JP3141603B2 - Carbon dioxide capture facility - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facility for recovering carbon dioxide, and more particularly to a technique for recovering CO ₂ gas containing activated carbon.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open No.
-186199 and JP-A-4-186200 have been proposed. In these techniques, CaCO ₃ is generated by a chemical reaction between CO ₂ gas and Ca (OH) _2, and ¹⁴ C is adsorbed and solidified.

[0003]

However, when ¹⁴ C is adsorbed and solidified, not all of the supplied Ca (OH) ₂ reacts with CO 2 gas to form CaCO ₃ , but unreacted Ca (OH) ₂ is generated. This unreacted Ca
If (OH) ₂ is solidified together with CaCO ₃ , secondary waste of radioactive materials will increase.
In addition, there remains a problem that the generated CaCO ₃ adheres to the reaction vessel wall and gradually increases the radiation dose in the reaction part.

[0004] The present invention effectively solves the above-mentioned problems, and an object of the present invention is to improve the reaction efficiency between Ca (OH) ₂ and CO ₂ . To prevent adhesion by granulating CaCO ₃ . And so on.

[0005]

A plurality of means for solving the above problems are proposed. The first means is to use CO ₂ gas and Ca
(OH) a recovery plant to produce CaCO ₃ by chemical reaction with _2, is caused to vertically rotated by Ca (OH) ₂ is connected to the supply means the entered Ca (OH) ₂ temporarily housed rotating driving source Rotating reaction casing and CO ₂
A hollow rotating shaft connected to a gas supply system and having a plurality of ejection holes for ejecting CO ₂ gas that is inserted into a central portion of the rotating reaction casing and integrally ejected, and connected to the downstream of the rotating reaction casing to discharge CaCO ₃ And a product discharge port. The second means is such that a configuration in which a spiral blade for sending a solid material downstream is integrally disposed on the outer periphery of the hollow rotary shaft is added to the first means.
The third means is such that a hollow casing is rotatably supported and a non-rotating supply casing is disposed between the Ca (OH) ₂ supply means and the rotary reaction casing.
Or the second means. The fourth means includes a structure in which a non-rotational discharge casing having a rotatable hollow shaft and a product discharge opening is disposed downstream of the rotary reaction casing. Or the third means.

[0006]

In the first means, CO ₂ gas and Ca (O
When CaCO3 is produced by a chemical reaction with H) ₂ , the introduced Ca (OH) ₂ is stirred in the rotary reaction casing. Then, the CO ₂ gas ejected from the ejection hole of the hollow rotary shaft causes Ca (O) in the rotary reaction casing.
H) Reacts with ₂ to form CaCO _3, and granulation to increase the size of the particles by continued stirring is achieved. The granulated CaCO ₃ is prevented from adhering by rolling on the inner wall of the rotary reaction casing, and is discharged from the product discharge port. In the second means, in addition to the action of the first means, the spiral blade rotates together with the hollow rotary shaft, and sends out solid matter in the vicinity thereof downstream. Third
In the means of (1), in addition to the action of the first means or the second means, Ca (OH) ₂ fed into the non-rotating supply casing is carried over to the rotating reaction casing in rotation. In the fourth means, the first means,
In addition to the action of the second means or the third means, CaCO _{3 in} a rotationally moving state is fed into the discharge casing, becomes non-rotatable, and is discharged from the product discharge port.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a carbon dioxide recovery facility according to the present invention will be described below with reference to FIGS. In each figure, reference numeral 1 denotes Ca (OH) ₂ supply means,
2 is a rotary drive source, 3 is a rotary reaction casing, 4 is CO ₂
Gas supply system, 5 is a hollow rotary shaft, 6 is a supply casing, 7
Is a discharge casing, 8 is a product discharge port, 9 is CaCO ₃
A treatment system, 10 is an exhaust gas treatment system, 11 is a spiral blade, G is a solid, and S is a support structure.

The details will be described below.
The a (OH) ₂ supply means 1 supplies powdered Ca (OH) ₂ downstream and is connected to a supply casing 6.

The rotary drive source 2 is connected to the hollow rotary shaft 5 via a pair of bearings 2a attached to the supply casing 6 and the discharge casing 7, and is connected to the rotary reaction casing 3 and the hollow rotary shaft. The axis 5 is, for example, 2
It has a speed reducer and the like for vertical rotation as shown by arrows in FIGS. 1 and 2 at a low speed of about 10 times.

The rotary reaction casing 3 is formed in a cylindrical shape, and both ends of the rotary reaction casing 3 are connected to the inside of the supply casing 6 and the discharge casing 7 by a disc or the like, and the downstream side is, for example, 100 mm. It is integrally attached to the hollow rotary shaft 5 in a state of being inclined down by 2 to 4 minutes. In the example of FIG. 2, a disk 3 a is integrally attached near the downstream end of the rotary reaction casing 3, and a plurality of through holes 3 b for sending the solid matter G into the discharge casing 7 are formed in the disk 3 a. On the downstream end surface of the rotary reaction casing 3, a ring-shaped rubber seal 3 c sliding in the circumferential direction with respect to the inner peripheral surface of the discharge casing 7.
Is attached. Further, in the example of FIG.
Between the rotating casing 3 and the rotating reaction casing 3 so as to be rotatable while supporting the weight of the rotating casing 3.
d is arranged.

In the CO ₂ gas supply system 4, ¹⁴ C
A gas to be treated in a state where nuclides are converted into CO ₂ gas or the like is supplied under pressure in a pressurized state, and is a rotary for connecting the non-rotating pipe 4 a and the rotating hollow rotary shaft 5. And a joint 4b.

As shown in FIGS. 1 and 2, the hollow rotary shaft 5 is located at the center of rotation of the rotary reaction casing 3 and is in communication with the pipe 4a of the CO ₂ gas supply system 4. 5a and a plurality of ejection holes 5b for ejecting the CO ₂ gas supplied to the tube hole 5a. In the example of FIG. 2, the disk 3a is connected to the rotary drive source 2 shown in FIG. 1 by the drive shaft 2b.

In the supply casing 6, as shown in FIG. 1, a hopper 6a connected to the Ca (OH) ₂ supply means 1 and a supply port 6b for dropping Ca (OH) ₂ from the hopper 6a. And

In the discharge casing 7, Ca
A product outlet 8 for connecting to a CO ₃ treatment system 9 is provided, and an exhaust gas treatment system 10 is connected to the upper part. As shown in FIG. 2, a seal ring 7 a made of metal or the like for maintaining airtightness is provided between the rotary reaction casing 3 and the discharge casing 7. And a spring 7b for bringing the spring 7 into close contact with the spring 7. In addition, 7c is a gas outlet.

The product discharge port 8 is disposed below the discharge casing 7 and discharges solid matter G such as CaCO ₃ sent into the discharge casing 7 to the CaCO ₃ treatment system 9. .

In the CaCO ₃ treatment system 9, as shown in FIG.
Solid G mixed with aCO ₃ and unreacted Ca (OH) ₂
, And a separation or solidification treatment is applied.

The exhaust gas treatment system 10 is connected to a gas outlet 7c of the discharge casing 7, and is provided with CO ₂ gas or Ca (OH) ₂
A so-called off-gas, such as air or a gas generated during a chemical reaction, which is contained in advance, is supplied to perform necessary processing such as removal of radioactive substances.

As shown in FIGS. 1 and 2, the spiral blade 11 is formed as a spiral projection integrally formed on the outer periphery of the hollow rotary shaft 5, and rotates the surrounding solid matter G in the downstream direction during the rotation. Arranged to be sent out.

In the thus configured carbon dioxide recovery equipment, the Ca (OH) ₂ is supplied through the supply casing 6 by operating the Ca (OH) ₂ supply means 1 and the CO ₂ gas supply system 4. Then, the CO ₂ gas is fed into the rotary reaction casing 3 via the rotary joint 4b, and is then jetted into the rotary reaction casing 3 from each jetting hole 5b.

The Ca fed into the supply casing 6
(OH) ₂ is temporarily stored, and when the rotary reaction casing 3 is in a rotating state by the operation of the rotary drive source 2, the solid matter G is formed by the pressure difference between the supply casing 6 and the rotary reaction casing 3. It is sent to the rotating reaction casing 3 in a rotating state.

When the rotary reaction casing 3 is in a rotating state, the solid G in contact with the inner wall of the rotary reaction casing 3 is lifted to an upper position by frictional contact, and is stirred to fall down. The reaction between CO ₂ gas and Ca (OH) ₂ is promoted. At this time, CaCO ₃ generated by the chemical reaction is supplied to the rotary reaction casing 3.
Rolling on the inner wall surface of the solid material G and the use of reaction heat generated inside the rotary reaction casing 3 gradually increase the size of the solid G particles.

The spiral blade 11 and the hollow rotary shaft 5
Are rotated, the solid matter G located in the rotation range of the spiral blade 11 and the solid matter G dropped by the rotary reaction casing 3 are gradually sent downstream by the spiral blade 11, and the rotary reaction casing By reducing the amount of solids G in the vicinity of the upstream of the rotary reaction casing 3, the movement of the solids G from the supply casing 6 to the rotary reaction casing 3 is facilitated, and the solid G in the vicinity of the downstream of the rotary reaction casing 3 is reduced. To the inside of the non-rotating discharge casing 7 from the through hole 3b of the disc 3a,
It is discharged as indicated by the arrow in FIG. The discharged solid matter G is sent to the CaCO ₃ treatment system 9 via the product discharge port 8, and required processing such as separation processing and solidification processing is performed as described above.

[Other Embodiments] In the carbon dioxide recovery equipment according to the present invention, the following technology can be adopted instead of the embodiment. a) To make slits and slit holes in the disk 3a. b) The spiral blade 11 has a propeller shape divided in the circumferential direction. c) The number and structure of the support rollers 3d of the rotary reaction casing 3 are arbitrary.

[0024]

According to the carbon dioxide recovery equipment of the present invention, the following effects can be obtained. (1) In the rotating reaction casing, the position where solids are lifted and dropped along with the vertical rotation is replaced and agitated, so that the contact area and the number of contacts during the reaction are increased, and CO ₂ gas is reduced to CaCO _{2. The} solidification of ₃ can be promoted. (2) The solid material is rolled along the inner wall surface along with the vertical rotation of the rotating reaction casing, thereby increasing the particle size and weight by promoting streamlining, and reducing the amount of solid matter attached to the inner wall surface. it can. (3) By dispersing the CO ₂ gas into a plurality of portions from the ejection holes of the hollow rotary shaft, the gas dispersibility can be increased and the solidification reaction efficiency can be improved. (4) By arranging the spiral blades on the outer periphery of the hollow rotary shaft, even when the solids move to the vicinity of the center of rotation with the rotation of the rotary reaction casing, the solids can be smoothly sent downstream. . (5) Ca (OH) ₂ is fed into the rotating reaction casing via the non-rotating supply casing, thereby facilitating the supply of Ca (OH) ₂ and simplifying the support structure of the rotating reaction casing. Can be planned. (6) The solids from the rotating reaction casing are fed to and discharged from the non-rotating discharge casing, thereby simplifying the support structure of the rotating reaction casing and facilitating the transfer and processing of the discharged solids. be able to.

[Brief description of the drawings]

FIG. 1 is a partially sectional front view showing an embodiment of a carbon dioxide recovery facility according to the present invention.

FIG. 2 is a front sectional view showing a connection portion between a rotary reaction casing and a discharge casing of FIG. 1;

FIG. 3 is a cross-sectional view showing a rotary reaction casing and a disk part of FIG. 2;

FIG. 4 is a side view showing a concept of a support structure of the rotary reaction casing of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ca (OH) ₂ supply means 2 Rotation drive source 2a Bearing 2b Drive shaft 3 Rotation reaction casing 3a Disk 3b Through hole 3c Rubber seal 3d Supporting roller 4 CO ₂ gas supply system 4a Pipe 4b Rotary joint 5 Hollow rotation shaft 5a Tube hole 5b Spouting hole 6 Supply casing 6a Hopper 6b Supply port 7 Discharge casing 7a Seal ring 7b Spring 7c Gas discharge port 8 Product discharge port 9 CaCO ₃ treatment system 10 Exhaust gas treatment system 11 Spiral blade G Solid material S Support structure

Claims (4)

(57) [Claims] 1. A recovery facility for producing CaCO ₃ by a chemical reaction between CO ₂ gas and Ca (OH) ₂ ,
Ca (O) connected to the a (OH) ₂ supply means
H) A rotary reaction casing temporarily containing 2 and vertically rotated by a rotary drive source, and a plurality of jets connected to a CO ₂ gas supply system and inserted into the central portion of the rotary reaction casing in an integrally rotating state to jet CO ₂ gas. A hollow rotary shaft with a hole, and a Ca connected downstream of the rotary reaction casing.
A carbon dioxide recovery facility, comprising: a product outlet for discharging CO ₃ . 2. The carbon dioxide recovery facility according to claim 1, wherein a spiral blade for sending a solid substance downstream is integrally disposed on an outer periphery of the hollow rotary shaft. 3. A non-rotatable supply casing, which rotatably supports a hollow rotary shaft and is provided between the Ca (OH) ₂ supply means and the rotary reaction casing. 2. The carbon dioxide recovery equipment according to 2. 4. A non-rotating discharge casing, which rotatably supports a hollow rotary shaft and has a product discharge opening, is disposed downstream of the rotary reaction casing. Or the carbon dioxide recovery equipment according to 3.