A geotechnical heat compensation device and control method for enhancing absorption of air latent heat

Abstract

The application provides a rock-soil heat compensation device and control method for strengthening air latent heat absorption, and belongs to the technical field of underground rock-soil heat compensation of ground source heat pumps. The device comprises a buried pipe system and a heat compensation tower. A dust removal section and a water storage section are sequentially arranged in the tower along an air inlet direction. A two-section heat exchange section (pre-cooling section + condensation section), a spraying system and an air outlet section are arranged along an air flow upward direction. Low-temperature circulating water is preferentially introduced into the condensation section and then flows through the pre-cooling section, so that cold energy cascade utilization is realized. The control method takes a condensation driving force as a core parameter, adopts a temperature difference (Delta t) greater than or equal to 1 DEG C as the only starting criterion, calculates a COP in real time after the system is started, and executes energy efficiency protection in combination with peak-valley electricity prices in different time periods. The frequency of a water pump and an air exhaust fan is adaptively adjusted to optimize the air-water ratio. The application makes the condensation section be in a deep dew separation condition through a pre-cooling and moisture extraction mechanism, the proportion of latent heat recovery is high, air latent heat can be efficiently stored in underground rock-soil, and a new way is provided for solving the underground heat imbalance problem of a ground source heat pump project in the north.

Description

Technical Field

[0001] This invention belongs to the field of underground rock and soil heat compensation technology for ground source heat pumps, specifically relating to a rock and soil heat compensation device and control method for enhancing the absorption of latent heat from the air. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Ground source heat pumps rely on the heat stored in underground soil and rock to provide heating for buildings in winter. In northern regions where winter heating loads far exceed summer heat replenishment, buildings continuously extract large amounts of heat from the underground soil and rock. This prevents the soil and rock from fully warming up, leading to an imbalance in heat supply and demand throughout the year, and a continuous decline in underground soil temperature year after year. Once the soil temperature drops to a critical value, the temperature difference between the buried pipes and the soil and rock shrinks significantly, causing a sharp drop in the heat absorption efficiency of the ground source heat pump unit and a significant increase in heating power consumption. In severe cases, the unit may fail to absorb enough heat and cannot provide normal heating. This problem is particularly acute in many early single-function ground source heat pump projects in the region that only provided winter heating and lacked active summer heat replenishment facilities. Existing remedial methods often involve direct electric heating to replenish the soil and rock, which is energy-intensive, expensive to operate, and extremely uneconomical.

[0004] Existing open-type energy tower equipment used for geothermal heat exchange directly contacts air with circulating water for heat exchange. Dust and silt carried by outdoor air will continuously mix into the circulating water, and water impurities will enter the underground U-shaped buried heat exchanger through the pipeline. Long-term operation will easily cause scaling on the pipe wall and pipeline blockage. Furthermore, closed-type energy towers on the market isolate air from underground circulating water through an intermediate heat exchange medium. Although this can solve the problem of pipe dirt blockage, secondary heat exchange will produce additional temperature difference loss. The temperature of the spray water is 2-3°C higher than that of the underground circulating water. The heat exchange range between the low-temperature circulating water and the air is narrowed, and water vapor in the air is difficult to condense fully. The ability to capture the latent heat of the air is greatly reduced, and the overall heat exchange efficiency is low. It is impossible to efficiently utilize the latent heat of the air to complete the heat supply of underground geothermal heat. Summary of the Invention

[0005] To overcome the shortcomings of the existing technology, this invention provides a geothermal heat compensation device and control method for enhancing the absorption of latent heat from the air. The device includes a buried pipe system and a heat compensation tower. Inside the tower, a dust removal section and a water storage section are sequentially arranged along the air intake direction. Along the upward airflow direction, a two-stage heat exchange section (pre-cooling section + condensing section), a spray system, and an exhaust section are arranged. Low-temperature circulating water preferentially flows into the condensing section before passing through the pre-cooling section, achieving cascaded utilization of cooling capacity. The control method uses the condensation driving force as the core parameter and Δt ≥ 1℃ as the sole start-up criterion. After system startup, the COP is calculated in real time, and energy efficiency protection is implemented in time-of-days based on peak and off-peak electricity prices. The frequency of the water pump and exhaust fan is adaptively adjusted to optimize the air-to-water ratio. This invention, through a pre-cooling and humidification mechanism, keeps the condensing section in a deep dehumidification state throughout, resulting in a high latent heat recovery rate. It can efficiently store latent heat from the air in the underground geothermal environment, providing a new approach to solving the problem of underground heat imbalance in northern ground source heat pump projects.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a geothermal heat compensation device for enhancing the absorption of latent heat of air, comprising a buried pipe system and a heat compensation system. The heat compensation system includes a heat compensation tower with air inlets symmetrically arranged on both sides of its bottom. Along the horizontal airflow direction, a dust removal section and a water storage section are sequentially arranged inside the heat compensation tower from the outside to the inside. The water storage section has a water tank. Along the vertical airflow direction, a heat exchange section, a spray system, and an exhaust section are sequentially arranged above the water tank. The buried pipe system includes a heat exchanger buried inside the geothermal soil. Both ends of the heat exchanger are connected to the water tank and the spray system via circulation pipes, forming a circulating water path. Multiple interconnected baffles are arranged vertically parallel inside the heat exchange section, and the baffle cavities are filled with heat exchange packing. The heat exchange section is divided into a pre-cooling section and a condensation section from bottom to top. A horizontally arranged air distribution baffle is mounted at the bottom of the pre-cooling section.

[0007] Furthermore, the heat compensation tower is a vertical rectangular tower body, which is divided along the height direction into a bottom horizontal air inlet chamber, a middle vertical heat exchange chamber, and an upper exhaust section. The dust removal section and water storage section are arranged in the bottom horizontal air inlet chamber, the heat exchange section is located in the middle vertical heat exchange chamber, and the spray system and exhaust section are located in the upper exhaust section. The above functional sections are arranged along the internal space of the tower.

[0008] Furthermore, the dust removal section includes a filter screen, a dust removal spray system, and an overflow pipe. The filter screen is vertically arranged at the bottom of the heat compensation tower's air duct. The dust removal spray system consists of dust removal nozzles, a submersible pump, and a sewage discharge pipe. A water collection tank is provided at the bottom of the heat compensation tower, corresponding to the dust removal section. The submersible pump is submerged and installed in the water collection tank. The outlet of the submersible pump is connected to the dust removal nozzle. One end of the sewage discharge pipe is connected to the water collection tank, and the other end is connected to an external drainage channel. One end of the overflow pipe is connected to the overflow position at the top of the water collection tank, and the other end is connected to an external drainage channel.

[0009] Furthermore, the water storage tank is provided on both the left and right sides, and the water storage tank is located in the center of the horizontal air inlet at the bottom of the heat compensation tower. Both the dust removal section and the water storage section are equipped with automatic water replenishment valves, and the automatic water replenishment valves are connected to the control system via electrical signals.

[0010] Furthermore, the exhaust section is equipped with an air guide plate, the exhaust outlet is located on the side wall of the upper part of the heat compensation tower, and an exhaust fan is installed at the outlet.

[0011] Furthermore, a windbreak wall is provided on the outside of the heat compensation tower, and ventilation openings are reserved on the windbreak wall, which are connected to the air outlet of the exhaust section.

[0012] Furthermore, the spray system includes multiple sets of spray nozzles evenly arranged at the top of the heat exchange section. The heat exchanger is a U-shaped heat exchanger, and a circulating water pump is installed on the circulation pipeline connected to the water storage tank. The circulating water pump is electrically connected to the control system. The circulating water pump delivers low-temperature circulating water to the spray system for spraying from top to bottom, allowing for full contact and heat exchange with the upward air.

[0013] Furthermore, the dust removal section is also equipped with a water baffle plate, which is arranged between the filter screen and the air inlet, and the height of the water baffle plate is higher than that of the overflow pipe. The wind distribution baffle plate is arranged horizontally above the water storage tank, and several ventilation holes are evenly opened on the wind distribution baffle plate.

[0014] The control method for the above-mentioned gas-water heat exchanger soil heat compensation device includes the following steps: S1: System initialization, self-test of each sensor and actuator, and reading the current time to determine the electricity price period; S2: Real-time acquisition of parameters such as inlet dry bulb temperature, relative humidity, supply and return water temperature, flow rate, liquid level, and power; S3: Calculate the air dew point temperature based on the inlet dry-bulb temperature and relative humidity, and obtain the condensation driving force. ; S4: Determine the COP operation protection threshold based on the current electricity price period; S5: Determine if the start-up conditions are met. If Δt≥1℃ and the liquid level is normal, start the system and maintain the minimum continuous running time; otherwise, return to S2 to continue the detection. S6: Based on the interval where Δt is located, automatically adjust the frequency of the water pump and fan according to the rules to optimize the air-water ratio; When Δt < 2℃, the frequency of the circulating water pump is automatically increased by 10% to 20%, the spray flow rate is increased, and the frequency of the exhaust fan is reduced by 10% to 15%. When 2℃≤Δt≤5℃, both the water pump and the fan maintain rated frequency operation to balance heat exchange efficiency and air volume. When Δt>5℃, dynamically increase the exhaust fan frequency by 10% to 25% to increase the air handling capacity, while appropriately reducing the water pump frequency by 5% to 10%.

[0015] S7: Monitors the system's operating status in real time, executes logic such as liquid level protection, energy efficiency protection, and antifreeze protection, and calculates the system's COP in real time; S8: Determine if the shutdown conditions are met. Shut down if any of the following conditions are met: (a) (a) <1℃; (b) COP is below the current time period threshold for 10 consecutive minutes; (c) Liquid level failure cannot be recovered; after shutdown, maintain the minimum downtime, otherwise return to S2 to continue the cycle control.

[0016] Furthermore, the system COP calculation formula in step S7 is as follows: ; In the formula, c is the specific heat capacity of water; ρ is the density of water; and G is the circulating water flow rate. The return water temperature; For water supply temperature, and spray water supply temperature For the same temperature value; For water pump power, For fan power, Power for auxiliary equipment.

[0017] Based on one or more of the above technical solutions, the present invention has the following beneficial effects: Firstly, the heat exchange section is divided into a two-stage structure: a pre-cooling section and a condensing section. The pre-cooling section first absorbs sensible heat from the air to increase the relative humidity, and then the low-temperature circulating water in the condensing section captures the latent heat released by the condensation of water vapor. This layered heat exchange mode fully taps into the latent heat resources in the air, significantly increases the total amount of heat absorbed from the air, strengthens the heat replenishment capacity for underground soil and rock, and makes up for the low latent heat utilization rate of closed energy towers. Furthermore, heat exchangers are installed underground, which can efficiently store the heat absorbed by the tower into the underground soil, balance the heat loss of the soil and rock caused by the ground source heat pump in winter, effectively inhibit the annual cooling of the underground soil and rock, and ensure that the ground source heat pump maintains high heating efficiency throughout the year.

[0018] Low-temperature cooling capacity utilization mechanism: Low-temperature chilled water is given priority to the condensation section, so that the water temperature of the entire packing section is below the dew point temperature, and the entire section is in a high-efficiency condensation condition; the tail water after heating then enters the pre-cooling section to recover sensible heat, realizing the cascade utilization of cooling capacity quality, avoiding the problem in traditional single-stage towers where low-temperature chilled water is directly heated by dry hot air, resulting in excessively high water temperature in the condensation section and inability to dehumidify.

[0019] Pre-cooling and humidification enhance latent heat density: The pre-cooling section first cools the air to a saturated state with equal humidity, eliminating the sensible heat load of the air. After the air enters the condensing section, it immediately enters the deep condensation condition without the need for additional sensible heat cooling stroke, and the latent heat recovery per unit packing height is greatly improved.

[0020] Secondly, the heat compensation tower adopts a vertical rectangular layered cavity layout, with clear functional zones for dust removal, water storage, heat exchange and exhaust. The air distribution baffle can evenly distribute the airflow, eliminate local airflow deviation and uneven heat exchange, and improve the overall heat exchange uniformity inside the tower.

[0021] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0023] Figure 1 This is a schematic diagram of the overall structure of the gas-water heat exchanger for soil and rock heat compensation device of the present invention. Figure 2 This is a front sectional view of the gas-water heat exchanger for soil and rock heat compensation device of the present invention. Figure 3 This is a side sectional view of the gas-water heat exchanger for soil and rock heat compensation device of the present invention; Figure 4 This is a top view of the gas-water heat exchanger for soil and rock heat compensation device of the present invention; Figure 5 This is a structural diagram of the control system of the gas-water heat exchanger for soil and rock heat compensation device of the present invention; Figure 6 This is a flowchart of the control method for the gas-water heat exchanger soil heat compensation device of the present invention; The components include: 1. Dust removal section; 2. Water storage section; 3. Heat exchange section; 4. Exhaust section; 5. Spray system; 6. Windbreak wall; 7. Circulating water pump; 8. Underground pipe system; 81. Heat exchanger; 82. Soil and rock; 9. Control system; 91. PLC controller; 92. Temperature sensor; 93. Humidity sensor; 95. Power meter; 94. Heat meter; 42. Fan; 10. Baffle; 11. Sewage pipe; 12. 13. Filter screen; 14. Water baffle; 15. Submersible pump; 16. Dust removal nozzle; 17. Drain valve; 18. Overflow pipe; 19. Heat compensation tower; 20. Air inlet; 21. Air outlet; 22. Water storage tank; 23. Air distribution baffle; 34. Automatic water supply valve; 35. Precooling section; 36. Condensation section; 37. Packing material; 48. Air guide plate; 49. Exhaust fan; 50. Spray nozzle; 51. Water collection tank. Detailed Implementation

[0024] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention. Unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0026] like Figure 1 - Figure 5 As shown, this embodiment provides a geothermal heat compensation device for enhancing the absorption of latent heat from the air. The main body of the heat compensation device includes a vertical rectangular heat compensation tower 18, a windbreak wall 6 set on the exhaust side of the heat compensation tower, a U-shaped buried heat exchanger 81 buried inside the underground geothermal 82, and a matching PLC automatic control system. The entire set of equipment is equipped with a complete air and water circuit structure, realizing the step-by-step recovery of sensible heat and latent heat from the air, and continuously replenishing heat to the underground geothermal soil, balancing the problem of low underground temperature caused by long-term winter heat extraction by the ground source heat pump.

[0027] Specifically, the heat compensation tower is naturally divided into a bottom horizontal air inlet chamber, a middle vertical heat exchange chamber, and an upper exhaust section 4 along its height. Outdoor air flows horizontally into the bottom horizontal air inlet chamber through the symmetrical air inlets on both sides of the bottom of the tower. Along the horizontal air inlet direction, the horizontal air inlet chamber inside the heat compensation tower is provided with a dust removal section and a water storage section from the outside to the inside. The water storage section 2 is located in the middle of the entire bottom horizontal air inlet chamber, and the dust removal section 1 is symmetrically arranged on the left and right sides of the water storage section.

[0028] The dust removal section 1 includes a filter screen 12, a dust removal spray system, and an overflow pipe 17. The filter screen is vertically arranged at the air inlet 19 of the horizontal air inlet chamber at the bottom of the heat compensation tower. The filter screen can perform preliminary filtration of impurities in the air. A baffle plate 13 is installed behind the filter screen. The baffle plate is used to prevent the water mist and splashing water droplets formed by the downward spray of the dust removal nozzle 15 from flowing backward into the rear water storage section 2 and the middle vertical heat exchange chamber with the upward airflow. This prevents a large amount of spray water from being carried away by the airflow, causing continuous loss of circulating water volume. At the same time, it prevents the water mist from carrying dust into the rear packing and causing blockage.

[0029] The dust removal spray system consists of dust removal nozzles 15, water collection tanks 52, submersible pumps 14, and drain pipes 11. Water collection tanks 52 are symmetrically arranged on both sides of the horizontal air inlet chamber at the bottom of the heat compensation tower. The submersible pumps 14 are completely submerged inside the water collection tanks. The dust removal nozzles are positioned above the water collection tanks and behind the baffle plates. A three-way branch pipe is installed at the outlet of the submersible pump; one branch connects upwards to the dust removal nozzles, continuously supplying them with spray water. The dust removal nozzles continuously spray water onto the pre-treated air to wash it. Dust in the air is trapped and washed into the water collection tank. The air is then subjected to secondary dust removal through spray water, achieving secondary air purification. Another line connects to the sewage discharge pipeline, which is located at the bottom of the water collection tank. The sewage discharge pipeline is equipped with an electrically controlled sewage discharge valve controlled by the PLC controller 91 of the control system 9. When the amount of sediment in the water collection tank reaches the set value, the PLC controller will open the sewage discharge valve, and the submersible pump will pressurize and discharge the high-mud-content sewage to the external drainage network.

[0030] An overflow pipe 17 is connected to the top of the water collection tank. The height of the overflow pipe must be lower than that of the baffle plate. This allows the water in the collection tank to be discharged promptly when it reaches the height of the overflow pipe, automatically draining water when the water level exceeds the limit to maintain a safe liquid level in the tank. Furthermore, the height of the overflow pipe must be strictly lower than that of the baffle plate; if it is higher, the water in the collection tank will flow towards the baffle plate, and the overflowing water will then flow over the baffle plate. In this embodiment, the submersible pump is equipped with a liquid level-linked start / stop function. When the water level in the collection tank reaches the working level, the spray water circuit is automatically activated; when the water level is too low, the pump stops to prevent dry burning. This ensures continuous circulation of the dust removal washing water and periodically removes deposited sludge, preventing the accumulation of sludge and sand that could clog the air ducts and pipes, thus guaranteeing the long-term stable operation of the dust removal section.

[0031] Water storage tanks 21 are arranged inside the water collection tanks on the left and right sides. Above the water storage tanks, air distribution baffles 22 with several ventilation holes are laid horizontally. The air purified by dust removal can be evenly transported upward through the ventilation holes of the air distribution baffles. Water supply pipes with automatic water supply valves 23 are connected to the water storage tanks and the water collection tanks on both sides. The automatic water supply valves 23 are connected to the controller by electrical signals. When the liquid level in the corresponding tank is insufficient, water can be automatically replenished to ensure the stability of the circulating water volume of the system.

[0032] Airflow enters the central vertical heat exchange chamber from the air distribution baffle. A number of interconnected baffles 10 are evenly arranged horizontally inside the heat exchange chamber, which is divided into a lower pre-cooling section 31 and an upper condensing section 32. The baffle chamber is filled with heat exchange packing material 321. The spray system includes multiple sets of spray nozzles 51 evenly arranged at the top of the heat exchange section. Water is continuously sprayed downwards through the multiple sets of spray nozzles 51. After heat exchange, the airflow flows upwards into the upper exhaust section. The exhaust section is equipped with air guide plates 41 for regulating airflow. An air outlet 20 is opened on the upper side wall of the tower, and a variable frequency exhaust fan 42 is installed at the air outlet. This variable frequency exhaust fan is electrically connected to the control system and forces the low-temperature humid air after heat exchange to be discharged outwards through the variable frequency exhaust fan.

[0033] The height of the heat compensation tower exterior extends beyond the windbreak wall 6 at the air outlet. This windbreak wall has pre-installed ventilation interfaces to match the air outlet. The exhausted cold air diffuses downwards along the outside of the windbreak wall, preventing it from flowing back to the air inlet 19 at the bottom of the tower, thus avoiding a decrease in inlet air temperature and a reduction in the heat exchange temperature difference. The windbreak wall also prevents the low-temperature cold air from flowing back to the equipment inlet, stabilizing the base temperature of the air entering the heat compensation tower, ensuring a stable temperature difference required for air-water heat exchange, and preventing a continuous decrease in heat absorption efficiency due to short-circuiting of the return air.

[0034] Multiple sets of parallel U-shaped buried heat exchangers 81 are installed in the underground rock and soil. The two ends of the heat exchangers are connected to the water storage tank 21 and the spray system 5 through circulation pipelines to form a circulating water circuit. A circulating water pump 7 is installed on the circulation pipeline connecting the heat exchangers and the water storage tank. This circulating water pump is also connected to the control system electrical signal. The return water in the U-shaped buried heat exchangers is pressurized by the circulating water pump and then transported to the heat exchange section to complete the air-water heat exchange. The warm water, after absorbing the sensible heat and latent heat of the air, flows back to the water storage tank and then enters the underground U-shaped heat exchanger to release heat to the surrounding rock and soil, making up for the heat taken away from the ground by the ground source heat pump in winter and solving the problem of the underground rock and soil cooling down year by year.

[0035] The U-shaped heat exchanger is buried within the underground rock and soil to form the core of the buried heat exchange. The heated circulating water, after absorbing the sensible and latent heat of the air through the heat compensation tower, flows into the U-shaped pipe. The water flows into full contact with the surrounding underground rock and soil for heat exchange, continuously transferring and storing the heat carried by the water to the surrounding rock and soil. This compensates for the large amount of heat extracted from the ground during winter heating by the ground source heat pump, balancing the annual heat balance of the rock and soil and preventing the underground soil from cooling down year by year. After the heat is released and the water temperature drops, the circulating water flows back to the heat exchange section of the heat compensation tower to reabsorb heat from the air, thus forming a continuous circulating heat replenishment loop. Simultaneously, the U-shaped pipe has sufficient burial depth and a large heat exchange area with the rock and soil, ensuring sufficient heat exchange and stable storage of excess heat from the ambient air. This maintains the underground rock and soil within a suitable heat exchange temperature range for a long time, guaranteeing the efficient heating operation of the ground source heat pump throughout the year.

[0036] This embodiment involves sensible heat and latent heat, so we will first explain these two terms: Sensible heat absorption (pre-cooling section) refers to the heat carried by the air itself. The air temperature is higher than the sprayed water, and the heat is directly exchanged, causing the air to cool down while the water temperature rises. Only the air temperature is changed, and no condensation is produced. Latent heat absorption (condensation section) refers to the invisible water vapor in the air. When the water vapor turns into liquid water, it releases a large amount of stored heat (latent heat). The humidity of the pre-cooled air is close to saturation. When it encounters cold water at an even lower temperature, the water vapor condenses into water, and this released heat is carried away by the water.

[0037] The low-temperature circulating water flows from top to bottom through the packing material of the condensation section and the precooling section. The rising air first comes into full contact with the low-temperature spray water in the precooling section. The sensible heat of the air is absorbed by the water, and the relative humidity of the air increases significantly. The high-humidity airflow continues to rise into the condensation section, where it comes into full contact with the circulating water with the lowest temperature in the entire system. Water vapor in the air condenses when it encounters the cold packing material, and a large amount of latent heat of vaporization is released and absorbed by the circulating water, thus completing the efficient capture of latent heat of the air.

[0038] A simpler description is as follows: The low-temperature circulating water first flows through the lower pre-cooling section and comes into direct contact with the ambient-temperature rising air. The air's temperature is higher than that of the sprayed cold water, and the sensible heat carried by the air is directly transferred to the circulating water. After the air cools down, its ability to hold water vapor decreases, and its relative humidity increases rapidly. The humidified air continues to rise into the upper condensation section, where the circulating water temperature is the lowest in the entire system. The saturated water vapor in the air comes into contact with the low-temperature packing and liquefies and condenses. When the water molecules vaporize, all the latent heat stored is released and absorbed by the circulating water, thus completing the two-stage recovery of sensible and latent heat simultaneously. The warm water that has absorbed the heat from the air flows back to the storage tank and then enters the underground U-shaped heat exchanger to release heat to the surrounding soil and rock, making up for the heat taken away from the ground by the ground source heat pump in winter and solving the problem of the underground soil and rock cooling down year by year.

[0039] Low-temperature cooling capacity utilization mechanism: Low-temperature chilled water is given priority to the condensation section, so that the water temperature of the entire packing section is below the dew point temperature, and the entire section is in a high-efficiency condensation condition; the tail water after heating then enters the pre-cooling section to recover sensible heat, realizing the cascade utilization of cooling capacity quality, avoiding the problem in traditional single-stage towers where low-temperature chilled water is directly heated by dry hot air, resulting in excessively high water temperature in the condensation section and inability to dehumidify.

[0040] Pre-cooling and humidification enhance latent heat density: The pre-cooling section first cools the air to a saturated state with equal humidity, eliminating the sensible heat load of the air. After the air enters the condensing section, it immediately enters the deep condensation condition without the need for additional sensible heat cooling. The latent heat recovery per unit packing height is greatly improved, and the latent heat ratio in the condensing section is stable at over 70%. The packing utilization rate is more than 30% higher than that of traditional single-section towers.

[0041] In this embodiment, the entire device relies on a PLC controller to achieve fully automatic operation. The controller input is connected to an ambient temperature sensor 92, a humidity sensor 93, a flow sensor, a power meter 95, and a heat meter 94. These devices are respectively installed on the heat compensation tower, the circulation pipeline, and the U-shaped heat exchanger. Through these devices, the equipment operating parameters can be collected in real time. The outputs control the circulating water pump, exhaust fan, submersible pump, water supply valve, and drain valve. The PLC controller has three sets of operating logic built-in: time-sharing off-peak electricity control, temperature and humidity linkage control, and energy efficiency optimization early warning. It can automatically start and stop the equipment according to the electricity price period, automatically adjust the operating frequency of the fan and water pump according to the outdoor temperature and humidity, and calculate the system's operating energy efficiency in real time. When the energy efficiency is lower than the set threshold for a long time, an alarm is triggered and the machine is shut down to avoid unnecessary power consumption.

[0042] Example 2: like Figure 6 As shown, based on the content of Embodiment 1 above, this embodiment provides an adaptive control system and control method with the core objective of improving latent heat recovery efficiency. The control system is based on a PLC controller. The input end collects parameters such as ambient dry bulb temperature, relative humidity, spray water supply and return water temperature, circulating water flow rate, fan frequency, water pump frequency, system power, and instantaneous heat power in real time. The output end controls the actuators such as the circulating water pump frequency converter, exhaust fan frequency converter, submersible pump, automatic water supply valve, and drain valve.

[0043] The specific steps of the control method include: S1: System initialization, self-test of each sensor and actuator, reading the current time to determine the electricity price period; S2: Real-time acquisition of inlet dry bulb temperature, relative humidity, supply and return water temperature, circulating water flow rate, liquid level and system power; S3: Calculate the air dew point temperature based on the inlet dry-bulb temperature and relative humidity. and obtain the condensation driving force. ; Specifically, based on the real-time collected intake dry-bulb temperature t and relative humidity φ, the dew point temperature of the current air is calculated in real time using the Tetens formula. : Saturated vapor pressure: ; Actual water vapor pressure: ; Dew point temperature: ; Condensation driving force: ; Where t is the inlet dry bulb temperature (°C); φ is the relative humidity of the air (%). The water temperature for the spray system is (°C).

[0044] S4: Determine the COP operation protection threshold based on the current electricity price period; Specifically, the COP threshold is set according to the electricity price period: during off-peak hours, full load operation is prioritized; during normal hours, COP ≥ 10; and during peak hours, COP ≥ 15. Off-peak hours (23:00-7:00): Electricity prices are lowest during this time. At this time, full-load operation is prioritized, and even if the energy efficiency is slightly lower, supplemental heating is continuously provided to maximize the use of off-peak electricity prices and reduce operating costs. During normal power supply periods (7:00-8:00, 11:00-18:00): Normal energy efficiency control. When real-time COP ≥ 10, it will continue to run; when COP < 8, it will automatically shut down.

[0045] Peak power periods (8:00-11:00, 18:00-23:00): Electricity prices are highest during this period. Strict high-efficiency operation is required during this time. The system will only start operating when the real-time COP is ≥15. Otherwise, it will automatically shut down to wait for better operating conditions, ensuring the economic efficiency of operation during peak power periods.

[0046] S5: Determine if the startup conditions are met. Start the system if Δt ≥ 1℃ and the liquid level is normal, and maintain minimum continuous operation. Run time; otherwise, return to S2 to continue testing. ; S6: Based on the interval where Δt is located, automatically adjust the frequency of the water pump and fan according to the rules to optimize the air-water ratio; When Δt < 2℃, it indicates that the condensation driving force is insufficient. At this time, the frequency of the circulating water pump is automatically increased by 10% to 20% to increase the spray flow rate, while the frequency of the exhaust fan is reduced by 10% to 15% to reduce the oncoming wind speed and prolong the gas-liquid contact time, so as to ensure that the water vapor in the condensation section is fully condensed and maintain efficient dehumidification conditions. When 2℃≤Δt≤5℃, it indicates that the condensation driving force is moderate. At this time, both the water pump and the fan maintain the rated frequency operation, balancing the heat exchange efficiency and the air volume. When Δt>5℃, it indicates that the condensation driving force is sufficient. At this time, the frequency of the exhaust fan is dynamically increased by 10% to 25% to increase the air handling capacity, while the frequency of the water pump is appropriately reduced by 5% to 10%. This maximizes the total heat absorption per unit time and reduces the energy consumption of the transmission while ensuring sufficient recovery of latent heat.

[0047] S7: Monitors the system's operating status in real time, executes logic such as liquid level protection, energy efficiency protection, and antifreeze protection, and calculates the system's COP in real time; The system calculates its energy efficiency COP in real time using the following formula: ; In the formula, c is the specific heat capacity of water; ρ is the density of water; and G is the circulating water flow rate. The return water temperature; For water supply temperature, and spray water supply temperature For the same temperature value; For water pump power, For fan power, Power for auxiliary equipment.

[0048] S8: Determine if the shutdown conditions are met. Shut down if any of the following conditions are met; (a) (a) <1℃; (b) COP is below the current time period threshold for 10 consecutive minutes; (c) Liquid level failure cannot be recovered; after shutdown, maintain the minimum downtime; otherwise, return to S2 to continue the cycle control.

[0049] When the real-time COP is below the set threshold (default value is 6) for 10 consecutive minutes, it is determined that the current weather conditions are not suitable for heat replenishment, and the device will automatically shut down to avoid unnecessary power consumption; when the outdoor weather conditions improve, the dew point temperature rises, the condensation driving force recovers to Δt≥3℃ and COP≥10, the device will automatically resume operation.

[0050] When the liquid level is lower than the low liquid level threshold, the automatic water replenishment valve will automatically open to replenish water. If the liquid level does not recover after 5 minutes of replenishment, it is determined to be a water supply failure, and the machine will automatically stop and alarm will sound. At the same time, the liquid level in the collection tank will be monitored, and the submersible pump will be started and stopped and the drain valve will be opened automatically according to the liquid level, so as to achieve fully automatic unattended operation.

[0051] Example 3: This embodiment still uses the gas-water heat exchange soil heat compensation device of Embodiment 1, and based on the specific control method of Embodiment 2, verifies the technical effect of the present invention based on the continuous operation data of an actual engineering project. The test site is a ground source heat pump project in Jinan City, Shandong Province, to carry out actual measurement and verification. The project uses the KZT-5T type enhanced latent heat soil heat compensation tower of the present invention, with 8 underground 100m deep double U32 buried pipe wells, variable frequency circulating water pumps for adjustable speed operation, measured operating flow rate of 2.37m³ / h, and total system input power of about 576W. Continuous tests were carried out under high humidity conditions (14:00-15:00, atmospheric temperature 27~32℃) and medium humidity conditions (13:00-14:00, atmospheric temperature 29~31℃).

[0052] The main equipment parameters of the system are as follows: the open heat exchange tower model is KZT-15T, the rated flow rate is 11.7m³ / h, the fan power is 0.25kW, the packing height is 680mm, the buried pipe heat exchanger adopts 8 vertical buried pipe wells, each well depth is 100m, and double U32 heat exchange tubes are used. The circulating water pump adopts frequency conversion control, the actual operating flow rate is 2.37m³ / h, and the total system power is approximately 576W.

[0053] The actual operating data, measured during the period from 14:00 to 15:00 and corresponding to high temperature and high humidity conditions with an atmospheric temperature of 27–32℃, is shown in Table 1 below.

[0054] Table 1. Measured operating data under high humidity conditions (14:00-15:00) The specific operating data for the test period of 13:00-14:00, corresponding to an ambient temperature of 29-31℃ and an inlet water temperature of 19-22℃ under medium temperature conditions are shown in Table 2 below:

[0055] Table 2. Measured operating data under moderate humidity conditions (13:00-14:00) The measured data above show that the average relative humidity at the air outlet under high humidity conditions reaches 98.7%, proving that the moisture removal process in the condensing section is sufficient and the latent heat recovery effect is stable. The average heat absorption power of the system is 10.48kW, the average COP is 18.19, and the highest COP is 20.55, which is far higher than the existing heat replenishment technology. Within a wide operating range of inlet water temperature of 19-25℃, atmospheric temperature of 27-32℃, and relative humidity of 60%-98%, the system COP remains above 10, demonstrating strong adaptability to operating conditions and the ability to efficiently solve the problem of ground heat imbalance in ground source heat pumps.

[0056] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0057] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A soil and rock heat compensation device for enhancing the absorption of latent heat from the air, characterized in that, The system includes a buried pipe system and a heat compensation system. The heat compensation system includes a heat compensation tower with symmetrical air inlets on both sides of its bottom. Inside the heat compensation tower, from the outside in, are a dust removal section and a water storage section. The water storage section has a water tank. Above the water tank, from the vertical airflow direction, are a heat exchange section, a spray system, and an exhaust section. The buried pipe system includes a heat exchanger embedded in the soil or rock. Both ends of the heat exchanger are connected to the water tank and the spray system via circulation pipes, forming a circulating water path. Inside the heat exchange section, multiple interconnected baffles are arranged vertically in parallel. The baffle cavities are filled with heat exchange packing material. The heat exchange section is divided into a pre-cooling section and a condensation section from bottom to top. A horizontally mounted air distribution baffle is installed at the bottom of the pre-cooling section.

2. The soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 1, characterized in that, The heat compensation tower is a vertical rectangular tower body. The tower body is divided into a bottom horizontal air inlet chamber, a middle vertical heat exchange chamber and an upper exhaust section along the height direction. The dust removal section and water storage section are arranged in the bottom horizontal air inlet chamber, the heat exchange section is located in the middle vertical heat exchange chamber, and the spray system and exhaust section are located in the upper exhaust section. The above functional sections are arranged in sections along the internal space of the tower.

3. The soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 1, characterized in that, The dust removal section includes a filter screen, a dust removal spray system, and an overflow pipe. The filter screen is vertically arranged at the bottom of the heat compensation tower's air duct. The dust removal spray system consists of dust removal nozzles, a submersible pump, and a sewage discharge pipe. A water collection tank is provided at the bottom of the heat compensation tower, corresponding to the dust removal section. The submersible pump is submerged and installed in the water collection tank. The outlet of the submersible pump is connected to the dust removal nozzle. One end of the sewage discharge pipe is connected to the water collection tank, and the other end is connected to an external drainage channel. One end of the overflow pipe is connected to the overflow position at the top of the water collection tank, and the other end is connected to an external drainage channel.

4. The soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 3, characterized in that, The water storage tank is provided with water collection troughs on both the left and right sides. The water storage tank is located in the center of the horizontal air inlet at the bottom of the heat compensation tower. Both the dust removal section and the water storage section are equipped with automatic water replenishment valves, which are connected to the control system via electrical signals.

5. A soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 1, characterized in that, The exhaust section is equipped with an air guide plate, and the exhaust outlet is located on the side wall of the upper part of the heat compensation tower, with an exhaust fan installed at the outlet.

6. The soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 5, characterized in that, The heat compensation tower is equipped with a windbreak wall on its outside, and ventilation openings are reserved on the windbreak wall, which are connected to the air outlet of the exhaust section.

7. The soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 1, characterized in that, The spray system includes multiple sets of spray nozzles evenly arranged at the top of the heat exchange section. The heat exchanger is a U-shaped heat exchanger. A circulating water pump is installed on the circulation pipeline connected to the water storage tank. The circulating water pump is electrically connected to the control system. The circulating water pump delivers low-temperature circulating water to the spray system for spraying from top to bottom, allowing for full contact and heat exchange with the rising air.

8. A soil and rock heat compensation device for enhancing the absorption of latent heat of air as described in claim 3, characterized in that, The dust removal section is also equipped with a water baffle plate, which is arranged between the filter screen and the air inlet. The height of the water baffle plate is higher than that of the overflow pipe. The wind distribution baffle plate is arranged horizontally above the water storage tank, and several ventilation holes are evenly opened on the wind distribution baffle plate.

9. A control method for a gas-water heat exchanger soil heat compensation device as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: System initialization, self-test of each sensor and actuator, and reading the current time to determine the electricity price period; S2: Real-time acquisition of parameters such as inlet dry bulb temperature, relative humidity, supply and return water temperature, flow rate, liquid level, and power; S3: Calculate the air dew point temperature based on the inlet dry-bulb temperature and relative humidity, and obtain the condensation driving force. ; S4: Determine the COP operation protection threshold based on the current electricity price period; S5: Determine if the start-up conditions are met. If Δt≥1℃ and the liquid level is normal, start the system and maintain the minimum continuous running time; otherwise, return to S2 to continue the detection. S6: Based on the interval where Δt is located, automatically adjust the frequency of the water pump and fan according to the rules to optimize the air-water ratio; When Δt < 2℃, the frequency of the circulating water pump is automatically increased by 10% to 20%, the spray flow rate is increased, and the frequency of the exhaust fan is reduced by 10% to 15%. When 2℃≤Δt≤5℃, both the water pump and the fan maintain rated frequency operation to balance heat exchange efficiency and air volume. When Δt>5℃, dynamically increase the exhaust fan frequency by 10% to 25% to increase the air handling capacity, while appropriately reducing the water pump frequency by 5% to 10%. S7: Monitors the system's operating status in real time, executes logic such as liquid level protection, energy efficiency protection, and antifreeze protection, and calculates the system's COP in real time; S8: Determine if the shutdown conditions are met. Shut down if any of the following conditions are met: (a) (a) <1℃; (b) COP is below the current time period threshold for 10 consecutive minutes; (c) Liquid level failure cannot be recovered; after shutdown, maintain the minimum downtime, otherwise return to S2 to continue the cycle control.

10. The control method for a gas-water heat exchanger soil heat compensation device as described in claim 9, characterized in that, The formula for calculating the system COP in S7 is: ； In the formula, c is the specific heat capacity of water; ρ is the density of water; and G is the circulating water flow rate. The return water temperature; For water supply temperature, and spray water supply temperature For the same temperature value; For water pump power, For fan power, Power for auxiliary equipment.

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