mentioned purpose, the utility model specifically adopts the following technical solutions:

[0010] A heating system coupled with geothermal energy at different depths, comprising a user end, a shallow geothermal system, a middle geothermal system and a deep geothermal system, wherein the user end is connected to a terminal water supply line, and the other end of the terminal water supply line is connected to the shallow geothermal system, the middle geothermal system and the deep geothermal system in sequence;

[0011] A shallow geothermal heat pump host is connected between the terminal water supply line and the shallow geothermal system. The shallow geothermal system includes a shallow circulation pipeline and a shallow geothermal circulation pump connected to the shallow circulation pipeline, and a shallow geothermal well pipeline. The shallow geothermal circulation pump is located at the water inlet end of the shallow geothermal heat pump host.

[0012] A middle-layer geothermal heat pump host is connected between the terminal water supply line and the middle-layer geothermal system. The middle-layer geothermal system includes a middle-layer circulation pipeline and a middle-layer geothermal circulation pump connected to the middle-layer circulation pipeline, and a middle-layer geothermal well pipeline. The middle-layer geothermal circulation pump is located at the water inlet end of the middle-layer geothermal heat pump host.

[0013] A deep geothermal heat pump host is connected between the terminal water supply line and the deep geothermal system. The deep geothermal system includes a deep circulation pipeline and a deep geothermal circulation pump connected to the deep circulation pipeline, and a deep geothermal well pipeline. The deep geothermal circulation pump is located at the water inlet end of the deep geothermal heat pump host.

[0014] The terminal water supply line is connected with a terminal circulation pump, and the terminal circulation pump is located at the water inlet end of the user end.

[0015] Preferably, the shallow geothermal well pipeline includes a fixed pipe and a coil, an annular plate is provided on the outer annular surface of the fixed pipe, a cavity is formed between the fixed pipe and the annular plate, the coil is spirally arranged in the cavity, and the cavity is filled with heat-conducting liquid.

[0016] Preferably, a support plate is connected between the ring plate and the fixed pipe, the coil is fixed on the support plate, and holes for liquid circulation are provided on the support plate.

[0017] Preferably, two ends of the coil are connected with a water inlet pipe and a water outlet pipe, and a curved portion is provided at the bottom of the coil.

[0018] Preferably, the inner annular surface of the fixed pipe is connected with a support seat, the support seat is sleeved on the water inlet pipe and the water outlet pipe, and the top of the support seat is provided with a water-conducting inclined surface.

[0019] Preferably, the fixed pipe is installed on the casing of the middle-layer geothermal well pipe or the deep-layer geothermal well pipe, the outer annular surface of the ring plate is the same as the outer annular surface of the fixed pipe, and the outer annular surface of the fixed pipe is the same as the outer annular surface of the middle-layer geothermal well pipe or the deep-layer geothermal well pipe.

[0020] Compared with the prior art, the beneficial effects of the utility model are:

[0021] 1. This device sets up shallow geothermal system, middle geothermal system and deep geothermal system in sequence at the other end of the terminal water supply line. Through the geothermal well heating system of different depths, it can maintain a stable heat supply for the user end, improve the diversity of heating, and at the same time, it has the function of heat exchange and cooling for the user end in summer, which improves the use of geothermal wells.

[0022] 2. The device is provided with a fixed pipe that can be fixed on the medium-deep pipeline. The fixed pipe has the same diameter as the medium-deep pipeline and can be moved together and lowered into the geothermal well. There is no need to expand the pipeline again on the basis of the medium-deep well to accommodate the shallow geothermal well pipeline. It has the function of integrating the shallow pipeline on the medium-deep pipeline, reducing the construction difficulty and production cost. At the same time, it improves the efficiency of the shallow heat exchange pipeline during heat exchange. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the main structure of the utility model;

[0024] Figure 2 It is a schematic diagram of the pipeline locations of the shallow geothermal system and the deep geothermal system in the utility model;

[0025] Figure 3 It is a three-dimensional cross-sectional schematic diagram of the connection structure between the fixed pipe and the coil pipe in the utility model;

[0026] Figure 4 It is a three-dimensional schematic diagram of the connection structure between the coil pipe and the support plate in the utility model.

[0027] Reference numerals:

[0028] 110, user end; 120, shallow geothermal system; 130, middle geothermal system; 140, deep geothermal system; 150, terminal water supply line; 121, shallow geothermal heat pump host; 122, shallow circulation pipeline; 123, shallow geothermal circulation pump; 124, shallow geothermal well pipeline; 131, middle geothermal heat pump host; 132, middle circulation pipeline; 133, middle geothermal circulation pump; 1 34. Middle-layer geothermal well pipeline; 141. Deep geothermal heat pump main unit; 142. Deep circulation pipeline; 143. Deep geothermal circulation pump; 144. Deep geothermal well pipeline; 160. Terminal circulation pump; 201. Fixed pipe; 202. Coil; 203. Ring plate; 204. Cavity; 205. Support plate; 206. Water inlet pipe; 207. Water outlet pipe; 208. Arc part; 209. Support seat. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] See also Figure 1-4 A heating system coupling geothermal energy at different depths includes a user end 110, a shallow geothermal system 120, a middle geothermal system 130 and a deep geothermal system 140. A heat pump host is arranged between a terminal water supply line 150 and the shallow geothermal system 120, the middle geothermal system 130 and the deep geothermal system 140. The heat pump host transfers heat at one end to the terminal water supply line 150. The terminal water supply line 150 supplies heat to the user end 110. The user end 110 is connected to the terminal water supply line 150. The water supply line 150, and the other end of the terminal water supply line 150 is connected to the shallow geothermal system 120, the middle geothermal system 130 and the deep geothermal system 140 in sequence, the fixed pipe 201 of the shallow geothermal system 120 is arranged on the geothermal well pipes of the middle geothermal system 130 and the deep geothermal system 140, and the pipe diameter of the shallow geothermal system 120 is the same as the pipe diameter of the middle geothermal system 130 and the deep geothermal system 140, avoiding the need to enlarge the geothermal well hole;

[0031] refer to Figure 2A shallow geothermal heat pump host 121 is connected between the terminal water supply line 150 and the shallow geothermal system 120. The shallow geothermal heat pump host 121 is used to transport the heat after heat exchange in the shallow geothermal system 120 to the terminal water supply line 150. The shallow geothermal system 120 includes a shallow circulation pipeline 122 and a shallow geothermal circulation pump 123 and a shallow geothermal well pipeline 124 connected to the shallow circulation pipeline 122. The shallow circulation pipeline 122 is used to connect the shallow geothermal heat pump host 121 and the shallow geothermal well pipeline 124 for transporting shallow circulating water. The shallow geothermal circulation pump 123 is located at the water inlet end of the shallow geothermal heat pump host 121.

[0032] refer to Figure 1 A middle-layer geothermal heat pump host 131 is connected between the terminal water supply line 150 and the middle-layer geothermal system 130. The middle-layer geothermal heat pump host 131 is used to transport the heat after heat exchange in the middle-layer geothermal system 130 to the terminal water supply line 150. The middle-layer geothermal system 130 includes a middle-layer circulation pipeline 132 and a middle-layer geothermal circulation pump 133 and a middle-layer geothermal well pipeline 134 connected to the middle-layer circulation pipeline 132. The middle-layer circulation pipeline 132 is used to connect the middle-layer geothermal heat pump host 131 and the middle-layer geothermal well pipeline 134 for transporting middle-layer circulation water. The middle-layer geothermal circulation pump 133 is located at the water inlet end of the middle-layer geothermal heat pump host 131.

[0033] refer to Figure 2 A deep geothermal heat pump host 141 is connected between the terminal water supply line 150 and the deep geothermal system 140. The deep geothermal heat pump host 141 is used to transport the heat after heat exchange in the deep geothermal system 140 to the terminal water supply line 150. The deep geothermal system 140 includes a deep circulation pipeline 142 and a deep geothermal circulation pump 143 and a deep geothermal well pipeline 144 connected to the deep circulation pipeline 142. The deep circulation pipeline 142 is used to connect the deep geothermal heat pump host 141 and the deep geothermal well pipeline 144 for transporting deep circulation water. The deep geothermal circulation pump 143 is located at the water inlet end of the deep geothermal heat pump host 141.

[0034] refer to Figure 1 The terminal water supply line 150 is connected to a terminal circulation pump 160. The shallow geothermal circulation pump 123, the middle geothermal circulation pump 133, the deep geothermal circulation pump 143 and the terminal circulation pump 160 are all located at the water inlet end of the heat exchanger. The terminal circulation pump 160 is located at the water inlet end of the user end 110.

[0035] Specifically, refer to Figure 3 and Figure 4The shallow geothermal well pipeline 124 includes a fixed pipe 201 and a coil 202. The fixed pipe 201 can be fixed on the heat exchange pipe of the middle geothermal well pipeline 134 or the deep geothermal well pipeline 144. It has the same diameter and can be lowered into the geothermal well well along with the middle or deep geothermal well pipeline. An annular plate 203 is arranged on the outer annular surface of the fixed pipe 201. A cavity 204 is formed between the fixed pipe 201 and the annular plate 203. The coil 202 exchanges heat with the external rock formation through the heat-conducting liquid in the cavity 204. The coil 202 is spirally arranged in the cavity 204, and the cavity 204 is filled with heat-conducting liquid.

[0036] Specifically, refer to Figure 3 and Figure 4 A support plate 205 is connected between the ring plate 203 and the fixed tube 201. The support plate 205 is used to support the external ring plate 203 and also to support the coil 202. A plurality of holes are provided on the support plate 205 for the flow of heat-conducting liquid. The coil 202 is fixed on the support plate 205. The support plate 205 is provided with holes for liquid circulation.

[0037] Specifically, refer to Figure 3 and Figure 4 The two ends of the coil 202 are connected with an inlet pipe 206 and an outlet pipe 207. The circulating water in the shallow circulation pipeline 122 enters the coil 202 through the inlet pipe 206, then exchanges heat with the surrounding rock formations through the heat transfer liquid, and finally returns to the shallow circulation pipeline 122 through the outlet pipe 207. The bottom of the coil 202 is provided with an arc portion 208, and the arc portion 208 is arranged upward, which increases the contact area between the heat transfer liquid and the coil 202 and improves the heat exchange efficiency.

[0038] Specifically, refer to Figure 3 and Figure 4 The inner annular surface of the fixed pipe 201 is connected to a support seat 209, and the support seat 209 is used to support the water inlet pipe 206 and the water outlet pipe 207. An inclined surface is provided on the top to guide the flowing water to both sides. The support seat 209 is sleeved on the water inlet pipe 206 and the water outlet pipe 207, and a water-guiding inclined surface is provided on the top of the support seat 209.

[0039] Specifically, refer to Figure 3 and Figure 4 The fixed pipe 201 is installed on the casing of the middle-layer geothermal well pipe 134 or the deep-layer geothermal well pipe 144. The middle-deep heat exchange pipe is composed of an inner pipe and an outer pipe. The fixed pipe 201 can be installed on the casing of the middle-layer geothermal well pipe 134 or the deep-layer geothermal well pipe 144 and move with it. The outer ring surface of the ring plate 203 is the same as the outer ring surface of the fixed pipe 201, and the outer ring surface of the fixed pipe 201 is the same as the outer ring surface of the middle-layer geothermal well pipe 134 or the deep geothermal well pipe 144.

[0040] In this embodiment, reference 1 and Figure 2 The shallow geothermal system 120, the middle geothermal system 130 and the deep geothermal system 140 can transfer heat to the terminal water supply line 150 through the shallow geothermal heat pump main unit 121, the middle geothermal heat pump main unit 131 and the deep geothermal heat pump main unit 141. The terminal water supply line 150 is connected to the user end 110 for the user end 110 to use the heat.

[0041] In winter, the deep geothermal system 140 is first activated to provide heating for the user end 110. As the weather gets colder, the middle geothermal system 130 is simultaneously activated to provide heating for the user end 110. Finally, the shallow geothermal system 120 is activated. Through the joint cooperation of the shallow geothermal system 120, the middle geothermal system 130 and the deep geothermal system 140, the stability of the heating is guaranteed.

[0042] In summer, the shallow geothermal system 120 and the middle geothermal system 130 are used in turn to exchange heat with the user end 110, which can cool the user end 110. At the same time, the heat after the heat exchange can restore the formation temperature and supplement the ground heat storage for use in winter.

[0043] When drilling the middle-layer geothermal well pipe 134 and the deep-layer geothermal well pipe 144, the fixed pipe 201 can be fixed on the heat exchange pipe of the middle-layer geothermal well pipe 134 or the deep-layer geothermal well pipe 144. The diameter of the fixed pipe 201 is the same as that of the middle-layer geothermal well pipe 134 and the deep-layer geothermal well pipe 144, and can be lowered into the geothermal well hole together with the middle-layer or deep-layer geothermal well pipe, thereby avoiding the need to expand the wellbore when installing the shallow-layer geothermal well pipe 124.

[0044] When using, refer to Figure 3 and Figure 4 The circulating water in the shallow circulation pipeline 122 enters the coil 202 through the water inlet pipe 206 , and the coil 202 exchanges heat with the surrounding rock formation through the heat-conducting liquid in the cavity 204 , and returns to the shallow circulation pipeline 122 through the water outlet pipe 207 after the heat exchange.

[0045] The above-mentioned implementation modes are only preferred implementation modes of the present invention, and cannot be used to limit the protection scope of the present invention. Any non-substantial changes and substitutions made by technicians in this field on the basis of the present invention shall fall within the scope of protection required by the present invention.

Claims

1. A heating system coupling geothermal energy at different depths, characterized in that: The system comprises a user end (110), a shallow geothermal system (120), a middle geothermal system (130) and a deep geothermal system (140); the user end (110) is connected to a terminal water supply line (150), and the other end of the terminal water supply line (150) is connected to the shallow geothermal system (120), the middle geothermal system (130) and the deep geothermal system (140) in sequence; A shallow geothermal heat pump main unit (121) is connected between the terminal water supply line (150) and the shallow geothermal system (120); the shallow geothermal system (120) comprises a shallow circulation pipeline (122), a shallow geothermal circulation pump (123) connected to the shallow circulation pipeline (122), and a shallow geothermal well pipeline (124); the shallow geothermal circulation pump (123) is located at the water inlet end of the shallow geothermal heat pump main unit (121); A middle-layer geothermal heat pump main unit (131) is connected between the terminal water supply line (150) and the middle-layer geothermal system (130); the middle-layer geothermal system (130) comprises a middle-layer circulation pipeline (132), a middle-layer geothermal circulation pump (133) connected to the middle-layer circulation pipeline (132), and a middle-layer geothermal well pipeline (134); the middle-layer geothermal circulation pump (133) is located at the water inlet end of the middle-layer geothermal heat pump main unit (131); A deep geothermal heat pump main unit (141) is connected between the terminal water supply line (150) and the deep geothermal system (140); the deep geothermal system (140) comprises a deep circulation pipeline (142), a deep geothermal circulation pump (143) connected to the deep circulation pipeline (142), and a deep geothermal well pipeline (144); the deep geothermal circulation pump (143) is located at the water inlet end of the deep geothermal heat pump main unit (141); The terminal water supply line (150) is connected to a terminal circulation pump (160), and the terminal circulation pump (160) is located at the water inlet end of the user end (110).

2. A heating system coupled with geothermal energy at different depths according to claim 1, characterized in that: The shallow geothermal well pipeline (124) comprises a fixed pipe (201) and a coil (202); an annular plate (203) is arranged on the outer annular surface of the fixed pipe (201); a cavity (204) is formed between the fixed pipe (201) and the annular plate (203); the coil (202) is spirally arranged in the cavity (204); and the cavity (204) is filled with a heat-conducting liquid.

3. A heating system coupled with geothermal energy at different depths according to claim 2, characterized in that: A support plate (205) is connected between the annular plate (203) and the fixed tube (201), the coil tube (202) is fixed on the support plate (205), and holes for liquid circulation are provided on the support plate (205).

4. A heating system coupled with geothermal energy at different depths according to claim 2, characterized in that: The two ends of the coil (202) are connected to a water inlet pipe (206) and a water outlet pipe (207), and the bottom of the coil (202) is provided with a curved surface portion (208).

5. A heating system coupled with geothermal energy at different depths according to claim 4, characterized in that: The inner annular surface of the fixed pipe (201) is connected to a support seat (209), the support seat (209) is sleeved on the water inlet pipe (206) and the water outlet pipe (207), and the top of the support seat (209) is provided with a water-guiding inclined surface.

6. A heating system coupled with geothermal energy at different depths according to claim 5, characterized in that: The fixed pipe (201) is installed on the casing of a middle-layer geothermal well pipeline (134) or a deep-layer geothermal well pipeline (144); the outer annular surface of the ring plate (203) is the same as the outer annular surface of the fixed pipe (201); and the outer annular surface of the fixed pipe (201) is the same as the outer annular surface of the middle-layer geothermal well pipeline (134) or the deep-layer geothermal well pipeline (144).

Images