JP2993348B2 - Method for treating carbon dioxide, method for treating exhaust gas containing carbon dioxide, and its treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating carbon dioxide, which is an exhaust gas generated by a thermal power source such as a power plant or a garbage incinerator, a method for treating an exhaust gas containing carbon dioxide, and a facility for treating the same.

[0002]

2. Description of the Related Art Fossil fuels such as coal, oil or natural gas have long been used as the most excellent energy source for industrial activities and human life. At present, even the indispensable electricity is mainly supplied by the thermal power obtained by burning this fossil fuel. Due to the combustion of these fossil fuels, a considerable amount of carbon dioxide is generated and discharged as it is into the atmosphere as exhaust gas. On the other hand, from a thermal power source such as a garbage incineration facility, a large amount of carbon dioxide is contained in exhaust gas generated by incineration, and is similarly discharged to the atmosphere. Further, even if natural gas that can obtain the same energy is used, although the amount of carbon dioxide generated is smaller than that of petroleum or coal, carbon dioxide is generated and discharged into the atmosphere as described above.

[0003]

By the way, the energy demand in the world is increasing year by year, and the amount of carbon dioxide emitted is also increasing accordingly. On the other hand, deforestation is progressing due to over-cutting of timber and the like, which makes it impossible for plants on the earth to keep up with the carbon dioxide treatment capacity. For this reason, carbon dioxide
Even if emitted into the atmosphere, they remain without being circulated to the natural environment, causing problems such as global warming. On the other hand, at present, no effective energy source has been available to replace fossil fuels, and it is certain that fossil fuels such as oil, coal or natural gas will continue to be used. For this reason, there has been a problem that if the exhaust gas containing carbon dioxide is continuously discharged into the atmosphere, the global warming will further progress.

[0004] Exhaust gas generated from a thermal power source such as a thermal power plant or a garbage incineration facility contains residual waste heat, and it has been desired to reuse this waste heat.

On the other hand, it has been desired to recycle concrete waste that has become unnecessary as industrial waste caused by the demolition of buildings and the like.

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to be able to process carbon dioxide generated by combustion or the like without discharging it to the atmosphere. Another object of the present invention is to provide a method for treating carbon dioxide, a method for treating an exhaust gas containing carbon dioxide, and a facility for treating the carbon dioxide, which can also achieve reuse of waste heat and effective use of concrete waste.

[0007]

In order to solve the above problems, in the present invention, carbon dioxide is pressurized and dissolved in water to produce carbonated water, and then the carbonated water is brought into contact with a concrete material. It is characterized by generating carbonate.

Further, the contact layer formed by pressurizing an exhaust gas containing carbon dioxide generated by a thermal power source, dissolving the exhaust gas in purified water to generate carbonated water, and then depositing a concrete material to form a contact layer. Carbonated water is brought into contact with the concrete material to generate carbonate, and then residual water containing calcium ions and carbonate ions remaining after the contact is stored in a storage tank, and the stored water is supplied to a bath facility. And

[0009] Further, an exhaust gas supply system for supplying exhaust gas containing carbon dioxide generated by a thermal power source, a water purification device for drawing in and purifying water from a water source, and a pressurizing exhaust gas supplied from the exhaust gas supply system. A pressurizing means for dissolving the exhaust gas in purified water supplied from the water purification device, and a contact layer provided downstream of the pressurizing means and formed by depositing a concrete material therein, A carbon dioxide fixing tank in which the carbonated water generated by the pressurizing means is brought into contact with the concrete material; and a storage tank connected to the fixing tank and for storing residual water containing calcium ions and carbonate ions discharged therefrom. And supply means for supplying the stored water in the storage tank to the bath facility.

Further, the exhaust gas supply system is provided with a waste heat recovery means for recovering waste heat.

Further, the concrete material is used concrete waste.

[0012]

The operation of the present invention will be described. First, carbon dioxide is dissolved by pressurizing carbon dioxide to produce carbonated water. Next, the carbonated water is brought into contact with the concrete material, and causes a chemical reaction with alkali ions such as calcium ions in the concrete to generate carbonate. As described above, since carbon dioxide can be completely replaced with another substance as a carbonate, it can be treated without discharging carbon dioxide to the atmosphere.

Further, the exhaust gas containing carbon dioxide generated by the thermal power source is pressurized, the exhaust gas is dissolved in purified water to generate carbonated water, and then a concrete material is deposited on the contact layer. When carbonated water is brought into contact with the concrete material, the carbonated water causes a chemical reaction with alkali ions such as calcium ions in the concrete, and carbonates such as calcium carbonate are generated. From this, it is possible to treat carbon dioxide in exhaust gas without discharging it to the atmosphere. Then, the residual water after the contact contains calcium ions and carbonate ions, which are stored in a storage tank, and the stored water is supplied to a bath facility to use the stored water as bath water. In this case, a hot spring effect can be obtained.

Further, an exhaust gas supply system for supplying exhaust gas containing carbon dioxide generated from a thermal power source, a water purification device for drawing in and purifying water from a water source, and pressurizing exhaust gas supplied from the exhaust gas supply system. And pressurizing means for dissolving the exhaust gas in purified water supplied from the water purification device, so that carbonated water can be generated from the exhaust gas generated by the thermal power source. Further, a contact layer is provided on the downstream side of the pressurizing means and formed by depositing a concrete material therein, so that the carbonated water generated by the pressurizing means can be brought into contact with the concrete material. By providing the fixed tank, the generated carbonated water can be brought into contact with the concrete material to generate a carbonate such as calcium carbonate. From this, it is possible to treat carbon dioxide without discharging it to the atmosphere. Also, a storage tank connected to the dioxide fixation tank, for storing residual water containing calcium ions and carbonate ions discharged therefrom,
Supply means for supplying the stored water in the storage tank to the bathhouse facility, by storing residual water containing calcium ions and carbonate ions discharged from the carbon dioxide fixed tank, and using the stored water as a bath water If it is used, a hot spring effect can be obtained.

Further, by providing a waste heat recovery means for recovering waste heat in the exhaust gas supply system, the remaining waste heat of the exhaust gas can be recovered and used as a heat source for external equipment. . For this reason, if this waste heat is provided to the stored water supplied to the bath facility, it can be supplied as bath water.

Further, since the concrete material is used concrete waste, a large amount of concrete waste material generated in the demolition of buildings can be reused without being discarded as industrial waste.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows an energy saving system called a cogeneration system that incorporates an exhaust gas treatment facility containing carbon dioxide. In this cogeneration system 2, a gas turbine power generator 6 is installed along with the building 4 and supplies electric energy necessary for human life and industrial activities inside the building 4. The gas turbine power generator 6 generates electric power by a thermal power obtained by burning natural gas. In burning this natural gas, [CH ₄ + 2O ₂ → CO ₂
+ 2H ₂ O], the exhaust gas contains carbon dioxide (CO ₂ ). This natural gas is widely used as a very useful fossil fuel because it can extract more energy than petroleum or coal, despite the small amount of carbon dioxide generated. Here, in the gas turbine power generation device 6, instead of natural gas, thermal power may be obtained from fossil fuels such as petroleum and coal, or thermal power may be obtained from incineration heat of combustible materials such as garbage. good.

Further, an exhaust gas treatment facility 7 is provided for treating the exhaust gas generated in the gas turbine power generator 6. The exhaust gas treatment facility 7 mainly includes a carbon dioxide treatment unit 8 for treating carbon dioxide in exhaust gas and a waste heat recovery unit 10 for collecting residual waste heat in the exhaust gas.
First, the carbon dioxide processing unit 8 will be described. FIG.
FIG. 2 is a schematic configuration diagram illustrating a main part of the carbon dioxide processing unit 8. In the carbon dioxide processing unit 8, the exhaust gas is pressurized,
The carbon dioxide contained therein is dissolved in water to generate carbonated water, and the generated carbonated water is brought into contact with a concrete material to generate carbonate. In order to implement this, the main components are an exhaust gas supply system 12 connected to the gas turbine power generation device 6 and extracting and supplying exhaust gas containing carbon dioxide therefrom, and a water purification device 14 that draws water from a water source and purifies it. A pressurizing cylinder 16 as pressurizing means for pressurizing exhaust gas and dissolving carbon dioxide in purified water from the water purification device 14 to generate carbonated water; And a carbon dioxide fixation tank 22 having a contact layer 20 formed by depositing 18.

The exhaust gas supply system 12 is interposed between the gas turbine generator 6 and the pressurizing cylinder 16. In the exhaust gas supply system 12, the waste heat boiler 1 of the waste heat recovery unit 10 is provided.
1 is provided. The exhaust gas generated in the gas turbine power generator 6 is sequentially supplied to the pressurized cylinder 16 via the waste heat boiler 11 through the exhaust gas supply system 12. Further, the water purification device 14 is connected to a river 14 a or the like as a water source, draws water therefrom to purify the water, and supplies the purified water to the pressurized cylinder 16.

The pressurized cylinder 16 has an exhaust gas supply system 1
2 is connected, exhaust gas is supplied, and the water purification device 14 is connected to supply purified water. These exhaust gas and purified water are both introduced into the cylinder chamber 16a and pressurized. By this pressure,
Carbon dioxide contained in the exhaust gas is forcibly dissolved in the purified water to generate carbonated water. This reaction formula is [CO ₂ + H ₂ O → H ₂ CO ₃ ]. The carbonated water thus generated is supplied to the cylinder chamber 16a.
It is sent from inside to the carbon dioxide fixing tank 22.

The carbon dioxide fixing tank 22 has a contact layer 20 for bringing carbonated water into contact with the concrete material 18.
4 and an accumulation tank 26 for accumulating carbonates such as calcium carbonate generated in the infiltration tank 24.
First, the permeation tank 24 will be described.
A watering nozzle 24a for watering the carbonated water sent from the pressurizing cylinder 16 downward is provided on the upper part of the tank so that the carbonated water is sprayed throughout the permeation tank 24. Has become. On the other hand, at the bottom of the infiltration tank 24, a flow hole 24b that can flow to the accumulation tank 26 is formed. An inclined portion 24c is formed on the bottom surface of the permeation tank 24 such that the flow hole 24b is on the downstream side. Inside the infiltration tank 24, a contact layer 20 formed by depositing a concrete material 18 that comes into contact with carbonated water is provided. Since the concrete material 18 is brought into contact with carbonated water, it is preferable that the concrete material 18 be crushed and formed into strips in order to increase the contact area. Especially,
As the concrete material 18, used concrete waste originally discarded as industrial waste due to demolition of a building or the like is very suitable. For this reason, the carbonated water sent from the pressurized cylinder 16 is discharged from the watering nozzle 24 a provided on the upper part of the permeation tank 24, and is sprayed on the contact layer 20. The sprayed carbonated water travels on the surface of the concrete material 18 of the contact layer 20 and flows down to the bottom of the infiltration tank 24. Here, the slightly acidic carbonated water comes into contact with the concrete material 18 while flowing down, and chemically ^reacts with calcium ions (Ca ²⁺ ) of calcium hydroxide (CaCO ₃ ) contained in the concrete material 18. A reaction occurs, and a carbonate such as calcium carbonate (CaCO ₃ ) is generated. This chemical reaction is [H ₂ CO ₃ +
Ca (OH) ₂ → CaCO ₃ + 2H ₂ O]. The calcium carbonate thus generated flows down together with the carbonated water. Calcium carbonate is generated one after another by the flow of the carbonated water, and calcium ions (Ca ²⁺ ) and carbonate ions (CO ₃ ²⁻ ) remaining by the reaction remain in the residual water reaching the bottom of the permeation tank 24. ). When this residual water reaches the bottom of the permeation tank 24, it is collected in the flow hole 24b down the inclined portion 24c,
It flows out into the accumulation tank 26.

Then, as described above, the residual water flows into the accumulation tank 26 from the permeation tank 24 through the circulation hole 24b. The inflowing residual water is temporarily stored in the accumulation tank 26, whereby calcium carbonate contained therein is precipitated and removed, and the residual water containing remaining calcium ions and carbonate ions is stored. Water is sent to the tank 30. In the present embodiment, a partition wall 26a is formed in the accumulation tank 26, and a plurality of sedimentation tanks 27a to 27
c has been defined. In FIG. 2, the first sedimentation tank 27a, the second sedimentation tank 27
b, three settling tanks 27a to 27c of a third settling tank 27c are formed. The partition wall 26 that defines these sections
a is set so that its height is lower than the position where the flow hole 24b is formed so as not to flow backward to the permeation tank 24 side, and each partition wall 26a is stepwise along the downstream direction of the residual water, It is formed to be lower. Flow hole 24b
The residual water flowing from the first settling tank first flows down into the first settling tank 27a and is temporarily stored. Then, the calcium carbonate contained in the residual water sinks by its own weight, and precipitates as a precipitate 28 at the bottom of the first settling tank 27a. When the inside of the first sedimentation tank 27a is filled with residual water, the outflow thereof is regulated by a partition wall 26a formed between the first sedimentation tank 27a and the second sedimentation tank 27b. The supernatant water containing calcium ions and carbonate ions flows out into the second settling tank 27b. In this way, the supernatant water flowing into the second settling tank 27b is separated from the partition wall 26a between the second settling tank 27b and the third settling tank 27c.
Is formed lower than that between the first settling tank 27a and the second settling tank 27b, and therefore does not flow back into the first settling tank 27c. Further, when the supernatant water is stored in the second settling tank 27b, the supernatant water in the second settling tank 27b is changed to the third settling tank 27c as in the first settling tank 27a.
Leaks to Thereby, the residual water flowing into the accumulation tank 26 is transferred from the first precipitation tank 27a to the second precipitation tank 27a.
b, as it moves downstream to the third settling tank 27c,
Calcium carbonate is removed. The supernatant water of the third settling tank 27c located at the most downstream contains calcium ions and carbonate ions, and becomes residual water containing almost no calcium carbonate. It is sent to the storage tank 30.

The residual water containing calcium ions and carbonate ions sent from the accumulation tank 26 of the carbon dioxide fixing tank 22 is temporarily stored in the storage tank 30. This storage tank 30 has an unused energy source 3 such as an external factory.
1 is connected, and the warm waste water discharged from it is circulated and supplied to warm the stored water. And this storage tank 3
To 0, a hot water storage tank 32 and a supply system 33 thereof are connected as supply means for supplying the stored water to a bath facility 34. The stored water in the storage tank 30 is
Are sequentially supplied, heated, and temporarily stored as hot water. Further, the hot water is supplied as bath water to a bath facility 34 such as a bath as needed. In this heating, the waste heat recovery unit 10 provided with the carbon dioxide processing unit 8 is connected to the hot water storage tank 32. The waste heat recovery unit 10 is provided in the exhaust gas supply system 12 and has a waste heat boiler 11 as waste heat recovery means, and a steam circulation system provided between the waste heat boiler 11 and the hot water storage tank 32. 35. Waste heat boiler 11
Recovers the remaining waste heat from the exhaust gas flowing in the exhaust gas supply system 12 and converts the waste heat into steam in the steam circulation system 35. The steam circulation system 35 is connected to the hot water storage tank 32 to feed the steam therein, and heats the water stored in the hot water storage tank 32 with the steam. Further, the steam circulation system 35 is connected to a cooling and heating facility in the building 4 and the sent steam is used as a heat source.

The bath water used in the bath facility 34 is returned to a water source such as the river 14a as domestic wastewater through a water treatment facility (not shown). At this time, the drainage of the bathhouse may be dropped at the water pagoda tower 36 interposed between the bathhouse facility 34 and the river 14a so as to produce a beautiful tone.
In addition, regarding the carbon dioxide generated in the building 4, the ventilation port 38 is formed between the room and the indoor botanical garden 40 provided outside the building 4, and the carbon dioxide is generated by the indoor botanical garden 4.
It may be sent to 0 for processing.

From the above, the operation of the present embodiment will be described.
The exhaust gas generated in the gas turbine power generator 6 is supplied to the pressurized cylinder 16 by the exhaust gas supply system 12, and purified water purified by the water purification device 14 is supplied to the pressurized cylinder 16. Then, the supplied exhaust gas and purified water are introduced into the cylinder chamber 16a of the pressurizing cylinder 16 and pressurized. By this pressurization, the carbon dioxide contained in the exhaust gas is dissolved in the purified water to generate carbonated water. The carbonated water thus generated is sent from the pressurized cylinder 16 to the carbon dioxide fixing tank 22.
Next, in the infiltration tank 24, the sent carbonated water is
It is brought into contact with the concrete material 18 of the contact layer 20 formed thereon, and causes a chemical reaction with alkali ions such as calcium ions contained in the concrete to generate carbonates such as calcium carbonate. In this way, the carbon dioxide can be replaced by a completely different substance as a carbonate and can be treated without being released to the atmosphere. From this, it is possible to suppress an increase in the amount of carbon dioxide in the atmosphere and to protect the global environment.

When the carbonated water is brought into contact with the concrete material 18 and the remaining water flows into the collecting tank 26, the calcium carbonate contained therein is removed from the sedimentation tank 27a.
~ 27c to remove calcium carbonate from residual water. Next, the residual water containing the calcium ions and the carbonate ions is sent to the storage tank 30 to be temporarily stored. Then, the stored water is heated by an external unused energy source 31, sent to a hot water storage tank 32, heated, and temporarily stored as hot water. Further, the hot water is supplied as bath water to a bath facility 34 such as a bath as needed. Since calcium ions and carbonate ions are retained in the residual water serving as bath water, a hot spring effect can be obtained.

If the concrete material 18 is used, which is crushed and formed into strips, such as concrete chips, the contact area between the carbonated water and the concrete material 18 can be increased. A large amount of carbon dioxide can be processed by causing a chemical reaction.

Further, a waste heat boiler 11 as waste heat recovery means is provided in the exhaust gas supply system 12 to recover residual waste heat from the exhaust gas generated from the gas turbine power generator 6. Thereby, the collected waste heat can be used as a heat source of the cooling and heating equipment in the building 4 and the hot water storage tank 3
In 2, if it is used as a heating source of stored water, hot water can be generated without taking heating means such as a water heater. From this, energy saving can be achieved by using the remaining waste heat of the exhaust gas as an external heat source instead of radiating the heat as it is.

The concrete material 18 in the infiltration tank 24
By using used concrete waste generated by demolition of a building or the like, the waste can be reused without being discarded as industrial waste.

Further, the water necessary for generating the carbonated water is provided from the water source such as the river 14a by providing the water purification device 14, and the waste water used as the bath water and the like which is no longer needed is purified. Then, by returning the water to the river 14a or the like again, it is possible to circulate the water so that the natural environment is not affected.

As described above, by arranging this exhaust gas treatment facility in a facility having a thermal heat source such as a thermal power plant or a garbage incineration facility, carbon dioxide in the exhaust gas generated from the heat source is released into the atmosphere. Can be processed without the need.

[0032]

According to the present invention, as described above, according to the present invention, carbon dioxide is dissolved in water to produce carbonated water, and the carbonated water is brought into contact with a concrete material to produce carbonate. Thereby, the carbon dioxide can be fixed as a carbonate, and can be treated without being discharged into the atmosphere. From this, it is possible to suppress an increase in the amount of carbon dioxide in the atmosphere and to protect the global environment.

Also, dissolving exhaust gas containing carbon dioxide generated by a thermal power source into purified water to produce carbonated water, which is brought into contact with concrete material to cause a chemical reaction to produce carbonate. Thereby, the carbon dioxide in the exhaust gas generated from the thermal power source can be fixed as calcium carbonate and can be treated without being discharged into the atmosphere.
For this reason, similarly to the above, by reducing the amount of exhaust gas emitted, it is possible to suppress an increase in the amount of carbon dioxide in the atmosphere and to protect the global environment. In addition, the residual water containing calcium ions and carbonate ions remaining after the contact is stored, and the stored water is supplied to a bathing facility so that a hot spring effect can be obtained if the stored water is used as bath water. It becomes possible.

Also, an exhaust gas supply system for supplying exhaust gas generated from the thermal power source, a water purification device for purifying water from the water source, and a pressurizing means for pressurizing the exhaust gas to dissolve it in purified water to produce carbonated water. And a carbon dioxide fixing tank that is located downstream of the pressurizing means and brings the carbonated water into contact with the concrete material, whereby the carbon dioxide generated by the thermal power source can be fixed as calcium carbonate. . For this reason, similarly to the above, by reducing the amount of exhaust gas containing carbon dioxide, it is possible to suppress an increase in the amount of carbon dioxide in the atmosphere and to protect the global environment. Further, by providing a storage tank connected to the carbon dioxide fixed tank and storing the residual water therein, and a supply means for supplying the stored water in the storage tank to the bath facility, calcium ions and carbonate ions are provided. If the residual water is used as bath water, a hot spring effect can be obtained.

Further, by providing a waste heat recovery means for recovering waste heat in the exhaust gas supply system and recovering the remaining waste heat of the exhaust gas, the waste heat can be used as a heat source for external equipment. Can be achieved. From this, it becomes possible to supply this waste heat to the stored water supplied to the bath facilities and supply it as bath water.

In addition, since the concrete material is used concrete waste, a large amount of concrete waste material generated in the demolition of a building or the like can be reused without being discarded as industrial waste.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of an exhaust gas treatment facility containing carbon dioxide according to the present invention.

FIG. 2 is a schematic configuration diagram illustrating a main part of a carbon dioxide processing unit in FIG. 1;

[Explanation of symbols]

 6 Gas Turbine Generator 7 Exhaust Gas Treatment Equipment 11 Waste Heat Boiler 12 Exhaust Gas Supply System 14 Water Purifier 16 Press Cylinder 18 Concrete Material 20 Contact Layer 22 Carbon Dioxide Fixed Tank 30 Storage Tank 34 Bath Facilities

Continuing on the front page (72) Inventor Seiichiro Shimizu 2-3-3 Kandaji-cho, Chiyoda-ku, Tokyo Tokyo Main Office (72) Inventor Shinichi Yoshimura 2-3-3 Kandaji-cho, Chiyoda-ku, Tokyo Obayashi Corporation Tokyo Main Office (72) Inventor Koji Kawai 2-3-3 Kandaji-cho, Chiyoda-ku, Tokyo Tokyo Main Office Tokyo (72) Inventor Makiko Shimizu 2-3-3, Kandaji-cho, Chiyoda-ku, Tokyo Tokyo Main Office In-house (56) References JP-A-54-96472 (JP, A) JP-A-5-200090 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B01D 53/62 B01D 53 / 34 B01J 19/00

Claims (5)

(57) [Claims] 1. A method for treating carbon dioxide, wherein carbon dioxide is dissolved by pressurizing carbon dioxide to produce carbonated water, and then the carbonated water is brought into contact with a concrete material to produce a carbonate. 2. A contact layer formed by pressurizing an exhaust gas containing carbon dioxide generated by a thermal power source, dissolving the exhaust gas in purified water to generate carbonated water, and then depositing a concrete material. Carbonated water is brought into contact with the concrete material to generate carbonate, and then residual water containing calcium ions and carbonate ions remaining after the contact is stored in a storage tank, and the stored water is supplied to a bath facility. Exhaust gas treatment method containing carbon dioxide. 3. An exhaust gas supply system for supplying an exhaust gas containing carbon dioxide generated by a thermal power source, a water purification device for drawing in and purifying water from a water source, and pressurizing the exhaust gas supplied from the exhaust gas supply system. A pressurizing means for dissolving the exhaust gas in purified water supplied from the water purification device, and a contact layer provided downstream of the pressurizing means and formed by depositing a concrete material therein, A carbon dioxide fixing tank in which the carbonated water generated by the pressurizing means is brought into contact with the concrete material; and a storage tank connected to the fixing tank and for storing residual water containing calcium ions and carbonate ions discharged therefrom. Exhaust gas treatment equipment containing carbon dioxide, comprising: a supply means for supplying water stored in the storage tank to a bath facility. 4. The exhaust gas treatment equipment containing carbon dioxide according to claim 3, wherein a waste heat recovery means for recovering waste heat is provided in the exhaust gas supply system. 5. The exhaust gas treatment facility containing carbon dioxide according to claim 3, wherein the concrete material is used concrete waste.