from geological formations

The subject of the invention is a method of continuous collection of thermal energy from geological formations in which heat is collected in the operational unit and a system for implementing this method.

Earth's energy is accumulated in our globe and almost evenly dispersed and generated by nuclear reactions in the Earth's core. For the purposes of this description, the energy stored in the Earth is called geo-plutonic energy.

The temperature produced in the core of the earth is about 6000-7000 °C. The heat moves towards the surface of the globe.

Previous attempts to recover this geo-plutonic energy have been very limited due to the tremendous difficulties associated with drilling and the need to use very expensive, special types of steel, to strengthen the components of the system for obtaining heat from wells.

Wells for extracting minerals, e.g. in the form of oil and gas, carried out in a traditional way cannot be used to obtain geo-plutonic energy, because the desirable characteristics of such wells are completely different from those necessary for efficient heat energy collection. The extraction of oil and gas aims at increasing the porosity and obtaining cracks in order to effectively discharge oil and gas from the geological formation. Obtaining geo-plutonic energy requires compactness and reduced permeability in order to increase the heat transfer capacity. Effective heat collection requires the development of a suitable system, specially adapted for this purpose. US 8,020,382 discloses a closed-loop system for extracting heat from geological formations. Heat recovery from geological formations is carried out using many horizontal rows of boreholes, so-called Jet-Stinger, coming out radially from the central shaft. The heat exchange takes place by means of heat exchangers placed in the final parts of the boreholes or by heat transfer through the walls of the boreholes.

U.S. Pat. No. 8,201,409 discloses a closed-loop operated dry rock heat recovery system utilizing a heat recovery fluid, wherein the fluid remains in the liquid state flowing from the earth's surface in an annular supply line to the final heat exchanger. The heat recovery fluid on the final heat exchanger partially evaporates as a result of local indirect heat transfer from the geological formation, creating a two-phase fluid or vapor stream flowing out from the final section of the heat exchanger to the axial return flow conduit.

The solutions disclosed in these publications do not provide :

1. The maximum use of the thermal field.

2. The technology of very deep drilling in a hot formation that provides protection against gas and steam eruptions.

3. The technology of sealing cracked rocks in formations with high temperatures ensuring adequate heat extraction.

In order to meet the above-mentioned assumptions, a comprehensive development of a catalogue of solutions and technologies suitable for obtaining geo-plutonic energy is required.

The aim of the invention is to develop a system for obtaining geo-plutonic energy with maximum efficiency, enabling construction of installations for automatic, continuous and linear generation of energy.

This objective has been implemented in a way and in a system that can be defined jointly as an ACEEESS (Alternating Cyclically Equilibrated Earth Energy's Subjugating System). The installation for carrying out the method and system according to the invention may be located on the surface of the earth or on the bottom of a reservoir or watercourse, e.g. a river, lake or sea .

The essence of the invention is a method of continuous extraction of thermal energy from geological formations, in which the heat is received in an operational unit containing a heat-receiving system, via a heat-receiving medium flowing in at least two deep-running wells in which

- the regeneration time of each well is determined,

- the distance between wells is determined,

- a pre-set temperature drop activating the flow of the heat-receiving medium in each of the well is determined,

the flow of the heat-receiving medium in the first well is activated,

- the flow in the first well is deactivated at a given temperature drop in the heat-receiving medium for a period equal to the determined regeneration time of the first well and the flow of the heat-receiving medium in the second well is activated in advance or simultaneously.

- the flow in the second well is deactivated at a pre-set temperature drop in the heat-receiving medium for a period equal to the determined regeneration time of the second well and the flow of the heat-receiving medium in the first or second well is activated in advance or simultaneously depending on whether the designated time for regeneration of the first well has already passed.

Preferably, the operational unit comprises two wells and the time for regeneration of the first well is shorter or equal to the time of heat collection from the second well.

Preferably, the heat is taken from a plurality of operational units located in a row or according to another geometric pattern.

Preferably, the distance between the operational units shall not exceed 10 m.

Preferably, the heat-receiving medium flows through the well in a conduit that forms a closed circuit.

Preferably, the heat-receiving medium flows through a well in the conduit which is insulated from the outside out of the section designed for heat exchange.

Preferably, the section designed for heat exchange comprises a heat exchanger.

Preferably, the heat-receiving medium flows through the conduit built from two concentric pipes between which a controlled vacuum chamber is located.

Preferably, the wells are "Jet-Stinger" type wells.

Preferably, the temperature drop that deactivates the flow of the heat-receiving medium is 2-5 °C.

More preferably, the temperature drop that deactivates the flow of the heat-receiving medium is 1 °C.

Preferably, no more than 4-5% of the heat resources gathered around the well are collected.

Preferably, the heat-receiving system generates electric current . Preferably, the heat-receiving system forms the circuit of the turbogenerator set.

Preferably, the heat is taken from a depth of 600-10000 m.

The essence of the invention is also a system for continuous heat recovery from geological formations comprising at least one operational unit comprising at least two wells extending into the earth and located at a designated distance from each other, which comprise the conduits connected to the heat-receiving system, with which the means forcing the flow of the heat- receiving medium in the circuit containing temperature sensors are connected, wherein the temperature sensors are connected to the means forcing the flow via the control unit.

Preferably, the operational unit comprises two wells.

Preferably, the distance between the operational units does not exceed 10 m.

Preferably, the system according to the invention comprises a plurality of operational units located in a row or according to another geometric pattern.

Preferably, the conduits are insulated from the environment outside of the section designed for heat exchange.

Preferably, the section designed for heat exchange comprises a heat exchanger.

Preferably, the conduit section insulated from the environment is built from two concentric pipes between which a controlled vacuum chamber is located.

Preferably, the wells are "Jet-Stinger" type wells.

Preferably, alternately operating pumps are used as flow forcing components .

Preferably, the heat-receiving system is connected to a system converting thermal energy into electric current. Preferably, the system converting thermal energy into electric current is a condenser containing circuit of a turbogenerator driving factor, connected to the control unit and to the power grid.

Preferably, the wells have a depth of 600-10000 m.

The system according to the invention is an open system for draining and acquiring earth energy from hot/warm underground or surface water and/or hot/warm water vapor inside geological formations, which is achieved by a sustainable system of long- term thermal efficiency, stable heat conversion for heating, cooling, generation of electricity and in general transformation into exogenous power systems.

The main application of the invention is to generate all forms of energy in order to sustain and utilize the controlled energy of the Earth with an exergy system to discover and exploit minerals from geological formations, marine and oceanic waters, lakes and rivers and for the benefit of the human population from small power units, in any way distributed and located mainly among small factories, cities, municipalities, villages and so on. One of the main goals is to supply energy and mechanical forces to the environment without pollution, gas eruptions and groundwater devastation.

The method and system of the invention in the embodiments are shown in the drawing, in which:

Fig. 1 is a schematic representation of a system according to the invention; Fig. 2 schematically shows an operational unit comprising two wells connected to a generator generating electricity in the form of a circuit with a turbogenerator;

Fig. 3 shows a schematic representation of the operational unit row during the work cycle;

Fig. 4 schematically shows the arrangement of the ground components of the installation in a plan view; and

Fig. 5 is a graph of temperature dependence from the operation time of an operational unit comprising two wells for acquiring thermal energy compared to the prior art system.

As shown in the embodiment of fig. 1, a system for continuous heat recovery from the geological formations according to the invention comprises at least one operational unit 1 comprising at least two wells 2, 3 extending into the earth and located at a designated distance 16 from each other in which there are conduits 5 connected to the heat-receiving system 4, with which a flow-inducing means 6 are connected causing the flow of heat-receiving medium 7 in the circuit 15 containing temperature sensors 8, wherein the temperature sensors 8 are connected to the flow-inducing means 6 through the control unit 9. The heat-receiving system 4 is connected to an electric current generating system 10 converting thermal energy into electric current.

Heat, in the system according to the invention, can be received via the heat-receiving medium 7 flowing in the wells 2, 3. The heat-receiving means 7 can be, for example, demineralized water, mineral waters, various liquid hydrocarbons, ammonia and other so-called heating/cooling fluids. These liquid carriers can be a closed recirculation stream or an open recirculation stream with a condensing system. In order to activate the system according to the invention, the regeneration time of each well 2, 3 is determined, the distance 16 between the wells 2, 3 is determined and a predetermined temperature drop is determined activating the flow of the heat-receiving medium 7 in each of the wells 2 and 3.

Then, the flow of the heat-receiving medium 7 is activated in the first well 2 until a predetermined temperature drop of the heat-receiving medium 7 is reached, wherein the temperature is measured by the temperature sensors 8, and the flow-inducing means 6 are controlled by the control unit 9 based on signals from the temperature sensors 8.

At a given temperature drop in the heat-receiving medium 7, the flow in the first well 2 is deactivated for a period equal to the determined regeneration time of the first well 2 and in advance or at the same time the flow of the heat-receiving medium 7 in the second well 3 is activated.

Next, the flow in the second well 3 is deactivated at a predefined temperature decrease of the heat-receiving medium 7 for a period equal to the determined regeneration time of the second well 3 and in advance or at the same time the flow of the heat-receiving medium 7 is activated in the first 2 or next well not shown in the drawing depending on whether the determined recovery time of the first well 2 has already expired.

A method for the continuous extraction of thermal energy from the geological formations according to the invention was carried out in the exemplary installation depicted in fig. 2 with two wells 2 and 3, the so-called tandem. Before commencing the execution of the actual wells 2 and 3, the test boreholes were executed (not shown) . On the basis of the measurements carried out, the recovery time for each well 2, 3 and the distance 16 between the wells 2 and 3 were determined. Then the wells 2 and 3 were executed containing heat exchangers 17 and a ground installation was built comprising a heat-receiving medium circuit 15 including the conduits 5, two pumps 6a and temperature sensors 8. The heat-receiving medium circuit 15 is designed to exchange heat with the circuit of the turbogenerator driving medium 14 in the heat-receiving system 4. The control unit 9 is connected to temperature sensors 8 and pumps and then programmed so that the temperature drop of 5 °C in the well 2 circuit stop the pump 6a forcing the flow in this circuit and at the same time start the pump 6a forcing circulation in the well 3 circuit. The assumed well 2 regeneration time was equal to the heat collection time from well 3. The flow of the heat-receiving medium 7 in the well 2 was activated. The heat-receiving medium has reached a temperature of 350°C. The heat was received in the heat-receiving system 4, which caused the temperature to rise and evaporation of the driving medium of the turbogenerator 12 in the circuit 14, which condensed in the condenser 11. Turbogenerator 12 transmitted electric power to the power grid 13 in a stable and continuous manner. When the temperature of the heat-receiving medium 7 dropped by 5 °C, the control unit 9 stopped the pump 6a in the circuit of the well 2 and started the pump 6a in the well 3 circuit. When the temperature dropped by 5°C in the well 3 circuit, the control unit 9 stopped the pump 6a in the well 3 circuit and at the same time started the pump 6a in the well 2 circuit closing the cycle of obtaining the geo- plutonic energy. The tested system worked continuously, generating stable eclectic energy.

As shown in the preferred embodiment in Fig. 2, the system according to the invention may comprise two wells, 2 and 3, the so-called tandem. In this case, the regeneration time of the first well 2 is shorter or equal to the time the heat is collected from the second well 3. The components forcing the flow of the heat-receiving medium 7 in the circuit 15 are the alternately working pumps 6a activated by the control unit 9 processing the signals from the temperature sensors 8. The wells 2, 3, in the section designed for heat exchange comprise heat exchangers 17 connected to the control unit 9. Fig. 2 shows the layout during operation. Arrows indicate the flow direction of the heat-receiving medium 7, and corrugated lines 18 schematically represent the thermal field system in the geological formation. The well 2 is in the process of regeneration, and heat energy is collected from the well 3. One of the wells contains a heat exchanger 17 that is not shown in the drawing in the remaining wells. The heat-receiving system 4 is formed by a circuit 14 of the driving medium with a condenser 11, and a turbogenerator 12 connected to the power grid 13.

Preferably, the system according to the invention comprises a plurality of operational units arranged in a row or according to another geometric pattern.

The preferred embodiment in fig. 3 shows the row of operational units 1 during operation. The corrugated lines 18, show a schematic representation of the thermal field of the geological formation. The letter "D" denotes those wells from which heat energy is drawn, and the letter "R" denotes the wells that are subject to regeneration. The system according to the invention in the embodiment shown in Fig. 3 comprises only one control unit 9 and turbogenerator 12 circuit, although it may comprise many control units and turbogenerator circuits. The method according to the invention is also implemented in this system.

The schematic diagram of the ground part of the system according to the invention is shown in the embodiment in fig. 4. Operational units I, II, III and IV are connected via central conduit, connected to the power grid 13, comprising conduits 5 in which a heat-receiving medium 7 flows. The upper parts of the operational units are arranged in a row, which saves time when building wells 2, 3. The figure shows schematically the transportation routes 19, useful during the construction of the installation. The method according to the invention is also implemented in this system.

Fig. 5 shows a graph of temperature dependence on the operation time of an operating unit containing two wells for acquiring thermal energy in the embodiment of the system and the method according to the invention compared to the operation of the state-of the art system. The upper part of the graph shows the temperature amplitude for wells 2 and 3 and the enthalpy for the ACEEESS system, and the lower part of the graph shows the simulation for a system with continuous depletion of thermal resources on a different time scale. As can be seen in the system according to the invention, the temperature amplitude is about 5 °C.

The invention makes it possible to obtain dissipated heat energy from a inexhaustible, permanent source of heat.

It also allows to obtain heat with a continuous heat supply to the receiving device without fluctuations and without heat flow disturbances. The above is crucial for generating a stable linear energy flow with pre-designed performance, regardless of the heat transfer coefficient from the accumulated heat resource.

The invention implements the practical application of the theory of potential energy field, which causes the phenomenon of depletion / heat charging.

The above results in an inexhaustible and subordinated use of geo-plutonic energy, constantly available to consumers throughout the year.

The method and system according to the invention enables a significant reduction in the required depth and size of a well in hot / warm geological formations that become operative with a lower heat transfer temperature from the geological formation to the heated transfer stream. Such a reduction can be up to about 50% compared to other heat collection systems.

ACEEESS has unique flexibility in designing and performing various configurations of the distribution of the production unit .

It will be clear to the person skilled in the art how the installation can be constructed to carry out the method and system according to the invention. The following are described the exemplary recommendations for use during construction.

The construction of the conduits in the form of pipes surrounded by a controlled vacuum chamber in which the vacuum can be obtained again, while the outflow channels are drained and reach the bottom of the borehole, leads to the elimination of unbalanced thermal expansion of individual pipes, causing welded joints to break. Such a system is covered by other patents. For the purposes of the present invention, thermal failures of both inlet and outflow lines are maintained in a safe condition.

It is advantageous to seal the inlet lines with the geological formation when drilling side walls.

This is achieved by means of a sealing system with a concrete sealant that fills the borehole if the collection column is thoroughly embedded in the concrete, while the sealant is pushed out and replaced with air, gas or liquid and pushes them through the sealing concrete mix. A concrete setting retarder is used, with a controlled time of inlet conduits dipping in the mix. The drilling operation in the hot/warm geological formation is related to cooling by a drill working with a cryogenic mixture and an installation for controlling the temperature reduction in the well; all this would prevent a steam explosion and an earthquake during drilling. This action has a significant impact on lowering the pipeline housing while controlling the heat recovery process and supports immediate compensation for thermal expansion of the steel structure. The drilling technology is significant for using the mixing of the drilling and flushing slurry with cement and moderator. The mixture is introduced under high pressure during drilling into pores, cracks and other empty spaces to solidify into stone and seal the formation. The purpose of this operation is to improve the heat transfer capacity and continuous isolation of collection operations from the invasion of unwanted water, gas, oil, radioactive substances from geological formations. Reference signs:

1. operational unit

2. well

3. well

4. heat-receiving system

5. conduit

6. flow-inducing means

6a . pump

7. heat-receiving medium

8. temperature sensor

9. control unit

10. system converting thermal energy into electric current

11. condenser

12. turbogenerator

13. power grid

14. circuit of the turbogenerator driving medium

15. circuit of the heat-receiving medium

16. distance between wells

17. heat exchanger

18. thermal field lines of geological formation

19. road

"D" - a well from which heat energy is taken

"R" - a well subject to regeneration.