DE102012013337A1 - Energy pile for geothermal energy purpose i.e. combined heating and cooling systems, has collector tube comprising section that includes another section that transitions and runs helically around former section of collector tube - Google Patents

Abstract

The pile (1) has a concrete pile (2) and a collector tube (3) that comprises a section (5) that runs from an upper end (4b) to a lower end (4a) of the concrete pile. An axial extent of the section is aligned in a straight line and is provided parallel to an axis of alignment of the concrete pile. The section of the collector tube comprises another section (6) that runs from the lower end to a ground level (GOK). The latter section transitions and runs helically around the former section of the collector tube. An independent claim is also included for an arrangement of energy piles.

Description

The invention relates to an energy pile for geothermal energy, in particular for combined heating and cooling systems, comprising a concrete pile and a collector tube, the collector tube having a first, extending from an upper end to a lower end of the concrete pile section, the axial extent of straight and paraxial aligned with the orientation of the concrete pile.

In modern building construction, boring piles are used to build a foundation for structural reasons in the case of poorly supporting subsoil. Insofar as collector pipes for near-surface geothermal energy use are integrated in these bored piles, this refers to energy piles. They work in principle like geothermal probes and can be used both for heating and for cooling, in particular in conjunction with a heat pump. The term "heat" is thus understood to mean the amount of energy available or work and can be at a high temperature or a low temperature level. The energy pile forms a first heat exchanger, which cooperates with a second heat exchanger located in the building to be heated or cooled. The amount of heat is transported by means of a fluid between the heat exchangers.

The main advantage of energy piles is that the costs for the construction of bored piles for static reasons are already spent, so that on the one hand no additional installation costs for a geothermal probe incurred and on the other hand larger Teufen in a range of about 6 m to 60 m for the Geothermal energy with a corresponding higher mean annual average temperature are available.

An energy pile is for example from the DE 602 00 183 T2 known. Here, a tubular pile made of concrete as a prefabricated component and its centric cavity at the lower end of the pile with a closure plate permanently closed. A supply line runs within the pile into the area of the closure plate. In an upper area, a drain pipe protrudes into the cavity. During operation, a fluid from the supply line flows into the cavity and rises within the pile until it can be withdrawn via the drain line. In practice, it has proven to be disadvantageous that the fluid is guided exclusively within the concrete body. On the one hand, the post must have a minimum wall thickness according to static specifications, which precludes effective heat conduction, on the other hand, the ready-made pile is introduced by ramming into the soil, which can lead to repeated damage to the pile. Since the fluid after leaving the inlet or outlet line is guided exclusively by the prefabricated concrete body of the pile, it comes in case of damage to the pile again and again to losses of the fluid.

Thus, the invention has the object to provide an energy pile, which ensures both a favorable heat transfer to the ground and a high operational availability.

The object is achieved according to the invention with an energy pile in which the first section of the collector tube merges at the lower end into a second section extending to the upper edge of the terrain, which runs helically around the first section. Due to the helical profile of the second section results in comparison to conventional energy piles significantly larger amount of fluid, which also allows a relatively large wetted surface a favorable heat transfer.

The energy pile usually extends to a depth of 6 m to 60 m, wherein the depth is determined by static specification for the necessary stability of the building located thereon.

The helical course of the second section represents a helix, screw, helix, cylindrical spiral or helix and forms a curve that winds around the mantle of an imaginary cylinder at a constant pitch. Accordingly, the second section also winds, spaced in the radial direction, about the first section of the collector tube. Preferably, in the axial direction per meter of the energy pile, the second section should make at least one complete turn in the circumferential direction of the bored pile.

The ready energy pile is preferably acted upon by the second portion of the fluid whose temperature approaches as it flows through the helical course in the direction of the lower portion of the energy pile to the temperature of the adjacent substrate. After reaching the lower section of the bored pile, the fluid in the first section rises again in the direction of the ground level. The rise of the heated to a higher temperature level fluid is supported by its density change, so that pump energy can be saved. The first and second sections can escape laterally or in the axial direction of the bored pile from this.

Advantageously, the first and second sections of the collector tube are cast in situ concrete, wherein the in-situ concrete rests directly on the surface of the first and second sections.

It has been found to be particularly favorable that the first and second sections of the collector tube are surrounded by a pile-reinforcement basket. The pole reinforcement cage absorbs tensile stresses occurring in the installed state and also serves as an assembly aid of the collector tube with its first and second sections. Both sections of the collector tube may be attached at discrete intervals, for example by wire or cable ties, to the pole-protecting basket. For this purpose, it is particularly advantageous if the first section extends eccentrically within the pile reinforcement basket and can be attached to this or to the second section.

When creating the energy pile a protective tube with an internal space is first introduced into the ground, used concentrically in the inner space of the pole reinforcement basket with the collector tube mounted therein, in-situ concrete introduced into the protective tube and gradually progressively extracted the protective tube with progressing concreting progress. In operational condition, the mountains on the concrete cast with in-situ concrete pile. Preferably, the pile preservation basket is encased on all sides by in-situ concrete.

The pole-sparing cage should be inserted in a larger diameter bore so that no ramming or other procedures are necessary that require compressive forces on the pole-sparing cage.

Conveniently, the larger diameter bore is aligned approximately perpendicular. In addition to static specifications, this results in the advantage that the energy pile is perpendicular and an ascension of the heated fluid is supported particularly favorably, preferably by the first, vertical section. Due to the vertical orientation, it is possible to reach a greater depth, so that corresponding to the respective geothermal depth level, a higher average temperature of the soil is tapped.

Advantageously, the pole reinforcement cage extends over the entire axial length of the bore. To maximize the surface available for heat transfer, the collector tube should also extend with its first and second sections over the entire axial length of the bore.

According to a particularly advantageous embodiment, the collector tube is laid as an integral, one-piece line in the pile currency basket. As a result, laborious work on connecting pieces of individual segments can be avoided. In addition, connecting sleeves often present a weak point in terms of their tightness during operation.

Preferably, the collector tube is a PE tube. This can be taken in one piece from a roll and without installation of sleeves or fittings, which can significantly reduce the cost of the energy pile. If a particularly favorable efficiency is desired, the collector tube can also be made of stainless steel.

The large surface area resulting from the large axial length of the pile and the helical laying of the second section of the collector tube results in the synergistic effect that water can be applied to the collector tube as fluid. This considerably simplifies the licensing procedure for the operation of a facility for near-surface geothermal energy use. In addition, due to the operation with water only a minimum temperature of the fluid of about 2 ° C can be realized, so that there is no formation of a frost body around the energy pile.

The invention also extends to an arrangement of several energy piles, in which the first section of the collector tube is connected to an associated supply line after leaving the respective energy pile, in which a temperature measuring device or a flow meter is arranged before reaching a pump. The temperature measuring device or the flow rate counter supply a measured value for switching to another energy pile.

According to an advantageous embodiment, the supply lines are brought together in a collecting block, which acts on a main supply line. Among other things, the main supply line is connected to a pump and feeds one or more domestic heat exchangers.

Preferably, the main supply line terminates in a distribution block from which branch off to the first portion of a respective energy pile connecting lines.

Although in principle all energy piles are filled with the fluid, one or a few of them are only pressurized and activated for the power supply. The remaining energy piles regenerate and remain with the one inside Fluid stand. As the operating energy of the activated energy piles progresses, however, the surrounding subsurface approximately adopts the temperature of the fluid, so that, for example, in the winter heating mode, a cold jacket or cold horizon forms around the respective activated energy pile. This is noticeable on the basis of a changing flow temperature both in the respective supply line and in the main supply line.

In this case, the temperature measuring device may be arranged in the supply line or in the main supply line to identify a deviation of the actual temperature of a predetermined target temperature and trigger a switch to another energy pile.

The flow meter should be located in the supply line of the attached energy pile. Since the amount of fluid present in the energy pile is known, switching to another energy pile can be done, for example, after reaching that flow rate that is individually contained in the respective energy pile.

A selective activation of the respective connecting line is to take place by opening a blocking valve arranged in the distributor block or the respective connecting line as a function of a measured value of the temperature measuring device or of the flow rate counter. Thus, one or more used energy pile (s) is switched to one or more regenerated energy pile (s) that provide a maximum amount of heat.

For a better understanding, the invention will be explained for better understanding with reference to four figures. It show the:

1 : a cross section through an energy pile according to the invention

2 a plan view of the upper end of a concrete pile;

3 FIG. 2: shows a schematic circuit diagram of a system for near-surface geothermal energy use according to a first embodiment, and FIG

4 FIG. 2: shows a schematic circuit diagram of a system for near-surface geothermal energy use according to a second embodiment.

The 1 shows a cross section of an energy pile 1 in installed condition. The energy pile 1 is one with a pole rebar basket 8th reinforced concrete pile 2 formed and into a hole 9 introduced, leaving the concrete pile 2 down and around its peripheral surface with soil 22 contacted. The axial length L _{B of} the hole 9 corresponds approximately to the length of the concrete pile 2 ,

The pile reinforcement basket 8th is coaxial within its longitudinal direction within the concrete pile 2 aligned. Within the perimeter of the pole reinforcement cage 8th is an integrally integrally extending collector tube 3 , which has a first, vertical section 5 and a helical, coiled, second section 6 having. The collector tube 3 passes through the concrete pile 2 approximately over its entire axial length and is in the ready state completely with a fluid 10 , especially water, filled.

The concrete pile 2 of the energy pile 1 is inside the hole 9 up to the ground level GOK with in-situ concrete 7 poured out, so that in the installed state, the collector tube 3 and the postage basket 8th are arranged stationary to each other.

The second section 6 occurs above the ground level GOK in the concrete pile 1 and passes through this in the bore 8th starting from an upper end 4b with helical turns up to a lower end 4a , Due to the helical turns of the second section 6 is the fluid 10 a large volume with a likewise large surface of the collector tube 3 to disposal. The second section 6 of the collector tube 3 is point or line-like on the inner wall of the pile reinforcement basket 8th and is attached to this.

The second section 6 goes at the bottom 4a of the concrete pile 2 by bending the collector tube 6 in the first section 5 over, which runs uphill and directly back to the upper ground GOK. At an exit 11 of the first section 5 can the fluid 10 subtracted from.

The first paragraph 5 is also on the inner wall of the pile reinforcement cage 8th and / or at the second section 6 tethered. This leaves both sections 5 . 6 also during the placement of in-situ concrete 7 at their intended position.

In the 2 is the energy pole 1 in a plan view of the upper end 4b of the concrete pile 2 shown. This is particularly well the concentric arrangement of the concrete pile 2 and the pile reinforcement basket therein 8th clear. The exit 11 and the associated second section 6 are regarding the pole-rebuilding basket 8th arranged eccentrically and abut this point or line-like.

The 3 shows an arrangement of several energy piles 1 , which are connected to a facility for near-surface geothermal energy use. Each of the energy piles 1 is with the associated exit 11 to a supply line 12a . 12b . 12c . 12d connected. The fluid 10 (please refer 1 ) of the supply lines 12a . 12b . 12c . 12d will be in a collection block 16 merged and from there until reaching distribution block 18 , in a main supply line 17 passed through a building, not shown. The necessary pump energy is supplied by a pump 13 applied within the main supply line 17 is arranged.

For the transmission of the fluid temperature level to the room air of the building flows through the fluid from the main supply line 17 at least one home heat exchanger 21 , In the flow direction behind the house heat exchanger 21 is the distributor block 18 at which to the respective energy pile 1 running connecting lines 19a . 19b . 19c . 19d are connected. Each of the connecting cables 19a . 19b . 19c . 19d can via a check valve 20 be placed individually depressurized, so that in the associated energy pile 1 located fluid remains in this and the energy pile 1 is inactive. The check valve 20 can each be in the connecting line 19a . 19b . 19c . 19d arranged or in the distribution block 18 be integrated.

An essential feature of this arrangement relates to the individual control of each energy pile 1 over the respective shut-off valve 20 based on the temperature or amount of fluid in the associated supply line 12 , The temperature can be in any supply line 12 with a temperature measuring device 14 or alternatively the amount of fluid with a flow meter 15 be recorded.

The temperature measuring device 14 or the flow meter 15 are via a control line 23 with the shut-off valves 20 connected. For example, in heating mode, the temperature level inside the supply line should be 12a fall below a predetermined temperature level, the connecting line 19a at the corresponding check valve 20 closed, leaving the associated energy pole 1 can regenerate.

So that the system can continue to be provided with the required amount of heat, it will be replaced by one or more of the potentially previously closed connection lines 19b . 19c . 19d open.

As a control variable for opening or closing the check valves 20 In addition to the temperature level, the amount of fluid delivered can also be used. So it is possible to the computational content of an energy pile 1 to promote and by means of in the supply lines 12a . 12b . 12c . 12d located flow meter 15 to identify. If the fluid quantity of the energy pile 1 for example via the supply line 12a at unpressurized connection lines 19b . 19c . 19d has been promoted, can then connect to the connection 19b changed and the connection line 19a for the regeneration of the associated energy pile 1 getting closed.

The 4 shows a simplified arrangement in which instead of the individual temperature or flow rate of the fluid in the respective supply line 12a . 12b . 12c . 12d the mixing temperature of the fluid in the main supply line 17 by means of a built-in temperature measuring device 14 is detected. Once the from the temperature measuring device 14 measured temperature deviates from a predetermined target temperature is of the or previously activated energy piles 1 on the previously inactive energy piles 1 switched. Also in this embodiment, it is possible to use individual connection lines 19a . 19b . 19c . 19d to turn on or off.

LIST OF REFERENCE NUMBERS

1

energy pile

2

concrete pile

3

collector pipe

4a

lower end concrete pile

4b

Upper end concrete pile

5

first section

6

second part

7

situ concrete

8th

Pile reinforcement cage

9

drilling

10

Fluid, water

11

Exit second section

12a-d

supply line

13

pump

14

Temperature measuring device

15

Flow Meter

16

collection block

17

Main supply line

18

distribution block

19a-d

connecting line

20

check valve

21

House heat exchanger

22

soil

23

control line

GOK

ground level

L _B

axial length bore

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 60200183 T2 [0004]

Claims (15)

Energy pile ( 1 ) for the use of geothermal energy, in particular for combined heating and cooling installations, comprising a concrete pile ( 2 ) and a collector tube ( 3 ), wherein the collector tube has a first, from an upper end ( 4b ) to a lower end ( 4a ) of the concrete pile ( 2 ) extending section ( 5 ) whose axial extension is rectilinear and paraxial to the orientation of the concrete pile ( 2 ), characterized in that the first section ( 5 ) of the collector tube ( 3 ) at the lower end ( 4a ) into a second section running to the ground level (GOK) ( 6 ), which is helically around the first section ( 5 ) runs. Energy pile ( 1 ) according to claim 1, characterized in that the first and second sections ( 5 . 6 ) of the collector tube ( 3 ) in in-situ concrete ( 7 ) are poured. Energy pile ( 1 ) according to claim 1 or 2, characterized in that the first and second sections ( 5 . 6 ) of the collector tube ( 3 ) from a pile-reinforcement basket ( 8th ) are surrounded. Energy pile ( 1 ) according to claim 3, characterized in that the pile preservation basket ( 8th ) on all sides of in-situ concrete ( 7 ) is poured around. Energy pile ( 1 ) according to claim 3 or 4, characterized in that the pile reinforcement cage ( 8th ) into a larger diameter bore ( 9 ) is used. Energy pile ( 1 ) According to claim 5, characterized in that the larger diameter bore ( 9 ) is aligned approximately vertically. Energy pile ( 1 ) according to claim 5 or 6, characterized in that the pile reinforcement cage ( 8th ) over the entire axial length (L _B ) of the bore ( 9 ). Energy pile ( 1 ) according to one of claims 3 to 7, characterized in that the collector tube ( 3 ) as an integral, one-piece conduit in the pile preservation basket ( 8th ). Energy pile ( 1 ) according to one of claims 1 to 8, characterized in that the collector tube ( 3 ) is a PE pipe. Energy pile ( 1 ) according to one of claims 1 to 9, characterized in that collector tube ( 3 ) is charged with water. Energy pile ( 1 ) according to one of claims 3 to 10, characterized in that the collector tube ( 3 ) on the pile reinforcement cage ( 8th ) is attached. Arrangement of several energy piles ( 1 ) according to one of claims 1 to 11, characterized in that the first section ( 5 ) of the collector tube ( 3 ) after leaving ( 11 ) from the respective energy pile ( 1 ) to an associated supply line ( 12a . 12b . 12c . 12d ) is connected before reaching a pump ( 13 ) a temperature measuring device ( 14 ) or a flow meter ( 15 ) is arranged. Arrangement according to claim 12, characterized in that the supply lines ( 12a . 12b . 12c . 12d ) in a collecting block ( 16 ) to which a main supply line ( 17 ) attacks. Arrangement according to claim 13, characterized in that the main supply line ( 17 ) in a distribution block ( 18 ), from which to the first section ( 5 ) of a respective energy pile ( 1 ) connecting lines ( 19a . 19b . 19c . 19d ) branch off. Arrangement according to claim 14, characterized in that a selective activation of the respective connecting line ( 19a . 19b . 19c . 19d ) based on a measured value of the temperature measuring device ( 14 ) or the flow rate counter ( 15 ) he follows.

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