JP2012087976A - Ground water use heat exchange system and ground water use heat exchange equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ground water use heat exchange system which has superior thermal efficiency, and ground water use heat exchange equipment which is easily installed and maintained suitably to the system.SOLUTION: A casing 1 which is installed in the ground and constitute a well for water pumping and returning by backfilling an outer peripheral part is provided with an upper screen 2 and a lower screen 3. The inside of the casing 1 is partitioned into a side of the upper screen 2 and a side of the lower screen 3 by a packer 31 so that it makes possible to alternately switch an operation for pumping water from the side of the upper screen 2 in the casing 1 and returning the pumped water into the ground from the side of the lower screen 3 and an operation for pumping water from the side of the lower screen 3 and returning the pumped water into the ground from the side of the upper screen 2. The backfilled part of the outer periphery of the casing 1 is filled with water blocking materials i1, i2 above the position of the upper screen 2 and in the middle between the position of the upper screen 2 and the position of the lower screen 3 according to the layer at the installation position to prevent the ground water from causing a shortcut.

Description

  The present invention relates to a groundwater-based heat exchange system used for air conditioning such as air conditioning, hot water supply, snow melting, cooling of machinery and equipment in a factory, and the like, and a groundwater-based heat exchange facility suitable for the system.

  There are two main types of geothermal use for air conditioning: a ground heat exchange type that uses a heat collection tube such as a U tube that circulates the heat medium, and a groundwater use type that directly pumps and uses ground water. Since there are advantages and disadvantages, a conditionally advantageous one is selected according to the environment and cost of the installation location.

  Among these, for example, there are inventions described in Patent Documents 1 to 3 as an improvement technique of a groundwater utilization type underground heat utilization system.

  In Patent Document 1, a single well that serves both as intake water and circulating water for a plurality of aquifers is provided, and the interior is partitioned vertically by a packer, and a heat pump device is installed in the well and installed in the well By selectively operating the two pumps or by switching the groundwater supply path with a single pump, the groundwater taken from one of the aquifers is supplied to the heat pump device and the other A heat pump facility that uses groundwater as a heat source configured to circulate water in the aquifer is disclosed.

  And according to invention of this patent document 1, it is supposed that a highly efficient heat pump driving | running can be performed over the whole year, and the construction cost and required installation space of a well can be reduced significantly.

  Patent Document 2 discloses a heat pump system in which an upper strainer and a lower strainer are provided in one well, and a well is provided between the upper strainer and the lower strainer to divide the well into two. .

  According to the invention described in Patent Document 2, groundwater can be taken and reduced by a single well, and a heat pump can be operated throughout the year with high efficiency. Conventionally, a groundwater pumping well and a reducing well are used. However, it is said that the pump can be pumped up and returned by one well, and the cutting cost and installation space of the well can be greatly reduced.

  Furthermore, in Patent Document 3 and Non-Patent Document 1, in order to solve the problem of clogging in Patent Document 2, a movable separation device that separates the inside of the casing up and down is arranged to be movable up and down in the casing in the well. The lower pipe and the upper pipe are inserted into the casing, the upper screen portion 2 is formed in the upper casing 1 of the movable separation device, and the lower screen portion is formed in the lower casing of the movable separation device. When the amount of water injected from the upper chamber in the casing has decreased or periodically, the pumping function of the lower pipe and the injection function of the upper pipe are switched to each other, and the upper pipe in the upper casing of the movable separator is passed through the upper pipe. Opened groundwater heat exchange method and device that pumps groundwater from the side chamber and injects groundwater after heat utilization into the lower chamber in the lower casing of the movable separator through the lower pipe and returns it to the ground. It is.

  According to the invention described in Patent Document 3, the clogging of the lower screen portion of the lower chamber or the clogging of the upper screen portion of the upper chamber is eliminated by the reverse flow of the groundwater, and the reverse of the screen portion due to the reverse flow of the groundwater. It is said that washing can be performed regularly or when the amount of injected water is reduced to maximize the use of groundwater heat, and efficient use and heat exchange can be performed using groundwater heat. .

Japanese Patent No. 3600992 Japanese Patent Laid-Open No. 9-280689 JP 2010-117081 A

Minami Yuzhen, Ryuzo Ooka, Yoshiro Shiba, Tetsuo Okumura, “Study on Development of Groundwater Circulation Type Air Water Cooling Hybrid Heat Pump System (Part 1) Outline of SCW System and Construction of Experimental Equipment” -2, pp.1105-1106, 2008

  The invention described in Patent Document 1 described above is to install a heat pump device having a refrigerant circulation system including a compressor, an expansion valve, and the like at a slightly upper position of a packer in a well (Patent Document 1, paragraph 0014-0015). Refer to), installation in the well and maintenance is difficult and impractical.

  Further, in the invention described in Patent Document 3, which is an improvement of the invention described in Patent Document 2, as a movable separation device, a balloon or the like is formed of rubber or a rubber-like elastic body, and a fluid such as air is formed inside by a pumping tube. A packer having a structure that is compressed by being pumped and expanded, and contracted by extracting air inside, still has problems in installation and maintenance.

  In addition, the inventions described in Patent Document 2 and Patent Document 3 constitute a relatively shallow well mainly intended for use in houses and the like, and the casing is merely partitioned by a packer. So-called shortcuts where groundwater to be returned and groundwater to be returned are mixed in the ground are likely to occur, which may reduce thermal efficiency.

  The invention of the present application is intended to solve the above-described problems in the prior art, and the use of groundwater in which the casing constituting a single well is partitioned by a packer and pumping and returning water can be performed with one well. It is an object of the present invention to provide a groundwater heat exchange system with excellent thermal efficiency and a groundwater heat exchange facility suitable for the system and easy to install and maintain.

  The invention according to claim 1 of the present application is an upper screen portion that is installed in the ground, backfills the outer peripheral portion, and forms a well for pumping and returning water, and allows groundwater to enter and leave the ground. In the groundwater-based heat exchange system that provides a lower screen part, partitions the inside of the casing into an upper screen part side and a lower screen part side by a packer, and enables pumping and returning water to the ground in a single well. The backfill portion on the outer periphery of the casing is filled with a water shielding material above the position of the upper screen portion and between the position of the upper screen portion and the position of the lower screen portion according to the formation at the casing installation position. Thus, it is characterized by preventing a short-circuit between the groundwater to be pumped and the groundwater to be returned.

  The structure in which the casing is partitioned into an upper screen part side and a lower screen part side by a packer, and pumping and returning water to the ground with a single well is the same as in Patent Documents 2 and 3, In the invention, in consideration of the flow of groundwater in the ground, groundwater to be pumped and groundwater to be returned are prevented from being mixed in the ground.

  In the present invention, it is assumed that a well having a large depth of about 30 to 70 m or more is used instead of the shallow well targeted by Patent Documents 2 and 3, and a viscous soil or the like is interposed between them as in the invention described in Patent Document 1. If the water is pumped and returned with the impermeable soil layer interposed therebetween, it is possible to prevent the groundwater to be pumped and the groundwater to be returned from mixing in the ground.

  In the present invention, not only in such a case, but in general, by utilizing the fact that groundwater is more likely to penetrate in the horizontal direction than in the vertical direction due to slight soil differences even within the same formation, the backfill portion of the outer periphery of the casing As for the upper screen part position, and between the upper screen part position and the lower screen part position, according to the formation of the casing installation position, respectively, by filling each with a water shielding material, each from a narrow formation range targeted Therefore, it is possible to more efficiently prevent a short-circuit between the groundwater to be pumped and the groundwater to be returned.

  The water shielding material used for the backfill portion is not particularly limited as long as it is a material that can provide the necessary water shielding properties, such as clay-based materials including bentonite, curable resin-based materials, and asphalt-based materials.

  According to a second aspect of the present invention, in the groundwater-based heat exchange system according to the first aspect, by switching a plurality of pumps, water is pumped from the upper screen portion side in the casing and returned to the ground from the lower screen portion side. The operation and the operation of pumping water from the lower screen portion side and returning water from the upper screen portion side to the ground can be switched.

  The casing is divided into an upper screen part side and a lower screen part side by a packer, pumping water from the upper screen part side in the casing, returning water from the lower screen part side to the ground, and pumping from the lower screen part side The configuration that enables switching between the operation of returning water from the upper screen portion side to the ground is the same as that of Patent Document 3, thereby preventing clogging in the upper screen portion and the lower screen portion. .

  In this case, as a pump for pumping, by providing a submersible pump on each of the upper screen part side and the lower screen part side partitioned by the packer, pumping and switching can be performed efficiently even with a small pump.

  In addition, as described in claim 1, the present invention considers the flow of groundwater in the ground, and appropriately arranges a water shielding material in the backfill portion on the outer periphery of the casing, thereby targeting a narrow formation range. It is possible to efficiently pump and return water from the ground, efficiently prevent a short-circuit between the groundwater to be pumped and the groundwater to be returned, and improve the thermal efficiency of the groundwater-based heat exchange system.

  A groundwater-use heat exchange facility according to claim 3 of the present application is a groundwater-use heat exchange facility used in the groundwater-use heat exchange system according to claim 2, and is installed in the ground and used for the pumped and returned water well. A casing having an upper screen portion and a lower screen portion, and an interior pipe having a water passage portion arranged at a predetermined interval in the radial direction inside the casing and communicating with the upper screen portion of the casing; An upper lid provided in the upper part of the interior pipe, a lower packer and a seal material provided in a lower part of the interior pipe and partitioning the inside of the casing into an upper screen part side and a lower screen part side, and pumping at a lower end And a submersible pump for pumping water from the interior pipe, and a submersible pump for pumping at the lower end. A lower pumping pipe for penetrating the lower packer and pumping water from a lower part in the casing; an upper return water hole formed in the upper lid; a lower return water hole formed in the lower packer; And a return water pipe penetrating through the upper lid and connected to the lower return water hole.

  The upper return water hole is for returning water pumped from the lower pump pipe and used for heat exchange from the upper screen part to the ground through the water passing part of the interior pipe.

  The lower return water hole is for returning water pumped from the upper pumping pipe and used for heat exchange from the lower screen part to the ground through the lower part of the casing below the inner pipe.

  In the invention of Patent Document 3 mentioned in the background art section, since a balloon-shaped movable separation device as a packer moves up and down along the inner surface of the casing, it takes time and labor for installation and maintenance. In the invention, since the lower packer is provided at the lower part of the interior pipe inserted inside the casing, the upper cover is provided at the upper part, and the pipes and the like are attached thereto, the equipment for pumping and returning water can be unitized. Installation and maintenance in the casing is easy.

  In addition, submersible pumps for pumping are arranged above and below the lower packer of the interior pipe, and by switching between these operations, the pumping path and the return water path can be reversed to prevent performance degradation due to clogging in the screen section. .

  In addition, a metal pipe, a resin hose, etc. can be used for an upper pumping pipe, a lower pumping pipe, a return water pipe, etc.

  In addition, the upper return water hole and the lower return water hole may be simple holes, but may be provided with a packing pipe or a connection socket.

  In addition, the interior pipe inserted inside the casing can be made of inexpensive synthetic resin pipes such as vinyl chloride pipes, in which case rust etc. even when installed near the coast and affected by seawater There is no problem of corrosion.

  According to a fourth aspect of the present invention, in the groundwater-use heat exchange facility according to the third aspect, the water flow portion is formed by a large number of small holes or slits formed in a pipe wall of the interior pipe. It is.

  This water flow portion is provided in the vicinity of the position of the upper screen portion of the casing, and groundwater is pumped and returned through the water flow portion and the upper screen portion.

  Claim 5 is the groundwater-use heat exchange facility according to claim 3 or 4, wherein the upper cover body constitutes the upper cover of the interior pipe and the casing, and the upper pump pipe, the lower pump pipe, A socket for connection is provided at the position of the upper return water hole and the return water pipe.

  The fifth aspect is a case where the upper lid body also serves as a lid of the casing portion. In addition, when making an upper cover body into a cover body only of an interior pipe, only an interior pipe can also be raised / lowered within a casing.

  A sixth aspect of the present invention is the groundwater heat exchange facility according to the third, fourth or fifth aspect, wherein the lower packer constitutes a lower lid of the interior pipe, and the lower pumping pipe and the lower return water hole A socket for connection is provided at the position.

  The present invention does not directly divide the casing up and down as in the inventions described in Patent Documents 1 to 3, but is configured to be divided inside and outside the interior pipe, so that unitization is easy. .

  Moreover, the assembly as a unit becomes easy by providing the socket.

  According to the groundwater-use heat exchange facility of the present invention, the backfill portion on the outer periphery of the casing is located above the upper screen portion position, between the upper screen portion position and the lower screen portion position, according to the formation at the casing installation position. By filling each with a water shielding material, it is possible to efficiently prevent a short-circuit between the groundwater to be pumped and the groundwater to be returned and maintain high thermal efficiency.

  According to the groundwater-use heat exchange facility of the present invention, the interior pipe inserted into the casing and the upper lid and lower packer, pipes, etc. positioned above and below the interior pipe can be assembled as one unit and installed in the casing. And easy maintenance.

  In addition, an inexpensive synthetic resin pipe can also be used for the interior pipe, and in that case, it is excellent in resistance to seawater and the like.

  The submersible pumps for pumping are disposed above and below the lower packer of the interior pipe, and by switching between these operations, the pumping path and the return water path can be reversed to prevent performance degradation due to clogging in the screen section.

1 shows an embodiment of the present invention, (a) is a vertical sectional view showing an embodiment of the groundwater-based heat exchange system and groundwater-based heat exchange equipment of the present invention, (b) is a geological column diagram of the applicable ground. It is. FIGS. 1A and 1B show an example of an upper lid body in the embodiment of FIG. 1, wherein FIG. 1A is a plan view and FIG. 1B is a partial cross-sectional view. FIGS. 1A and 1B show an example of a lower packer in the embodiment of FIG. 1, in which FIG. 1A is a plan view and FIG.

  Hereinafter, embodiments of the present invention will be described in detail. Note that the present invention is not limited to the embodiments described below.

  1 to 3 show an embodiment of the present invention, and FIG. 1 is related to a geological column diagram of the ground to which the groundwater-based heat exchange system of the present invention is applied. FIG. 2 shows the entire structure (the piping on the ground and the air conditioning equipment in the building are omitted because there is no particular difference from the conventional groundwater heat exchange equipment), and FIG. Shows the details of the lower packer part.

  In the casing 1 that is installed in the ground and forms a well, an upper screen for allowing groundwater to pass between the ground and the ground during pumping and returning water as in the inventions described in Patent Documents 1 to 3 described above. A part 2 and a lower screen part 3 are formed.

  In the present embodiment, the inner pipe 11 is disposed inside the casing 1 at a predetermined interval in the radial direction. On the pipe wall of the inner pipe 11, a water passage portion 12 made up of a large number of small holes 13 or slits is formed at a position corresponding to the vicinity of the position of the upper screen portion 2 of the casing 1. Groundwater is pumped and returned through the upper screen portion 2 of 1.

  An upper lid 21 constituting the upper lid of the inner pipe 11 and the casing 1 is attached to the upper part of the inner pipe 11. On the lower surface side of the upper lid 21, a connection socket 22 is provided at positions of an upper pumping pipe 41, a lower pumping pipe 51, an upper return water hole 61, and a return water pipe 81 which will be described later. In addition, a cable hole 25 is provided with packing for passing cables of upper and lower submersible pumps 42 and 52 described later.

  Further, a connection port 23 having a connection flange 24 for connecting to the ground pipe is provided on the upper surface side of the upper lid 21, and a connection flange (not shown) provided at the end of the ground pipe. And the connecting flange 24 of the upper lid 21 can be connected with bolts.

  A lower packer 31 is attached to the lower part of the interior pipe 11. The lower packer 31 is provided with a connection socket 32 at a position of a return water pipe 81 connected to a lower pumping pipe 51 and a lower return water hole 71 described later. A cable hole 35 is provided with packing for passing a cable of a lower submersible pump 52 described later.

  In addition, the casing 1 is partitioned into an upper screen portion 2 side and a lower screen portion 3 side by interposing a sealing material 35 between the inner peripheral surface of the casing 1 and the outer peripheral surface of the lower portion of the interior pipe 11. .

  In such a configuration, by operating the submersible pump 42 attached to the lower end of the upper pumping pipe 41, it was taken into the interior pipe 11 through the upper screen part 2 of the casing 1 and the water passage part 12 of the interior pipe 11. Groundwater (with little temperature change throughout the year, cooler than air temperature in summer, warmer than air temperature in winter) is pumped from the upper pumping pipe 41 and used for air conditioning of buildings through ground piping (not shown). .

  On the other hand, the groundwater used for air conditioning of the building passes through the interior pipe 11 and is returned to the lower part of the interior pipe 11 through the return water pipe 81 connected to the lower return water hole 71, and the lower screen portion of the casing 1. Returned to ground from 3.

  Moreover, when the submersible pump 52 attached to the lower end of the lower pumping pipe 51 is operated, groundwater is pumped from the lower pumping pipe 51 through the lower screen part 3 of the casing 1, and air conditioning of the building is performed through ground piping (not shown). Used for etc.

  On the other hand, the groundwater used for air conditioning of the building enters the interior pipe 11 through the upper return water hole 61 provided in the upper lid body 21, and passes through the water passing portion 12 of the interior pipe 11 and the upper screen portion 2 of the casing 1. It is returned to the ground through.

  By switching between the upper and lower submersible pumps 42 and 52, the flow of groundwater passing through the upper screen portion 2 and the lower screen portion 3 of the casing 1 is reversed, and clogging can be prevented.

  The positions of the upper screen portion 2 and the lower screen portion 3 of the casing 1 are set so that the groundwater to be pumped and the groundwater to be returned are not easily mixed according to the geology (stratum) at the current position shown in FIG. It is decided.

Further, the backfill portion on the outer periphery of the casing 1 is provided with water shielding materials i ₁ and i ₂ (for example, bentonite) above the upper screen portion 2 position and between the upper screen portion 2 position and the lower screen portion 3 position, respectively. Etc., and clay-based materials such as resin-based waterstop materials.

That is, as described in the section of means for solving the problem, the present invention usually assumes a well having a depth of about 30 to 70 m or more, and an impermeable soil layer such as a viscous soil is interposed between them. The upper screen portion of the backfill portion on the outer periphery of the casing 1 is utilized not only in the case of sandwiching, but also by utilizing the fact that groundwater tends to infiltrate in the horizontal direction compared to the vertical direction due to slight soil differences even within the same formation. Groundwater to be pumped by filling water shielding materials i ₁ and i ₂ in the middle of the upper screen part 2 position and the lower screen part 3 position in accordance with the formation at the casing 1 installation position, respectively, It prevents the flow of groundwater to be returned more efficiently, and maintains high thermal efficiency.

In the present embodiment, the filling gravel g ₂ in the lower Saegimizuzai i _2, filled with a filling gravel g ₁ between Saegimizuzai i ₁ and water shield member i ₂ charge, Saegimizuzai i Filling sand s is filled above ₁ , but these can also be selectively used according to the geology of the ground where the casing 1 is installed.

DESCRIPTION OF SYMBOLS 1 ... Casing, 2 ... Upper screen part, 3 ... Lower screen part,
11 ... Interior pipe, 12 ... Water passage, 13 ... Small hole,
21 ... Upper lid, 22 ... Socket, 23 ... Connection port, 24 ... Connection flange, 25 ... Cable hole,
31 ... Lower packer, 32 ... Socket, 35 ... Cable hole, 36 ... Sealing material,
41 ... Upper pumping pipe, 42 ... Submersible pump,
51 ... Lower pumping pipe, 52 ... Submersible pump,
61 ... Upper return hole,
71 ... Lower return water hole,
81 ... Return pipe,
s ... filled sand,
g ₁ , g ₂ ... filled gravel,
i ₁ , i ₂ ... water shielding material

Claims (6)

  An upper screen and a lower screen for allowing groundwater to enter and exit from the ground are provided in a casing that is installed in the ground and backfills the outer periphery to form a well for pumping and returning water. In the groundwater-based heat exchange system that can be pumped up and returned to the ground with a single well, the backfill portion on the outer periphery of the casing is divided into an upper screen portion side and a lower screen portion side by a packer. By filling a water shielding material above the upper screen position and between the upper screen position and the lower screen position according to the formation at the casing installation position, the groundwater to be pumped is returned to the groundwater. The groundwater-based heat exchange system is characterized by preventing a short-circuit in the flow of groundwater.   By switching between a plurality of pumps, pumping water from the upper screen portion side in the casing, returning water from the lower screen portion side to the ground, pumping water from the lower screen portion side, and from the upper screen portion side 2. The groundwater-based heat exchange system according to claim 1, wherein the operation of returning water to the ground can be switched. Groundwater use heat exchange equipment used in the groundwater use heat exchange system according to claim 2,
A casing having an upper screen part and a lower screen part, which is installed in the ground and constitutes the well for pumping and returning water;
An inner pipe having a water passage portion arranged at a predetermined interval in the radial direction inside the casing and communicating with the upper screen portion of the casing;
An upper lid provided on an upper portion of the interior pipe;
A lower packer and a sealing material provided at a lower portion of the interior pipe and partitioning the inside of the casing into an upper screen portion side and a lower screen portion side;
A lower water pump is provided at the lower end, passes through the upper lid, and an upper water pumping pipe for pumping water from the interior pipe;
A lower water pump for pumping water from a lower part in the casing, including a submersible pump for pumping at the lower end, penetrating the upper lid and the lower packer,
An upper return water hole formed in the upper lid,
A lower return water hole formed in the lower packer;
A return water pipe penetrating the upper lid and connected to the lower return water hole;
A heat exchange facility using groundwater, comprising:   4. The groundwater-use heat exchange facility according to claim 3, wherein the water flow portion is formed by a large number of small holes or slits formed in a pipe wall of the interior pipe.   The upper lid constitutes an upper lid of the interior pipe and the casing, and a socket for connection is provided at a position of the upper pumping pipe, the lower pumping pipe, the upper return water hole, and the return water pipe. The groundwater-based heat exchange facility according to claim 3 or 4, wherein   The said lower packer comprises the lower cover of the said interior pipe | tube, and the socket for a connection is provided in the position of the said lower pumping pipe and the said lower return water hole. Or heat exchange equipment using groundwater according to 5.

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