SU1390345A1 - Method of recovering geothermal energy - Google Patents

Abstract

The invention relates to a pit case and mb. Is used in extracting the heat of rocks with the subsequent use of geothermal heat carrier for heat supply in areas with a shortage of fuel and electricity. The goal is to increase the extraction of geothermal energy. The method includes bzfenie injection and pumping wells (C). On the inclined interval of injection C, a basic system of vertical fractures is formed by hydraulic fracturing. Then C is sorted to the depth-, where the temperature (t) of the subsoil exceeds the maximum T in the heat supply network, and an additional system of vertical fracturing of the fracturing is formed. Part of the coolant extracted from the additional fracture fracture system is mixed with the coolant coming from the main fracture system. The depth of formation of the primary and secondary fracture fracture system is determined from the ratios H, tMMH 1 i 357t t + min) 1, where t. t. Ndrp and mlks С „cn 0,357tt ,, 3: tS (1,357t -0.557t ,, -t, / t min Лркс from respectively minimum, maximum T heat carrier in the heat supply network and T processed heat carrier, О С; (7 - geothermal gradient. 2 Cp f-ly. 1 ill. and WITH Feo about 00 k4 SL

Description

The invention relates to mining and can be used in the extraction of heat of rocks with the subsequent use of geothermal coolant for heat supply areas with a shortage of fuel and electricity.

j The aim of the invention is to increase the recovery of geothermal energy. Q body vertical cracks 5. Below

live 2 at the first inclined interval to the surface are heat insulated ... This is necessary to eliminate the heat exchange of coolant flows moving through the annular space and tubing string 3, and to maintain the temperature potential of the heat transfer fluid from the supplement. The drawing shows one of the possible geothermal extraction schemes energy.

The scheme contains injection 1 I and production 2 wells; insulated tubing string 3; main vertical cracks 4 fractures; additional vertical fractures 5 fracturing; mixer 6 heat carrier flows from the main and additional vertical cracks; turbine 7 for power generation ;; heating system 8; the first 9, the second 10 systems of horizontal cracks; wells 11 and 12, operating the first horizontal fracture system; wells 13 and 14, operating the second horizontal pumping equipment system 15 for injection and water into the main And additional vertical fractures; pumps 16 to 19; containers 20 and 21 filled with water; valves 22 - 30; power lines 31; packer 32; pipelines 33 - 42; adjustment adjustment 43.

The proposed method is carried out as follows.

At the first stage, the main and additional vertical cracks 4 and 5 are formed. For this purpose, the injection well 1 is drilled to the depth H, and then with the help of a hydraulic rock break in an inclined interval of the well.

1, vertical cracks are created 4. The injection well 1 is drilled to a depth H, determined by the relation (10), and in the second inclined interval form an additional; body vertical cracks 5. Drilling a production well

2to connect its inclined intervals first with main vertical fractures and then with additional 5. Install .in the production well- 2 tubing string 3, which in the section from the conjugation of the main trunk of the mining squash control of the main wellbore 2 with the first inclined interval To eliminate hydraulic communication with additional vertical cracks, 15 we install a packer 32. Drilling of wells 11–14 is carried out, after which systems 9 and 10 are formed horizontal, and also reservoirs 20 and 21 are created. torye filled.

20 with water.

Water with a temperature equal to the temperature of the spent heat carrier from the heat supply system 8 through the pipe 33 and from the turbine 7 through the pipe 25 by the pump 38 is pumped through well 1 into the main 4 and additional 5 vertical frac hydraulic pipes. The distribution of the amount of water

The 30 main 4 and additional 5 vertical cracks are chosen in such a way that the ratio (11) is satisfied and implemented with the help of the adjusting valve 43 by changing the hydraulic resistance of the annular space of the mining well 2. Move along the cracks 4 and 5, water as a result of heat exchange with rocks heats up according to

35

40

proper to temperatures

t v., H and

45

50

55

The coolant with a temperature t, is given to the surface through the annular space (between the heat-insulated part of the pump-compressor column 3 and the casing) of well 2 and enters the mixer 6 The heat carrier with temperature t flows to the surface through the tubing column Zo Part of it the turbine 7 is directed, and the other part is fed to the mixer 6. The ratio between the amounts of heat carrier from additional vertical cracks 5, directed for heat supply and electricity generation, is addicted (12). The use of coolant from additional vertical cracks for power generation justifies

body vertical cracks 5. Below

live 2 at the first inclined interval to the surface are heat insulated ... This is necessary in order to exclude heat exchange of coolant flows moving through the annular space and tubing string 3 and to maintain the temperature potential of the heat transfer medium from the addition of the main well bore 2 at the first inclined interval in order to eliminate hydraulic communication with additional vertical cracks, 5 we install a packer 32. Drilling of wells 11-14 takes place, after which systems 9 and 10 form a horizon lnyh and create containers 20 and 21 which are filled.

0 water.

Water with a temperature equal to the temperature of the spent coolant from heat supply system 8 through pipeline 33 and turbine 7 through pipe 5 to wire 38 by pumping units 15 is injected through well 1 into main 4 and additional 5 vertical fracturing criteria. At the same time, the distribution of the amount of water directed to the main 4 and additional 5 vertical cracks is chosen in such a way as to satisfy ratio (11) and is performed by means of an adjustment valve 43 by changing the hydraulic resistance of the annular space of the production well 2. cracks 4 and 5, the water is heated by heat exchange with rocks, respectively 5

0

proper to temperatures

t v., H and

five

0

five

The coolant with a temperature t, is supplied to the surface through the annular space (between the heat-insulated part of the tubing string 3 and the casing) of well 2 and enters the mixer 6. The coolant with the temperature t flows to the surface through the tubing string Zo Part of it the turbine 7, and the other part is fed to the mixer 6. The ratio between the quantities of coolant from the additional vertical cracks 5, directed for heat supply and electricity generation, is determined by becomes dependency (12). The use of heat carrier from additional vertical cracks for power generation is based on its higher temperature potential than that of the main vertical cracks coolant, and, consequently, on its high efficiency in power generation. After the mixer 6, the coolant with the temperature enters the heat supply system 8, from where the spent coolant is directed to the injection well 1. Electricity, which is charged by the turbine 7, passes through the power lines 31 to the pumps 15-19, In the above described operation mode, the pumps 16-19 are turned off , and valves 22-30 are closed,

In the event of a decrease in heat-energy-consuming part of the coolant from the main 4 and additional 5 vertical cracks in wells 14 and 11, it is pumped into systems 9 and 10 of horizontal tragcin, where with the help of the included pumps 19 and 16

Into the tank 20, the Other part of the coolant through the pipeline 35 is supplied to the coolant extracted from the pipes 4 and mixed with it, consistently enters the mixer 6 and the heat supply system 8, and from there through the pipeline 42 into the container 21, from which it is pumped into the container 20 The coolant from the system 10 horizontal cracks in the well and the pipeline 40 also enters the mixer 6 and the heating system 8, from which the spent coolant is again pumped through the pipeline 42 into the container 21, the depth of formation of horizontal tons In 100–200 m, the reason is the absence of heat exchange with the surface.

Claims (3)

Invention Formula 1, Method for extracting geothermal energy, including drilling at less its circulation. Moving as required by a pair of pumped out and pumped by the 10 and 9, the coolant is cooled, heating the rock, respectively to temperatures .t and t. ,, chilled P coolant through wells 13 and 12 and pipelines 39 and 38 from systems 10 and 9 of horizontal cracks are supplied to injection well 1, In this mode, valves 22, 26 - 28 are open, 23-25, 29 and 30 are closed, and pumps 17 and 18 are turned off . With increasing heat and energy consumption, valves 23-30 are opened, pumps 17 and 18 are turned on and, on the contrary, backlocks 22 and 28 are closed and pumps 16 and 19 are turned off. Water from tanks 20 and 21 is fed through pipes 36 and 41 and wells 12 and 13 in systems 9 and 10 horizontal cracks. Moving on them, it heats up to temperatures t and t, respectively. Cooling by HP h1g1 childbirth. Part of the heated coolant from the system 9 and 10 horizontal cracks in the well 11 is fed to the turbine 7, from where the spent coolant through pipelines 38 and 37 again  - M “K; bT 0.357t 5 (1.3571 „-0.357t  from  main (the depth of the formation of the main and vertical oblique wells, the formation of vertical fracturing fractures at the inclined intervals of the main system, the flow of water into the subsoil Q through the injection well; supplying the coolant to the heat supply network, in which, in order to increase the extraction of geothermal energy, the wells are re-drilled to a depth where the temperature is week p exceeds the maximum temperature in the heat supply network; they form an additional system of vertical triggers of hydraulic fracturing, with a part of the coolant being extracted from the additional system of fractures of hydraulic fracturing 0 five 0 va. Mixed with the coolant coming from the main fracture system, and the depth of the formation of the primary and secondary fracture cracks is determined from the ratio n 1- main / 6 t  from full body cracking system, n min - accordingly, the minimum, the maximum temperature of the heat carrier. The body in the heating network and the temperature of the treated coolant, 13903456 S - geothermal gradient,. 2, the method according to claim 1, about tl and h and y - y and i with the fact that water into the main and additional systems of vertical fracture fracturing serves on one injection well with a ratio W OS.N (A, -t T Acn-te.) ( Lop .ot the amount of water injected and the main I. and additional systems of cracks, I t - t is the temperature of the heat-carrier in the heat supply network, p. The rise of the coolant to the surface from the main and additional fracture fracture systems is carried out, respectively, through the annular space and the tubing string of the pumping well. ) To72 (( T 3. The method according to claim 1, characterized in that, in order to accumulate geothermal energy in periods with low heat energy consumption and utilization of heat accumulated by rocks while increasing heat energy consumption, two systems form horizontal cracks, PS1 which organize the circulation of heat-transfer fluid from main and additional vertical cracks, and then the circulation of water filling the vessels formed on the surface, 33 S ff