Thermophysical property testing equipment for medium-deep geothermal energy through constant-temperature method

Abstract

The utility model discloses equipment for testing thermophysical properties of medium-deep geothermal energy by a constant-temperature method, which relates to the field of geothermal energy testing and comprises an air source heat pump assembly, a pump set assembly and a geothermal data measuring assembly which are sequentially connected from right to left by pipelines. The geothermal energy heat extraction capacity testing device can adapt to geothermal energy heat extraction capacity testing of most regions throughout the country, the working environment temperature ranges from-15 DEG C to 52 DEG C, the geothermal energy heat extraction capacity testing device can adapt to heat extraction capacity testing in any environment and is not limited by the environment temperature, the testing heat extraction and extraction load is smaller than or equal to 130 kW, and the testing efficiency is high. And working under different loads in a power range of 1-130kW can be realized. The test power can be expanded by connecting a plurality of test devices in parallel, the test temperature range of the test devices is 0-100 DEG C, and full coverage of a middle-deep layer double-temperature buried pipe heat exchange system and a shallow layer geothermal energy heat exchange capability test is achieved.

Description

Technical Field

[0001] The present invention relates to the field of geothermal energy testing, and in particular to a thermophysical property testing device for medium-deep geothermal energy using a constant temperature method. Background Art

[0002] Currently, shallow geothermal energy is the most widely used in my country. Shallow geothermal wells typically have a depth of 100 to 300 meters. For shallow geothermal data testing, specifically shallow rock and soil thermal response testing, my country already has numerous shallow geothermal thermophysical property testers capable of performing these tests. However, my country currently lacks mature testing equipment for medium- and deep-layer geothermal testing. Subsequent geothermal energy utilization will undoubtedly shift towards medium- and deep-layer geothermal energy utilization.

[0003] Medium-deep buried pipe ground-source heat pump technology is a major means of utilizing deep geothermal energy. It utilizes a closed-loop system, extracting heat without using water. It uses the deep rock mass as the heat source. The heat carrier, typically working water, in the deep geothermal heat exchanger exchanges heat with the rock mass, extracting heat from the underground rock mass. Rock mass temperatures typically exceed 40°C at depths between 1,000 and 3,000 meters below the surface, while those within 200 meters are typically below 25°C. For deep heat extraction, if the working water reaches a sufficient temperature for heating after heat exchange with the underground rock mass, the deep buried pipe heat exchange system is used to directly provide heat. If the water temperature is too high for direct heating, a heat pump unit is used to raise the temperature for heating.

[0004] As a new form of geothermal energy utilization, ground-source heat pump technology using medium- to deep-seated underground pipes is still in its infancy. Research on this technology primarily focuses on theoretical models of heat exchange in medium- to deep-seated underground pipes, including heat exchange mechanisms, short- and long-term heat exchange performance, and heat exchange capacity. In actual engineering applications, this technology primarily serves as a demonstration and exploratory test. A complete, systematic, and standardized implementation process, from engineering survey and design to construction acceptance and overall operational adjustment, has yet to be established.

[0005] The thermal properties of the rock and soil surrounding medium- to deep-seated buried pipes (including rock and soil temperature, heat transfer performance, and heat capacity) fundamentally determine the heat transfer capacity, system energy efficiency, and project costs of medium- to deep-seated buried pipe heat exchangers. These properties are the primary parameters determining the economic viability and energy efficiency of medium- to deep-seated buried pipe ground-source heat pumps. Currently, research and technical methods for understanding the thermal properties of the rock and soil surrounding medium- to deep-seated buried pipes are still lacking. Therefore, the industry urgently needs equipment capable of conducting medium- to deep-seated geothermal energy testing. Summary of the Invention

[0006] In response to the deficiencies in the existing technology, the present invention provides a medium-deep geothermal energy constant temperature method thermal physical property testing equipment, which solves the technical problem that the existing research on the thermal performance of rock and soil around medium-deep buried pipes and the obtained technical methods are still blank.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a medium-deep geothermal energy constant temperature method thermal physical property testing equipment, including an air source heat pump component, a pump group component and a geothermal data measurement component, the air source heat pump component, the pump group component and the geothermal data measurement component are connected by pipelines from right to left in sequence, a flow dividing and mixing regulating valve is connected between the pump group component and the geothermal data measurement component, a water supply valve is connected to one side of the flow dividing and mixing regulating valve, a water supply valve is connected to one side of the water supply valve, an electric heater bypass valve is connected to one side of the water treatment instrument, the electric heater bypass valve is connected to the air source heat pump component, an electric heater water inlet valve and an electric heater water outlet valve are connected on both sides of the electric heater bypass valve, and an electric heater is connected between the electric heater water inlet valve and the electric heater water outlet valve.

[0008] Preferably, the air source heat pump assembly includes an air source heat pump unit, and the input end and output end of the air source heat pump unit are respectively connected to the heat pump unit water inlet valve and the heat pump unit water outlet valve, a heat pump unit bypass valve is connected between the heat pump unit water inlet valve and the heat pump unit water outlet valve, one side of the heat pump unit bypass valve is connected to a first remote temperature gauge, one side of the first remote temperature gauge is connected to a first remote pressure gauge, the first remote pressure gauge is connected to the electric heater bypass valve, the other side of the heat pump unit bypass valve is connected to a second remote temperature gauge, one side of the second remote temperature gauge is connected to a second remote pressure gauge, and the second remote pressure gauge is connected to the pump group assembly.

[0009] Preferably, the pump group assembly includes a first circulating water pump and a second circulating water pump, the first circulating water pump and the second circulating water pump are connected in parallel, the first circulating water pump and the second circulating water pump are respectively connected to water pump expansion joints on both sides, the water pump expansion joints are respectively connected to a first on-site pressure gauge and a drain valve on one side, the first on-site pressure gauge and the drain valve are respectively connected to a check valve and a decontamination valve group on one side, the check valve and the decontamination valve group are respectively connected to a water pump shut-off valve on one side, and a second on-site pressure gauge is connected in series between the water pump shut-off valves close to the check valve.

[0010] Preferably, the geothermal data measurement component includes a geothermal well, in which a heat exchanger is fixedly installed, the heat exchanger input end is connected to a heat exchanger inlet valve, the heat exchanger inlet valve is connected to a second on-site pressure gauge, a heat exchanger pipeline remote pressure gauge and a heat exchanger pipeline remote temperature gauge are connected between the heat exchanger inlet valve and the second on-site pressure gauge, the heat exchanger output end is connected to a heat exchanger outlet valve, one side of the heat exchanger outlet valve is connected to a decontamination valve group, one side of the decontamination valve group is connected to a heat exchanger pipeline remote pressure gauge, one side of the heat exchanger pipeline remote pressure gauge is connected to a heat exchanger pipeline remote temperature gauge, one side of the heat exchanger pipeline remote temperature gauge is connected to a flow meter, and the flow meter is connected to the flow dividing and mixing regulating valve.

[0011] Preferably, the decontamination valve group includes a Y-type filter, and the front and rear sides of the Y-type filter are respectively connected to filter pressure gauges.

[0012] Preferably, the first circulating water pump and the second circulating water pump are 15m 3 / h and 10m 3 / h, and the first circulating water pump and the second circulating water pump are made of stainless steel.

[0013] Beneficial effects

[0014] This invention provides a device for testing the thermal properties of medium- and deep-layer geothermal energy using a constant-temperature method. This device addresses the existing lack of research and technical methods for the thermal properties of the rock and soil surrounding medium- and deep-layer buried pipes. The device is suitable for testing geothermal heat extraction capacity in most areas of China, operating in ambient temperatures ranging from -15°C to 52°C. It can also test heat removal capacity in any environment, regardless of ambient temperature. The test heat removal load is ≤130kW, and it can operate at various loads within a power range of 1 to 130kW. The test power can be expanded by connecting multiple test devices in parallel, and the test temperature range is 0-100°C, enabling comprehensive coverage of heat exchange capacity testing for medium- and deep-layer dual-temperature buried pipe heat exchange systems and shallow geothermal energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic structural diagram of a thermophysical property testing device for medium-deep geothermal energy using a constant temperature method as described in the present invention.

[0016] In the figure: 100 - air source heat pump assembly; 101 - air source heat pump unit; 102 - heat pump unit water inlet valve; 103 - heat pump unit water outlet valve; 104 - heat pump unit bypass valve; 105 - first remote temperature gauge; 106 - first remote pressure gauge; 107 - second remote temperature gauge; 108 - second remote pressure gauge;

[0017] 200-Pump assembly; 201-First circulating water pump; 202-Second circulating water pump; 203-Water pump shut-off valve; 204-Sewage removal valve assembly; 205-Drain valve; 206-Water pump expansion joint; 207-First on-site pressure gauge; 208-Check valve; 209-Second on-site pressure gauge;

[0018] 300 - Geothermal data measurement system; 301 - Heat exchanger inlet valve; 302 - Geothermal well; 303 - Heat exchanger; 304 - Heat exchanger outlet valve; 305 - Heat exchanger pipe remote temperature gauge; 306 - Heat exchanger pipe remote pressure gauge; 307 - Flow meter;

[0019] 401-water treatment instrument; 402-electric heater; 403-dividing and mixing flow regulating valve; 404-water supply valve; 405-electric heater water inlet valve; 406-electric heater water outlet valve; 407-electric heater bypass valve. DETAILED DESCRIPTION

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] See also Figure 1 The present invention provides a technical solution: a medium-deep geothermal energy constant temperature method thermal property testing equipment, including an air source heat pump component 100, a pump group component 200 and a geothermal data measurement component 300, the air source heat pump component 100, the pump group component 200 and the geothermal data measurement component 300 are connected by pipelines from right to left, a flow dividing and mixing regulating valve 403 is connected between the pump group component 200 and the geothermal data measurement component 300, one side of the flow dividing and mixing regulating valve 403 is connected to a water supply valve 404, one side of the water supply valve 404 is connected to a water treatment instrument 401, one side of the water treatment instrument 401 is connected to an electric heater bypass valve 407, the electric heater bypass valve 407 is connected to the air source heat pump component 100, and the electric heater bypass valve 407 is respectively connected to an electric heater water inlet valve 405 and an electric heater water outlet valve 406 on both sides, and an electric heater 402 is connected between the electric heater water inlet valve 405 and the electric heater water outlet valve 406.

[0022] This embodiment is further configured as follows: the air source heat pump assembly 100 includes an air source heat pump unit 101, and the input end and output end of the air source heat pump unit 101 are respectively connected to a heat pump unit water inlet valve 102 and a heat pump unit water outlet valve 103, a heat pump unit bypass valve 104 is connected between the heat pump unit water inlet valve 102 and the heat pump unit water outlet valve 103, one side of the heat pump unit bypass valve 104 is connected to a first remote temperature gauge 105, one side of the first remote temperature gauge 105 is connected to a first remote pressure gauge 106, the first remote pressure gauge 106 is connected to the electric heater bypass valve 407, the other side of the heat pump unit bypass valve 104 is connected to a second remote temperature gauge 107, one side of the second remote temperature gauge 107 is connected to a second remote pressure gauge 108, and the second remote pressure gauge 108 is connected to the pump group assembly 200.

[0023] This embodiment is further configured as follows: the pump group assembly 200 includes a first circulating water pump 201 and a second circulating water pump 202, the first circulating water pump 201 and the second circulating water pump 202 are connected in parallel, the first circulating water pump 201 and the second circulating water pump 202 are respectively connected to water pump expansion joints 206 on both sides, the water pump expansion joint 206 is respectively connected to a first on-site pressure gauge 207 and a drain valve 205 on one side, the first on-site pressure gauge 207 and the drain valve 205 are respectively connected to a check valve 208 and a decontamination valve group 204 on one side, the check valve 208 and the decontamination valve group 204 are respectively connected to a water pump shut-off valve 203 on one side, and a second on-site pressure gauge 209 is connected in series between the water pump shut-off valve 203 near the check valve 208.

[0024] This embodiment is further configured as follows: the geothermal data measurement component 300 includes a geothermal well 302, a heat exchanger 303 is fixedly installed in the geothermal well 302, the input end of the heat exchanger 303 is connected to a heat exchanger inlet valve 301, the heat exchanger inlet valve 301 is connected to a second local pressure gauge 209, and a heat exchanger pipeline remote pressure gauge 306 and a heat exchanger pipeline remote temperature gauge 305 are connected between the heat exchanger inlet valve 301 and the second local pressure gauge 209. The output end of the heat exchanger 303 is connected to a heat exchanger outlet valve 304, one side of the heat exchanger outlet valve 304 is connected to a decontamination valve group 204, one side of the decontamination valve group 204 is connected to a heat exchanger pipeline remote pressure gauge 306, one side of the heat exchanger pipeline remote pressure gauge 306 is connected to a heat exchanger pipeline remote temperature gauge 305, one side of the heat exchanger pipeline remote temperature gauge 305 is connected to a flow meter 307, and the flow meter 307 is connected to the sub-mixing flow regulating valve 403.

[0025] This embodiment is further configured such that the decontamination valve group 204 includes a Y-type filter, and filter pressure gauges are respectively connected to the front and rear sides of the Y-type filter.

[0026] This embodiment is further configured as follows: the first circulating water pump 201 and the second circulating water pump 202 are 15m 3 / h and 10m 3 / h, and the first circulating water pump 201 and the second circulating water pump 202 are made of stainless steel.

[0027] The detailed connection means are well-known technologies in this field. The following mainly introduces the working principle and process. The specific operations are as follows.

[0028] Example 1: Due to the high temperature of mid-deep geothermal, it is currently mainly used for heating or providing heat source for heating or drying other materials. Therefore, the utilization of mid-deep geothermal is mainly to extract heat from the geothermal (absorb heat). At this time, the heat release capacity of the geothermal is tested. Figure 1 When testing the heat exchange capacity of deep geothermal energy, since the geothermal temperature is usually higher than 40°C or even reaches 100°C, an air source heat pump unit is needed to cool the working water. The test process is as follows:

[0029] Open the water supply valve 404, the electric heater bypass valve 407, the heat pump unit water inlet valve 102, the heat pump unit water outlet valve 103, the heat exchanger inlet valve 301, and the heat exchanger outlet valve 304 in sequence, and close the electric heater water inlet valve 405, the electric heater water outlet valve 406, and the heat pump unit bypass valve 104 in sequence. Then start the pump assembly 200 and the air source heat pump unit 101, and set the outlet water temperature of the heat pump unit to a certain temperature value, for example, to 40°C. The 40°C working medium water is pressurized and transported to the heat exchanger 303 through the pump assembly. The working medium water is heated by the deep geothermal heat and its temperature rises. By recording the readings of the remote temperature meter 305 and the flow meter 307 of the heat exchanger inlet and outlet pipes, the heat extracted from the underground rock and soil can be calculated, and then the heat release capacity of the deep geothermal energy system can be calculated. In this operating condition, the electric heater 402 is mainly decoupled and the air source heat pump assembly 100 is put into operation.

[0030] Example 2: As for the utilization of shallow geothermal energy, due to its low temperature, it cannot be used directly for heating. Therefore, in the current specific application, water (ground) source heat pump units are usually installed to "transfer" the heat in the building to the underground rock and soil in summer to achieve air conditioning and cooling of the building. In winter, the heat in the underground rock and soil is "transferred" to the building for heating. Figure 1A medium-deep geothermal energy constant temperature method thermal physical property testing equipment. When conducting shallow geothermal energy heat exchange capacity testing, that is, conducting shallow rock and soil thermal response experiments, since the shallow geothermal temperature is usually lower than 25°C, the working fluid water temperature is adjusted to the set temperature through the electric heater 402 or the air source heat pump component 100: when simulating winter operating conditions, the working fluid water temperature can generally be set to 15°C, at which time the geothermal heat release capacity is tested; when simulating summer conditions, the working fluid water temperature is set to 30°C, at which time the geothermal heat absorption capacity is tested.

[0031] When simulating winter working conditions, an air source heat pump unit is needed to cool the working water, that is, to perform refrigeration. The test process is the same as the aforementioned medium and deep geothermal test process. The electric heater 402 is decoupled and the air source heat pump assembly 100 is put into operation.

[0032] When simulating summer working conditions, the air source heat pump assembly 100 needs to be stopped and the working medium water temperature is heated to 30°C by the electric heater 402. The test process is as follows:

[0033] The water supply valve 404, electric heater inlet valve 405, electric heater outlet valve 406, heat pump bypass valve 104, heat exchanger inlet valve 301, and heat exchanger outlet valve 304 are sequentially opened. The electric heater bypass valve 407, heat pump inlet valve 102, and heat pump outlet valve 103 are then sequentially closed. The pump assembly 200 and electric heater 402 are then started, and the outlet water temperature of electric heater 402 is set to a certain value, for example, 30°C. The 30°C working water is pressurized and transported to the heat exchanger 303 by the pump assembly. The working water absorbs heat from the deep-seated geothermal energy, cooling it and lowering its temperature. By recording the readings of the remote temperature gauges 305 and flow meter 307 on the heat exchanger inlet and outlet pipes, the amount of heat released from the working water to the underground rock and soil can be calculated, thereby calculating the heat release capacity of the shallow geothermal energy system. This operating condition primarily involves the electric heater 402 being operational and the air-source heat pump assembly 100 being decoupled.

[0034] It should be noted that, in this document, relational terms such as first and second, etc. are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

Claims

1. A medium-deep geothermal energy constant temperature method thermal property testing equipment, comprising an air source heat pump component (100), a pump group component (200) and a geothermal data measurement component (300), characterized in that: The air source heat pump assembly (100), the pump group assembly (200) and the geothermal data measurement assembly (300) are connected in sequence by pipelines from right to left. A split-mixing flow regulating valve (403) is connected between the pump group assembly (200) and the geothermal data measurement assembly (300). One side of the split-mixing flow regulating valve (403) is connected to a water supply valve (404). One side of the water supply valve (404) is connected to a water treatment instrument (401). One side of the water treatment instrument (401) is connected to an electric heater bypass valve (407). The electric heater bypass valve (407) is connected to the air source heat pump assembly (100). Both sides of the electric heater bypass valve (407) are respectively connected to an electric heater water inlet valve (405) and an electric heater water outlet valve (406). An electric heater (402) is connected between the electric heater water inlet valve (405) and the electric heater water outlet valve (406).

2. The deep-layer geothermal energy constant temperature method thermal property testing equipment according to claim 1 is characterized in that The air source heat pump assembly (100) includes an air source heat pump unit (101), the input end and the output end of the air source heat pump unit (101) are respectively connected to a heat pump unit water inlet valve (102) and a heat pump unit water outlet valve (103), a heat pump unit bypass valve (104) is connected between the heat pump unit water inlet valve (102) and the heat pump unit water outlet valve (103), and a first remote temperature meter (101) is connected to one side of the heat pump unit bypass valve (104). 05), one side of the first remote temperature gauge (105) is connected to a first remote pressure gauge (106), the first remote pressure gauge (106) is connected to the electric heater bypass valve (407), the other side of the heat pump unit bypass valve (104) is connected to a second remote temperature gauge (107), one side of the second remote temperature gauge (107) is connected to a second remote pressure gauge (108), the second remote pressure gauge (108) is connected to the pump assembly (200).

3. The deep-layer geothermal energy constant temperature method thermal property testing equipment according to claim 1 is characterized in that The pump assembly (200) includes a first circulating water pump (201) and a second circulating water pump (202), wherein the first circulating water pump (201) and the second circulating water pump (202) are connected in parallel, and water pump expansion joints (206) are connected to both sides of the first circulating water pump (201) and the second circulating water pump (202), and one side of the water pump expansion joint (206) is connected to a first local pressure gauge (207) and a drain valve (205), and one side of the first local pressure gauge (207) and the drain valve (205) is connected to a check valve (208) and a decontamination valve group (204), and one side of the check valve (208) and the decontamination valve group (204) is connected to a water pump shut-off valve (203), and a second local pressure gauge (209) is connected in series between the water pump shut-off valve (203) near the side of the check valve (208).

4. The medium-deep geothermal energy constant temperature method thermal property testing equipment according to claim 3 is characterized in that The geothermal data measurement component (300) includes a geothermal well (302), a heat exchanger (303) is fixedly installed in the geothermal well (302), the input end of the heat exchanger (303) is connected to a heat exchanger inlet valve (301), the heat exchanger inlet valve (301) is connected to a second local pressure gauge (209), a heat exchanger pipeline remote pressure gauge (306) and a heat exchanger pipeline remote temperature gauge (305) are connected between the heat exchanger inlet valve (301) and the second local pressure gauge (209), the heat exchanger The output end of the heat exchanger (303) is connected to a heat exchanger outlet valve (304), one side of the heat exchanger outlet valve (304) is connected to a decontamination valve group (204), one side of the decontamination valve group (204) is connected to a heat exchanger pipeline remote pressure gauge (306), one side of the heat exchanger pipeline remote pressure gauge (306) is connected to a heat exchanger pipeline remote temperature gauge (305), one side of the heat exchanger pipeline remote temperature gauge (305) is connected to a flow meter (307), and the flow meter (307) is connected to the flow dividing and mixing regulating valve (403).

5. A medium-deep geothermal energy constant temperature method thermal property testing equipment according to any one of claims 3 or 4, characterized in that The decontamination valve group (204) includes a Y-type filter, and the front and rear sides of the Y-type filter are respectively connected to filter pressure gauges.

6. The medium-deep geothermal energy constant temperature method thermal property testing equipment according to claim 3 is characterized in that The first circulating water pump (201) and the second circulating water pump (202) have specifications of 15m³ / h and 10m³ / h respectively, and the first circulating water pump (201) and the second circulating water pump (202) are made of stainless steel.

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