Carbonation treatment system and carbonation treatment method

Abstract

The present invention provides a carbonation treatment system and a carbonation treatment method that can obtain granules having a desired particle size in high yield. [Solution] The carbonation treatment system 10 comprises a carbonation device 1 that carbonizes a material to be treated F by bringing it into contact with carbon dioxide gas to produce a carbonated product P, a granulation device 2 that granulates the carbonated product P transported from the carbonation device 1, and a moisture content adjustment mechanism 3 that adjusts the amount of moisture added to the carbonated product P.

Description

Technical Field

[0001] The present invention relates to a carbonation treatment system and a carbonation treatment method.

Background Art

[0002] Conventionally, a carbonation treatment system has been known which reacts a treatment object such as fly ash generated by incinerating household waste or industrial waste in an incinerator with carbon dioxide gas to carbonize the treatment object and prevent elution of heavy metals and the like contained in the treatment object, and granulates the carbonated carbonation treatment product to facilitate handling of the carbonation treatment product (see, for example, Patent Document 1).

[0003] In the carbonation treatment system according to Patent Document 1, a carbonation treatment step of reacting a treatment object with carbon dioxide gas to carbonize the treatment object and a granulation step of granulating the carbonation treatment product carbonized in the carbonation treatment step to generate a granulated product are performed. In the carbonation treatment step, the water content of the treatment object in the stirring tank is calculated based on the difference between the amount of water vapor in the carbon dioxide gas and the amount of water vapor in the gas discharged from the stirring tank where the carbonation treatment is performed, and the amount of water added to the treatment object is controlled so that the calculated value falls within a set range.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When granulated carbonized material is effectively utilized as aggregate in concrete, etc., it is preferable to maintain a constant particle size. Since the particle size of the granules changes depending on the amount of water added in the carbonization process and / or the granulation process, it is important to appropriately adjust the amount of water added to the carbonized material in order to obtain granules with a desired particle size. In the carbonization system described in Patent Document 1, the amount of water added to the carbonized material is adjusted by calculating the water content of the carbonized material during the carbonization process, but this is for the purpose of effectively carrying out the carbonization process, and no adjustment of the amount of water added to the carbonized material was made in the granulation process. Therefore, the method for producing granules with a desired particle size was unknown.

[0006] Furthermore, in the carbonation treatment system described in Patent Document 1, granules are obtained by carbonizing the material to be treated in a stirring tank and then granulating the carbonated material in the same stirring tank. Therefore, the granulation process had to be performed for each carbonated material after the carbonation treatment process was completed, making it impossible to increase the amount of granules produced.

[0007] Therefore, there is a need for a carbonation treatment system and a carbonation treatment method that can produce granules with a desired particle size in high yield. [Means for solving the problem]

[0008] The characteristic configuration of the carbonation treatment system according to the present invention is that it comprises a carbonation device that generates a carbonated product by carbonizing a material to be treated by bringing it into contact with carbon dioxide gas, a granulation device that granulates the carbonated product transported from the carbonation device, and a moisture content adjustment mechanism that adjusts the amount of moisture added to the carbonated product.

[0009] This configuration includes a carbonation device that carbonizes the material to be treated to produce a carbonated product, and a granulation device that granulates the carbonated product transported from the carbonation device. This allows for continuous granulation in the granulation device, increasing the processing capacity. As a result, the yield of granulated material obtained by granulation can be increased. Furthermore, since it is equipped with a moisture content adjustment mechanism that adjusts the amount of moisture added to the carbonated product, granulated material with a desired particle size can be obtained in high yield.

[0010] Another characteristic of the moisture content adjustment mechanism is that it includes a weight measuring unit for measuring the weight of the carbonated product, a moisture content measuring unit for measuring the water content of the carbonated product, a moisture content calculation unit for calculating the amount of water to be added to the carbonated product based on the measurement results of the weight measuring unit and the water content measuring unit, and a water adding unit for adding the amount of water calculated by the moisture content calculation unit to the carbonated product.

[0011] According to this configuration, the water content calculation unit calculates the amount of water to be added to the carbonated material based on the weight of the carbonated material measured by the weight measurement unit and the water content of the carbonated material measured by the water content measurement unit. This allows the water addition unit to add the amount of water necessary for granulation of the carbonated material at the end of the carbonated treatment. As a result, for example, the amount of water contained in the carbonated material can also be taken into consideration, making it possible to appropriately adjust the amount of water necessary for granulation of the carbonated material.

[0012] Another notable feature is that the weight measuring unit and the water content measuring unit are provided in the carbonation device.

[0013] With this configuration, by providing a weight measuring unit in the carbonation device, the weight of the material to be treated supplied to the carbonation device, as well as the total weight of the material to be treated and the added water, can be measured. Furthermore, by providing a water content measuring unit in the carbonation device, for example, a contact-type moisture meter can be used.

[0014] Another characteristic feature is that the water addition section is provided in the carbonation apparatus.

[0015] With this configuration, by adding water in the carbonation device, the carbonated material and water can be uniformly mixed.

[0016] Another characteristic feature is that the material to be processed includes incinerated ash.

[0017] This configuration allows for the effective utilization of fly ash by suppressing the leaching of heavy metals contained in fly ash while carbonating Ca, K, etc., to produce a carbonated product.

[0018] The characteristic configuration of the carbonation treatment method according to the present invention is that it includes a carbonation step of carbonizing a material to be treated by bringing it into contact with carbon dioxide gas to produce a carbonated product, a granulation step of granulating the carbonated product produced in the carbonation step, a moisture content calculation step of calculating the amount of moisture to be added to the carbonated product, and a water addition step of adding the amount of water calculated in the moisture content calculation step to the carbonated product.

[0019] According to this configuration, the material to be treated is carbonated in the carbonation step, the amount of water to be added to the carbonated material is calculated in the moisture content calculation step, water is added to the carbonated material in the water addition step, and the carbonated material is granulated in the granulation step. This allows the granulation step to be carried out with an appropriate moisture content. As a result, it is possible to obtain granules with the desired particle size.

[0020] Another characteristic of the configuration is that the moisture content calculation step calculates the moisture content based on the weight and water content of the carbonated product before it is granulated in the granulation step.

[0021] According to this configuration, the moisture content is calculated based on the weight and water content of the carbonated material before granulation. For example, the moisture content contained in the carbonated material can also be taken into consideration. This makes it possible to appropriately adjust the moisture content of the carbonated material during the granulation process.

[0022] As another characteristic configuration, the water addition step is carried out on the carbonated product of the carbonation step.

[0023] According to this configuration, since water is added to the carbonated product of the carbonation step, water and the carbonated product can be uniformly mixed in the carbonation step.

[0024] As another characteristic configuration, the water addition step is carried out on the carbonated product of the granulation step.

[0025] According to this configuration, since water is added to the carbonated product after the carbonation step, an appropriate amount of water required for granulating the carbonated product can be added.

[0026] As another characteristic configuration, the object to be processed contains incineration ash.

[0027] According to this configuration, since heavy metals contained in fly ash can be suppressed from eluting while Ca, K, etc. are carbonated to produce a carbonated product, fly ash can be effectively utilized.

Brief Description of the Drawings

[0028] [Figure 1] It is a configuration diagram of a carbonation treatment system according to the first embodiment. [Figure 2] It is a flowchart showing a carbonation treatment method. [Figure 3] It is a configuration diagram of a carbonation treatment system according to the second embodiment. [Figure 4] It is a configuration diagram of a carbonation treatment system according to the third embodiment. [Figure 5] It is a configuration diagram of a carbonation treatment system according to the fourth embodiment. [Figure 6] It is a configuration diagram of a carbonation treatment system according to the fifth embodiment. [Figure 7] It is a configuration diagram of a carbonation treatment system according to the sixth embodiment. <了 [Modes for carrying out the invention]

[0029] Embodiments of the carbonation treatment system and carbonation treatment method according to the present invention will be described below with reference to the drawings. However, the invention is not limited to the embodiments described below, and various modifications are possible without departing from the spirit of the invention.

[0030] [First Embodiment] The carbonation treatment system 10 and carbonation treatment method according to the first embodiment will be described with reference to Figures 1 and 2. As shown in Figure 1, the carbonation treatment system 10 comprises a carbonation device 1 that carbonizes a material to be treated F to produce a carbonated product P, a granulation device 2 that granulates the carbonated product P, and a moisture content adjustment mechanism 3 that adjusts the amount of moisture added to the carbonated product P.

[0031] The material to be treated F is, for example, bottom ash or fly ash generated when general waste or industrial waste is incinerated in an incinerator, or incinerated ash from wood biomass power generation. The material to be treated F may also be slag generated in the steel manufacturing process, or recycled aggregate, sludge, or dust generated in the concrete recycling process. The material to be treated F may also be a mixture of these. Such material to be treated F contains calcium derived from slaked lime, and heavy metals such as lead and cadmium.

[0032] The carbonation device 1 is a known mixer, such as a twin-screw mixer, vortex mixer, or paddle mixer, which has stirring blades. The material F to be processed supplied to the carbonation device 1 is mixed and stirred to ensure uniform mixing.

[0033] The carbonation device 1 has a water addition unit 34 for adding water to its interior and a carbon dioxide supply unit (not shown) for supplying carbon dioxide. The carbon dioxide may be air or exhaust gas containing carbon dioxide. By supplying water and carbon dioxide to the material to be treated F, the carbon dioxide reacts with the Ca, K, etc. contained in the material to be treated F to produce a carbonated product P. Some of the heavy metals contained in the material to be treated F are immobilized in the carbonated product P by carbonation. In addition, a heavy metal immobilizer may be supplied to the material to be treated F from a heavy metal immobilizer supply unit (not shown) provided in the carbonation device 1.

[0034] Furthermore, the carbonation apparatus 1 may have a cement addition section (not shown) for adding fillers and cement in order to granulate the carbonated material P in the granulation apparatus 2 described later. By adding fillers and cement to the carbonated material P that has undergone carbonation treatment, the granulation of the carbonated material P can be carried out efficiently.

[0035] The carbonated material P produced in the carbonation device 1 is transported to the granulation device 2 by a transport device (not shown). The transport device is, for example, a conveyor. As the carbonated material P is discharged from the carbonation device 1 and transported, continuous granulation can be performed in the granulation device 2.

[0036] The granulation apparatus 2 is a granulator such as a rotary pan type, rotary drum type, rotary cone type, rotary horizontal disc type, or agitation granulation type, which granulates the carbonated material P to produce granulated material G. The size of the granulated material G varies depending on the granulation time in the granulation apparatus 2 and the water content of the carbonated material P. Therefore, in order to obtain granulated material G of a desired particle size, it is necessary to control the water content of the carbonated material P supplied to the granulation apparatus 2. Accordingly, the carbonation treatment system 10 in this embodiment is equipped with a water content adjustment mechanism 3 that adjusts the amount of water added to the carbonated material P to control the water content of the carbonated material P in the granulation apparatus 2.

[0037] The moisture content adjustment mechanism 3 includes a weight measuring unit 31 for measuring the weight of the carbonated product P, a moisture content measuring unit 32 for measuring the water content of the carbonated product P, a moisture content calculation unit 33 for calculating the amount of water to be added to the carbonated product P based on the measurement results of the weight measuring unit 31 and the moisture content measuring unit 32, and a water adding unit 34 for adding the amount of water calculated by the moisture content calculation unit 33 to the carbonated product P.

[0038] The weight measuring unit 31 is provided in the carbonation device 1 and measures the weight of the material to be processed F and water supplied to the carbonation device 1. The water content measuring unit 32 is also provided in the carbonation device 1, similar to the weight measuring unit 31. The water content measuring unit 32 may be a measuring instrument that performs contact measurement equipped with a sensor probe, or it may be a measuring instrument that performs non-contact measurement, such as an infrared moisture meter. The water content measuring unit 32 can measure the water content of the carbonation processed material P. The measured values ​​measured by the weight measuring unit 31 and the water content measuring unit 32 may be stored in a memory unit provided in the carbonation processing system 10.

[0039] The moisture content calculation unit 33 is operated by a control unit (not shown) that controls the carbonation treatment system 10. The control unit has a processor and includes other hardware for executing applications stored in a memory unit (not shown) of the carbonation treatment system 10. The moisture content calculation unit 33 obtains measurement results measured by the weight measurement unit 31 and the moisture content measurement unit 32 from the memory unit. Alternatively, the moisture content calculation unit 33 may directly obtain measurement results from the weight measurement unit 31 and the moisture content measurement unit 32. The moisture content calculation unit 33 calculates the amount of moisture required for granulation of the carbonation treatment material P from the moisture content of the carbonation treatment material P measured by the moisture content measurement unit 32 and the weight of the material to be treated F, filler, cement, etc. supplied to the carbonation device 1. The moisture content may be calculated using a calculation formula stored in the moisture content calculation unit 33, or by referring to a calculation formula stored in a memory unit (not shown). The water addition unit 34 adds water based on the amount of water calculated by the water content calculation unit 33.

[0040] In the carbonation apparatus 1, carbonation is performed by supplying water and carbon dioxide to the material to be treated F. Some of the water added during the carbonation process may remain in the carbonation apparatus 1 without reacting with the material to be treated F. Therefore, if the amount of water required for granulation is calculated based on the weight of the mixture in the carbonation apparatus 1 after carbonation, without considering the water content in the carbonated material P, there is a risk of exceeding the appropriate water content. Therefore, as in this embodiment, by measuring the water content of the carbonated material P after carbonation, and calculating and adding the amount of water required for granulation of the carbonated material P based on the water content and the weight of the material to be treated F, filler, cement, etc., it is possible to obtain granulated material G with the desired particle size even if the carbonated material P contains water.

[0041] Furthermore, since the filler and cement may contain water, the moisture content adjustment mechanism 3 may, after the material to be treated F has been carbonated and the filler and cement have been added to the carbonation device 1, measure the amount of water contained in the carbonated treated material P, filler and cement in the carbonation device 1, and calculate and add the amount of water necessary for granulation of the carbonated treated material P based on these amounts and weights.

[0042] Next, the carbonation treatment method using the carbonation treatment system 10 will be explained with reference to Figure 2. The carbonation treatment method includes a carbonation treatment step (S1), a moisture content calculation step (S2), a water addition step (S3), and a granulation step (S4).

[0043] In the carbonation process (S1), first, the material to be treated F is supplied to the carbonation apparatus 1. The carbonation apparatus 1 homogenizes the material to be treated F by stirring and mixing it. It is preferable that the stirring in the carbonation apparatus 1 is performed continuously. Next, water for the carbonation treatment is added to the carbonation apparatus 1 by the water addition unit 34. The amount of water for the carbonation treatment may be determined based on the weight of the material to be treated measured by the weight measuring unit 31. The material to be treated F supplied to the carbonation apparatus 1 and the water are mixed uniformly. A heavy metal immobilizing agent may be added before or after the addition of water.

[0044] Next, carbon dioxide is supplied to the carbonation device 1, and the supplied carbon dioxide reacts with the components contained in the material F to be treated to produce the carbonated product P. Since the reaction that produces the carbonated product P is an exothermic reaction, the amount of water added to the carbonation device 1 for the carbonation treatment may decrease from the amount added at the time of addition.

[0045] After the carbonation process (S1) is completed, filler and cement are added to the carbonation device 1. The amount of filler and cement added may be determined by the weight of the material to be treated F. The filler and cement are uniformly mixed with the carbonized material P by the carbonation device 1.

[0046] Next, the moisture content calculation process (S2) is performed. In the moisture content calculation process (S2), first, the moisture content measuring unit 32 measures the moisture content of the carbonated product P after the carbonation treatment is completed. The moisture content of the carbonated product P may be measured before the addition of fillers and cement, or after their addition. If the measurement is performed after the addition of fillers and cement, their moisture content may also be taken into consideration. The moisture content of the carbonated product P measured by the moisture content measuring unit 32 is obtained by the moisture content calculation unit 33. The moisture content calculation unit 33 also obtains the weight of the treated material F measured by the weight measuring unit 31, as well as the weights of the heavy metal immobilizer, fillers, and cement. The moisture content calculation unit 33 then calculates the amount of water to be added to the carbonated material P in order to create granules G having the desired particle size, based on the water content of the carbonated material P, the weight of the material to be treated F, the weight of the heavy metal immobilizer, the filler, and the cement.

[0047] In the water addition step (S3), the water addition unit 34 adds the amount of water calculated by the water content calculation unit 33 to the carbonated product P. The added water and the carbonated product P are then uniformly mixed by the carbonation device 1.

[0048] After the water addition step (S3), the carbonated material P, mixed with water, is discharged from the carbonation device 1 and transported to the granulation device 2 by a conveying device such as a conveyor. In the granulation device 2, the granulation step (S4) is performed and the carbonated material P is granulated. In this embodiment, since the water content of the carbonated material P introduced into the granulation device 2 is appropriately adjusted, the granulation device 2 produces granules G having the desired particle size.

[0049] The granulated material G obtained in this way can be effectively utilized, for example, as aggregate in concrete.

[0050] [Second Embodiment] A carbonation treatment system 10 according to the second embodiment will be described with reference to Figure 3. In this embodiment, as shown in Figure 3, a water content measuring unit 32 is provided between the carbonation device 1 and the granulation device 2. The other configurations are the same as in the first embodiment, so a detailed explanation will be omitted.

[0051] The water content measuring unit 32 may be provided, for example, on a conveying device that transports the carbonated material P discharged from the carbonation device 1 to the granulation device 2. This makes it possible to measure the water content of the carbonated material P immediately before granulation. Therefore, it is also possible to take into account the water that evaporates before it is fed into the granulation device 2.

[0052] [Third Embodiment] A carbonation treatment system 10 according to the third embodiment will be described with reference to Figure 4. In this embodiment, as shown in Figure 4, a water addition unit 34 is provided between the carbonation device 1 and the granulation device 2. The other configurations are the same as in the first embodiment, so a detailed explanation will be omitted.

[0053] The water addition unit 34 may be provided, for example, on a conveying device that transports the carbonated material P discharged from the carbonation device 1 to the granulation device 2. In this embodiment, the water addition unit 34 has a nozzle or the like and sprays water onto the carbonated material P. This allows the surface of the carbonated material P to be wetted with water, enabling sufficient granulation.

[0054] [Fourth Embodiment] A carbonation treatment system 10 according to the fourth embodiment will be described with reference to Figure 5. In this embodiment, as shown in Figure 5, a water content measuring unit 32 and a water addition unit 34 are provided between the carbonation device 1 and the granulation device 2. The other configurations are the same as in the first embodiment, so a detailed explanation will be omitted.

[0055] The water content measuring unit 32 and the water addition unit 34 may be provided, for example, on a conveying device that transports the carbonated material P discharged from the carbonation device 1 to the granulation device 2. This makes it possible to measure the water content of the carbonated material P immediately before granulation. Furthermore, since water can be added to the carbonated material P immediately before granulation, water does not evaporate during the transport of the carbonated material P, and the water content of the carbonated material P in the granulation process can be brought closer to an appropriate value.

[0056] [Fifth Embodiment] The carbonation treatment system 10 according to the fifth embodiment will be described with reference to Figure 6. In this embodiment, as shown in Figure 6, a water addition unit 34 is provided in the granulation apparatus 2. The other configurations are the same as in the first embodiment, so a detailed explanation will be omitted.

[0057] By providing the water addition unit 34 in the granulation apparatus 2, water does not evaporate during the transport of the carbonated material P, and the water content of the carbonated material P in the granulation process can be brought closer to an appropriate value.

[0058] [Sixth Embodiment] A carbonation treatment system 10 according to the sixth embodiment will be described with reference to Figure 7. In this embodiment, as shown in Figure 7, a water content measuring unit 32 is provided between the carbonation device 1 and the granulation device 2, and a water addition unit 34 is provided in the granulation device 2. The other configurations are the same as in the first embodiment, so a detailed explanation will be omitted.

[0059] The water content measuring unit 32 may be provided, for example, on a conveying device that transports the carbonated material P discharged from the carbonation device 1 to the granulation device 2. This makes it possible to measure the water content of the carbonated material P immediately before granulation. Furthermore, by providing the water addition unit 34 in the granulation device 2, water does not evaporate during the transport of the carbonated material P, and the water content of the carbonated material P in the granulation process can be brought closer to an appropriate value.

[0060] [Other Embodiments] (a) In the above embodiment, the weight measuring unit 31 is provided in the carbonation device 1, but the weight measuring unit 31 may also be provided in a conveying device located between the carbonation device 1 and the granulation device 2. In this case, the moisture content calculation unit 33 may calculate the weight of substances other than water in the mixture from the moisture content of the mixture of the carbonized product P and cement, etc., and the weight of the mixture of the carbonized product P and cement, etc., discharged from the carbonation device 1, and then calculate the amount of moisture to be added to the carbonized product P.

[0061] (b) In the above embodiment, the water content measuring unit 32 is provided in the carbonation device 1, but if the carbonation device 1 can measure the water content of the carbonation treatment product P, etc., the water content measuring unit 32 may be independent of the carbonation device 1 or may not be provided in the carbonation device 1.

[0062] (c) In the above embodiment, the water content measuring unit 32 is provided on the carbonation device 1 or on the conveying device that transports the carbonation treated material P from the carbonation device 1 to the granulation device 2, but it may be provided on either of these. Also, the water content of fillers, cement, etc. to be put into the carbonation device 1 may be measured before being put into the carbonation device 1. The water content calculation unit 33 may calculate the amount of water to be added to the carbonation device 1 using the water content of fillers, cement, etc. measured before input. [Industrial applicability]

[0063] The present invention can be used in a carbonation treatment system and a carbonation treatment method that generate a carbonated product by carbonizing a material to be treated by bringing it into contact with carbon dioxide gas. [Explanation of Symbols]

[0064] 1: Carbonation device 2: Granulation device 3: Moisture adjustment mechanism 10: Carbonation treatment system 31: Weight measurement unit 32: Moisture content measurement unit 33: Moisture Content Calculation Department 34: Water addition section F: Workpiece P: Carbonated product

Claims

1. A carbonation apparatus that generates a carbonated product by carbonizing a material to be treated by bringing it into contact with carbon dioxide gas, A granulation apparatus for granulating the carbonated material transported from the carbonation apparatus, A carbonation treatment system comprising a moisture content adjustment mechanism for adjusting the amount of moisture added to the carbonation treatment product.

2. The carbonation treatment system according to claim 1, wherein the moisture content adjustment mechanism comprises a weight measuring unit for measuring the weight of the carbonation treatment product, a moisture content measuring unit for measuring the moisture content of the carbonation treatment product, a moisture content calculation unit for calculating the amount of moisture to be added to the carbonation treatment product based on the measurement results of the weight measuring unit and the moisture content measuring unit, and a water adding unit for adding the amount of water calculated by the moisture content calculation unit to the carbonation treatment product.

3. The carbonation treatment system according to claim 2, wherein the weight measuring unit and the water content measuring unit are provided in the carbonation device.

4. The carbonation treatment system according to claim 2 or 3, wherein the water addition unit is provided in the carbonation device.

5. The carbonation treatment system according to any one of claims 1 to 3, wherein the material to be treated includes incinerated ash.

6. A carbonation process involves bringing the material to be treated into contact with carbon dioxide to carbonate it and produce a carbonated product, A granulation step for granulating the carbonated product produced in the carbonation step, A water content calculation step for determining the amount of water to be added to the carbonation treatment product, A carbonation treatment method comprising a water addition step of adding the amount of water calculated in the water content calculation step to the carbonation treatment product.

7. The carbonation treatment method according to claim 6, wherein the moisture content calculation step calculates the moisture content based on the weight and water content of the carbonation treatment product before it is granulated in the granulation step.

8. The carbonation method according to claim 7, wherein the water addition step is performed on the carbonized product of the carbonation step.

9. The carbonation treatment method according to claim 7, wherein the water addition step is performed on the carbonized product of the granulation step.

10. The carbonation treatment method according to any one of claims 6 to 9, wherein the material to be treated includes incinerated ash.

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