KR20250022422A - Geothermal cooling and heating system and method using discharged ground water - Google Patents

Abstract

The present invention relates to a geothermal heating and cooling system using discharged groundwater, which additionally utilizes the energy of discharged groundwater in heating and cooling using geothermal energy. The geothermal heating and cooling system using discharged groundwater according to the present invention comprises: a ground heat exchanger buried in the ground, having a working fluid flowing therein, and absorbing heat from the ground or releasing heat to the ground; a heat pump using geothermal heat transferred through the working fluid as a heat source to cool or heat a heating and cooling fluid of a heating and cooling load device; a working fluid circuit provided between the ground heat exchanger and the heat pump, the working fluid being filled and flowing; and a first discharged water heat exchanger, which is connected to the working fluid circuit and the discharged groundwater transport path, and in which heat exchange between the working fluid and the discharged groundwater is performed.

Description

{Geothermal cooling and heating system and method using discharged ground water}

The present invention relates to a geothermal heating and cooling system and method, and more particularly, to a geothermal heating and cooling system and method using flowing groundwater that additionally utilizes the energy of flowing groundwater when cooling and heating using geothermal energy.

Geothermal energy is the thermal energy of the soil, rocks, and groundwater that make up the underground. Geothermal energy can be developed and utilized regardless of weather or climate conditions, so it is the only renewable energy source that can handle base load and has operating characteristics that make it easy to adjust output according to load conditions.

A geothermal heating and cooling system is an eco-friendly heating and cooling system that uses the ground temperature, which remains constant throughout the year, deep underground to form a heating and cooling cycle with a heat pump, thereby dramatically reducing energy costs and increasing economic efficiency.

Geothermal heating and cooling systems are classified into closed and open systems.

A closed system is a system in which sealed pipes used as ground heat exchangers are buried underground to form a closed circuit system, and the fluid filled inside circulates to absorb heat from the ground or release heat into the ground to provide heating and cooling.

An open system is a system that collects and stores groundwater and supplies it to a heat pump to provide heating and cooling. Depending on the time and location, it may be difficult to secure groundwater in quantity, and direct use of groundwater may be restricted to protect groundwater. Therefore, in the domestic environment, closed systems are actively used rather than open systems.

According to conventional geothermal heating and cooling systems, despite the advantages of utilizing geothermal energy as a heating and cooling source, the number of perforations is limited in places where there is a shortage of perforations, which inevitably leads to insufficient heating and cooling capacity. In urban areas, the site is often narrow, so geothermal perforations are often installed at the bottom of buildings, and in the case of large-scale geothermal heating and cooling systems, there are cases where construction is difficult due to a shortage of perforations.

The present invention has been made to solve the problems of the prior art as described above, and the purpose of the present invention is to provide a geothermal heating and cooling system and method using flowing groundwater, which can satisfy the target heating and cooling capacity by additionally utilizing the heat energy of flowing groundwater even when the geothermal energy used as a heating and cooling heat source is insufficient.

According to a preferred embodiment of the present invention for achieving the above-mentioned purpose, a geothermal heating and cooling system using groundwater discharged therefrom comprises: a ground heat exchanger buried in the ground, having a working fluid flowing therein and absorbing heat from the ground or releasing heat to the ground; a heat pump using the geothermal heat transferred through the working fluid as a heat source to cool or heat a heating and cooling fluid of a heating and cooling load device; a working fluid circuit provided between the ground heat exchanger and the heat pump and in which the working fluid is filled and flows; and a first groundwater heat exchanger connected to the working fluid circuit and the groundwater discharge transport path, where heat exchange between the working fluid and the groundwater discharged therefrom is performed.

The working fluid circulation path is provided in a closed circuit form.

The geothermal heating and cooling system using groundwater discharge according to the present invention further includes a groundwater discharge supply and discharge means for supplying groundwater discharge to a first groundwater discharge heat exchanger or discharging it outdoors.

The effluent supply and drainage means includes: an effluent collection well for collecting effluent groundwater; a permanent drainage pump provided in the effluent collection well; a first effluent drainage channel connecting the permanent drainage pump and the outdoors to form a first drainage path for effluent groundwater; a second effluent drainage channel branched from the first effluent drainage channel and connected to the outdoors to form a second drainage path for effluent groundwater and also connected to the first effluent heat exchanger to form an effluent supply path to the first effluent heat exchanger; an effluent filter provided in the second effluent drainage channel; an effluent tank arranged in the second effluent drainage channel between the effluent filter and the first effluent heat exchanger; and an effluent drainage pump connected to the second effluent drainage channel.

The effluent drainage means further includes an effluent return channel connecting the second effluent drain channel and the effluent tank to return the effluent groundwater passing through the effluent heat exchanger to the effluent tank.

The effluent drainage means further includes an effluent heat exchanger that connects the second effluent drainage channel and the first effluent heat exchanger so that the effluent groundwater in the second effluent drainage channel returns to the second effluent drainage channel after passing through the first effluent heat exchanger.

The working fluid circulation path includes a working fluid supply path that connects the discharge side of the ground heat exchanger and the inlet side of the heat pump and transfers the working fluid that has passed through the ground heat exchanger to the heat pump; and a working fluid return path that connects the inlet side of the ground heat exchanger and the discharge side of the heat pump and transfers the working fluid that has passed through the heat pump to the ground heat exchanger.

The working fluid circulation path further includes a feed water heat exchange path that connects the working fluid feed water path and the first effluent heat exchanger so that the working fluid transferred to the heat pump passes through the first effluent heat exchanger; and a return heat exchange path that connects the working fluid return water path and the first effluent heat exchanger so that the working fluid transferred to the ground heat exchanger passes through the first effluent heat exchanger.

The geothermal heating and cooling system using groundwater discharge according to the present invention further includes a water quality measuring means installed in a groundwater discharge collection well for measuring the water quality of groundwater discharge; and a water level sensor installed in a groundwater discharge tank for measuring the water level of groundwater discharge.

The geothermal heating and cooling system using the groundwater discharged according to the present invention further includes a heating and cooling fluid circuit connecting a heat pump and a heating and cooling load device and having a heating and cooling fluid circulating therein; and a second effluent heat exchanger connected to the heating and cooling fluid circuit and the groundwater discharge transport path, where heat exchange between the heating and cooling fluid and the groundwater discharged is performed.

A geothermal heating and cooling method using groundwater discharge according to a preferred embodiment of the present invention comprises: (a) a step of forming a closed working fluid circuit in which a working fluid circulates between a heat pump and a ground heat exchanger buried in the ground, and transferring geothermal energy to the heat pump via the working fluid; (b) a step of transferring the thermal energy of the groundwater discharge to the working fluid by allowing heat exchange between the groundwater discharge and the working fluid through a first groundwater discharge heat exchanger; and (c) a step of forming a heating and cooling fluid circuit in which a heating and cooling fluid circulates between the heat pump and a heating and cooling load device, and heating or cooling the heating and cooling fluid in the heat pump and then transferring it to the heating and cooling load device.

In step (b), heat exchange between the supply side of the working fluid transferred from the ground heat exchanger to the heat pump and the outflow groundwater, and heat exchange between the return side of the working fluid transferred from the heat pump to the ground heat exchanger and the outflow groundwater are performed together or separately.

The geothermal heating and cooling method using groundwater discharge according to the present invention further includes the step of (d) allowing heat exchange between groundwater discharge and a heating and cooling fluid through a second groundwater discharge heat exchanger.

Step (d) is a pre-cooling and heating process performed before step (b), and is selectively performed depending on the temperature conditions of the discharged groundwater.

According to the geothermal heating and cooling system and method using the groundwater of the present invention, when the energy of the groundwater of the present invention is additionally utilized compared to the case where only geothermal energy is used for heating and cooling, the inlet temperature of the heat pump can be lowered during cooling and higher during heating. Accordingly, the coefficient of performance of the heat pump is increased, so that the cooling and heating efficiency can be improved and the operating cost can be reduced.

In addition, by pre-cooling and heating the cooling and heating load device using the thermal energy of the discharged groundwater when the temperature condition of the discharged groundwater is met, the thermal energy of the discharged groundwater can be sufficiently utilized, which can greatly contribute to improving the cooling and heating efficiency.

Figure 1 is a general configuration diagram of a geothermal heating and cooling system using leaked groundwater according to the first embodiment of the present invention.
Figure 2 is an enlarged drawing of part A of Figure 1.
Figure 3 is an enlarged drawing of section B of Figure 1.
FIG. 4 is a flowchart showing a process of controlling the flow of effluent in a geothermal heating and cooling system using effluent groundwater according to the first embodiment of the present invention.
Figure 5 is a diagram showing the temperature change of the working fluid during cooling.
Figure 6 is a diagram showing the temperature change of the working fluid during heating.
Figure 7 is a graph showing the change in the performance coefficient of a heat pump according to the change in the inlet temperature of the heat pump during heating and cooling.
Figure 8 is a general configuration diagram of a geothermal heating and cooling system using leaked groundwater according to a second embodiment of the present invention.
Figure 9 is an enlarged drawing of part A of Figure 8.
Figure 10 is an enlarged drawing of section B of Figure 8.
Figure 11 is a flowchart showing the process of controlling the operation of the first and second effluent heat exchangers.

Hereinafter, a geothermal heating and cooling system and method using leaked groundwater according to preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is a general configuration diagram of a geothermal heating and cooling system using leaked groundwater according to the first embodiment of the present invention.

A geothermal heating and cooling system using groundwater effluent according to a preferred embodiment of the present invention comprises a ground heat exchanger (10), a heat pump (20), a heating and cooling load device (30), a working fluid circulation path (40), a working fluid circulation pump (50), an effluent heat exchanger (60), and an effluent supply and drainage means (70).

When constructing underground structures such as basements of buildings or subways, construction is often done below the effective groundwater level. When underground areas are developed like this, the groundwater that naturally flows out is called seepage groundwater. If seepage groundwater is left as is, it can cause problems with the safety of underground structures, so it is permanently drained through a pumping system.

In general, groundwater has a high specific heat, so it is colder than the atmosphere in summer and warmer than the atmosphere in winter. The seepage groundwater is an unused energy source that is continuously wasted. The geothermal heating and cooling system according to the present invention utilizes geothermal energy as the main energy source for heating and cooling and uses seepage groundwater as an auxiliary energy source, so that the target heating and cooling capacity can be met even if geothermal energy is insufficient.

The ground heat exchanger (10) is buried in the ground and is configured so that a working fluid flows inside, and the working fluid absorbs heat from the ground or releases heat to the ground. That is, heat exchange occurs between the working fluid and the ground in the ground heat exchanger (10). The working fluid may be a mixture of water and antifreeze.

The heat pump (20) is connected to a ground heat exchanger (10) and a heating and cooling load device (30), receives heat energy from a working fluid passing through the ground heat exchanger (10), generates heating energy or cooling energy, and supplies this energy to a heating and cooling load device (30).

The cooling and heating load device (30) is a device that cools or heats a room and may be provided in the form of an air handling unit (AHU) or a fan coil unit (FCU). In addition, the cooling and heating load device (30) may be provided in various forms (e.g., a water cooler, etc.).

The working fluid circuit (40) circulates the working fluid in a closed circuit between the ground heat exchanger (10) and the heat pump (20).

The working fluid circulation pump (50) is connected to the working fluid circulation path (40) and pumps the working fluid so that it circulates.

The effluent heat exchanger (60) is where the working fluid flowing along the working fluid circulation path (40) and the effluent groundwater exchange heat with each other.

The effluent water supply and drainage means (70) discharges underground effluent groundwater outdoors or supplies it to an effluent water heat exchanger (60). In other words, the effluent water supply and drainage means (70) forms a transport path for effluent groundwater.

Figure 2 is an enlarged drawing of part A of Figure 1.

Fig. 2 shows a structure in which geothermal energy is transferred to a heating and cooling load device (30). Referring to Fig. 2, the geothermal heat exchanger (10), heat pump (20), heating and cooling load device (30), working fluid circuit (40), and working fluid circulation pump (50) will be examined in detail. In addition to the components described above, Fig. 2 also shows a geothermal expansion tank (80), an A valve (V1), and a B valve (V2), and these will also be examined.

The ground heat exchanger (10) is a pipe buried inside a hole drilled vertically in the ground. To prevent problems such as leakage or corrosion, a polyethylene (PE) pipe (hereinafter referred to as a 'PE' pipe) can be used. The ground heat exchanger (10) is filled with a working fluid that circulates between the ground heat exchanger (10) and the heat pump (20). The ground heat exchanger (10) can be a PE pipe bent in a U shape. A plurality of ground heat exchangers (10) can be provided, and the number of installations can vary depending on the target cooling and heating capacity.

The heat pump (20) heats or cools the heating and cooling fluid circulating between the heating and cooling load device (30) and the heat pump (20) using geothermal energy as a heat source during the process in which the refrigerant circulates through a refrigerant cycle consisting of a compressor, a condenser, an expansion valve, and an evaporator. During cooling operation, heat is radiated from the heating and cooling fluid of the heating and cooling load device (30) to the heat pump (20), and the heat released from the heat pump (20) is absorbed by the working fluid, so that the temperature of the working fluid increases. The working fluid, whose temperature has increased, releases heat to the ground while passing through the ground heat exchanger (10). During heating operation, heat is released from the working fluid to the heat pump (20), and the heating and cooling fluid of the heating and cooling load device (30) absorbs heat from the heat pump (20), so that the temperature of the heating and cooling fluid increases. During heating operation, the working fluid absorbs heat from the ground while passing through the ground heat exchanger (10). The number of heat pumps (20) to be installed may vary depending on the target heating and cooling capacity.

As described above, the cooling and heating load device (30) is a device that cools or heats a room, and the number of devices installed may vary depending on the cooling and heating capacity.

The working fluid circuit (40) is provided in a closed circuit form between the ground heat exchanger (10) and the heat pump (20), and is a place where the working fluid is filled and flows inside, providing a passage through which geothermal energy is transferred to the heat pump (20). The working fluid circulation path (40) includes a working fluid supply path (41) that connects the discharge side of the ground heat exchanger (10) and the inlet side of the heat pump (20) to supply working fluid to the heat pump (20), a working fluid return path (42) that connects the discharge side of the heat pump (20) and the inlet side of the ground heat exchanger (10) to recover working fluid from the heat pump (20), a return heat exchange path (43) in which the working fluid flows between the effluent heat exchanger (60) and the working fluid return path (42), and a feed water heat exchange path (44) in which the working fluid flows between the effluent heat exchanger (60) and the working fluid supply path (41).

The working fluid supply line (41) includes a plurality of first supply lines (41a) connected to the discharge sides of a plurality of ground heat exchangers (10), a geothermal supply header (41b) connected to the plurality of first supply lines (41a), a second supply line (41c) connecting the geothermal supply header (41b) and the inlet side of the working fluid circulation pump (50), and a third supply line (41d) connecting the discharge side of the first working fluid circulation pump (50) and the inlet side of the heat pump (20). According to Fig. 2, a plurality of heat pumps (20) are provided, and the third supply lines (41d) are provided in the same number as the heat pumps (20) and can be respectively connected to the heat pumps (20).

The working fluid recovery channel (42) includes a plurality of first recovery lines (42a) each connected to the inlet side of a plurality of ground heat exchangers (10), a geothermal recovery header (42b) connected to the plurality of first recovery lines (42a), and a second recovery line (42c) connecting the geothermal recovery header (42b) and the discharge side of the heat pump (20). When there are a plurality of heat pumps (20), the discharge side of each heat pump (20) can be connected in parallel to the second recovery line (42c).

The recovery heat exchanger (43) connects the second recovery pipe (42c) and the effluent heat exchanger (60) so that the working fluid recovered along the second recovery pipe (42c) passes through the effluent heat exchanger (60). It includes a recovery supply pipe (43a) that supplies the working fluid toward the effluent heat exchanger (60), and a recovery return pipe (43b) that returns the working fluid passed through the effluent heat exchanger (60) back to the second recovery pipe (42c).

The feed water heat exchanger (44) connects the second supply line (41c) and the effluent heat exchanger (60) so that the working fluid supplied along the second supply line (41c) passes through the effluent heat exchanger (60). It includes a feed water supply line (44a) that supplies the working fluid toward the effluent heat exchanger (60), and a feed water return line (44b) that returns the working fluid passing through the effluent heat exchanger (60) back to the second supply line (41c).

Among the pipes forming the working fluid circuit (40), the portion buried underground may be composed of PE pipes, and the portion exposed above ground may be composed of stainless steel (STS) pipes. The pipes buried underground may be made of HDPE (high-density polyethylene) among PE pipes.

The working fluid circulation pump (50) is installed between the second supply pipe (41c) and the third supply pipe (41d) and pumps the working fluid so that it can circulate in the working fluid circulation path (40).

The geothermal expansion tank (80) is connected to the second supply pipe (41c) to control the circulation pressure of the working fluid, thereby ensuring smooth flow of the working fluid.

Valve A (V1) is a three-way valve connected to the connection between the second return pipe (42c) and the return supply pipe (43a), and turns the return flow toward the effluent heat exchanger (60) on/off during the process of returning the working fluid from the heat pump (20) toward the ground heat exchanger (10).

The B valve (V2) is a three-way valve connected to the connection between the second supply pipe (41c) and the water supply pipe (44a), and turns the water flow toward the effluent heat exchanger (60) on and off during the process of supplying the working fluid from the ground heat exchanger (10) toward the heat pump (20).

Meanwhile, a temperature sensor (not shown) is provided at each of a plurality of points along the path through which the working fluid flows to measure the temperature of the working fluid passing through each point and then transmit the temperature to a control unit (not shown). Depending on the temperature detected by each temperature sensor, the operation of the working fluid circulation pump (50), A valve (V1), and B valve (V2) can be automatically controlled by the control unit.

In addition, depending on the temperature of the working fluid, heat exchange between the return of the working fluid and the discharged groundwater through the return heat exchanger (43) and heat exchange between the supply of the working fluid and the discharged groundwater through the supply heat exchanger (44) may be performed together or separately.

Figure 3 is an enlarged drawing of section B of Figure 1.

Figure 3 illustrates structures for discharging groundwater flowing out from underground to the outdoors or supplying it to an effluent heat exchanger (60). In addition, a portion of the recovery heat exchanger (43) and the feedwater heat exchanger (44) illustrated in Figure 2 are also illustrated in Figure 3.

Figure 3 illustrates an effluent heat exchanger (60) and an effluent supply and drainage means (70).

The effluent heat exchanger (60) is a place where heat exchange takes place between the working fluid flowing along the working fluid circulation path (40) and the effluent groundwater, and a plate heat exchanger (e.g., STS304 plate heat exchanger) can be used. A working fluid path through which the working fluid flows and an effluent path through which the effluent groundwater flows are each formed within the effluent heat exchanger (60).

A return water supply pipe (43a) and a feed water supply pipe (44a) are connected to the inlet side of the working fluid path, and a return water return pipe (43b) and a feed water return pipe (44b) are connected to the discharge side of the working fluid path. The return water supply pipe (43a) and the feed water supply pipe (44a) may each be provided with a flow meter (f1)(f2) for measuring the flow rate supplied to the effluent heat exchanger (60).

The effluent heat exchanger (60) is connected to the effluent supply and drainage means (70).

The effluent supply and drainage means (70) includes an effluent collection well (71), a permanent drainage pump (72), a first effluent drainage channel (73), a second effluent drainage channel (74), an effluent filter (75), an effluent tank (76), an effluent drainage pump (77), an effluent return channel (78), an effluent heat exchanger (79), a C valve (V3), a D valve (V4), an E valve (V5), and a water level sensor (not shown).

The runoff water collection well (71) is a facility buried underground to collect runoff groundwater. Depending on the amount of runoff groundwater, one or more may be provided, and each may be equipped with a water quality measuring means (not shown) for measuring the water quality of the runoff groundwater.

A permanent drainage pump (72) is installed in the effluent collection well (71) and pumps out the effluent groundwater collected in the effluent collection well (71) and discharges it to the outside.

The first effluent drainage channel (73) connects the permanent drainage pump (72) to the outdoors to form a first drainage path for effluent, and forms a passage for discharging the effluent groundwater within the effluent collection well (71) to the outside of the effluent collection well (71), i.e., outdoors.

The second effluent drainage channel (74) branches off from the first effluent drainage channel (73) and is connected to the outdoors to form a second drainage path for the effluent groundwater, and is also connected to the effluent heat exchanger (60) to form an effluent supply path to the effluent heat exchanger (60).

The effluent filter (75) is connected to the second effluent drain (74) and filters foreign substances in the effluent groundwater that is transferred to the effluent tank (76). A bucket strainer can be used as the effluent filter (75), and two bucket strainers can be provided. One of the two can be provided as a spare.

The effluent tank (76) is placed between the effluent filter (75) and the effluent heat exchanger (60) in the second effluent drainage channel (74) to form a storage space so that a sufficient amount of effluent groundwater filtered through the effluent filter (75) can be collected before being supplied to the effluent heat exchanger (60). By ensuring a stable supply of effluent to the effluent heat exchanger (60) using the effluent tank (76), stable system operation is possible.

If the effluent groundwater collected in the effluent collection well (71) can be maintained at a constant level above a certain level, the effluent groundwater can be supplied to the effluent heat exchanger (60) without the effluent tank (76). However, if the amount of effluent groundwater cannot be maintained at a constant level in the effluent collection well (71), it is preferable to provide an effluent tank (76) to stably supply the effluent to the effluent heat exchanger (60) as described above.

The effluent drainage pump (77) is connected between the effluent tank (76) and the effluent heat exchanger (60) in the second effluent drainage channel (74) to provide pumping power to discharge the effluent groundwater of the effluent tank (76) to the outdoors.

The effluent recovery channel (78) connects the second effluent drainage channel (74) and the effluent tank (76) to form a passage for recovering the effluent groundwater flowing along the second effluent drainage channel (74) to the effluent tank (76). The recovery of the effluent groundwater through the effluent recovery channel (78) can be controlled according to the temperature of the effluent groundwater discharged from the effluent heat exchanger (60) and the water level of the effluent tank (76). The effluent groundwater discharged from the effluent tank (76) can be supplied entirely to the effluent heat exchanger (60) or only part of it can be supplied to the effluent heat exchanger (60). Depending on the temperature of the effluent groundwater discharged from the effluent heat exchanger (60), the effluent groundwater can be completely discharged outdoors or returned to the effluent tank (76) without being discharged outdoors and then resupplied to the effluent heat exchanger (60). In addition, even when the water level of the effluent tank (76) is low, the effluent groundwater can be returned to the effluent tank (76) to maintain the water level of the effluent tank (76) at an appropriate level.

Meanwhile, the second effluent drainage channel (74) and the effluent heat exchanger (60) are connected via an effluent heat exchange channel (79). The effluent heat exchange channel (79) includes an effluent supply channel (79a) connecting the inlet side of the effluent heat exchanger (60) and the second effluent drainage channel (74), and an effluent return channel (79b) connecting the discharge side of the effluent heat exchanger (60) and the second effluent drainage channel (74). Although not shown in the drawing, a three-way valve-type directional change valve for controlling the supply of effluent to the effluent heat exchanger (60) may be provided at the connection portion between the second effluent drainage channel (74) and the effluent supply channel (79a).

The C valve (V3) is a two-way valve installed at the inlet of the second effluent drain (74) to open and close the flow of groundwater flowing into the second effluent drain (74).

The D valve (V4) is a two-way valve installed at a location away from the outside in the section where the second outflow drain (74) of the first outflow drain (73) is connected, and opens and closes the flow of groundwater outflowing to the outside.

The E valve (V5) is a three-way valve that is provided at the connection between the second effluent drainage channel (74) and the effluent return channel (78) and opens and closes the return flow from the second effluent drainage channel (74) toward the effluent tank (76). That is, when the E valve (V5) is opened toward the outdoors and closed toward the effluent tank (76), the effluent groundwater can be discharged to the outdoors, and when the E valve (V5) is opened toward the effluent tank (76) and closed toward the outdoors, the effluent groundwater can be returned toward the effluent tank (76).

A water level sensor (not shown) is installed in the effluent tank (76) and measures the level of groundwater flowing out of the effluent tank (76).

Meanwhile, the first effluent drainage channel (73) and the second effluent drainage channel (74) may each be equipped with flow meters (f3) (f4) for measuring the amount of groundwater discharged outdoors.

FIG. 4 is a flowchart showing a process of controlling the flow of effluent in a geothermal heating and cooling system using effluent groundwater according to the first embodiment of the present invention.

As described above, the groundwater flowing out from the ground is collected in the runoff collection well (71). The runoff collection well (71) is equipped with a permanent drainage pump (72), so that when the water level inside the runoff collection well (71) reaches a certain height, the permanent drainage pump (72) is operated to discharge the runoff groundwater to the outside. If the permanent drainage pump (72) is not operated, it can be determined that the amount of runoff groundwater collected in the runoff collection well (71) is small and is not discharged to the outside. When the permanent drainage pump (72) is not operated, the C valve (V3) is closed and the D valve (V4) is opened.

When the permanent drainage pump (72) is operated, the water quality measured by the water quality measuring means installed in the effluent collection well (71) is analyzed, and if the water quality is in good condition satisfying the standard conditions, it can be determined that it can be supplied to the effluent tank (76). If the water quality does not satisfy the standard conditions, it is determined that it cannot be supplied to the effluent tank (76), and the entire amount is discharged outdoors. If the water quality does not satisfy the standard conditions, the C valve (V3) is closed and the D valve (V4) is opened. If it is determined that it is necessary to supply the effluent groundwater to the effluent tank (76) even though the water quality does not satisfy the standard conditions, the effluent groundwater can be treated with chemicals to adjust the water quality to the standard conditions. For example, the pH concentration of the effluent groundwater can be adjusted to the standard conditions by treating it with chemicals.

If the water quality of the effluent groundwater in the effluent collection well (71) is good, before supplying the effluent groundwater to the effluent tank (76), it is determined whether the water level in the effluent tank (76) is below an appropriate range. That is, if the water level in the effluent tank (76) is above an appropriate high water level, there is no need to supply the effluent groundwater into the effluent tank (76), so the effluent groundwater can be controlled to be supplied only when the water level in the effluent tank (76) is below the appropriate high water level. If the water level in the effluent tank (76) is above the appropriate high water level, the C valve (V3) closes and the D valve (V4) opens, so that the effluent groundwater is discharged outdoors. If the water level in the effluent tank (76) is below the appropriate high water level, the C valve (V3) opens and the D valve (V4) closes, so that the effluent groundwater can be supplied to the effluent tank (76).

The effluent groundwater collected in the effluent tank (76) is discharged outdoors by the operation of the effluent drainage pump (77). In this process, some or all of the effluent groundwater passes through the effluent heat exchanger (60) and is then discharged outdoors. Depending on the temperature conditions of the effluent passing through the effluent heat exchanger (60), it may not be discharged outdoors but may be returned to the effluent tank (76). That is, if the temperature of the effluent passing through the effluent heat exchanger (60) is within a temperature range capable of heat exchange with the working fluid circulating along the working fluid circuit (40), it may be returned and used for heat exchange.

As the effluent through the effluent heat exchanger (60) is discharged outdoors, the amount of effluent groundwater in the effluent tank (76) can be reduced. If the water level of the effluent tank (76) is below an appropriate low water level, the operation of the effluent drainage pump (77) can be stopped and the discharge of effluent groundwater through the second effluent drainage channel (74) can be stopped.

When the water level of the effluent tank (76) is higher than the appropriate low water level, the effluent drainage pump (77) continues to operate and the effluent groundwater is continuously discharged through the second effluent drainage channel (74). During this process, the effluent groundwater continues to pass through the effluent heat exchanger (60). When the temperature of the effluent groundwater passing through the effluent heat exchanger (60) satisfies a certain condition, the effluent groundwater can be returned to the effluent tank (76). At this time, the outdoor drainage side of the E valve (V5) is closed and the effluent tank (76) side is opened. When the temperature of the effluent groundwater passing through the effluent heat exchanger (60) does not satisfy a certain condition, the effluent groundwater is discharged outdoors. At this time, the outdoor drainage side of the E valve (V5) is opened and the effluent tank (76) side is closed.

By repeating the above control process while heating and cooling are in progress, the flow of groundwater can be effectively controlled.

Figure 5 is a diagram showing the temperature change of the working fluid during cooling. Figure 5 shows an example of the temperature change in a closed geothermal system when cooling a room by additionally utilizing the energy of the groundwater in addition to geothermal energy.

In general, in a closed geothermal system, the inlet temperature to be introduced into the heat pump (20) during cooling is designed to be 30°C. Fig. 5 shows the change in temperature of the working fluid when the initial inlet temperature during cooling is set to the general design temperature and the energy of the flowing groundwater is additionally utilized in addition to the geothermal energy. The change in temperature of the working fluid can be determined by measuring the temperature at points ① to ⑥ and checking the value.

The working fluid is introduced into the heat pump (20) at a temperature of 30°C (point ①). The working fluid introduced into the heat pump (20) absorbs heat within the heat pump (20) and then is discharged. The working fluid discharged from the heat pump (20) has a temperature distribution of 35°C (point ②).

The working fluid discharged from the heat pump (20) passes through the effluent heat exchanger (60) in the process of being returned toward the ground heat exchanger (10), and here, heat is released toward the effluent groundwater. The temperature of the effluent groundwater supplied to the effluent heat exchanger (60) is 20°C, and the temperature of the effluent groundwater discharged from the effluent heat exchanger (60) is 22°C. In general, the effluent groundwater maintains a temperature of about 10 to 25°C, although this may vary depending on the depth of the underground layer.

The working fluid is cooled during the process of passing through the effluent heat exchanger (60) and then returns to the recovery path and heads to the geothermal recovery header (42b). The temperature of the working fluid heading to the geothermal recovery header (42b) has a distribution of 33°C (point ③). This is about 2°C lower than when it was discharged from the heat pump (20).

When the working fluid is recovered through the geothermal recovery header (42b) to the ground heat exchanger (10) buried in the ground, the working fluid releases heat into the ground, thereby lowering the temperature further and having a temperature distribution of 30°C (point ④). Generally, the temperature of the ground is estimated to be maintained at approximately 13 to 18°C. Since the temperature of the working fluid flowing through the ground heat exchanger (10) is higher than the ground temperature, the heat of the working fluid is released into the ground, thereby lowering the temperature of the working fluid.

The working fluid passing through the geothermal heat exchanger (10) passes through the geothermal supply header (41b) and its temperature is maintained at 30°C (point ⑤).

The working fluid passing through the geothermal supply header (41b) releases heat toward the effluent groundwater during the process of passing through the effluent heat exchanger (60) and then returns to the working fluid supply channel (41). The temperature of the working fluid returning to the working fluid supply channel (41) through the effluent heat exchanger (60) drops to 28°C (point ⑥).

As can be seen from Fig. 5, the initial entering temperature (EWT: Entering Water Temperature) of the working fluid introduced into the heat pump (20) during the cooling process is 30°C, but after heat exchange with the effluent groundwater through the effluent heat exchanger (60), the entering temperature is confirmed to be lowered to 28°C.

Figure 6 is a diagram showing the temperature change of the working fluid during heating. Figure 6 shows an example of the temperature change in a closed geothermal system when heating a room by additionally utilizing the energy of the flowing groundwater in addition to geothermal energy.

In general, in a closed geothermal system, the inlet temperature to be introduced into the heat pump (20) for heating is designed to be 5℃. Fig. 6 shows the change in temperature of the working fluid when the initial inlet temperature for heating is set to the general design temperature and the energy of the flowing groundwater is additionally utilized in addition to the geothermal energy. The change in temperature of the working fluid can be determined by measuring the temperature at points ① to ⑥ and checking the value.

The working fluid is introduced into the heat pump (20) at an initial inlet temperature of 5°C (point ①). The working fluid introduced into the heat pump (20) releases heat within the heat pump (20) and then is discharged. The working fluid discharged from the heat pump (20) has a temperature distribution of 1°C (point ②).

The working fluid discharged from the heat pump (20) passes through the effluent heat exchanger (60) in the process of being returned toward the ground heat exchanger (10), where it absorbs heat from the effluent groundwater. The temperature of the effluent groundwater supplied to the effluent heat exchanger (60) is 15°C, and the temperature of the effluent groundwater discharged from the effluent heat exchanger (60) is 13°C. In general, the effluent groundwater maintains a temperature of about 10 to 25°C, although this may vary depending on the depth of the underground layer. The temperature of the effluent groundwater may be lower in winter than in summer.

The working fluid is heated during the process of passing through the effluent heat exchanger (60) and then returns to the recovery path and heads to the geothermal recovery header (42b). The temperature of the working fluid heading to the geothermal recovery header (42b) has a distribution of 3℃ (point ③). The temperature is about 2℃ higher than when discharged from the heat pump (20).

When the working fluid is returned to the ground heat exchanger (10) buried in the ground via the geothermal recovery header (42b), the working fluid absorbs heat from the ground, thereby increasing its temperature and having a temperature distribution of 5℃ (point ④). In general, the temperature of the ground is estimated to be maintained at about 13 to 18℃. Since the temperature of the working fluid flowing through the ground heat exchanger (10) is lower than the ground temperature, the heat of the ground is transferred to the working fluid, thereby increasing the temperature of the working fluid.

The working fluid passing through the geothermal heat exchanger (10) passes through the geothermal supply header (41b) and its temperature is maintained at 5°C (point ⑤).

The working fluid passing through the geothermal supply header (41b) absorbs heat from the effluent groundwater while passing through the effluent heat exchanger (60) and then returns to the working fluid supply channel (41). The temperature of the working fluid returning to the working fluid supply channel (41) through the effluent heat exchanger (60) rises to 7°C (point ⑥).

As can be seen from Fig. 6, the initial inlet temperature of the working fluid introduced into the heat pump (20) during the heating process is 5°C, but after heat exchange with the effluent groundwater through the effluent heat exchanger (60), the inlet temperature can be confirmed to increase to 7°C.

Fig. 7 is a graph showing the change in the performance coefficient of a heat pump according to the change in the inlet temperature of the heat pump during cooling and heating. Fig. 7 (a) is a graph showing the change in the performance coefficient of a heat pump during cooling, and Fig. 7 (b) is a graph showing the change in the performance coefficient of a heat pump during heating. In each graph of Fig. 7, the X-axis represents the inlet temperature, and the Y-axis represents the performance coefficient.

The coefficient of performance (COP) of the heat pump (20) changes depending on the inlet temperature of the working fluid. It can be seen that the coefficient of performance increases as the inlet temperature decreases during cooling and as the inlet temperature increases during heating. For example, when the inlet temperature is 30°C during cooling, the coefficient of performance is about 4.76, when it is 29°C, it is about 4.91, and when it is 28°C, it is about 5.04, so the coefficient of performance of the heat pump increases as the inlet temperature decreases.

As the performance coefficient improves, the operating cost can be reduced. As examined in FIGS. 5 and 6, compared to the case of using only geothermal energy for heating and cooling, when the energy of the flowing groundwater is additionally utilized, the inlet temperature of the heat pump is lowered by about 2℃ for cooling and higher by about 2℃ for heating. That is, as can be seen in FIG. 7, the performance coefficient of the heat pump is improved when the flowing groundwater is additionally utilized for heating and cooling compared to the case of using only geothermal energy for heating and cooling.

Figure 8 is a general configuration diagram of a geothermal heating and cooling system using leaked groundwater according to a second embodiment of the present invention.

According to the geothermal heating and cooling system using the discharged groundwater according to the second embodiment of the present invention, the heating and cooling performance can be further improved by further providing a structure that allows direct heat exchange between the heating and cooling load device (30) and the discharged groundwater. That is, if the temperature condition of the discharged water tank (76) (the temperature condition of the discharged groundwater) is a condition that allows direct heat exchange with the heating and cooling load device (30), heat exchange between the discharged groundwater and the heating and cooling load device (30) can be performed before the heat exchange using the heat pump (20) using the concept of pre-cooling or pre-heating, that is, the concept of pre-cooling and heating.

To this end, the second embodiment of the present invention may be provided with two effluent heat exchangers (60A) (60B). The first effluent heat exchanger (60A) has the same connection structure as the effluent heat exchanger (60) of the first embodiment of the present invention, and the second effluent heat exchanger (60B) is additionally provided for heat exchange between the effluent groundwater and the cooling and heating load device (30). The second effluent heat exchanger (60B) may be selectively operated depending on the temperature condition of the effluent groundwater measured in the effluent tank (76).

The first and second effluent heat exchangers (60A)(60B) are connected in parallel to the second effluent drain (74).

Figure 9 is an enlarged drawing of part A of Figure 8.

A heating and cooling fluid circulates between the heat pump (20) and the heating and cooling load device (30).

As described above, an air conditioner or a fan coil unit may be used as the cooling and heating load device (30). At this time, the path through which the cooling and heating fluid circulates is configured as a closed circuit, and the cooling and heating fluid may be water or a mixture of water and antifreeze. Meanwhile, a chiller or hot water heater may be used as the cooling and heating load device (30). At this time, the cooling and heating fluid may be water, and the path through which the cooling and heating fluid circulates may be configured as an open circuit.

A heating and cooling fluid circuit (90) is formed between the heat pump (20) and the heating and cooling load device (30) in which the heating and cooling fluid circulates. The heating and cooling fluid circuit (90) includes a heating and cooling fluid supply pipe (91) connecting the inlet side of the heat pump (20) and the outlet side of the heating and cooling load device (30), a heating and cooling fluid return pipe (92) connecting the outlet side of the heat pump (20) and the inlet side of the heating and cooling load device (30), and a bypass pipe (93) directly connecting the heating and cooling fluid supply pipe (91) and the heating and cooling fluid return pipe (92).

A heating and cooling fluid heat exchanger (100) connected to a second effluent heat exchanger (60B) is connected to the heating and cooling fluid circulation path (90). The heating and cooling fluid heat exchanger (100) includes a water supply pipe (101) connecting the inlet side of the second effluent heat exchanger (60B) and the heating and cooling fluid supply pipe (91), and a water return pipe (102) connecting the discharge side of the second effluent heat exchanger (60B) and the heating and cooling fluid supply pipe (91). The point where the cooling and heating fluid supply pipe (91) and the water supply pipe (101) are connected is located between the bypass pipe (93) and the cooling and heating load device (30), and the point where the cooling and heating fluid supply pipe (91) and the water return pipe (102) are connected is located between the water supply pipe (101) and the bypass pipe (93).

A three-way valve-type F valve (V6) is provided at the connection point between the heating and cooling fluid supply pipe (91) and the water supply pipe (101), thereby changing the flow direction of the heating and cooling fluid. A three-way valve-type G valve (V7) is provided at the connection point between the heating and cooling fluid return pipe (92) and the bypass pipe (93), thereby changing the flow direction of the heating and cooling fluid.

A heating and cooling fluid circulation pump (110) is connected to the heating and cooling fluid supply pipe (91) to allow the heating and cooling fluid to flow along the heating and cooling fluid circulation path (90) or the heating and cooling fluid heat exchange path (100).

As described above, if the temperature condition of the effluent tank (76) (temperature condition of the effluent groundwater) is such that direct heat exchange with the heating and cooling load device (30) is possible, heat exchange between the effluent groundwater and the heating and cooling load device (30) can be performed directly before heat exchange using the heat pump (20).

In this case, the F valve (V6) opens toward the heating and cooling load device (30) and the second effluent heat exchanger (60B), and closes toward the heat pump (20). In the case of the G valve (V7), it opens toward the bypass pipe (93) and the heating and cooling load device (30), and closes toward the heat pump (20). Therefore, the heating and cooling fluid discharged from the heating and cooling load device (30) flows along the heating and cooling fluid supply pipe (91) and undergoes heat exchange with the effluent groundwater while passing through the second effluent heat exchanger (60B). The heating and cooling fluid that has passed through the second effluent heat exchanger (60B) is then returned to the heating and cooling load device (30) through the heating and cooling fluid supply pipe (91), the bypass pipe (93), and the heating and cooling fluid return pipe (92).

This type of pre-cooling/heating process can be accomplished when the cooling/heating fluid can obtain sufficient energy for pre-cooling/heating through the groundwater without passing through a heat pump (20).

If the energy required for pre-cooling and heating cannot be sufficiently obtained through heat exchange with the effluent groundwater, the energy required for pre-cooling and heating can be supplemented by having the heating and cooling fluid passing through the second effluent heat exchanger (60B) pass through the heat pump (20). In this case, the G valve (V7) is opened toward the heating and cooling load device (30) and the heat pump (20) and closed toward the bypass pipe (93), so that the heating and cooling fluid passing through the second effluent heat exchanger (60B) passes through the heat pump (20) without passing through the bypass pipe (93) and is then returned to the heating and cooling load device (30).

Figure 10 is an enlarged drawing of section B of Figure 8.

As described above, the first and second effluent heat exchangers (60A) (60B) are connected in parallel to the second effluent drainage channel (74). The second effluent drainage channel (74) and the inlet and outlet sides of each effluent heat exchanger (60A) (60B) are connected by separate connecting pipes. An H valve (V8) and an I valve (V9) are respectively provided at the portion where the connecting pipes connected to the inlet sides of the first and second effluent heat exchangers (60A) (60B) and the second effluent drainage channel (74) are connected to control the supply of effluent groundwater to the first and second effluent heat exchangers (60A) (60B).

In the second effluent heat exchanger (60B), an effluent path through which effluent groundwater passes and a heating and cooling fluid path through which heating and cooling fluid passes are formed.

Both the first and second effluent heat exchangers (60A) (60B) can be provided in the form of plate heat exchangers.

Figure 11 is a flowchart showing the process of controlling the operation of the first and second effluent heat exchangers.

Figure 11 shows the entire control process, including the process of determining whether heating and cooling is possible in advance using only the discharged groundwater before heating and cooling using geothermal heat + discharged groundwater is performed, and then performing pre-cooling and heating (pre-cooling or pre-heating) if it is determined to be possible.

Before starting heating and cooling using geothermal heat + groundwater outflow, it is first determined whether the conditions for pre-cooling and heating are met. The possible conditions for pre-cooling and heating can be determined by the temperature difference between the indoor temperature and the outflow groundwater. For example, if the temperature difference between the indoor temperature and the outflow groundwater is greater than the set value, it can be determined that pre-cooling and heating are possible, and if it is less than the set value, it can be determined that the pre-cooling and heating conditions are not met.

When the pre-cooling and heating conditions are satisfied, the second effluent heat exchanger (60B) must be used, so the opening and closing states of the valve involved in supplying effluent to the second effluent heat exchanger (60B) and the valve involved in supplying cooling and heating fluid to the second effluent heat exchanger (60B) must be controlled.

That is, when the pre-cooling and heating conditions are satisfied, in the case of the F valve (V6), the second effluent heat exchanger (60B) side is opened and the heat pump (20) side is closed, in the case of the H valve (V8), the first effluent heat exchanger (60A) side is closed and the outdoor drain side is opened, and in the case of the I valve (V9), the second effluent heat exchanger (60B) side is opened and the outdoor drain side is closed.

If the pre-cooling and heating conditions are not satisfied, the second effluent heat exchanger (60B) is not used and only the first effluent heat exchanger (60A) is used. Therefore, before using the first effluent heat exchanger (60A), it is first determined whether its usage conditions are satisfied. As the usage conditions of the first effluent heat exchanger (60A), whether the return temperature of the working fluid during cooling is higher than the temperature of the effluent groundwater, whether the return temperature of the working fluid during heating is lower than the temperature of the effluent groundwater, whether the temperature of the working fluid passing through the geothermal supply header (41b) during cooling is higher than the temperature of the effluent groundwater, and whether the temperature of the working fluid passing through the geothermal supply header (41b) during heating is lower than the temperature of the effluent groundwater, etc. are determined.

When the conditions for use of the first effluent heat exchanger (60A) are satisfied, in the case of the F valve (V6), the second effluent heat exchanger (60B) side is closed and the heat pump (20) side is opened, in the case of the H valve (V8), the first effluent heat exchanger (60A) side is opened and the outdoor drain side is closed, in the case of the I valve (V9), the second effluent heat exchanger (60B) side is closed and the outdoor drain side is opened, in the case of the A valve (V1), the first effluent heat exchanger (60A) side is opened and the geothermal recovery header (42b) side is closed, and in the case of the B valve (V2), the first effluent heat exchanger (60A) side is open and the heat pump (20) side is closed.

If the conditions for use of the first effluent heat exchanger (60A) are not satisfied, in the case of the H valve (V8), the first effluent heat exchanger (60A) side is closed and the outdoor drainage side is opened, in the case of the I valve (V9), the second effluent heat exchanger (60B) side is closed and the outdoor drainage side is opened, in the case of the A valve (V3), the first effluent heat exchanger (60A) side is closed and the geothermal recovery header (42b) side is opened, and in the case of the B valve (V4), the first effluent heat exchanger (60A) side is closed and the heat pump (20) side is opened.

As described above, the geothermal heating and cooling system and method using groundwater discharge according to preferred embodiments of the present invention have been described in detail with reference to the attached drawings, but the present invention is not limited to the above-described embodiments, and may be implemented in various modified forms within the scope of the patent claims. For example, in the embodiments of the present invention, only liquids are exemplified as working fluids and heating and cooling fluids, but the present invention is not limited thereto and gases may also be used.

10: Ground heat exchanger 20: Heat pump
30: Cooling and heating load device 40: Working fluid circulation path
41: Working fluid supply channel 42: Working fluid return channel
43: Recovery heat exchanger 44: Feed water heat exchanger
50: Working fluid circulation pump 60: Effluent heat exchanger
70: Effluent drainage means 71: Effluent collection well
72: Permanent drainage pump 73: First effluent drain
74: Second effluent drain 75: Effluent filter
76: Effluent tank 77: Effluent drain pump
78: Effluent recovery channel 79: Effluent heat exchange channel
80: Geothermal expansion tank 90: Heating and cooling fluid circuit
91: Heating and cooling fluid supply pipe 92: Heating and cooling fluid return pipe
93: Bypass pipe 100: Heating and cooling fluid heat exchanger
101: Water supply pipe 102: Water return pipe
110: Heating and cooling fluid circulation pump

Claims (14)

A ground heat exchanger that is buried in the ground and has a working fluid flowing inside it, absorbing heat from the ground or releasing heat to the ground;
A heat pump that cools or heats the heating and cooling fluid of a heating and cooling load device using geothermal heat transferred through a working fluid as a heat source;
A working fluid circulation path provided between the above-mentioned ground heat exchanger and the heat pump and in which the working fluid is filled and flows; and
A first effluent heat exchanger, which is connected to the working fluid circulation path and the effluent groundwater transport path, and in which heat exchange between the working fluid and the effluent groundwater is performed;
Geothermal heating and cooling system using groundwater. In the first paragraph,
The above working fluid circulation path is provided in a closed circuit form.
Geothermal heating and cooling system using groundwater. In the first paragraph,
Further comprising an effluent water supply and drainage means for supplying the effluent groundwater to the first effluent water heat exchanger or discharging it outdoors.
Geothermal heating and cooling system using groundwater. In the third paragraph,
The above-mentioned effluent supply and drainage means are,
A runoff collection well where runoff groundwater is collected;
A permanent drainage pump provided in the above effluent collection tank;
A first effluent drainage channel connecting the above permanent drainage pump and the outdoors to form a first drainage path for effluent;
A second effluent drainage channel branched from the first effluent drainage channel and connected to the outdoors to form a second drainage path for effluent groundwater, and also connected to the first effluent heat exchanger to form an effluent supply path to the first effluent heat exchanger;
An effluent filter provided in the second effluent drain;
An effluent tank disposed between the effluent filter and the first effluent heat exchanger in the second effluent drain; and
Including a drainage pump connected to the second drainage channel;
Geothermal heating and cooling system using groundwater. In paragraph 4,
The above-mentioned effluent supply and drainage means are,
Further comprising an effluent recovery channel connecting the second effluent drainage channel and the effluent tank to recover effluent groundwater passing through the effluent heat exchanger to the effluent tank.
Geothermal heating and cooling system using groundwater. In paragraph 5,
The above-mentioned effluent supply and drainage means are,
Further comprising an effluent heat exchanger connecting the second effluent drainage channel and the first effluent heat exchanger so that effluent in the second effluent drainage channel returns to the second effluent drainage channel after passing through the first effluent heat exchanger.
Geothermal heating and cooling system using groundwater. In the first paragraph,
The above working fluid circulation path is:
A working fluid supply channel that connects the discharge side of the above-mentioned ground heat exchanger and the inlet side of the above-mentioned heat pump, and transfers the working fluid passing through the above-mentioned ground heat exchanger to the above-mentioned heat pump; and
A working fluid recovery path that connects the inlet side of the ground heat exchanger and the discharge side of the heat pump, and transfers the working fluid passing through the heat pump to the ground heat exchanger;
Geothermal heating and cooling system using groundwater. In Article 7,
The above working fluid circulation path is:
A feed water heat exchanger that connects the above working fluid feed water channel and the first effluent heat exchanger so that the working fluid transferred to the heat pump passes through the first effluent heat exchanger; and
Further comprising a recovery heat exchanger that connects the working fluid recovery channel and the first effluent heat exchanger so that the working fluid transferred to the ground heat exchanger passes through the first effluent heat exchanger;
Geothermal heating and cooling system using groundwater. In paragraph 4,
A water quality measuring means provided in the above-mentioned effluent collection well for measuring the quality of effluent groundwater; and
Further comprising a water level sensor provided in the above effluent tank for measuring the effluent groundwater level;
Geothermal heating and cooling system using groundwater. In the first paragraph,
A heating and cooling fluid circulation path connecting the above heat pump and the heating and cooling load device and in which heating and cooling fluid circulates inside; and
Further comprising a second effluent heat exchanger connected to the above cooling and heating fluid circulation path and the above effluent groundwater transport path, in which heat exchange between the above cooling and heating fluid and the effluent groundwater takes place;
Geothermal heating and cooling system using groundwater. (a) a step of configuring a working fluid circuit in which a working fluid circulates between a heat pump and a ground heat exchanger buried in the ground, and transferring geothermal energy to the heat pump through the working fluid;
(b) a step of transferring the heat energy of the effluent groundwater to the working fluid by allowing heat exchange between the effluent groundwater and the working fluid through the first effluent heat exchanger; and
(c) a step of configuring a heating and cooling fluid circulation path through which heating and cooling fluid circulates between the heat pump and the heating and cooling load device, thereby heating or cooling the heating and cooling fluid in the heat pump and then delivering it to the heating and cooling load device; including;
Geothermal heating and cooling method using leaked groundwater. In Article 11,
In the step (b) above, heat exchange between the supply side of the working fluid transferred from the ground heat exchanger to the heat pump and the outflow groundwater, and heat exchange between the return side of the working fluid transferred from the heat pump to the ground heat exchanger and the outflow groundwater are performed together or separately.
Geothermal heating and cooling method using leaked groundwater. In Article 11,
(d) a step of allowing heat exchange between the effluent groundwater and the heating/cooling fluid through a second effluent heat exchanger; further comprising;
Geothermal heating and cooling method using leaked groundwater. In Article 13,
The above step (d) is a pre-cooling and heating process performed before the above step (b), and is selectively performed depending on the temperature conditions of the discharged groundwater.
Geothermal heating and cooling method using leaked groundwater.

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