Co2 immobilizing system

Abstract

To provide a CO2 immobilizing system and a CO2 immobilizing method for determining that CO2 has been sufficiently immobilized to a waste at real time.SOLUTION: A CO2 immobilizing system includes a CO2 supply device, a waste supply device, and a CO2 immobilizing device for reacting a waste supplied by the waste supply device with CO2 supplied by the CO2 supply device, and thereby producing a waste to which CO2 is immobilized, wherein the CO2 immobilizing device incudes means for acquiring a change rate of a CO2 estimated immobilized amount, and brings the waste and the CO2 into contact with each other until the change rate exceeds a predetermined value.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a CO2 fixation system, particularly to a CO2 fixation system for adsorption, landfill or sequestration of CO2 in waste. [Background technology]

[0002] It is known that an increase in the amount of carbon dioxide (hereinafter, "CO2") released into the atmosphere leads to rising temperatures and the occurrence of abnormal weather associated with it. To prevent this, technology is required to suppress CO2 emissions and reduce CO2 in the atmosphere. Patent Document 1 discloses a technology in which a gas to be treated that contains CO2 is brought into contact with a dispersion liquid that contains biomass incineration ash, and CO2 contained in the gas to be treated is adsorbed to the biomass incineration ash to produce a CO2 fixation material. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent application 2020-175318 publication Summary of the Invention [Problem to be solved by the invention]

[0004] However, because actual waste contains various substances, the amount of CO2 that the waste can absorb is not constant. Therefore, when trying to maximize the amount of CO2 immobilized in the waste, the time required for immobilization will differ depending on the waste lot. In addition, making the immobilization time longer than necessary in order to maximize immobilization leads to a decrease in the operating efficiency of the equipment, which is not desirable.

[0005] Therefore, there is a demand for a CO2 fixation system and method that can determine in real time whether CO2 fixation in waste has been sufficient. [Means for solving the problem]

[0006] The CO2 fixation system disclosed herein comprises a CO2 supplying device, a waste supplying device, and a CO2 fixation device that generates waste in which CO2 is fixed by reacting the waste supplied by the waste supplying device with CO2 supplied by the CO2 supplying device, and is characterized in that the CO2 fixation device comprises a means for acquiring a rate of change of an estimated fixed amount of CO2, and brings the waste and CO2 into contact with each other until the rate of change exceeds a predetermined value. Effect of the Invention

[0007] According to the present disclosure, it is possible to determine in real time whether CO2 has been sufficiently fixed in waste. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a CO2 fixation system according to the present disclosure. [Diagram 2] FIG. 2 is a diagram showing the operation of the CO2 fixation system according to the present disclosure. [Diagram 3] FIG. 2 is a diagram showing the operation of the CO2 fixation system according to the present disclosure. [Figure 4] FIG. 2 is a diagram showing the operation of the CO2 fixation system according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a CO2 fixation system according to one embodiment of the present invention will be described. The drawings used in this embodiment are intended to explain the configuration, arrangement, function, action, and effect of the present invention, and are not intended to limit the specific configuration of the present invention.

[0010] [Outline of the CO2 fixation system] Fig. 1 is a schematic diagram of a CO2 fixation system according to the present disclosure. In Fig. 1, the CO2 fixation system includes an incineration or combustion device, a dust treatment device, a waste supply device, a CO2 supply device, and a CO2 fixation device.

[0011] A CO2 fixation system is a system that fixes CO2 in waste. Waste includes combustible waste that is incinerated and non-combustible waste that is not incinerated. Combustible waste includes waste plastics, rubber scraps, metal scraps, glass scraps, concrete scraps, ceramic scraps, sludge, waste oil, waste acid, waste alkali, paper scraps, wood scraps, textile scraps, animal and plant residues, solid animal waste, animal manure, flammable waste oil, strong acid, strong alkali, etc. Non-combustible waste includes glass scraps, ceramic scraps, stones, sand, residual soil, etc. These wastes are just examples, and waste includes waste classified as general industrial waste and waste classified as specially controlled industrial waste.

[0012] [Incineration device] In the incineration device, combustible waste is incinerated, and exhaust gas and combustion by-products are generated. In one embodiment, a stoker furnace or a rotary kiln furnace is used for incineration. A stoker furnace is an incinerator that dries and heats waste on a fire grate (stoker), and burns it while stirring and moving it. A rotary kiln furnace is a rotating furnace that stirs and incinerates waste by slow rotation. Incineration at 800°C or higher in a combined incinerator with a rotary kiln furnace can be an environmentally friendly incineration process. High-calorie waste such as waste oil and waste plastic, and harmful substances such as cyanide compounds are incinerated at 900-1000°C in a rotary kiln furnace. The incineration device can be a combustion device, and the combustion device performs thermal power generation, biomass combustion power generation, etc. After incineration, the bottom ash and cinders fall into the water below the furnace, are carried out by an ash discharge conveyor, and are supplied to a CO2 fixation device. Hereinafter, the main ash and cinders, which are combustion by-products, will be referred to uniformly as "bottom ash."

[0013] [Soot and dust treatment equipment] In the dust treatment device, activated carbon and slaked lime are sprayed into the exhaust gas. In other words, calcium (slaked lime) is added to the exhaust gas. The activated carbon adsorbs dioxins, and the slaked lime absorbs acid gases (hydrogen chloride, SO X The amount of chemicals is controlled by a laser type hydrogen chloride concentration meter (not shown) installed in the flue.

[0014] Furthermore, in the soot treatment device, soot is separated from the exhaust gas. In the soot treatment, a bag filter and a chelating agent applying means are further used. The exhaust gas passes through the bag filter, and the soot is separated from the exhaust gas. The soot separated by the bag filter is a powder containing lead and the like, and it is necessary to immobilize the heavy metals contained in the soot. Therefore, the soot is given moisture and a chelating agent (heavy metal fixing agent), and the heavy metals are immobilized. The soot then proceeds to CO2 immobilization.

[0015] In this disclosure, the dust treatment uses two bag filters, each of which has 490 cylindrical filter cloths with a diameter of 20 cm and a length of 6 m, but is not limited to this. The fly ash (dust) separated in the dust supply device is supplied to the CO2 fixation device.

[0016] [Waste supply device] The waste feeder feeds non-incinerated waste to the CO2 fixation device. The waste may be non-combustible waste. Preferably, the waste is crushed and fed. The waste feeder may include a shredder used to crush the non-combustible waste into small pieces, a grinder used to break the non-combustible waste into fine powder, and the like.

[0017] [CO2 supply device] The CO2 supplying device includes a separation means for separating CO2, a compression means, and a storage means. In the CO2 supplying device, CO2 is separated from the flue gas from which soot has been removed. The separation means separates CO2 from the flue gas using, for example, a chemical absorption method, a physical absorption method, a physical adsorption method, a membrane separation method, a cryogenic separation method, or the like.

[0018] In the CO2 supply device, the CO2 is concentrated to a concentration higher than that present in the atmosphere and is supplied to the CO2 fixation device. In the CO2 supply, a compression means and a storage means are used.

[0019] The compression means is a CO2 compressor. The CO2 compressor is constructed of high strength steel, stainless steel, etc. to handle the high pressures of CO2. The storage means can be a gas cylinder.

[0020] [CO2 fixation device] In one embodiment, the CO2 fixation apparatus includes a chamber, a kneading means, a first gas supplying means, and a measuring means.

[0021] The chamber is a sealable container for receiving the waste, CO2, and the first gas, and is provided with a kneading means. The kneading means is a means for mixing the waste and CO2, and is provided with, for example, a kneading propeller and a drive motor. The kneading means may also be a means for rotating the chamber itself to mix the contents.

[0022] The first gas supply means supplies a first gas into the chamber. The first gas is air or a gas containing a gas other than carbon dioxide, and the gas containing a gas other than carbon dioxide includes an inert gas such as argon gas or N2 gas.

[0023] The measuring means includes a means for acquiring a rate of change of the estimated amount of fixed CO2. The rate of change of the estimated amount of fixed CO2 is acquired by measuring the pressure in the chamber or the CO2 concentration in the chamber. From the measurement result, it is determined whether or not the fixation of CO2 into the waste has been sufficiently performed.

[0024] (CO2 fixation) In one embodiment, the bottom ash supplied by the incineration device, the dust supplied by the dust treatment device, the waste supplied by the waste supply device, and the CO2 supplied by the CO2 supply device are supplied to the CO2 fixation device. The CO2 fixation device may further include a means for adding an alkaline earth metal-containing material such as calcium (Ca) and / or magnesium (Mg). The CO2 fixation device may further include a means for adding moisture.

[0025] The CO2 fixation device reacts bottom ash, soot, non-combustible waste, and CO2 by kneading them together to produce a CO2 fixation material in which CO2 is fixed. The CO2 is fixed by binding with alkaline earth metals such as calcium (Ca) and / or magnesium (Mg) contained in the bottom ash, soot, and non-combustible waste.

[0026] In one embodiment, the CO2 concentration in the kneading means can be adjusted to any value, for example, 50% by supplying a first gas. The waste and CO2 are sealed in the kneading means and contact each other, and as the CO2 is immobilized in the waste, the CO2 concentration in the kneading means decreases. The first gas is supplied into the kneading means by the first gas supplying means to prevent a pressure drop in the kneading means. Therefore, as the immobilization of CO2 in the waste progresses, the CO2 concentration in the kneading means decreases.

[0027] The decrease in CO2 concentration becomes slower over time, and when the slope of the CO2 concentration change exceeds a set value (e.g., -1% / hour), it is determined that CO2 fixation has been sufficient.

[0028] In addition, the amount of CO2 immobilized in the waste can be specified by measuring the CO2 concentration or the first gas concentration. In addition, the amount of decrease in CO2 and the first gas can be measured to improve the measurement accuracy. The CO2 immobilization device may be equipped with multiple gas supply means.

[0029] Example 1 2 shows the operation of the CO2 fixation system 110 in Example 1. The CO2 fixation system 110 includes an incineration device 3, a dust treatment device 5, a CO2 supply device 9, a waste material supply device 11, a first gas supply device 13, a CO2 fixation device 15, a CO2 concentration meter 17, and valves 1-3.

[0030] The waste incinerated by the incineration device 3 is separated into bottom ash and exhaust gas. The exhaust gas is separated from the soot by the soot treatment device 5, and the bottom ash and soot are supplied to the CO2 fixation device 15.

[0031] The CO2 is further separated from the exhaust gas by the CO2 supplying device 9. The CO2 is concentrated by the CO2 supplying device 9 and supplied to the CO2 fixation device 15. The non-combustible waste is supplied to the CO2 fixation device 15 by the waste supplying device 11.

[0032] In one embodiment, CO2 fixation is carried out by adjusting the waste material, CO2, and the first gas according to the following steps 1-8, which are exemplary and do not specify detailed operations.

[0033] [Table 1]

[0034] As shown in Table 1, the waste and CO2 are sealed and mixed in the CO2 fixation device 15. A first gas is supplied in response to the pressure drop caused by CO2 fixation in the CO2 fixation device 15. This causes the CO2 concentration in the kneading means 16 to decrease, and the concentration change gradually becomes slower over time. When the slope of the CO2 concentration change exceeds a set value (e.g., -1% / hour), it is determined that CO2 fixation has been performed sufficiently. The gas in the kneading means 16 is released to the atmosphere through the chimney, and the waste with CO2 fixed is discharged from the kneading means 16.

[0035] By carrying out CO2 fixation in this manner, it is possible to use changes in CO2 concentration to determine in real time whether CO2 fixation in the waste has been sufficient.

[0036] Example 2 3 shows the operation of the CO2 fixation system 120 in Example 2. In this embodiment, the CO2 fixation system 120 further includes a buffer tank 19, a pressure gauge 21, and a valve 4, as compared with the CO2 fixation system 110 in Example 1. The buffer tank 19 communicates with the inlet and outlet of the CO2 fixation device 15. The pressure gauge 21 is disposed in the CO2 fixation device 15.

[0037] In one embodiment, CO2 fixation is carried out by steps 1-8 below.

[0038] [Table 2]

[0039] As shown in Table 2, the waste and CO2 are sealed in the CO2 fixation device 15 and kneaded. The first gas is supplied in response to the pressure drop in the CO2 fixation device 15 due to CO2 fixation. This causes the CO2 concentration in the CO2 fixation device 15 to decrease, and the concentration change gradually becomes slower over time. When the slope of the CO2 concentration change exceeds a set value (e.g., -1% / hour), it is determined that CO2 fixation has been performed sufficiently. The gas in the CO2 fixation device 15 is collected in the buffer tank 19, and the waste with CO2 fixed therein is discharged from the CO2 fixation device 15. Thereafter, the gas containing CO2 in the buffer tank 19 is returned to the kneading means 16. The gas in the CO2 fixation device can be collected in the buffer tank 19 by a compressor.

[0040] In this way, by capturing and reusing the CO2 that was not fixed in the waste, it is possible to efficiently fix CO2 in the waste.

[0041] Example 3 4 shows the operation of the CO2 fixation system 130 in Example 3. In one embodiment, the CO2 fixation system 130 includes a buffer tank 19 and a pressure gauge 21, as compared with the CO2 fixation system 110 in Example 1. The buffer tank 19 communicates with the inlet and outlet of the kneading means 16. The pressure gauge 21 is disposed in the kneading means 16.

[0042] In one embodiment, CO2 fixation is carried out by steps 1-8 below.

[0043] [Table 3]

[0044] As shown in Table 3, the waste and CO2 are sealed in the CO2 fixation device 15 and kneaded. This causes the pressure inside the CO2 fixation device 15 to decrease, and the change gradually becomes slower over time. When the slope of the pressure change exceeds a set value, it is determined that CO2 fixation has been performed sufficiently. The gas inside the CO2 fixation device 15 is collected in the buffer tank 19, and the waste with the CO2 fixed therein is discharged from the kneading means 16. The gas containing CO2 inside the buffer tank 19 is then returned to the CO2 fixation device 15.

[0045] In this way, by determining that CO2 fixation has been sufficient based on the pressure change, it is possible to fix high concentrations of CO2 in the waste, making it possible to efficiently fix CO2 in the waste.

[0046] The waste in which CO2 has been fixed as described above can be transported to a final disposal site and buried. The configurations of Examples 1-3 are not limited, and each of the components can be combined. [Explanation of symbols]

[0047] 110 120 130 CO2 fixation system 9 CO2 supply device 11 Waste supply device 13 First gas supply device 15 CO2 fixation device 16 Measurement means

Claims

1. CO 2 A supply device; A waste feed device; The waste material supplied by the waste material supply device and the CO 2 CO supplied by the supply device 2 By reacting with CO 2 Generates waste with fixed CO 2 A fixing device, CO 2 The immobilization device is 2 and obtaining a rate of change of the estimated fixed amount of waste and CO until the rate of change exceeds a predetermined value. 2 CO 2 Immobilization system.

2. The CO 2 CO in the fixation device 2 and a measuring means for measuring the concentration, CO 2 The immobilization device is 2 Fixation device CO 2 The waste and CO concentration are measured until the gradient of the concentration change exceeds the set value. 2 The CO according to claim 1 is contacted with 2 Immobilization system.

3. The CO 2 3. The CO2 sensor of claim 2, further comprising a measuring means for measuring the pressure within the immobilization device. 2 Immobilization system.

4. The first gas supply device further includes a first gas supply device. 2 The CO fixation method according to claim 3, wherein the first gas is supplied in response to a pressure change in the fixation device. 2 Immobilization system.

5. The CO 2 a measuring means for measuring the pressure within the immobilization device; The CO 2 The waste and CO are mixed until the slope of the pressure change in the immobilization device exceeds the set value. 2 The CO according to claim 1 2 Immobilization system.

6. A buffer tank is further provided, and the buffer tank is configured to 2 The CO 2 The gas in the fixation device is collected and the CO 2 The CO according to claim 1 is supplied to an immobilization device. 2 Immobilization system.

7. The CO 2 7. The CO fixation method according to claim 6, wherein the gas is collected in the buffer tank until the pressure inside the fixation device reaches a set pressure. 2 Immobilization system.

8. 2. The CO2 treatment method according to claim 1, wherein the waste material includes bottom ash, soot, and non-combustible waste. 2 Immobilization system.

9. 5. The method of claim 4, wherein the first gas is ambient air or a gas that includes gases other than carbon dioxide. 2 Immobilization system.

10. The CO 2 The CO2 immobilization apparatus of claim 1 further comprises means for adding alkaline earth metal-containing material to the waste. 2 Immobilization system.

11. The CO 2 The CO2 fixation device according to claim 1 further comprises means for adding moisture. 2 Immobilization system.

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