JP4973936B2 - Carbon dioxide underground storage method and underground storage system - Google Patents

Description

  The present invention relates to underground storage of carbon dioxide in exhaust gas generated from a plant facility such as a power plant. More specifically, the carbon dioxide ground having improved carbon dioxide penetration and diffusibility. The present invention relates to an intermediate storage method and an underground storage system thereof.

  As a measure against global warming, Japan is obliged to reduce the average greenhouse gas emissions from 2008 to 2012 by 6% compared to 1990 levels. Achieving this goal is an urgent need, and the Kyoto Protocol Target Achievement Plan has been formulated, which significantly strengthens the current global warming countermeasures, and the reduction of greenhouse gases (mainly carbon dioxide) by sector has been reduced. It is listed. In 2010, the energy conversion sector such as power plants decreased 16.1% and the industrial sector decreased 8.6%, while the transportation sector increased 15.1% and the business and other sectors increased 15%. The household sector is expected to increase 6% or less. However, in Japan, energy saving is progressing in the industrial sector where a carbon dioxide reduction effect can be expected. Therefore, storage of discharged carbon dioxide in the ground or in the sea is being considered as a new reduction policy in the industry. .

  Greenhouse gases include carbon dioxide, methane, and CFC substitutes. More than 90% of greenhouse gases emitted in Japan are carbon dioxide. The United States and the EU are working on geological storage of carbon dioxide as an effective method for reducing greenhouse gases. A large amount of carbon dioxide is contained under the seal layer and the cap lock layer. However, when carbon dioxide is injected into the basement continuously in large quantities with a gas or supercritical fluid, it tends to be in a solid state (plum), and there is a problem in permeability and diffusivity. In addition, since carbon dioxide, which is a gas or a supercritical fluid, is lighter than water, if there is a gap in the seal layer or cap-lock layer, there is a risk of leaking to the ground side. There may be no geological formation near the plant facility that is suitable for storage so as to be surely provided with a seal layer or cap lock layer without a gap. There is a treatment method that can efficiently treat carbon dioxide, has good permeability and diffusion in the ground, and is securely fixed in the ground even in general geological environments that do not have a perfect seal layer or cap lock layer. It is desired.

Patent Document 1 “Operation Method of Carbon Dioxide Separation and Recovery System Using Steel Works Equipment” shows a system for separating and collecting carbon dioxide from by-product gas of steel works. The carbon dioxide recovered at the steelworks is supplied to the fixed equipment by means of transportation such as pipes, and fixed by injecting the fixed equipment into the underground aquifer, injecting into the depleted gas field, or storing in the ocean. It has been proposed to The “gas liquefaction settling device” in Patent Document 2 describes that carbon dioxide and seawater liquefied by applying high pressure are alternately pumped into the deep sea.
JP 2004-237167 A JP 2000-227085 A

  The object of the present invention is to prevent clogging caused by bubbles and improve the permeability and diffusibility in the ground. Carbon dioxide can be dispersed and fixed safely in the gaps between soil particles or rocks in the ground. An object of the present invention is to provide an underground storage method and an underground storage system for carbon dioxide that can be efficiently mixed or dissolved in water.

In order to achieve the above object, the method for underground storage of carbon dioxide according to claim 1 according to the present invention includes the step of pumping the groundwater of a deep aquifer from the pumping well to make the injected water, To the injection well provided so as to reach the deep aquifer and press-fitting a pulsation pressure having a frequency of 0.5 to 30 Hz generated by the reciprocating motion of the piston of the pulsation generator; Forming a gas-liquid mixed fluid by making carbon dioxide into fine bubbles having a diameter of 10 to 50 μm and mixing or dissolving the injected injected water into a fine bubble.

  A second aspect of the present invention is the invention according to the first aspect, further comprising the step of applying vibration energy to the gas-liquid mixed fluid by a vibration generator installed at a bottom of the injection well.

The underground storage system for carbon dioxide according to claim 3 according to the present invention includes a pumping device for pumping deep groundwater from a pumping well, and an injection water injection device for feeding the pumped groundwater into the injection well as injection water. And a low-frequency pulsation generator having a frequency of 0.5 to 30 Hz for applying pulsation pressure to the injected water, carbon dioxide from a storage tank to the injection well. At the upper part of the injection well provided so as to reach the deep aquifer and the gas injection device to be fed, the carbon dioxide is made into fine bubbles with a diameter of 10 to 50 μm and mixed or dissolved in the injection water for gas-liquid mixing And a microbubble device for generating a fluid.

  A fourth aspect of the present invention is the invention according to the third aspect, wherein the microbubble device has an injection pipe for injecting the carbon dioxide obliquely downward, and is constituted by a rotating cylinder. .

  A fifth aspect of the present invention is the invention according to the third aspect, further comprising a vibration generating device that applies vibration energy to the gas-liquid mixed fluid at a bottom portion of the injection well.

  According to the carbon dioxide underground storage processing method of claim 1, since carbon dioxide is microbubbled into the groundwater pumped up from the deep aquifer and mixed or dissolved, a gas-liquid mixed fluid containing a large amount of bubbles is generated. It can diffuse very quickly over a wide range of deep aquifers. Since carbon dioxide bubbles easily enter the gaps between soil particles or rocks, they are trapped and fixed stably there. There is no need for a shielding layer such as a cap layer above the reservoir. Since the low-frequency pulsation pressure is applied to the injected water, the fluidity of the gas-liquid mixed fluid is improved, and the gas-liquid mixed fluid can be injected faster than the case where the gas-liquid mixed fluid is sent to the deep aquifer only by the static pressure. The pulsating pressure prevents clogging due to fine bubbles. Since micro-bubble generation is performed at the top of the injection well, for example, compared to the case of micro-bubble generation at the bottom of the injection well where the water pressure is high, the generation of bubbles is easy and the void ratio containing a large amount of carbon dioxide bubbles (constant) A gas-liquid mixed fluid having a high volume ratio of fine bubbles occupying the volume of the gas can be produced.

  According to the second aspect of the present invention, the stage in which the vibration energy is applied to the gas-liquid mixed fluid by the vibration exciter installed at the bottom of the injection well is clogged by bubbles in combination with the low-frequency pulsation pressure in the injection water. Is prevented, and the gas-liquid mixed fluid can be diffused over a wide area of the deep aquifer.

  According to the carbon dioxide underground storage system of claim 3, carbon dioxide is microbubbled and mixed or dissolved in the groundwater pumped from the deep aquifer, so that a large amount of carbon dioxide can be treated. Such a gas-liquid mixed fluid containing a lot of bubbles has good permeability to soil particles or rock crevice, and reacts with soil particles or rock minerals to change into carbonate minerals, for example, so carbon dioxide into the ground. Can be fixed. Since the low-frequency pulsation generator is provided between the injection water injection device and the injection well, the fluidity of the gas-liquid mixed fluid is improved and the gas-liquid mixed fluid can be efficiently injected into the deep aquifer. Compared with the case of generating bubbles against the water pressure at the bottom of the injection well, the microbubble device provided in the upper part of the injection well is easy to generate bubbles. As the fine bubbles progress from the top of the injection well to the bottom, the shape becomes smaller due to the gradually increasing water pressure, and they tend to enter the gap between the soil particles or rock.

  According to the fourth aspect, since the microbubble device is composed of a rotating cylinder, it can give a swirling flow to the injected water. That is, bubbles can be generated without depending on the flow of the gas-liquid mixed fluid to the deep aquifer. Since the injection pipe for injecting carbon dioxide obliquely downward is provided at a place where the flow rate of the injected water between the cylinder and the casing pipe is high, the pressure difference between the injected water and the carbon dioxide is increased. It is promoted, and a lot of fine bubbles are generated, and a gas-liquid mixed fluid having a large void ratio can be generated.

  According to claim 5, since the vibration generator is installed at the bottom of the injection well, the clogging of bubbles is prevented by the vibration energy applied to the gas-liquid mixed fluid, and the gas-liquid mixing is performed in a wide area of the deep aquifer. The fluid can be diffused.

  The carbon dioxide underground storage method and its underground storage system according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a configuration diagram of a carbon dioxide underground storage system according to the present invention. The carbon dioxide storage system 100 includes a pumping device 1 that pumps ground water 53 from a pumping well 20 that reaches the deep aquifer 50, and an injection well 21 that reaches the deep aquifer 50. Separated from the injection water injection device 2 to be fed, the low frequency pulsation generator 3 that is provided between the injection water injection device 2 and the injection well 21 and applies pulsation pressure to the injection water 54, and the exhaust gas of the external plant facility 30 A gas press-fitting device 4 for sending the recovered carbon dioxide 55 to the injection well 21 and an upper portion in the injection well 21, the carbon dioxide 55 is made into fine bubbles and mixed with the injection water 54 to generate a gas-liquid mixed fluid 56. And a microbubble device 5. Specifically, the plant facility 30 includes a thermal power plant, a waste incineration facility, an oil refining facility, a cement facility, and the like.

  The deep aquifer 50 is a layer composed of a fine sand layer or the like and saturated with salt water that is not suitable for water resources, and it is considered that carbon dioxide is injected and used at a depth of 500 to 1200 m. The carbon dioxide 55 is made into fine bubbles in the upper part of the injection well 21, and part of it is dissolved in the injection water 54, and part of the carbon dioxide 55 is dissolved but becomes a gas-liquid mixed fluid 56 in the form of bubbles and is pressed into the deep aquifer 50. . Although there are many layers from the ground surface 58 to the deep aquifer 50, illustration is omitted.

The carbon dioxide 55 can be diffused widely in the deep aquifer if it is microbubbled and mixed or dissolved in the injected water 54. Since the fine bubbles 34 have a remarkably large contact area with the groundwater 53, the dissolution rate of carbon dioxide is several hundred to several thousand times faster than the case where the carbon dioxide is present in the ground as a mass of gas or supercritical fluid. In addition, since the fine bubbles 34 enter the gaps between the soil particles or the rocks, the carbon dioxide is fixed. Therefore, it is effective even in a general deep aquifer where no reliable seal layer or impermeable layer exists above. Since the weight of carbon dioxide at 1 atm and 25 ° C. is 1.8 kg / m ³ , for example, 50 kg of carbon dioxide dissolved in 1 m ³ of water is approximately 28 m ³ of gas at 1 atm 25 ° C. There is to be immobilized in groundwater 1 m ^3.

Here, the fixation of carbon dioxide occurs in the following process. Carbon dioxide that is finely foamed and dispersed and injected into the minute gaps of soil particles or rocks is trapped as residual gas in the rocks when adsorbed on the surface of rock minerals or by the capillary effect, but in the surrounding groundwater It gradually dissolves. Dissolved carbon dioxide reacts with various ions and the surrounding mineral abundant in groundwater, for _{example, 2CO 2 + 3H 2 O +} CaSiO 3 → Ca 2+ + 2HCO 3 - + H 4 SiO 4 (1) ionizes as formula Stabilize more in groundwater. Furthermore, a reaction of Ca ²⁺ + 2HCO ₃ ⁻ → CaCO ₃ + CO ₂ + H ₂ O (2) occurs, and half of CO ₂ returns to the formula (1), but since CaCO ₃ is a carbonate compound, carbon dioxide is Almost permanently fixed.

  The pumping device 1 includes a pumping well 20 of a double pipe 8 composed of an inner pipe 6 and an outer pipe 7, a pumping pump 9, a jet suction unit 10, a water collection tank 11, and the like. In order to pump up the ground water 53, the pressurized water 57 is sent to the inner pipe 6 by the pumping pump 9, the ground water 53 is pumped up by the jet suction unit 10, and stored as the injected water 54 in the water collecting tank 11. The jet suction unit 10 creates a negative pressure by increasing the flow rate of the pressurized water 57 and sucks the groundwater 53. The water supplied to the pumping pump 9 may be reused by circulating the groundwater stored in the water collection tank 11.

  The injected water press-fitting device 2 includes a press-in pump 12 for pressure-feeding the injected water 54 to the injection well 21, a pressure flow control valve 13, and the like. The pressure flow control valve 13 opens the valve to return the injected water 54 to the water collection tank 11 when the resistance of the injected water 54 of the injection pump 12 exceeds a certain value. Since the distance between the pumping well 20 and the injection well 21 is usually 500 m to 1 km apart, a water injection tank connected by a pipeline may be provided separately from the water collection tank 11 and incorporated into the injection water injection device 2.

  The groundwater pumped up from the deep aquifer is called brine and is preferred as injected water. Brine has a function of suppressing the disappearance of fine bubbles because it contains a large amount of electrolyte ions. Brine has a salinity of more than one-third that of seawater and cannot be used in daily life, so it is easy to obtain local understanding. Aquifers with brine are widely distributed in the Cretaceous Tertiary to Quaternary sedimentary basins. In the brine, electrolyte ions lower the gas solubility in proportion to their concentration (Salting out phenomenon), so that the fine bubbles 34 can be generated at a high density by preventing the fine bubbles 34 from escaping.

  The low frequency pulsation generator 3 includes a controller 14 and a pulsation generator 15. The controller 14 can specify the period and magnitude of the pulsation pressure. The pulsation pressure is a low frequency, specifically 0.5 Hz to 30 Hz. Since the pulsation pressure is low frequency, it is transmitted to the bottom of the injection well 21. Since the pulsation pressure increases the fluidity of the gas-liquid mixed fluid 56, the pulsation pressure is more efficient than press-fitting only with a static pressure.

  As an example, the plant facility 30 includes a separation and recovery device 17 for carbon dioxide contained in the exhaust gas of the combustion furnace 16. According to the chemical absorption method, the concentration of carbon dioxide can be concentrated to 99% or more. However, in this fine bubble injection method, carbon dioxide can be used for injection even if it is lower. You may provide the tank which stores the collect | recovered carbon dioxide temporarily. A large thermal power plant emits 2 to 3 million tons of carbon dioxide annually.

  The gas injection device 4 includes a storage tank 24 and a compressor 22. Although not shown, a pressure regulating valve, a flow meter, and a pressure gauge are attached. The carbon dioxide 55 is sent to the storage tank 24 by the transportation means of the pipeline or the tank lorry 18, and is selected in consideration of the transportation distance between the plant facility 30 and the injection well 21 and the economic efficiency due to the annual underground storage amount. When carbon dioxide is transported by the tank truck 18, the carbon dioxide 55 is transported in a liquefied state under high pressure. In this case, since the carbon dioxide 55 is returned from the liquid to the gas, the volume increases several hundred times.

  The microbubble generator 5 is provided in the upper part of the injection well 21, converts the carbon dioxide 55 into microbubbles, mixes it with the injection water 54, and generates a gas-liquid mixed fluid 56. The microbubble device 5 is connected to the insertion tube 26 and is rotated by a rotary drive device 31 that rotates at high speed on the ground side. Injection water 54 is pressed between the casing tube 25 and the insertion tube 26, and carbon dioxide 55 is pressed into the insertion tube 26. Microbubbles 34 are generated by the microbubble generator 5 and become a gas-liquid mixed fluid 56, which is fed into the deep aquifer 50 from the slit 35 on the bottom side surface of the casing tube 6.

  While the fine bubbles 34 move toward the bottom of the injection well 21, the bubble volume gradually decreases as the water pressure increases, and the fine bubbles 34 become finer than when bubbles are generated. More specifically, the fine bubbles 34 change phase into bubbles, droplets, or supercritical fluid bubbles depending on the pressure and temperature conditions and the gas purity of the carbon dioxide 55 while moving to the bottom of the injection well 21. . The present invention includes such a fine bubble phase change. The position of the injection well 21 and the injection depth can be determined in consideration of the phase change of the bubbles based on the site conditions (geological structure, geothermal pressure, geothermal temperature) of the deep aquifer 50.

  FIG. 2 is a sectional view of a double pipe of a pumping well. The jet suction unit 10 has a reverse funnel type in order to increase the flow rate of the pressurized water 57 from the inner tube 6. Since the inside of the reverse funnel has a negative pressure, the groundwater 53 is sucked in. The sucked groundwater 53 rises between the inner pipe 6 and the outer pipe 7.

  FIG. 3 is a cross-sectional view of a detailed microbubble device. The microbubble device 5 includes a cylindrical body 40 that has an injection tube 41 that injects obliquely downward on its side surface and is connected to an insertion tube 26 that is rotated by a rotation drive device 31. Since the injection water 54 passes through the narrow flow path between the cylinder 40 and the casing tube 25, the flow velocity is increased. The higher the flow rate, the lower the pressure, and the carbon dioxide 55 is easily extracted as the fine bubbles 34. The generated gas-liquid mixed fluid 56 is dragged and rotated by high-speed rotation (for example, 500 to 3000 rpm) of the cylindrical body 40, and is subdivided by the injection pipe 41. Therefore, the diameter of the fine bubbles 34 is as small as 10 μm to 50 μm and stays for a long time without disappearing in water.

The void ratio of the gas-liquid mixed fluid 56 can be about 30 to 50%. For example, in order to store 100,000 tons of carbon dioxide annually as fine bubbles in the deep aquifer, about 300 tons / day of carbon dioxide is mixed into the groundwater pumped up. The amount of groundwater pumped per day depends on the geological structure of the target sedimentary basin, but in actual results, groundwater from the deep aquifer of the geological structure with a porosity of 30 to 40% is averaged to 1100 m ³ / I can pump out the sun. Carbon dioxide in the microbubbles is high in pressure because of high pressure, and considering dissolution, if conditions such as pressure and temperature are good, 300 tons of carbon dioxide is mixed in 1100 m ³ of water in the form of microbubbles. Can be injected.

If about 300 tons / day of carbon dioxide is made into fine bubbles and mixed into 1100 m ³ / day of groundwater pumped from a pumping well, for example, 100,000 tons of carbon dioxide will be grounded in a deep aquifer at a depth of about 1000 m per year. Can be stored inside. The world's deep aquifers are estimated to be able to store at least 2 trillion to 3 trillion tons of carbon dioxide underground, so they have sufficient storage potential as a measure against global warming.

  When the gas-liquid mixed fluid 56 having a high void ratio is fed into the gap between the formations, it tends to cause a trouble of blockage due to the fine bubbles 34. As a countermeasure for this, pulsation injection is effective in which the gaps in the formation are pulsated and the fine bubbles 34 are injected while being regularly reduced or moved. An indispensable condition for smooth injection processing by pulsation injection is to generate a large amount of fine bubbles 34 having a bubble diameter of 50 μm (0.05 mm) or less. Trouble cannot be avoided.

FIG. 4 is a configuration diagram of the low-frequency pulsation generator 3. The controller 14 includes a motor 27 and a hydraulic cylinder 28 as an example. When the motor 27 rotates, the piston of the hydraulic cylinder 28 moves, and a constant period of hydraulic pressure as shown in the graph G1 is applied. With this hydraulic pressure, the diameter of the rubber tube 29 of the pulsation generator 15 is expanded and contracted. The hydraulic pressure can be controlled by providing a solenoid valve at the outlet of the hydraulic cylinder 28 to release the pressure. If the rotation of the motor 27 is 1200 rpm, the cycle is 20 times per second (20 Hz). As shown in the graph G2, the pulsating pressure is applied to the pressure of the injected water 54 that has exited the press-fitting pump 12, and the injected water 54 has a pressure as shown in the graph G3. A check valve may be provided on the upstream side of the low-frequency pulsation generator 3 so that pressure is not transmitted in a high load state. The amplitude of the pulsation pressure is, for example, when the water pressure of the injected water 54 is Pα, and the water pressure Pαd after pulsation has an amplitude coefficient of 0.5, and (Pα−0.5Pα) <Pαd <(Pα + 0.5Pα) It can be. Pα is preferably about 1 to 3 MPa (= about 10 to 30 kg / cm ² or more).

Usually, the frequency of the pulsation pressure is 0.5 to 30 Hz. Here, if considering that it is a gas-liquid mixed fluid, 0.5 to 10 Hz is desirable. For example, the natural frequency f ₀ of a bubble with a bubble diameter of 1 mm is about 3 kHz, and the finer the bubble diameter, the higher the natural frequency with a frequency higher than 3 kHz. In a high-frequency region higher than the natural frequency f _{0 of the} bubble, a wave cutoff phenomenon occurs in which the pressure wave of the pulsation pressure cannot pass through the bubble group and does not propagate beyond the bubble group. On the other hand, when the frequency exceeds 10 Hz, the energy of the pressure wave that permeates the bubble group rapidly decreases. Therefore, the frequency of the pulsation pressure in this system is set to 10 Hz or less where the transmission power of the pulsation wave is strong. The phenomenon in which the propagation speed of the pressure wave becomes slow after the pressure wave reaches the bubble is due to the fact that the propagation energy of the pressure wave is converted into the energy for reducing the bubble.

  FIG. 5 is a pressure relationship diagram of injected water in the injection well and carbon dioxide, which is a gas. The depth L1 of the microbubble device 5 should be a depth that does not cause structural problems even if it is integrally rotated with the insertion tube 26, and is preferably 5 to 50 m. Let P1 be the water pressure of the injected water 54 at the depth L1. The depth to the slit 35 at the bottom of the injection well 21 is L0. Furthermore, the water pressure at the depth L0 is P0. In the case of the gas-liquid mixed fluid 56, there is a decrease in water pressure (Pβ) due to the fine bubbles 34, so the injected water 54 is pressurized by that amount (Pβ). That is, the injection pressure of the injection water 54 needs to be Pαd + Pβ. From this pressure, the discharge pressure of the press-fit pump 12 is determined. As for Pβ, an injection test in a static pressurization state is performed on site, a water pressure is measured near the bottom slit 35 of the injection well 21, and a calibration of a decrease in water pressure accompanying a change in the generation amount of the fine bubbles 34 is performed. To grasp. Even in the case of static pressurization, the Pβ of the calibration value obtained in the injection test includes not only the influence of the buoyancy of the microbubbles 34 but also a static pressure energy decrease absorbed by the microbubbles 34. ing. Since the pressure of the injected water 54 at L1 becomes P1 + Pαd + Pβ, the gaseous carbon dioxide 55 is set to P1 + Pαd + Pβ + C so as to have a larger value. C was about 1 to 3 MPa (= about 10 to 30 kg / cm 2).

  FIG. 6 is a configuration diagram when a vibration generator is installed at the bottom of the injection well 21. The vibration generating device 49 includes a vibration exciter 51, a coil 60, a reaction force plate 62, and a magnet 59 stored in a storage box 52. The vibration exciter 49 is installed on the concrete 48 having a height of about 1 m, which is solidified at the bottom of the casing tube 25 of the injection well 21, with three suspension wires 47. Power is sent by a power cord 46 fixed to the hanging wire 47. Magnet 59 is magnetized and coupled to anchored embedded iron plate 61 provided when concrete 48 is placed. By erasing the magnetic force of the magnet 59 by remote control, the vibration generator 49 can be recovered on the ground. In the casing tube 25, a water pressure gauge 42, a thermometer 43, and an electric conductivity meter 44 are arranged according to the depth. The example of arrangement | positioning of these measuring instruments in an AA cross section and a BB cross section is shown on the right side of FIG.

  Since the microbubbles 34 do not completely change into droplets, pulsating injection is essential. When it is difficult to obtain the effect of the pulsation injection only by the low frequency pulsation generator 3 on the ground side, the vibration generator 49 is installed at the bottom of the injection well 21 near the slit 35. Kinetic energy is applied to the gas-liquid mixed fluid 56 from the vibration exciter 49, and the gas-liquid mixed fluid 56 is used in combination as auxiliary equipment for preventing the clogging of the fine bubbles 34 during injection. While checking the behavior of the pulsating water pressure based on the water pressure gauge data provided in the vicinity of the slit 35, the vibration generating force of the vibration generator 51 is adjusted. The exciter 51 may be a variable frequency electromagnetic vibrator used for elastic wave exploration of a relatively shallow geological structure, and is built in a high-pressure waterproof storage box 52. The storage box 52 is supported by a plurality of corrosion-resistant coils 60, and the lower end side of the coil 60 is fixed to a reaction force plate 62 made of a material having high electromagnetic wave shielding performance. The magnet 59 for generating a magnetic force has an integrated structure.

  The amount of carbon dioxide fine bubbles 34 dissolved in the injection water in the injection well 21 is determined by calibrating the relationship between the newly dissolved carbon dioxide weight and the electrical conductivity of the groundwater before being injected into the injection well 21 in advance. The amount of dissolved carbon dioxide is estimated using the calibration result for the electrical conductivity measured by the electrical conductivity meter 44.

  FIG. 7 is a flowchart of a carbon dioxide underground storage method. Reference numerals S70 to S74 denote the respective stages. S70 is a stage in which groundwater is pumped from the deep aquifer. S71 is a stage where the injected water is injected into the deep aquifer by applying pulsating pressure to the injection well. S72 is a step of creating a gas-liquid mixed fluid by making carbon dioxide into fine bubbles and mixing the injected injected water at the upper part of the injection well. S73 is a step in which it is determined whether a blockage due to bubbles occurs. S74 is a stage in which when a blockage occurs in S73, a vibration generator is installed at the bottom of the injection well to give vibration energy to the gas-liquid mixed fluid, thereby activating the movement of fine bubbles.

  The present invention is suitable for underground storage of other global warming gas of carbon dioxide. It can also be applied to EOR (crude oil enhanced recovery method) in which carbon dioxide is injected and crude oil is extracted.

It is a block diagram of the underground storage system of a carbon dioxide. Example 1 It is sectional drawing of the double pipe of a pumping well. Example 1 It is sectional drawing of a microbubble generation apparatus. Example 1 (Example 1) which is a block diagram of the low frequency pulsation generator. It is a pressure related figure of the injection water and carbon dioxide in an injection well. Example 1 It is a block diagram at the time of installing a vibration generator in an injection well. Example 1 It is a flowchart of the underground storage method of a carbon dioxide. Example 1

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pumping apparatus 2 Injection water injection apparatus 3 Low frequency pulsation generator for injection water 4 Gas injection apparatus 5 Microbubble generation apparatus 6 Inner pipe 7 Outer pipe 8 Double pipe 9 Pumping pump 10 Jet suction part 11 Catchment tank 12 Press injection Pump 13 Pressure flow control valve 14 Controller 15 Pulsation generator 16 Combustion furnace 17 Separation and recovery device 18 Tank lorry 20 Pumping well 21 Injection well 22 Compressor 24 Carbon dioxide storage tank 25 Casing pipe 26 Insertion pipe 27 Motor 28 Hydraulic cylinder 29 Rubber pipe 30 Plant facility 31 Rotation drive device 34 Fine bubble 35 Slit 40 Tube 41 Injection tube 42 Water pressure meter 43 Thermometer 44 Electrical conductivity meter 45 Measurement code 46 Power cord 47 Suspension wire 48 Concrete 49 Excitation device 50 Deep aquifer 51 Vibrator 52 Storage box 53 Groundwater 4 injection water 55 CO 56 gas-liquid stages 100 carbon capture and storage system of the mixed fluid 57 pressurized water 58 Ground surface 59 magnet 60 coil 61 iron 62 reaction force plate S70~S74 sequestration method of carbon dioxide

Claims (5)

Pumping groundwater from deep aquifers from the pumping well to the ground,
Adding a pulsation pressure of a frequency of 0.5 to 30 Hz generated by a reciprocating motion of a piston of a pulsation generator to an injection well provided so as to reach the deep aquifer;
And forming a gas-liquid mixed fluid by making carbon dioxide into fine bubbles having a diameter of 10 to 50 μm and mixing or dissolving in the injected water at the upper part of the injection well. Underground storage method. The method for underground storage of carbon dioxide according to claim 1, further comprising the step of applying vibration energy to the gas-liquid mixed fluid by a vibration generator installed at the bottom of an injection well.
A pumping device that pumps groundwater from the deep aquifer from the pumping well;
An injected water press-fitting device that feeds the pumped-up groundwater into the injection well as injection water,
A low-frequency pulsation generator having a frequency of 0.5 to 30 Hz, which is provided between the injection water injection device and the injection well and applies pulsation pressure to the injection water;
A gas injection device for sending carbon dioxide from a storage tank to the injection well;
Fine bubbles in which the carbon dioxide is microbubbled to a diameter of 10 to 50 μm at the upper part of the injection well provided to reach the deep aquifer and mixed or dissolved in the injected water to generate a gas-liquid mixed fluid An underground storage system for carbon dioxide, comprising:
4. The carbon dioxide underground storage system according to claim 3, wherein the microbubble generator has an injection pipe for injecting the carbon dioxide obliquely downward, and is constituted by a rotating cylinder.
The underground storage system for carbon dioxide according to claim 3, further comprising a vibration generating device that applies vibration energy to the gas-liquid mixed fluid at a bottom portion of the injection well.

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