System for increasing energy supply by combining deep water type terrestrial heat with anti-corrosion water energy storage device

Abstract

The invention belongs to the technical field of heat supply, and relates to a system for increasing the supply energy of a deep water type geothermal combined anti-corrosion water energy storage device, which comprises a geothermal well, a first heat exchanger, a recharge well and a first heat supply pipe network which are connected in sequence, the energy storage unit comprises a heat storage tank; the auxiliary heat supply unit comprises a second heat exchanger, a water source heat pump and a second heat supply pipe network. The heat storage tank is additionally arranged, so that peak clipping and valley filling type flexible energy storage of geothermal water is achieved, a double-path heat supply structure of first-stage heat exchange direct supply and second-stage water source heat pump step temperature rising is constructed, a geothermal well can still keep stable water taking in the design flow in the low-load period, high-grade heat energy is stored and reused in a graded mode, and the energy utilization rate of the geothermal well is increased. The energy utilization efficiency of the system in the whole life cycle is improved, the economical advantage of the geothermal system compared with traditional energy supply equipment is enhanced, meanwhile, the application range of the system is widened, and large-scale application of the system in small and medium-sized public buildings and newly-built communities is powerfully promoted.

Description

Technical Field

[0001] This invention belongs to the field of heating technology and relates to a system for increasing energy supply by combining deep water geothermal energy with anti-corrosion water storage device. Background Technology

[0002] Deep water geothermal heating and cooling systems, as an important form of renewable energy utilization, have been widely applied in building energy-saving scenarios such as centralized heating in northern regions, district cooling in southern regions, and independent temperature and humidity control. A typical configuration includes geothermal extraction wells, heat exchange stations, terminal distribution networks, and user-side air conditioning / heating equipment. Heat transfer between geothermal water and the secondary working fluid (water) is achieved through plate or shell-and-tube heat exchangers. System design is usually based on the building's maximum hourly heat / cooling load, working backwards to deduce the required geothermal water flow rate, and accordingly determine the geothermal well water intake, heat exchange area, and pump head.

[0003] However, in actual operation, due to factors such as climate fluctuations, changes in building occupancy rates, and dynamic load characteristics, the actual hourly load of buildings has long been in a low range, resulting in the actual water extraction from geothermal wells being far lower than the design value. This phenomenon means that a large amount of high-grade geothermal energy cannot be effectively extracted and utilized, which not only significantly reduces the energy utilization efficiency of the system throughout its entire life cycle, but also directly weakens the economic advantages of geothermal systems compared to traditional energy supply equipment such as gas boilers and air source heat pumps, thus restricting its large-scale promotion and application in small and medium-sized public buildings and new communities. Summary of the Invention

[0004] The purpose of this invention is to provide a system that combines deep-water geothermal energy with corrosion-resistant water storage device to increase energy supply. This system can effectively store underutilized high-grade geothermal energy, adjust the matching degree between geothermal water intake and building dynamic load, and improve the system's energy utilization efficiency and economy.

[0005] To achieve the above objectives, the technical solution provided by the present invention is as follows: A system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device includes a geothermal well, a first heat exchanger, and a reinjection well connected in sequence. The first heat exchanger is connected to a first heating network. The system also includes: The energy storage unit includes a thermal storage tank, the inlet of which is connected to the outlet of a geothermal well, and the outlet of which is connected to the first inlet of a first heat exchanger. The thermal storage tank is used to store geothermal water from the geothermal well. The auxiliary heating unit includes a second heat exchanger, a water source heat pump, and a second heating network. The first inlet of the second heat exchanger is connected to the first outlet of the first heat exchanger, and the first outlet of the second heat exchanger is connected to the inlet of the reinjection well. The first inlet of the water source heat pump is connected to the second outlet of the second heat exchanger, and the first outlet of the water source heat pump is connected to the second inlet of the second heat exchanger. The second outlet of the water source heat pump is connected to the inlet of the second heating network, and the second inlet of the water source heat pump is connected to the outlet of the second heating network. Geothermal water in the heat storage tank is stored in the heat storage tank and enters the first heat exchanger and the second heat exchanger in sequence during heating, working with the first heating network and the water source heat pump and the second heating network to provide secondary heating.

[0006] The invention is further characterized by: A buffer tank is installed between the first outlet of the second heat exchanger and the inlet of the reinjection well. The inlet of the buffer tank is connected to the first outlet of the second heat exchanger, and the outlet of the buffer tank is connected to the inlet of the reinjection well.

[0007] The first heat exchanger, the second heat exchanger, and the heat storage tank are all corrosion-resistant structures.

[0008] The temperature difference between the outlet water of the geothermal well and the return water of the reinjection well is 35℃~45℃.

[0009] The temperature difference between the outlet water of the geothermal well and the return water temperature of the reinjection well is 40℃.

[0010] The water supply temperature of both the first and second heating networks is 40℃~50℃.

[0011] The water supply temperature of both the first and second heating networks is 45℃.

[0012] The return water temperature of both the first and second heating networks is 30℃~40℃.

[0013] The return water temperature of both the first and second heating networks is 35℃.

[0014] The deep-water geothermal combined with corrosion-resistant water storage device of the present invention, which increases energy supply, has the following advantages: This invention achieves flexible energy storage of geothermal water by adding a thermal storage tank, and constructs a dual-path heating architecture of "first-level heat exchange direct supply + second-level water source heat pump cascade heating". This allows the geothermal well to maintain a stable water intake at the design flow rate during low-load periods, and high-grade heat energy to be stored and reused in stages. This improves the energy utilization efficiency of the system throughout its entire life cycle, strengthens the economic advantages of the geothermal system compared with traditional energy supply equipment, and expands the applicable scenarios of the system, which can effectively promote its large-scale application in small and medium-sized public buildings and new communities. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0016] Figure label: 1. Geothermal well, 2. Heat storage tank, 3. First heat exchanger, 4. First heating network, 5. Second heating network, 6. Water source heat pump, 7. Second heat exchanger, 8. Buffer tank, 9. Recharge well. Detailed Implementation

[0017] The technical solutions of the present invention will now be described clearly and in detail with reference to the accompanying drawings. In the description of the embodiments of the present invention, unless otherwise stated, " / " indicates "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Furthermore, in the description of the embodiments of the present invention, "multiple" refers to two or more. The terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0018] like Figure 1As shown, this invention provides a system for increasing energy supply by combining deep-water geothermal energy with a corrosion-resistant water storage device. It includes a geothermal well 1, a first heat exchanger 3, and a reinjection well 9 connected in sequence. The first heat exchanger 3 is connected to a first heating network 4. The system also includes an energy storage unit and an auxiliary heating unit. The energy storage unit includes a heat storage tank 2, whose inlet is connected to the outlet of the geothermal well 1, and whose outlet is connected to the first inlet of the first heat exchanger 3. The heat storage tank 2 is used to store geothermal water from the geothermal well 1. The auxiliary heating unit includes a second heat exchanger 7, a water source heat pump 6, and a second heating network 5. The first inlet of the second heat exchanger 7 is connected to the first... The first outlet of heat exchanger 3 is connected to the first outlet of the second heat exchanger 7 and the inlet of the reinjection well 9. The first inlet of the water source heat pump 6 is connected to the second outlet of the second heat exchanger 7, the first outlet of the water source heat pump 6 is connected to the second inlet of the second heat exchanger 7, the second outlet of the water source heat pump 6 is connected to the inlet of the second heating network 5, and the second inlet of the water source heat pump 6 is connected to the outlet of the second heating network 5. The geothermal water in the heat storage tank 2 is stored in the heat storage tank 2 and enters the first heat exchanger 3 and the second heat exchanger 7 in sequence during heating, so as to cooperate with the first heating network 4 and the water source heat pump 6 and the second heating network 5 for secondary heating. This invention achieves flexible energy storage of geothermal water by adding a heat storage tank 2, and constructs a dual-path heating architecture of "first-level heat exchange direct supply + second-level water source heat pump cascade heating". This allows the geothermal well to maintain a stable water intake at the design flow rate during low-load periods, and high-grade heat energy to be stored and reused in stages. This improves the energy utilization efficiency of the system throughout its entire life cycle, strengthens the economic advantages of the geothermal system compared with traditional energy supply equipment, and expands the applicable scenarios of the system, which can effectively promote its large-scale application in small and medium-sized public buildings and new communities.

[0019] like Figure 1 As shown, a buffer tank 8 is installed between the first outlet of the second heat exchanger 7 and the inlet of the reinjection well 9. The inlet of the buffer tank 8 is connected to the first outlet of the second heat exchanger 7, and the outlet of the buffer tank 8 is connected to the inlet of the reinjection well 9. The buffer tank 8 installed between the second heat exchanger 7 and the reinjection well 9 can stabilize the water pressure, flow and temperature of the geothermal tailwater, avoid the impact of flow and pressure fluctuations on the reinjection well 9, ensure the smooth and continuous reinjection process, and improve the stability of system operation and the safety and reliability of reinjection operations.

[0020] like Figure 1As shown, the inlet of the heat storage tank 2 is connected to the outlet of the geothermal well 1 via a first circulation pump; the outlet of the heat storage tank 2 is connected to the first inlet of the first heat exchanger 3 via a second circulation pump; the first outlet of the first heat exchanger 3 is connected to the inlet of the first heating network 4 via a third circulation pump; the first outlet of the second heat exchanger 7 is connected to the inlet of the buffer tank 8 via a fourth circulation pump; the outlet of the buffer tank 8 is connected to the inlet of the reinjection well 9 via a fifth circulation pump; and the second outlet of the water source heat pump 6 is connected to the inlet of the second heating network 5 via a sixth circulation pump.

[0021] Among them, the first heat exchanger 3, the second heat exchanger 7 and the heat storage tank 2 are all corrosion-resistant structures. Adopting corrosion-resistant structures for the first heat exchanger 3, the second heat exchanger 7 and the heat storage tank 2 can effectively resist the erosion of corrosive media in geothermal water, extend the service life of core equipment, reduce operation and maintenance and replacement costs, and at the same time ensure the long-term operation of the system's airtightness, heat exchange efficiency and overall stability, and avoid affecting the geothermal utilization and reinjection process due to equipment corrosion and leakage.

[0022] like Figure 1 As shown, the temperature difference between the outlet water of geothermal well 1 and the return water of reinjection well 9 is 35℃~45℃, and the preferred temperature difference is 40℃. Setting the temperature difference between the outlet water of geothermal well 1 and the return water of reinjection well 9 at 35℃~45℃, preferably 40℃, can ensure the full utilization of geothermal water cascade heat exchange and maximize the extraction of geothermal energy, while also taking into account the adaptability and operational stability of the system heat exchange equipment. It can also improve the utilization rate of geothermal energy per unit volume of water, reduce the amount of water extracted from geothermal wells and the energy consumption of system transmission and distribution, and enhance the overall energy efficiency and economy of the system.

[0023] like Figure 1 As shown, the water supply temperature of the first heating network 4 and the second heating network 5 are both 40℃~50℃, and the preferred water supply temperature of both is 45℃. Setting the water supply temperature of the first heating network 4 and the second heating network 5 to 40℃~50℃, with 45℃ being preferred, can not only match the conventional applicable temperature range of building terminal heating and air conditioning equipment and ensure comfortable heating effect on the user side, but also efficiently adapt to the geothermal water cascade heat exchange process, maximizing the cascade utilization of heat energy, while taking into account the safety of network operation, transmission energy consumption and overall system heat exchange efficiency, thus improving heating stability and economy.

[0024] like Figure 1As shown, the return water temperature of the first heating network 4 and the return water temperature of the second heating network 5 are both 30℃~40℃, and the preferred return water temperature of both is 35℃. Setting the return water temperature of the first heating network 4 and the second heating network 5 at 30℃~40℃, preferably 35℃, can form a reasonable and stable supply and return water temperature difference with the supply water temperature of 40℃~50℃, preferably 45℃, ensuring the heat dissipation / heat exchange effect at the terminal and indoor thermal comfort. It can also adapt to the temperature matching characteristics of the cascade heat exchange system, improve the extraction and utilization rate of geothermal heat energy and the system operation energy efficiency, and reduce the energy consumption of network circulation and transportation, thus taking into account both heating quality and system economy.

[0025] Working principle: When in use, the 50℃ geothermal water extracted from the geothermal well 1 is first stored in the heat storage tank 2. According to the heat load of the original heating users, it is transported to the first heat exchanger 3 by the variable frequency water pump. After heat exchange, the temperature drops to 40℃. The supply and return water temperatures of the original first heating network 4 remain unchanged at 45℃ and 35℃, respectively, to ensure that the indoor thermal comfort meets the requirements and realize the first-level heating of geothermal water.

[0026] After heat exchange, the geothermal water, whose temperature drops to 40°C at the first heat exchanger 3, exchanges heat with the evaporator side of the water source heat pump 6 through the second heat exchanger 7, and its temperature drops to 10°C before flowing into the buffer tank 8. Through heat exchange with the second heat exchanger 7, the water temperature on the evaporator side of the water source heat pump 6 increases from 7°C to 15°C, while the water temperature on the condenser side of the water source heat pump 6 increases from 35°C to 45°C, supplying the indoor second heating network 5. This also ensures the indoor thermal comfort requirements and realizes the secondary heating of geothermal water.

[0027] Finally, the geothermal return water in buffer tank 8 is returned to reinjection well 9 according to the designed flow rate.

[0028] The deep-water geothermal combined with corrosion-resistant water storage device of the present invention has the following other advantages in increasing energy supply: First, without increasing the power consumption of the main pipeline network and circulating pump, and without changing the original heating parameters, this invention combines the use of a corrosion-resistant thermal storage tank and a water source heat pump to utilize the supply and return water of the traditional geothermal water reinjection heating system in two stages according to temperature, and increases the heating area by peak shaving and valley filling through the corrosion-resistant thermal storage tank.

[0029] Secondly, this invention adds a corrosion-resistant heat storage tank and a buffer tank to the existing geothermal water reinjection system. The high-temperature geothermal water extracted from the ground is stored in the heat storage tank. The amount of geothermal water entering the heat storage tank is dynamically adjusted according to the user's heating load. The heating area is increased without increasing the number of geothermal wells. After heat exchange, the geothermal water first enters the buffer tank to ensure a stable reinjection flow rate and avoid fluctuations in the amount of geothermal water reinjected due to changes in the user's heating load.

[0030] It is understood that this invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this invention are within the protection scope of this invention.

Claims

1. A system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device, comprising a geothermal well, a first heat exchanger, and a reinjection well connected in sequence, wherein the first heat exchanger is connected to a first heating pipeline network, characterized in that, Also includes: An energy storage unit includes a thermal storage tank, the inlet of which is connected to the outlet of a geothermal well, and the outlet of which is connected to the first inlet of a first heat exchanger. The thermal storage tank is used to store geothermal water from the geothermal well. The auxiliary heating unit includes a second heat exchanger, a water source heat pump, and a second heating network. The first inlet of the second heat exchanger is connected to the first outlet of the first heat exchanger, and the first outlet of the second heat exchanger is connected to the inlet of the reinjection well. The first inlet of the water source heat pump is connected to the second outlet of the second heat exchanger, and the first outlet of the water source heat pump is connected to the second inlet of the second heat exchanger. The second outlet of the water source heat pump is connected to the inlet of the second heating network, and the second inlet of the water source heat pump is connected to the outlet of the second heating network. Geothermal water in the heat storage tank is stored in the heat storage tank and enters the first heat exchanger and the second heat exchanger sequentially during heating to provide secondary heating in conjunction with the first heating network, the water source heat pump, and the second heating network.

2. The system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 1, characterized in that, A buffer tank is provided between the first outlet of the second heat exchanger and the inlet of the reinjection well. The inlet of the buffer tank is connected to the first outlet of the second heat exchanger, and the outlet of the buffer tank is connected to the inlet of the reinjection well.

3. The system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 1, characterized in that, The first heat exchanger, the second heat exchanger, and the heat storage tank are all corrosion-resistant structures.

4. The system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 1, characterized in that, The temperature difference between the outlet water temperature of the geothermal well and the return water temperature of the reinjection well is 35℃~45℃.

5. The system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 4, characterized in that, The temperature difference between the outlet water temperature of the geothermal well and the return water temperature of the reinjection well is 40℃.

6. The system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 1, characterized in that, The water supply temperature of both the first and second heating networks is 40℃~50℃.

7. A system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 6, characterized in that, The water supply temperature of both the first and second heating networks is 45℃.

8. A system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 1, characterized in that, The return water temperature of both the first and second heating pipe networks is 30℃~40℃.

9. A system for increasing energy supply using a deep-water geothermal combined with corrosion-resistant water storage device according to claim 8, characterized in that, The return water temperature of both the first and second heating pipe networks is 35℃.

Images