JP2018025347A - Heat exchange system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchange system having improved availability.SOLUTION: A heat exchange system 1 includes: an outer cylinder 11 that is erected in an underground GRD hole and reaches a plurality of aquifers WBL1, WBL2, WBL3 having different depth and into which groundwater is caused to flow via slits 13 provided on the side surface; an inner cylinder 12 that is accommodated in the outer cylinder 11 and into which groundwater is caused to flow via water passing holes 14 provided on the lower side; water pumping means 8 for pumping up the groundwater in the inner cylinder 12 from a position shallower than the water passing holes 14 to generate a convection current from the lower side toward the upper side in the inner cylinder 12; and a circulation pipe 3 that is drawn from a heat pump 7 on the ground into the inner cylinder 12, caused to extend downwards, folded back upwards and drawn out to outside of the inner cylinder 12 so as to circulate liquid sent out from the heat pump 7. Heat is transferred between the groundwater in the inner cylinder 12 and the liquid flowing in the circulation pipe 3.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a heat exchange system using groundwater.

  Due to rising crude oil prices and increased awareness of CO2 reduction, heat pumps that use geothermal heat (hereinafter referred to as geothermal heat pumps), which are low in running costs and are clean energy, have been developed and introduced into the market.

  The geothermal heat pumps disclosed in Patent Documents 1 and 2 flow a liquid such as water through a U tube built in a well, and exchange heat between the groundwater in the well and the liquid flowing in the U tube. By that, get the geothermal heat.

Japanese Patent No. 5067956 Japanese Patent No. 5690960

  In such a geothermal heat pump, it is required to promote differentiation from other heat exchange systems and enhance utility value by improving heat exchange efficiency.

  This invention is made | formed in view of the said subject, and it aims at providing the heat exchange system which raised the utility value.

  (1) The present invention is a cylinder erected in a hole in the ground that reaches one aquifer or a plurality of aquifers of different depths, and groundwater flows into the inside through a flooded part on the side surface. An outer cylinder that is housed in the outer cylinder, and an inner cylinder into which groundwater flows into the inside through a water passage portion provided below, and the groundwater in the inner cylinder is more than the water passage portion. By pumping up from a shallow position, pumping means for generating convection from below to above in the inner cylinder, and being drawn into the inner cylinder from the ground heat pump and passed downward, and upward And a circulation pipe that circulates the liquid drawn out of the inner cylinder and sent out from the heat pump, and moves heat between the groundwater in the inner cylinder and the liquid flowing in the circulation pipe It is the heat exchange system characterized by this.

  According to the present invention, even if groundwater flows into a hole in the ground from only the upper aquifer among a plurality of aquifers, The groundwater that has flowed into the hole is not immediately pumped up, and the groundwater that has flowed in can be convected in the hole in the ground. And by the convection which arose in the underground hole, heat can be efficiently moved between the groundwater in the underground hole and the liquid flowing through the circulation pipe. Thereby, the utility value of a heat exchange system increases.

  (2) The present invention also includes a first water temperature meter that measures the temperature of ground water in the outer tube or the inner tube, a second water temperature meter that measures the temperature of ground water pumped up by the pumping means, Whether the water supply means functions based on the combination of the water supply means for returning the groundwater pumped up by the pumping means into the outer cylinder, and the measurement result of the first water temperature gauge and the measurement result of the second water temperature gauge. The heat exchanging system according to (1), further comprising: a control unit that determines whether or not to control the water supply unit.

  According to the said invention, when a water supply means is functioned, the discharge | emission amount of the groundwater outside a system can be suppressed. When there is little effect on the transfer of heat between the groundwater in the underground hole and the liquid flowing through the circulation pipe based on the combination of the measurement result of the first thermometer and the measurement result of the second thermometer By making the water supply means function, it is possible to simultaneously achieve both effective use of geothermal heat and suppression of the amount of drainage. Thereby, the utility value of a heat exchange system increases.

  (3) According to the present invention, the water supply means returns the groundwater pumped up by the pumping means to a position shallower than the water passing portion in the outer cylinder, so that the water supply means moves downward from above into the outer cylinder. The heat exchange system according to (2) above, wherein the convection is directed.

  According to the above invention, the groundwater returned into the outer cylinder does not immediately flow into the inner cylinder via the water flow section, and the returned groundwater can be convected within the outer cylinder. Then, the ground water in the outer cylinder and the ground water in the inner cylinder are obtained by bidirectional convection of the upper to lower convection generated in the outer cylinder and the lower to upper convection generated in the inner cylinder. And heat can be efficiently transferred between the two. Thereby, the utility value of a heat exchange system increases.

  (4) According to the present invention, the pumping means includes a pumping pipe having one end drawn into the inner cylinder and the other end reaching the outside of the hole in the ground, and groundwater in the pumping pipe. The water supply means includes a switching valve provided in the middle of the pumping pipe, one end connected to the switching valve, and the other end of the outer cylinder. The heat exchange system according to (2) or (3), wherein the heat exchange system includes a water pipe drawn into the interior.

  According to the above invention, it is possible to perform both discharge of groundwater to the outside of the system and return to the outer cylinder of the groundwater pumped up from the inner cylinder only by providing one power source called a pump. it can. Thereby, the utility value of a heat exchange system increases.

  According to the present invention, the utility value of the heat exchange system is increased.

It is the schematic of the heat exchange system which concerns on embodiment of this invention. It is a block diagram which shows the structure of a control panel.

  Hereinafter, with reference to drawings, the heat exchange system concerning the embodiment of the present invention is explained in detail.

  First, the structure of the heat exchange system 1 is demonstrated using FIG.1 and FIG.2. FIG. 1 is a schematic diagram of a heat exchange system 1. FIG. 2 is a block diagram showing the configuration of the control panel 21. Note that in each drawing, a part of the configuration is omitted as appropriate to simplify the drawing.

  The heat exchange system 1 shown in FIG. 1 is a heat pump (ground heat pump) system that uses underground heat. The heat exchange system 1 is controlled centrally by a control panel 21. That is, the heat exchange system 1 operates under the control of the control panel 21, and the operation state is managed by the control panel 21. Specifically, the heat exchange system 1 is feedback-controlled based on the measurement results of thermometers arranged at various places so that the operation of each unit is in a desired state.

  Such a heat exchange system 1 includes a well 2, a circulation pipe 3, a circulation pump 4, a groundwater temperature measurement pipe 5, a circulating liquid thermometer 6, a heat pump 7, a pumping means 8, a pumping thermometer ( (Second water temperature gauge) 9, water supply means 10, control panel 21 and the like.

  The well 2 is a hole in the underground GRD that reaches a plurality of aquifers WBL1, WBL2, and WBL3 having different depths, and includes an outer cylinder 11 and an inner cylinder 12 having different diameters. Each aquifer WBL1, WBL2, WBL3 is a geological layer containing groundwater.

  The outer cylinder 11 is a bottomed cylinder erected in a hole in the underground GRD, and is provided with dredged sand SS for improving water permeability, and is groundwater through a slit (flooded portion) 13 on the side surface. Flows into the interior. Groundwater flows into the outer cylinder 11 from the aquifers WBL1, WBL2, and WBL3. It is preferable to have the slit 13 in the depth corresponding to each aquifer WBL1, WBL2, WBL3, and is provided in the outer cylinder 11 suitably. In such an outer cylinder 11, an inner cylinder 12 is accommodated, and a groundwater temperature measurement pipe 5 and a water supply pipe 18 are inserted.

  The inner cylinder 12 is a bottomed cylinder accommodated in the outer cylinder 11, and groundwater flows into the inside through a water passage hole (water passage portion) 14 provided below. Inside the inner cylinder 12, groundwater flows from the aquifers WBL 1, WBL 2, WBL 3 through the outer cylinder 11. The natural water level of the groundwater flowing into the inner cylinder 12 (shown by a one-dot chain line) matches the natural water level of the groundwater flowing into the outer cylinder 11 (the natural water level outside the inner cylinder 12). Yes. The water passage hole 14 has a structure in which the groundwater flowing into the inner cylinder 12 becomes a turbulent flow. In such an inner cylinder 12, a circulation pipe 3 and a pumping pipe 15 are inserted.

  It should be noted that the position “downward” where the inner cylinder 12 has the water passage holes 14 is preferably as low as possible. However, convection from the lower side to the upper side in the inner cylinder 12 by the pumping means 8 described later. As long as the position of the inner cylinder 12 is not limited, the position near the middle of the inner cylinder 12 is not excluded.

  The circulation pipe 3 is drawn into the inner cylinder 12 from the heat pump 7 on the ground and passed downward, and is folded upward at the lower side of the inner cylinder 12 and drawn out of the inner cylinder 12. The circulation pipe 3 circulates a liquid such as water sent from the heat pump 7 by the power of the circulation pump 4. Thereby, heat can be transferred between the ground water in the inner cylinder 12 and the liquid flowing through the circulation pipe 3. That is, the heat exchange system 1 cools the liquid flowing through the circulation pipe 3 when the groundwater in the inner cylinder 12 is at a lower temperature than the liquid flowing through the circulation pipe 3. On the other hand, the heat exchange system 1 heats the liquid flowing through the circulation pipe 3 when the groundwater in the inner cylinder 12 is hotter than the liquid flowing through the circulation pipe 3.

  The circulation pump 4 is provided in the middle of the circulation pipe 3 and operates based on the measurement result of the groundwater thermometer (first water temperature gauge) 5b constituting the groundwater temperature measurement pipe 5 or the measurement result of the circulating fluid thermometer 6. To do. Thereby, the circulation pump 4 circulates the liquid in the circulation pipe 3 by applying power to the liquid in the circulation pipe 3.

  The groundwater temperature measuring tube 5 is inserted into the outer cylinder 11. The groundwater temperature measuring pipe 5 includes a pipe body 5a and a plurality of groundwater thermometers 5b. The plurality of groundwater thermometers 5b are attached to the pipe body 5a at a predetermined interval (for example, at an interval of 10 m). The plurality of groundwater thermometers 5 b measure the temperature of groundwater in the outer cylinder 11, output the measurement result as a signal, and input the signal to the control panel 21.

  The circulating fluid thermometer 6 is provided in the middle of the circulation pipe 3. The circulating fluid thermometer 6 measures the temperature of the liquid in the circulation pipe 3 before the heat transfer between the groundwater in the outer cylinder 11 and outputs the measurement result as a signal. To enter.

  The heat pump 7 is connected to the circulation pipe 3 and the like. The heat pump 7 collects the cold or hot heat of the liquid flowing through the circulation pipe 3 and makes the collected cold or hot heat available for air conditioning or hot water supply. That is, the heat pump 7 takes out the cold or hot water of the groundwater that has moved to the liquid in the circulation pipe 3 in the well 2 and makes it available for air conditioning and hot water supply.

  The pumping means 8 draws groundwater in the inner cylinder 12 from a position shallower than the water passage hole 14 of the inner cylinder 12, thereby generating convection in the inner cylinder 12 from below to above. Specifically, the pumping means 8 includes a pumping pipe 15 and a pumping pump 16.

  One end of the pumping pipe 15 is drawn into the inner cylinder 12, and the other end reaches the outside of the well 2 (such as a drainage facility). The pumping pipe 15 discharges groundwater taken from the inner cylinder 12 by the power of the pumping pump 16 to the outside of the well 2.

  The pumping pump 16 is provided in the middle of the pumping pipe 15 and operates based on the measurement result of the groundwater thermometer 5b constituting the groundwater temperature measuring pipe 5, the measurement result of the circulating fluid thermometer 6, and the like. This pumping pump 16 takes in groundwater from the inner cylinder 12 to the pumping pipe 15 and applies power to the groundwater in the pumping pipe 15.

  The pumping thermometer 9 is provided in the middle of the pumping pipe 15. The pumping thermometer 9 measures the temperature of groundwater in the pumping pipe 15 pumped up by the pumping means 8, outputs the measurement result as a signal, and inputs the signal to the control panel 21.

  The water supply means 10 returns the groundwater pumped up by the pumping means 8 to a shallow position in the outer cylinder 11, thereby causing convection in the outer cylinder 11 from the upper side to the lower side.

  In addition, the “shallow position” in the outer cylinder 11 for returning the groundwater is preferably as shallow as possible, and is particularly preferably a position near the natural water level or a position above the natural water level. A position where convection from the upper side to the lower side is generated in the outer cylinder 11 by returning the groundwater, that is, a position shallower than the water passage hole 14, may be a position near the middle of the outer cylinder 11 or below the outer cylinder 11. It does not mean to exclude the position of.

  Specifically, the water supply means 10 includes a switching valve 17 and a water supply pipe 18.

  The switching valve 17 is provided in the middle of the pumping pipe 15 and operates based on the measurement result of the groundwater thermometer 5b constituting the groundwater temperature measurement pipe 5, the measurement result of the pumped water thermometer 9, and the like. The switching valve 17 switches the path of the groundwater pumped up by the pumping means 8 between a pumping pipe 15 reaching the outside of the well 2 and a water pipe 18 drawn into the outer cylinder 11.

  One end of the water supply pipe 18 is connected to the switching valve 17, and the other end is drawn into the outer cylinder 11. The water pipe 18 returns the ground water pumped up by the pumping means 8 into the outer cylinder 11.

  As shown in FIG. 2, the control panel 21 includes a data logger 22 and a CPU (Central Processing Unit) 23.

  The data logger 22 is configured by a recording medium such as a RAM (Random Access Memory). The data logger 22 stores a processing program for the CPU 23 to execute various processes, various data (including data used by the determination unit 25 for determination) and various flags used when executing the various processes. Yes.

  The CPU 23 functions as the communication unit 24, the determination unit 25, and the control unit 26 by executing the processing program stored in the data logger 22.

  The communication unit 24 transmits and receives signals to and from each unit of the heat exchange system 1. Specifically, the communication unit 24 transfers signals output from the groundwater thermometer 5 b, the circulating fluid thermometer 6, the pumped water thermometer 9, and the like constituting the groundwater temperature measuring pipe 5 to the determination unit 25. And the communication part 24 transfers the control signal which the control part 26 outputs to the circulation pump 4, the heat pump 7, the pumping pump 16, and the switching valve 17. FIG.

  The determination unit 25 performs various determinations based on signals output from the groundwater thermometer 5b, the circulating fluid thermometer 6, the pumped water thermometer 9, and the like that constitute the groundwater temperature measuring pipe 5, thereby the circulation pump 4 and the heat pump 7. The operation status of each of the pumping pump 16 and the switching valve 17 is determined. Then, the determination unit 25 outputs the determination result as a signal to the control unit 26.

  The control unit 26 outputs a control signal based on the signal output from the determination unit 25 via the communication unit 24 to each of the circulation pump 4, the heat pump 7, the pumping pump 16, the switching valve 17, and the like. Control the driving situation.

  Such a CPU 23 determines whether or not to make the water supply means 10 function based on the combination of the measurement result of the groundwater thermometer 5b and the measurement result of the pumped thermometer 9, and serves as a control means for controlling the water supply means 10. Function.

  Next, the heat flow in the heat exchange system 1 will be described with reference to FIG.

  First, the case where air conditioning is performed in the summer will be described. The heat pump 7 collects cold heat from the liquid flowing through the circulation pipe 3, and uses the collected cold heat for cooling. The liquid flowing through the circulation pipe 3 is heated by the heat pump 7. The liquid in the circulation pipe 3 heated by the heat pump 7 is cooled when the ground water in the inner cylinder 12 is heated, and can be used again by the heat pump 7. Groundwater in the inner cylinder 12 heated by the liquid flowing through the circulation pipe 3 is transferred from the aquifers WBL1, WBL2, and WBL3 through the outer cylinder 11, pumped by the pumping means 8, or with the atmosphere. Cooled by contact etc.

  Next, a case where heating or hot water supply is performed in winter will be described. The heat pump 7 collects heat from the liquid flowing through the circulation pipe 3 and uses the collected heat for heating and hot water supply. The liquid flowing through the circulation pipe 3 is cooled by the heat pump 7. The liquid in the circulation pipe 3 cooled by the heat pump 7 is heated when the ground water in the inner cylinder 12 is cooled, and can be used again by the heat pump 7. The groundwater in the inner cylinder 12 cooled by the liquid flowing through the circulation pipe 3 is transferred to the groundwater via the outer cylinder 11 from the aquifers WBL1, WBL2 and WBL3, pumped by the pumping means 8, or to the atmosphere. Heated by contact or the like.

  As described above, according to the heat exchange system 1, it is assumed that groundwater flows into the underground GRD hole (well 2) only from the upper aquifer WBL1 among the aquifers WBL1, WBL2, and WBL3. Even in other cases, groundwater that has flowed into the underground GRD hole (well 2) is not immediately pumped up, and the groundwater that has flowed into the underground GRD hole (well 2) Can be convected inside. And, by the convection generated in the underground GRD hole (well 2), heat is efficiently transferred between the groundwater in the underground GRD hole (well 2) and the liquid flowing through the circulation pipe 3. Can be moved. Thereby, the utility value of the heat exchange system 1 increases.

  Moreover, when the water supply means 10 is functioned, the amount of groundwater discharged outside the system can be suppressed. Based on the combination of the measurement result of the groundwater thermometer 5b and the measurement result of the pumped thermometer 9, heat transfer between the groundwater in the underground GRD hole (well 2) and the liquid flowing in the circulation pipe 3 By making the water supply means 10 function when there is little influence on the water, it is possible to achieve both effective use of geothermal heat and suppression of the amount of drainage at the same time. Thereby, the utility value of the heat exchange system 1 increases.

  Furthermore, since the groundwater pumped up by the pumping means 8 is returned to a shallow position, the groundwater returned into the outer cylinder 11 does not immediately flow into the inner cylinder 12 through the water passage hole 14 and is returned. The groundwater can be convected in the outer cylinder 11. Then, the ground water in the outer cylinder 11 and the inner cylinder are obtained by bidirectional convection of the upper cylinder from the upper cylinder and the lower cylinder convection generated in the outer cylinder 11 and the lower cylinder convection generated in the inner cylinder 12. The heat can be efficiently transferred between the groundwater in 12. Thereby, the utility value of the heat exchange system 1 increases.

  Moreover, only by providing one power source called the pumping pump 16, both discharge of the groundwater to the outside of the system and return of the groundwater pumped up from the inside of the inner cylinder 12 to the outer cylinder 11 can be performed. . Thereby, the utility value of the heat exchange system 1 increases.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit and technical idea thereof. That is, the position, size, length, quantity, shape, material, timing, and the like of each component can be changed as appropriate.

  That is, in the said embodiment, although the case where the water supply means 10 functioned by the motive power by the pumping pump 16 which comprises the pumping means 8 was demonstrated to the example, this invention is not limited to this, Even if the water supply means for pumping up the ground water and returning it into the outer cylinder 11 is provided with a water pump different from the pump 16 constituting the pumping means 8, it functions independently of the pumping means 8. good.

  Or in the said embodiment, although the case where the groundwater temperature measurement pipe | tube 5 was inserted in the outer cylinder 11 was demonstrated to the example, this invention is not limited to this, The temperature of the groundwater in the well 2 is shown. The ground water temperature measuring tube 5 may be inserted into the inner cylinder 12 as long as it can be measured.

  Or in the said embodiment, although the case where the heat exchanging system 1 was provided in the hole of underground GRD which reaches several aquifers WBL1, WBL2, WBL3 from which depth differs was described as an example, this invention is to this It is not limited, The heat exchange system 1 may be provided in the hole of underground GRD which reaches one aquifer. The depth of one aquifer may be shallow or deep, and the heat exchange system 1 may be provided so as to penetrate the aquifer as long as it reaches the aquifer.

DESCRIPTION OF SYMBOLS 1 Heat exchange system 2 Well 3 Circulation pipe 4 Circulation pump 5 Groundwater temperature measurement pipe 5a Pipe body 5b Groundwater thermometer (1st water thermometer)
6 Circulating fluid thermometer 7 Heat pump 8 Pumping means 9 Pumping thermometer (second water thermometer)
10 Water supply means 11 Outer cylinder 12 Inner cylinder 13 Slit (submerged part)
14 Water hole (water passage)
DESCRIPTION OF SYMBOLS 15 Pumping pipe 16 Pumping pump 17 Switching valve 18 Water supply pipe 21 Control panel 22 Data logger 23 CPU
24 communication unit 25 determination unit 26 control unit WBL1, WBL2, WBL3 Aquifer GRD Underground SS Silica sand

Claims (4)

A cylinder standing in a hole in the ground that reaches one aquifer or a plurality of aquifers with different depths, an outer cylinder into which groundwater flows into the inside through a flooded part on the side surface;
An inner cylinder into which the groundwater flows into the inside through a water passage portion located below, which is accommodated in the outer cylinder;
Pumping up the groundwater in the inner cylinder from a position shallower than the water flow section, thereby generating convection from below to above in the inner cylinder;
A circulation pipe that circulates the liquid fed from the heat pump, drawn from the ground heat pump into the inner cylinder and passed downward, and folded upward and drawn out of the inner cylinder. ,
A heat exchange system, wherein heat is transferred between ground water in the inner cylinder and liquid flowing in the circulation pipe. A first water thermometer for measuring the temperature of ground water in the outer cylinder or the inner cylinder;
A second water temperature meter for measuring the temperature of the groundwater pumped up by the pumping means;
Water supply means for returning the groundwater pumped up by the pumping means into the outer cylinder;
Control means for determining whether to function the water supply means based on a combination of the measurement result of the first water temperature meter and the measurement result of the second water temperature gauge, and for controlling the water supply means. The heat exchange system according to claim 1, wherein: The water supply means returns the groundwater pumped up by the pumping means to a position shallower than the water flow portion in the outer cylinder, thereby generating convection from the upper side to the lower side in the outer cylinder. The heat exchange system according to claim 2. The pumping means is
One end is drawn into the inner cylinder, and the other end reaches the outside of the underground hole,
A pump for applying power to the groundwater in the pumping pipe, and
The water supply means is
A switching valve provided in the middle of the pumping pipe,
The heat exchange system according to claim 2, further comprising: a water pipe having one end connected to the switching valve and the other end drawn into the outer cylinder.

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