DE202009000995U1 - Combined heat storage system - Google Patents

Abstract

Combined heat storage system consisting of at least one tank (1) which is arranged in the ground (15), a heat pump (2) which is connected to at least one heat exchanger (3), wherein the heat exchanger (3) in a tank (1) is arranged a pump (14) for a well (5), which is connected to the tank (1) or the tanks, a tank pump (13), which is arranged in the tank (1), at least one overflow (7) in the lower region of the tank (1) is arranged and a controller (12).

Description

The The invention relates to a combination heat storage system and a method for storing and using geothermal energy by means of a combined heat storage system. The invention lies in the field of the use of alternative energies as an energy source especially of buildings.

When using geothermal heat pump systems, it is state of the art to install in the soil a pipe system, which is traversed by a water-frost protection mixture (brine), as already for example in the DE 8010743 is described. The brine absorbs the heat energy from the soil, transports it to the heat pump and releases it there. Depending on the extraction capacity of the heat pump, the pipe system must have an appropriate length, as the withdrawal rate per meter of pipe is limited.

These piping systems are called collectors (eg flat plate collectors, spiral collectors, etc.) or probes (deep probes). Such a heat exchanger describes, for example, the DE 3149636 , The use of collector systems or probes mainly uses the natural energy flow in soil and rock as a heat source. The temperatures of the system sink in the heating period up to -4 ° C. The space requirement of collector systems is not insignificant. Deep probes are complex and generally subject to approval. In water protection areas, collector systems and deep probes are generally prohibited.

at the use of groundwater as a heat source for a heat pump system is state of the art, by means of a well pump to promote the groundwater, through the Heat exchanger (evaporator) to lead the heat pump and then through a gulp again the Supply groundwater layer. As a variant is known that an additional heat exchanger the energy from the groundwater to a brine circuit passes, which flows through the evaporator of the heat pump.

at This technique requires that the well pump simultaneously be in operation with the heat pump and the required Minimum flow through the evaporator or additional Heat exchanger must ensure. This means by the high performance and the associated increased power consumption the well pump a worse annual work count of the complete Investment.

Of the Evaporator or additional heat exchanger is in direct contact with the groundwater and there is a risk that due to poor water quality or dirt particles frequent and expensive maintenance is required or even the destruction of the material threatens. Should the Evaporators are destroyed, this usually means one total economic loss of the heat pump. The same applies to installations where the groundwater directly into the Evaporator is led and it by a wrong operation or a technical defect comes to a freezing of the water.

When Another possibility is known collector systems, the as earth collector systems in the groundwater leading layer to be built in. There are usually spiral collectors PE or stainless steel corrugated pipe installed. This variant is however with reasonable effort only at shallow groundwater layers possible. In addition, several collectors are required the one correspondingly large area on the property claim. Due to the high number of collectors also increases the amount of brine in the system. But these are usually contains antifreeze, in case of leakage the danger of having a larger amount of this remedy can get directly into the groundwater.

The DE 20203712 U1 describes a heat pump having a hot water tank, in which a heat exchanger is arranged, and which has a further heat exchanger that does not use a terrestrial heat source. However, can now be used directly adjacent to the hot water storage geothermal, which is quickly exhausted, so that without significant increase in the hot water tank, the geothermal energy is only insufficiently used.

In the DE 20 2006 005 592 U1 a water storage is described in combination with a heat pump, wherein the water storage consists of buried in the ground underground tanks having embedded in the wall of the water storage heat exchanger coils. A maintenance and installation of these water tanks is expensive. It can not be used after the installation changes or errors can not be fixed. Also, existing or inexpensive water storage can not be used.

The The object of the invention is to overcome the disadvantages of Prior art to avoid or minimize and optimized To provide plant as well as an efficient process that is simple and is inexpensive to operate.

The Task is by specifying a combined heat storage system according to claim 1 and a method of use of geothermal energy by means of a combination heat storage system solved according to claim 5. The dependent claims 2 to 4 and 6 to 11 give further advantageous embodiments to the invention.

The inventive combination heat storage system consists of at least one tank located in the ground, a heat pump with at least one heat exchanger is connected, wherein the heat exchanger arranged in a tank is a pump for a well that is connected to the tank or the Tanks connected to a tank pump, which is located in the tank is, at least one overflow, in the lower area the tank is arranged and a controller.

The Combined heat storage system serves optimally as a heat exchanger process for the use of groundwater as an energy source for a Heat pump system and additional extraction of further geothermal energy. Preferably, there is the easy way the additional use of rainwater heat, Heat from exhaust air heat recovery, Solar thermal, sewage heat, surface water heat, See, sea and river water heat to optimize the entire Heat pump system by minimizing the required Required space, the required well output and the used Pumping, so as to achieve an improved annual work rate and to ensure easy and inexpensive maintenance of the plant.

A advantageous embodiment of the combination heat storage system provides that the heat exchanger is designed as a spiral tube is and preferably made of stainless steel. The stainless steel spiral tube heat exchanger has a large transfer area, so that the tube length used is much lower than with a smooth pipe or a ground collector. This allows the Amount of antifreeze in the brine be kept low. The risk of pollution and reduced flow as in a plate heat exchanger does not exist. The maintenance and Cleaning the system is straightforward.

A preferred variant of the invention is characterized in that the tank is designed as a rainwater tank or cistern.

Especially advantageous is the further or reuse of purified oil and / or gas tanks.

The Combined heat storage system is advantageously used as a heat exchanger method for the use of groundwater as an energy source for a Heat pump system with additional extraction of Geothermal and the further possibility of use of rainwater heat, heat from exhaust air heat recovery, solar thermal, Sewage heat, surface water heat, See, sea and river water heat to optimize the control the entire heat pump system by minimizing the required Required space, the required well output and the used Pumping, so as to achieve an improved annual work rate and a simple and inexpensive maintenance of the plant sure.

The Advantages of the combined heat storage system compared a ground collector is in the smaller footprint, the usability also in water conservation areas, the utilization of additional heat of groundwater and additional heat from rainwater, solar, Exhaust air, waters. It provides higher input temperatures for the heat pump and has a higher one Annual work figure.

Across from a groundwater heat pump has the combination heat storage system Advantages, as a significantly lower groundwater production required, allows operation without separation exchanger is achieved and easy maintenance and high reliability becomes. Furthermore, additional heat from the soil as well from rainwater, solar, exhaust air, and waters usable. Again, the higher inlet temperatures are for Heat pump and the higher annual work rate the system advantageous.

embodiments The invention will be explained below with reference to the drawings.

It shows 1 a schematic diagram of a heat pump system with a combination heat storage system. 2 shows an exemplary plant schematic of a preferred heat pump system. 3 shows an example of the arrangement of a combination heat storage system according to the invention.

In 1 becomes a tank 1 introduced into the soil. Also can be used already existing rainwater tanks, cisterns, purified oil or gas tanks and purified wastewater tanks.

The use of a tank 1 in the soil 15 allowed by the high storage capacity of the water that the flow rate and power of the well pump 5 can be chosen smaller. Furthermore, geothermal heat from the surrounding soil is used to regenerate the water temperature. In summer, the system can be operated in favorable weather conditions without the addition of groundwater. The brine-water or water-water heat pump 2 is by brine pipe 4 to a stainless steel spiral tube heat exchanger 3 connected.

The stainless steel spiral tube heat exchanger 3 has a large transfer surface, so that the tube length used is much lower than with a smooth tube or a ground collector. As a result, the amount of antifreeze in the brine can be kept low.

The risk of contamination and reduced flow as in a plate heat exchanger does not exist. The maintenance and cleaning of the system can be carried out easily and without major installation effort, since the stainless steel spiral tube heat exchanger 3 in one piece through the inspection shaft 17 can be removed.

The groundwater supply of the tank 1 takes place through a groundwater well 5 with pump 14 , The enema 6 is preferably designed so that the water is swirled.

The well pump 14 is only put into operation when a controller 12 a brine outlet temperature below an adjustable value and the operation of the heat pump 2 z. B. recognizes by the operation of the brine pump. The tank pump 13 is also soltemperaturgesteuert and ensures a temperature compensation in the tank 1 by mixing the warmer and colder areas of the water.

By the soletemperaturabhängige control of the well and tank pump 14 . 13 the operating time is significantly reduced and the annual work rate of the system increases.

The excess water in the tank 1 gets through an overflow 7 dissipated. This is done so that the bottom of the tank 1 standing cooler water in the infiltration 8th can drain away.

The infiltration 8th will be close to the surface through seepage blocks or tunnels, trenches or pipe infiltration. Also, swallowing wells are possible. A surface drainage into a stream or lake is also possible. The execution depends on the official regulations and possible other water discharges except the groundwater.

In this example, rainwater from the roof drainage 9 also in the tank 1 initiated. Also conceivable but not shown are discharges from the surface drainage or wastewater, which then but are to be carried out with special attention to infiltration.

By the introduction of seawater, river water, etc., not shown, many free natural heat sources are available, which help the operating times for the well pump 14 to further reduce and increase the annual work rate of the plant.

The brine can - as exemplified - additionally by a system of exhaust air heat recovery 10 or a solar collector 11 be enriched with energy. This energy will then be in the tank 1 cached and is the heat pump 2 again available. Exhaust air heat and solar heat offer further possibilities to use free natural heat and to increase the annual work rate of the plant.

2 shows an exemplary plant schematic of a preferred heat pump system.

In This embodiment is a typical Inventory (year of construction ca. 1900) with a radiator system with flow temperature 50 ° C, a water heating for 4 people. The heat energy requirement of the building is 56199 KWh / a, the heating power requirement is about 24 KW.

The exemplary heat pump system 2 consists of a high temperature heat pump (R134a) with hot gas heat exchanger, a heating capacity at B0 / W35 25.2 KW, a buffer tank 18 (500 liters) for heating and a buffer tank 300 liters with domestic water hygiene system (BHS) for process water preparation in a water-heater process.

• 1 Tank: 2 × Regenwassertank 2500 Liter
• 2 Wärmepumpe: Hochtemperaturwärmepumpe (R134a); Heizleistung bei B0/W35 25,2 KW
• 3 Wärmetauscher: 2 × Edelstahl-Spiralrohr DN25, Rohrlänge 50 m
• 4 Soleleitung: PE-Rohr DN32, Länge 2 × 20 m
• 5 Grundwasserbrunnen Tiefe 20 m mit Pumpe 14: Leistung 0,37 KW
• 6 Grundwassereinlauf
• 7 Überlauf
• 8 Oberflächennahe Versickerung durch Sickertunnel
• 9 Einleitung Dachentwässerung ca. 150 m² Dachfläche
• 12 Steuerung mit zwei Temperaturwächtern
• 13 Tankpumpe: 2 × Tauchpumpen, Leistung pro Pumpe 0,22 KW

3 shows an arrangement of a combination heat storage system according to the invention. This is done as follows:

• 1 Tank: 2 × rainwater tank 2500 liters
• 2 Heat pump: high temperature heat pump (R134a); Heating power at B0 / W35 25.2 KW
• 3 Heat exchanger: 2 × stainless steel spiral pipe DN25, pipe length 50 m
• 4 Brine pipe: PE pipe DN32, length 2 × 20 m
• 5 Groundwater well depth 20 m with pump 14 : Power 0.37 KW
• 6 Groundwater inflow
• 7 overflow
• 8th Near-surface seepage through seepage tunnel
• 9 Introduction roof drainage approx. 150 m ² roof area
• 12 Control with two temperature monitors
• 13 Tank pump: 2 × submersible pumps, power per pump 0.22 KW

This combination heat storage system works as follows:
Detects the controller 12 the heat pump 2 For example, by a temperature measuring device in the building to be heated a (Nach-) heating demand for the building, together with the compressor of the heat pump 2 started the integrated brine pump. Through the brine pipeline 4 Preferably, a water-antifreeze mixture is pumped through the heat exchanger 3 the water in the tanks 1 Heat energy withdraws. The recovered heat energy is in the heat pump 2 taken again from the brine circuit.

The control 12 is activated during operation of the heat pump and monitors the brine temperature.

The brine temperature drops as a result of the energy withdrawal from the tanks 1 below an adjustable value, the tank pumps become 13 started. The tank pumps 13 provide a wash around the water in the tanks 1 and thus convey the warmer water parts from the edge areas to the heat exchanger 3 , In this way, both from the surrounding soil 15 , as well as recovered from the rainwater heat energy heat exchangers 3 fed.

Nevertheless, the brine temperature drops due to the consumed and not enough after flowing heat energy in the tanks 1 Next, the well pump is activated via a second adjustable value 14 started. The well pump 14 promotes groundwater at a temperature of about + 7 ° C over the enemas 6 in the tanks 1 , To maintain a constant water level in the tanks 1 To ensure, cold water is released from the bottom of the tanks 1 by overflows 7 dissipated and through a system of seepage tunnels 8th in the soil 15 issued.

As soon as the brine temperature rises again to your respective set values, both the well and the tank pumps become 14 . 13 again through the controller 12 switched off.

The same applies to switching off the heat pump 2 , In this way it is achieved that the well and tank pumps 14 . 13 only in real need in operation. During the downtime of the heat pump, the temperature level of the water in the tanks may increase 1 through the soil 15 and infiltrating rainwater 9 regenerate.

The annual operating figures of the entire system with combination heat storage system are as follows: • Operating hours of the heat pump according to design: 2000 h / a • Heat energy released: 56199 KWh / a • Current consumption of the heat pump (including circulating pumps): 15521 KWh / a • Water temperature in the tank Summer: + 10 ° C • water temperature in the tank winter: + 7 ° C • Operating hours of the well pump: 800 h / a • Flow rate groundwater: 2900 m ³ / a • Current consumption of the well pump: 296 KWh / a • Operating hours of the tank pumps: every 1400 h / a • Power consumption of the tank pumps: together 616 KWh / a • Total power consumption of heat pump and pumps: 16433 KWh / a • Annual work rate of the plant: 3.42

1

tank

2

heat pump

3

Stainless steel spiral tube heat exchanger

4

brine line

5

Groundwater well with pump ( 14 )

6

Groundwater inflow

7

overflow

8th

infiltration

9

roof drainage

10

air conditioning with heat recovery

11

solar collector

12

control

13

tank pump

14

well pump

15

soil

16

building

17

inspection chamber

18

buffer memory

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 8010743 [0002]
• - DE 3149636 [0003]
• - DE 20203712 U1 [0008]
• - DE 202006005592 U1 [0009]

Claims (4)

Combined heat storage system consisting of at least one tank ( 1 ), in the soil ( 15 ), a heat pump ( 2 ) with at least one heat exchanger ( 3 ), the heat exchanger ( 3 ) in a tank ( 1 ), a pump ( 14 ) for a well ( 5 ) with the tank ( 1 ) or the tanks is connected to a tank pump ( 13 ) in the tank ( 1 ), at least one overflow ( 7 ) located in the lower part of the tank ( 1 ) and a controller ( 12 ). Combined heat storage system according to claim 1, characterized in that the heat exchanger ( 3 ) Is designed as a spiral tube and is preferably made of stainless steel. Combined heat storage system according to one of the preceding claims, characterized in that the tank ( 1 ) is designed as a rainwater tank or cistern. Combined heat storage system according to one of the preceding claims, characterized in that as tank ( 1 ) are arranged cleaned oil and / or gas tanks.