KR100675257B1 - Heat exchanging apparatus for the geothermy heat pump system - Google Patents

Abstract

A heat exchanging apparatus for a geothermal heat pump system is provided to considerably reduce a possibility of a crack or hole generation by firmly fusing PE(Poly Ethylene) pipes. A heat exchanging apparatus for a geothermal heat pump system, a sleeve(200) is inserted inside of a pipe well drilled to contain ground water(W1). In the sleeve, a plurality of PE pipes are fused and coupled to the sleeve. A through hole(220) is formed on a lower part of the sleeve for ground water inflow. A weight pendulum(230) is installed on a lower end part of the sleeve. A unit pipe is lengthened by being made of a high elastic material to decrease number of coupling parts for reducing possibility of coupling defect generation. The PE pipes constituting the sleeve have an inner diameter of 100~150mm and a thickness of 5~20mm so as to be transported or to be stored in a shape of a coil. And, a weight of the bottom portion of the sleeve is formed on the sleeve as one body by burying a concrete at a predetermined length in the bottom portion of the sleeve.

Description

Ground exchanging apparatus for the geothermy heat pump system

1 is a view showing the structure of a conventional standing column well type underground heat exchanger.

Fig. 2 is a diagram showing the structure of the underground heat exchanger of the embodiment of the present invention.

3 and 4 are partially enlarged views of a sleeve illustrating a heat exchange process;

<Description of Symbols for Main Parts of Drawings>

100: rock bed 110: well

120: wellhead 130: manhole

140: menhole cover 200: sleeve

210: pump 220: through-hole

230: weight 300: heat exchanger

310: groundwater outflow pipe 320: groundwater return pipe

330: valve 340: pipe return pipe

350: groundwater use pipe 360: circulation pipe

W1: Groundwater W2: Circulating Water

H: geothermal

The present invention relates to a heat exchange structure that performs cooling and heating using ground water and geothermal heat as heat sources, and more specifically, a PVC pipe having a short length of a sleeve of an underground heat exchanger constituting a geothermal heat pump system, by using an adhesive or mechanical connection device. Underground heat exchange of geothermal heat pump system that is easier to install and reduces the possibility of groundwater leakage in the middle of sleeve by fusion and connection of relatively long polyethylene (PE) pipes It is about the flag.

The use of geothermal heat is the use of geothermal power generation to generate electricity by using high temperature heat in the ground, the direct use of geothermal power such as hot springs, and the geothermal heat pump equipped with a heat pump to perform cooling and heating using low temperature geothermal heat. It can be largely divided into uses. The use of geothermal heat through geothermal heat pump uses groundwater and geothermal heat as heating and cooling heat sources. In general, since geothermal heat is a stable heat source with little temperature change throughout the year, it is suitable for use in residential and commercial areas. It is actively underway. As a kind of underground use, a geothermal heat pump that is widely used recently uses relatively shallow geothermal heat, and forms a well of about 400 to 500m deep inside a well-developed rock bed and installs a heat exchanger inside the well. This is a technique for cooling and heating, and its structure has been presented in the registered Utility Model No. 0371813 filed by the present applicant.

Among them, the heat exchanger using a semi-open type, so-called standing column W1ell geothermal heat pump uses direct water heat exchange between the rock and the groundwater using the accumulated water inside the narrow and long wells. Compared to open heat exchangers or hermetic heat exchangers using vertically inserted U-shaped pipes, the diffusion is gradually expanding due to problems such as securing the installation space inside the well, installation cost, pollution, product life, maintenance of the well, etc. to be.

1 is a view showing the structure of a general standing column well type underground heat exchanger.

As shown in FIG. 1, the standing column well type heat exchanger circulates a fluid such as a refrigerant into a sleeve 200 embedded in a well 110 formed by drilling a rock layer, thereby cooling and heating by geothermal heat. In order to achieve this, the sleeve 200 generally uses a pipe made of polyvinyl chloride (PVC).

As the name implies, PVC contains chlorine, an ozone depleting substance, and it is recognized as an unfriendly environment due to the generation of dioxin in the manufacturing process. Therefore, PVC (polyethylene) and Likewise, it is being replaced with more environmentally friendly materials. Among PE pipes, HDPE (High Density Polyethylene) is widely used for water and sewage and gas pipes. Table 1 below compares HDPE and PVC.

designation HDPE (High Density Polyethylene) PVC (Polyvynil chloride) Chlorine Not included include Dioxin No occurrence Occurs (manufacturing process) Abrasion Strong Relatively strong Chemical reaction Strong Relatively strong Impact Strong Weak (especially at low temperatures) Joining Leak-free connection possible (fusion possible) Less leakage Density Low (0.95-0.99) High (1.43 on average) Flexibility Flexible (not broken) Rigid (broken) Strength Lower strength per volume than PVC High intensity per volume Flammability Resistant to combustion Weak to burn

As can be seen from Table 1, PVC pipe is limited in making its length long due to its weak elasticity and hard materials, and generally has a length of 4 to 6 m. Therefore, a sleeve is extended from the top of the well to the depth of 400 to 500 m. In order to construct, it is common to use a plurality of pipes connected by an adhesive. Therefore, the sleeve formed by connecting a plurality of PVC pipes using an adhesive or a mechanical connecting device as described above has about 100 joints, so that the work process is complicated and the sleeves may be damaged due to the failure of the adhesive part during installation or use of the sleeve. There is a fear that cracks or holes are generated in the middle to reduce the performance of the entire sleeve.

In addition, since the bonding portion is made using an adhesive, the adhesive portion is not strong, and when the inspection is necessary due to cracks or holes during installation or use, it is not possible to pull up the entire sleeve from the top of the well. There is a problem that inspection and maintenance are not easy.

The present invention is to solve the above problems, without using a sleeve embedded in the inside of the pipe connecting the PVC pipe having more than 100 joints, to have a length of 100 ~ 150m to have 3 to 4 joints It is aimed at reducing the number of joints by fusion welding the constructed PE (polyethylene) pipe.

In addition, since the bonding part is made of a fusion of the PE pipe itself, the bonding part is very solid, so when a problem such as cracks or holes occurs during installation or use, the whole sleeve is easily pulled up from the top of the well when the heat exchanger needs to be inspected. The objective is to facilitate the installation, inspection and repair of underground heat exchangers.

In addition, the lower end of the sleeve constitutes a weight made of concrete, etc. PE pipe lower in specific gravity than water naturally sinks to the lower part of the well to facilitate the installation of the sleeve.

In order to achieve the above object, the ground heat exchanger of the geothermal heat pump system according to the present invention in the ground heat exchanger of the air-conditioning system using geothermal energy, the ground heat exchanger is installed in the interior of the well drilled to ground water in the underground rock bed Comprising a sleeve that is made, the sleeve is a plurality of polyethylene (PE) pipe is fused and connected, the bottom is formed with a through-hole through which groundwater flows, the lower end is characterized in that the weight is configured.

In addition, the polyethylene (PE) pipe constituting the sleeve is characterized in that the inner diameter is 100 ~ 150mm, the thickness is 5 ~ 20mm to be stored and transported in the form of a coil.

In addition, the weight of the lower end of the sleeve is characterized in that the predetermined length of the lower end of the sleeve is embedded in concrete and made integral with the sleeve.

In addition, the sleeve is characterized in that the unit pipe of 100 ~ 150m length is fused, connected to the entire length of the sleeve.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a view showing the structure of the underground heat exchanger of the embodiment of the present invention, Figure 3 and Figure 4 is a partial enlarged view of the sleeve showing the heat exchange process.

As shown in Figure 2, the standing column well type underground heat exchanger used in the present invention is mainly applied to a well-developed area, and the groundwater (W1) in the ground by drilling the rock bed (100) 110 is formed and absorbs the heat of the rock constituting the well by using the groundwater (W1) accumulated in the inside of the well 110, or uses a method of storing heat in the rock. That is, the underground heat exchanger of the embodiment of the present invention is a well (110) obtained by drilling the rock layer 100, the sleeve 200 is installed over the floor from the top of the well 110, and embedded in the sleeve 200 It is configured to include a pump 210 for lifting the ground water (W1) accumulated in the well 110, the well 110 is preferably made of a narrow and long form of the inner diameter of 200mm, 400 ~ 500m in length.

In the case of the drill well 110 drilled as described above, except that the upper well is not the casing 110, the groundwater (W1) flowing in the upper or lower portion of the rock layer 100 inside the direct contact with the rock It is naturally held up, and can be opened and closed above, and a well head 120 for preventing contamination is provided. In addition, the manhole 130 is usually formed on the upper side of the well 110 to be drilled, and it is preferable to configure the manhole cover 140 that can be opened and closed above the manhole 130, and the groundwater W1 accumulated therein. The underground column heat exchanger using a standing column well may not be perforated exactly perpendicular to the surface of the well.

The sleeve 200 introduced into the well 110 has a unit pipe made of polyethylene (PE) material having a length of about 100 to 150 m and is fused so as to have 3 to 4 connection parts, and thus the depth of the pipe 200 is about 400 to 500 m deep. It is installed from the top of the well 110 to the bottom. The PE pipe can be stored and moved in the form of a coil even if the length of the conventional PVC pipe is made of a long elastic because of the material properties of high elasticity, compared to the fact that the PVC material was not possible to produce a length of more than 4 ~ 6m. It can be manufactured 10 times longer than a pipe. As described above, when the length of the unit pipe constituting the sleeve 200 is increased, the number of connection parts, that is, the joints (not shown) of the entire sleeve 200 is reduced, thereby reducing the possibility of poor bonding between the unit pipes. In addition, the conventional sleeve 200 is used to connect the PVC pipe with an adhesive or a mechanical connecting device, the sleeve 200 of the present invention is bonded to the PE pipe by fusion, so the joint is very solid and not fused It has a higher strength than the pipe portion of, and there is little possibility that holes or cracks will occur in the middle of the sleeve 200 during use. In addition, due to the nature of the material that is bent but not broken, the possibility of a failure in the middle of the sleeve 200 during the installation or maintenance of the heat exchanger is significantly lower than that of the PVC pipe.

The PE pipe has an inner diameter of 100 to 150 mm and a thickness of 5 to 20 mm, and more preferably, an inner diameter of 120 mm and a thickness of about 10 mm, depending on the size of the pipe well. Here, the PE pipe is manufactured about twice as thick as the conventional PVC pipe having a thickness of 5 to 6 mm, and limiting the thickness of the PE pipe is manufactured in the form of a coil when the thickness of the PE pipe is too thick. It is difficult to store and transport, and even if the thickness is too thin, it is difficult to maintain the pipe in the form of a coil, and the thermal cutoff between the groundwater W1 and the groundwater W1 after the heat exchange inside the sleeve 200 is appropriately performed. This is to prevent it from happening. That is, the thermal conductivity of the PVC pipe is k _PVC = 0.2 w / mk and the thermal conductivity of PE pipe is k _PE = 0.44 With w / mk, PE pipes have about twice the thermal conductivity of PVC pipes, so a sleeve made of PE pipes is about twice as large as conventional PVC pipes to achieve the same level of thermal performance as conventional PVC pipes. It will be made 10mm thick.

However, the specific gravity of the pipe made of a material of the PVC pipe on average 1.43 g / cm ³ as compared to much heavier than the water, the specific gravity (比重) is a pipe made of a PE material generally is about 0.95 ~ 0.97 Since it is lighter than water in g / cm ³ , it is difficult to flow into the well 110 where the groundwater (W1) is standing in the installation process, so that the weight 230 is formed at the lower portion of the sleeve 200. The weight 230 is generally made of a material that is heavier than water can be used, and can be configured using a variety of methods, such as mounting by hanging a hole in the lower end of the sleeve 200. In addition, it is preferable to be made of concrete integral type rather than metal, such as lead or iron, which is a concern of environmental pollution. As such, when the weight portion 230 is integrally formed by embedding a portion of the lower end portion of the sleeve 200 in concrete, a well having a narrow and long shape may be installed in the lower portion of the sleeve 200. Also suitable for

In addition, the sleeve 200 is composed of the weight 230 is the length of the tube 110 and the sleeve 200 in the well 110, the size and volume of the inner diameter, and the like, and the PE pipe, water, concrete 100 kg considering the specific gravity relationship It is desirable to have a weight of. To this end, in the embodiment of the present invention, the weight 200 is formed by embedding the lower end of the sleeve 200 in concrete at about 4 m.

Even if the weight 230 is formed on the lower portion of the sleeve 200 as described above, since the jointed portion in which the unit PE pipe is fused is very strong, even if the entire sleeve 200 is pulled up during the installation, inspection, or maintenance of the heat exchanger. The junction is not damaged. In addition, as the use period elapses after the installation of the underground heat exchanger, a small rock or the like gradually buried from the rock bed 100 in which the well 110 is drilled is buried to the bottom of the well 110, and the sleeve 200 naturally It is fixed to the bottom of the well 110 to perform the heat exchange function smoothly.

In addition, the standing column well heat exchanger of the underground heat exchanger is made in the bottom of the well 110, for this purpose, as shown in Figure 3, the lower side of the sleeve 200 is a myriad of holes for the inflow of groundwater Is formed. Therefore, the groundwater W1 accumulated in the inside of the well 110 is introduced into the sleeve 200 through the through hole 220, and is raised and circulated by the pump 210 installed in the sleeve 200. do.

As described above, the ground water W1 accumulated in the well 110 according to the operation of the pump 210 flows along each pipe to be described later, and supplies energy by heat exchange. The heat exchange in the well 110 is performed. 4 is directly made by contact between the groundwater W1 itself and the rock layer 100 having high thermal conductivity using the well 110, which is not casing except for the upper portion, as shown in FIG. That is, the pure thermal conductivity of the rock layer 100 itself in direct contact with the groundwater is k _ROCK = 3 w / mk, thermal conductivity k _GROUT of the part backfilled by the grouting process It is much higher than 0.4 ~ 0.8 w / mk, so the heat conduction effect is excellent, and the synergy effect of heat exchange rate and the heating and cooling efficiency are doubled. For example, the heat exchange process described above will be described in more detail. In the case where cooling is performed by the underground heat exchanger of the present invention, the groundwater H1 having high temperature in the upper part of the well 110 is in contact with the rock layer 100. When cooled to the bottom of the well 110 by heat exchange with the coolant, the cooled ground water (W1) is introduced into the through hole formed in the lower side of the sleeve 200 by the pump 210 inside the sleeve 200 The cooling is achieved by moving to the upper part.

The cooled ground water (W1) moved to the upper portion as described above flows along the groundwater outlet pipe (310) to the circulating water (W2) and heat conduction circulating inside the building in a heat exchanger (300) such as a plate heat exchanger installed in the building. After being heat-exchanged according to the ground water return pipe 320 is moved, and re-introduced into the inside of the well 110 through the well return pipe 340 in accordance with the operation of the valve 330 installed at the end, or ground water use pipe ( 350, groundwater can be reused for other purposes. The circulating water (W2) heat-exchanged in the heat exchanger (300) is introduced into the heat pump unit through the circulation pipe 360 to achieve a predetermined cooling effect, the wells 110 through the ground water use pipe (350) The ground water (W1) re-introduced into the is cooled again by repeating the heat exchange process in the same pipe well 110, and then flows to the heat exchanger (300) through the ground water outlet pipe (310). Then, the circulating water (W2) after performing the heating and cooling process in the building flows along the circulation pipe 360 and is again heat exchanged through the heat exchanger (300). In addition, some of the ground water (W1) introduced into the ground water use pipe 350 after the heat exchange process may be reused for various purposes through a separate auxiliary facility such as a hot water tank.

As described above, the cooling effect is achieved by circulating a fluid such as a coolant such as groundwater (W1) by heat exchange with geothermal heat, which is mainly performed in summer when the temperature of the ground is lower than that of the atmosphere. By providing the ground water (W1) of the temperature rise in the well 110 to the air conditioner (300) can be applied in the same way to the heating of buildings and the like by the circulation water (W2) flowing along the circulation pipe (360).

Here, a heat pump, a temperature sensor, etc. may be added as a separate component that achieves a cooling and heating effect by interworking with the heat exchanger 300. Since these components are unnecessary parts of the scope of the present invention, a description thereof will be provided. It will be omitted.

The present invention is not limited to the above-described embodiments, and technical ideas that can be modified and converted by those of ordinary skill in the art to which the present invention pertains without departing from the gist of the present invention also belong to the following claims. Should be seen.

According to the present invention of the above configuration, the present invention consists of only three to four joints compared to the conventional PVC pipe by using a PE pipe composed of a length of 100 ~ 150m not fused PVC sleeves embedded in the inside of the well Therefore, even during installation or use, the probability of a defect occurring at the joint is very low, and the possibility of reducing the performance of the entire heat exchanger is reduced.

In addition, since the joint part is made by fusion of the PE pipe itself, the bonding part is very hard, and thus the possibility of problems such as cracks or holes during use is significantly lower. In some cases, when the heat exchanger needs to be inspected, the entire sleeve at the top of the well Easily pull up the effect of easy to check and repair the ground heat exchanger.

Therefore, water accumulated in the well does not flow into the sleeve, but flows into the sleeve only at the bottom of the well, so that the flow path of the groundwater is constant, thereby maintaining the air-conditioning efficiency of the ground heat exchanger at an appropriate level.

In addition, by constructing a weight made of concrete or the like on the lower portion of the sleeve, the PE pipe having a specific gravity lower than water naturally sinks to the lower portion of the well, thereby making it easier to install the sleeve.

In addition, by performing the heating and cooling by using the geothermal heat pump, energy savings by the long-term use according to the saving of installation costs, maintenance costs and the life of the product, there is an effect of reducing the problem of environmental pollution by using environmentally friendly alternative energy heat source.

Claims (4)

In the underground heat exchanger of a cooling and heating system using geothermal energy, The underground heat exchanger is made of a sleeve which is installed in the interior of the well drilled so that the groundwater accumulated in the underground rock layer, The sleeve is a plurality of polyethylene (PE) pipes are fused and connected, groundwater is formed through the opening through the bottom side, the bottom of the ground heat exchanger of the geothermal heat pump system, characterized in that the weight is configured. The method of claim 1, Polyethylene (PE) pipe constituting the sleeve to be stored and transported in the form of a coil, An internal diameter of 100 ~ 150mm, a thickness of 5 ~ 20mm underground heat exchanger of geothermal heating and cooling system, characterized in that made. The method according to claim 1 or 2, The weight of the lower end of the sleeve underground geothermal heat exchanger of the geothermal heating and cooling system, characterized in that made in one piece with the sleeve by embedding the predetermined length of the lower end of the sleeve. The method of claim 3, The sleeve is a ground heat exchanger of geothermal air-conditioning system, characterized in that the unit pipe of 100 ~ 150m length is fused, connected to the entire length of the sleeve.

Images