Materializing method

Abstract

To provide a materializing method including carbonation processing that enables further improvement of a suppression effect of a carbon dioxide discharge amount.SOLUTION: Provided is a materializing method including a carbonation step of carbonizing an object to be processed by bringing the object to be processed with a carbon dioxide gas-containing fluid. Carbonation processing times T1, T2 in the carbonation step are determined on the basis of a value A of time-series information obtained by subtracting temporal change information of a carbon dioxide gas absorption amount R absorbed in the carbonation step from the temporal change information of a carbon dioxide discharge amount Pa caused by use of energy consumed in the carbonation step.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for recycling materials.

Background Art

[0002] Conventionally, in order to reuse fly ash discharged from waste incineration facilities as a material, materialization including a carbonation process has been carried out for the purpose of reducing pH and preventing elution of heavy metals. As a carbonation treatment apparatus for such materialization including a carbonation process, as disclosed in Patent Document 1, there is known one including a reaction vessel in the form of a cylindrical body with both ends closed and arranged such that the central axis of the cylindrical body is in the horizontal direction, and a stirrer having a rotating shaft arranged along the central axis of the reaction vessel.

[0003] In the carbonation treatment apparatus described in Patent Document 1, the amount of carbon dioxide gas absorbed by fly ash is measured, and when this absorption amount reaches a set value, the supply of carbon dioxide gas is terminated. Specifically, the amount of carbon dioxide gas supplied to the carbonation process and the amount of carbon dioxide gas discharged from the carbonation process are measured, and when the difference between the measured amount of carbon dioxide gas supplied and the amount of carbon dioxide gas discharged exceeds a set value of 0, the supply of carbon dioxide gas is terminated.

[0004] Further, Patent Document 2 discloses a carbonation treatment method as a waste pretreatment method. The carbonation treatment method of Patent Document 2 measures the temperature of waste in a plan view of a container body into which the waste to be carbonated is introduced, and adjusts the amount of carbon dioxide gas supplied to the container body based on the measurement result.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] By using the technologies disclosed in Patent Documents 1 and 2, it is possible to suppress the amount of carbon dioxide emissions in the carbonation treatment. In particular, in the carbonation treatment apparatus disclosed in Patent Document 1, since the amount of carbon dioxide emissions in the carbonation treatment can be suppressed to be equal to or less than the amount of carbon dioxide supplied, it is considered that a state where the amount of carbon dioxide emissions and the amount of absorption are offset or a state where the amount of carbon dioxide absorption exceeds the emissions amount has been achieved. However, even when the carbonation treatment is performed on the object to be treated such as fly ash based on the above conditions, separate power is required for stirring, aggregating, steam curing, etc. required for the intended use. Therefore, when including the amount of carbon dioxide generated when using these powers, in many cases, the amount of carbon dioxide emissions in the carbonation treatment cannot be sufficiently suppressed. That is, in the carbonation treatment by the carbonation treatment apparatus described in Patent Document 1, it is understood that carbon dioxide cannot be sufficiently reduced, and it is difficult to further improve the suppression effect of carbon dioxide emissions only by increasing the carbon dioxide absorption efficiency. Therefore, there was room for improvement in carbonating the object to be treated such as fly ash.

[0007] Therefore, there is a need for a materialization method including a carbonation treatment capable of further improving the suppression effect of carbon dioxide emissions.

Means for Solving the Problem

[0008] The materialization method according to the present invention is a materialization method including a carbonation step of bringing an object to be treated into contact with a carbon dioxide-containing fluid to carbonize the object to be treated, and based on the value of the time-series information obtained by subtracting the time-change information of the carbon dioxide absorption amount absorbed in the carbonation step from the time-change information of the carbon dioxide emission amount caused by the use of the energy consumed in the carbonation step, the carbonation treatment time in the carbonation step is determined.

[0009] According to this materialization method, it is possible to perform carbonation treatment at the carbonation treatment time determined based on the value of the time-series information obtained by subtracting the time-series change information of the carbon dioxide absorption amount from the time-series change information of the carbon dioxide emission amount due to energy use. Therefore, by setting the carbonation treatment time to the time when the value of the time-series information is the lowest and performing the carbonation treatment, the carbon dioxide emission amount can be surely suppressed. As a result, the materialization method having this feature can appropriately realize a state where the carbon dioxide emission amount and the absorption amount are offset or a state where the carbon dioxide absorption amount exceeds the emission amount.

[0010] Another feature lies in setting the carbonation treatment time in the carbonation step based on the value of the time-series information obtained by subtracting the time-series change information of the carbon dioxide absorption amount absorbed in the carbonation step from the sum of the carbon dioxide emission amount caused by the auxiliary material used in the carbonation step and the time-series change information of the carbon dioxide emission amount due to the energy consumed in the carbonation step.

[0011] According to this materialization method, it is possible to perform carbonation treatment at the carbonation treatment time determined based on the value of the time-series information obtained by subtracting the time-series change information of the carbon dioxide absorption amount from the sum of the carbon dioxide emission amount caused by the auxiliary material and the time-series change information of the carbon dioxide emission amount due to energy use. Therefore, by setting the carbonation treatment time to the time when the value of the time-series information is the lowest and performing the carbonation treatment, the carbon dioxide emission amount can be surely suppressed. As a result, the materialization method having this feature can appropriately realize a state where the carbon dioxide emission amount and the absorption amount are offset or a state where the carbon dioxide absorption amount exceeds the emission amount.

[0012] Another feature lies in determining the carbonation treatment time in the carbonation step based on the value of the time-series information obtained by adding the carbon dioxide emission amount due to the energy consumed in the granulation step including the granulation step of the object to be treated.

[0013] According to this materialization method, it is possible to perform the carbonation process at the carbonation treatment time determined based on the value of the time-series information obtained by adding the amount of carbon dioxide emissions resulting from the use of energy consumed in the granulation process. Therefore, by setting the carbonation treatment time to the time when the value of the time-series information is the lowest and performing the carbonation process, it is possible to reliably suppress the amount of carbon dioxide emissions.

[0014] Another feature is that the carbonation treatment time in the carbonation process is determined based on the value of the time-series information obtained by further adding the amount of carbon dioxide emissions resulting from the auxiliary materials used in the granulation process.

[0015] According to this materialization method, it is possible to perform the carbonation treatment at the carbonation treatment time determined based on the value of the time-series information obtained by adding the amount of carbon dioxide emissions resulting from the auxiliary materials used in the granulation process. Therefore, by setting the carbonation treatment time to the time when the value of the time-series information is the lowest and performing the carbonation process, it is possible to reliably suppress the amount of carbon dioxide emissions.

[0016] Another feature is that the carbonation treatment time is the elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes zero after changing to increasing.

[0017] As in this feature, if the carbonation treatment time is the elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes zero after changing to increasing, it is possible to reliably realize a carbonation process in which the amount of carbon dioxide emissions and absorption are offset or the amount of carbon dioxide absorption exceeds the emissions.

[0018] Another feature is that the auxiliary material contains a heavy metal elution inhibitor, the carbonation process includes a process for preventing elution of heavy metals by the heavy metal elution inhibitor, and when the second elapsed time for reducing the elution amount of the heavy metal to be equal to or less than the regulated value in the elution prevention process is longer than the first elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes zero after changing to increasing, the carbonation treatment time is set to the second elapsed time.

[0019] According to this feature, by setting the second elapsed time for restricting the elution amount of heavy metals to be equal to or less than the regulated value as the carbonation treatment time and performing the heavy metal elution prevention treatment, it is possible to surely perform the heavy metal elution prevention treatment in the carbonation step.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0021] Hereinafter, based on the drawings, the materialization method according to the embodiment of the present invention will be described in detail. Note that the embodiments described below are examples for explaining the present invention, and the present invention is not limited only to these embodiments. Therefore, the present invention can be implemented in various forms without departing from the gist thereof.

[0022] In the materialization method including the carbonation step, for example, the object to be treated containing fly ash and water is brought into contact with a gas containing carbon dioxide (an example of a carbon dioxide-containing fluid) to carbonize the fly ash. In addition, the object to be carbonized in the materialization method of the present embodiment may be any substance as long as it can be carbonized, and is not limited to fly ash. Further, the object to be carbonized in the materialization method of the present embodiment is not limited to particles.

[0023] The object to be carbonated by the materialization method of this embodiment is a solid. The solid to be carbonated may be a product generated by heat treatment. Examples of the heat treatment include simple melting or pyrolysis without thermal decomposition. The pyrolysis may be for the purpose of incineration, firing, gasification, or roasting. Examples of the object to be pyrolyzed include municipal waste, biomass, paper sludge, sewage sludge, cement raw materials, and steel raw materials. The solid to be carbonated may be a product derived from these objects to be pyrolyzed. Examples of the product generated by pyrolysis include incineration ash. Examples of the incineration ash include main ash and fly ash. The incineration ash to be carbonated may be in a molten slag state. The product generated by pyrolysis may also be slag generated in the metal refining process.

[0024] 〔First Embodiment〕 FIG. 1 shows a facility where a carbonated product is generated in the form of an incineration facility 100 having an incinerator 10 and the like. The incinerator 10 incinerates the object to be incinerated such as waste and discharges high-temperature exhaust gas.

[0025] The exhaust gas discharged from the incinerator 10 contains fly ash, which is a solid, in addition to gases such as carbon dioxide, sulfur oxides, nitrogen oxides, and hydrogen chloride. Fly ash usually contains components derived from the object to be incinerated and components derived from an alkali agent described later. The fly ash usually contains a compound containing one or more selected from the group consisting of potassium, calcium, and magnesium. The fly ash to be carbonated by the carbonation treatment device 40 and by the materialization method of this embodiment may contain a compound containing one or more selected from the group consisting of sulfur, phosphorus, and silicon. The fly ash may contain one or more selected from the group consisting of sodium, zinc, iron, aluminum, copper, and their compounds. The fly ash may also contain heavy metals such as lead and hexavalent chromium and their compounds.

[0026] Examples of the compound include oxides, hydroxides, carbides, carbonate oxides, bicarbonates, nitrides, nitrate oxides, sulfides, sulfate oxides, halides, etc. The carbonation treatment apparatus 40 in the present embodiment is used to suppress elution of heavy metals when the fly ash is carbonation-treated and then buried underground. In some examples, fly ash with a lead elution amount of 0.3 mg / L or more is carbonation-treated. In some examples, fly ash with a hexavalent chromium elution amount of 1.5 mg / L or more is carbonation-treated.

[0027] The resource utilization method can be implemented for any application and is not limited to specific equipment. For example, it can be implemented for the fly ash discharged from the incinerator 10 described later. The incineration facility 100 of the present embodiment includes an incinerator 10, a desuperheater 20, and a dust collector 30. The desuperheater 20 cools the exhaust gas discharged from the incinerator 10. The dust collector 30 includes a bag filter that removes fly ash, which is a solid component, from the exhaust gas cooled by the desuperheater 20.

[0028] Furthermore, the incineration facility 100 includes a carbonation treatment apparatus 40, a water contact apparatus 50, and a control apparatus 60. The fly ash discharged from the incinerator 10 and removed by the dust collector 30 is supplied to the carbonation treatment apparatus 40, and the carbonation treatment is performed on the fly ash in the carbonation treatment apparatus 40. The carbonation treatment apparatus 40 is configured to add water to the contained fly ash to prepare an object to be treated, and as will be described later, carbonize while stirring the object to be treated to generate a carbonized product. The water contact apparatus 50 receives part or all of the exhaust gas that has passed through the dust collector 30, brings these exhaust gases into contact with water to remove easily soluble gases in the water contact apparatus 50, and then supplies them to the carbonation treatment apparatus 40. The control apparatus 60 controls the operation of the incineration facility 100.

[0029] In this way, the incineration facility 100 is configured such that carbon dioxide (CO2, carbon dioxide gas) contained in the exhaust gas from which fly ash has been removed after passing through the dust collector 30 can be used for carbonation in the carbonation treatment device 40. More specifically, the incineration facility 100 is configured such that part or all of the exhaust gas that has passed through the dust collector 30 is brought into contact with water in the water contact device 50 to remove easily soluble gases in the water contact device and then supplied to the carbonation treatment device 40. In the water contact device 50, components that are more easily removed from the exhaust gas by contact with water than carbon dioxide, such as hydrogen chloride, sulfur dioxide, and nitrogen dioxide, can be removed. In this embodiment, the exhaust gas is supplied to the carbonation treatment device 40 as a gas containing carbon dioxide, but the gas is not limited to the exhaust gas and various gases can be used. For example, carbon dioxide gas with a purity of 99% by mass or more enclosed in a cylinder and commercially available may be supplied to the carbonation treatment device 40, or it may be carbon dioxide contained in the air.

[0030] The carbon dioxide used for carbonation treatment in the carbonation treatment device 40 may be introduced into the carbonation treatment device 40 in a liquid or solid state. For carbonation treatment, liquefied carbon dioxide or carbonated water may be used. Dry ice may be used for carbonation treatment. Also, liquids or solids (such as sodium bicarbonate and sodium carbonate) that generate carbon dioxide by thermal decomposition or chemical reaction can also be used for carbonation. Carbonation treatment can be carried out without using the water contact device 50 or the like by using high-purity carbon dioxide gas, dry ice, or the like. Carbonation treatment may also be carried out without using the water contact device 50 even when exhaust gas is used.

[0031] The carbonation treatment device 40 includes a reaction vessel 41 having an accommodation space for accommodating the object to be treated containing fly ash and water. The carbonation treatment device 40 may be a stirring device for stirring the object to be treated in the reaction vessel 41 or a curing device for curing the object to be treated in the reaction vessel 41.

[0032] In the carbonation step, after fly ash is supplied as the object to be treated to the reaction vessel 41, water, auxiliary materials described later, and exhaust gas are supplied to the reaction vessel 41 and appropriately mixed.

[0033] In the resource conversion method including the carbonation process of this embodiment, in addition to fly ash, water, and a gas containing carbon dioxide, a heavy metal immobilizing agent (an example of a heavy metal elution inhibitor) is used as a secondary material. Examples of the heavy metal immobilizing agent include calcium compounds such as calcium silicate, calcium hydroxide, calcium oxide, and calcium carbonate; phosphate compounds such as calcium phosphate and hydroxyapatite; inorganic immobilizing agents containing iron compounds such as ferrous sulfate and ferrous chloride; and organic (chelating) immobilizing agents containing dithiocarbamic acid compounds.

[0034] 〔Method for determining carbonation treatment time〕 Figure 2 is a graph showing the transition of time-dependent change information and time-series information in the carbonation process. The method for determining the carbonation treatment time will be described with reference to Figure 2. In Figure 2, the carbon dioxide emission amount derived from the secondary material is represented by P1, the change in the sum P of the carbon dioxide emission amount P1 and the carbon dioxide emission amount Pa due to power consumption over time is represented as time-dependent change information, and the change in the carbon dioxide absorption amount R due to the carbonation treatment over time is represented as time-dependent change information. In Figure 2, the change in the total sum A of the carbon dioxide amount obtained by subtracting the carbon dioxide absorption amount R from the sum P of the carbon dioxide emission amount P1 and the carbon dioxide emission amount Pa is represented as time-dependent change information. The carbonation treatment time is determined based on the total sum A, which is the value of the time-series information obtained by subtracting the time-dependent change information of the carbon dioxide absorption amount R from the sum P of the time-dependent change information of the carbon dioxide emission amount P1 and the carbon dioxide emission amount Pa.

[0035] The elapsed time T1 is the carbonation treatment time when the value of the total sum A of the carbon dioxide amount obtained by subtracting the carbon dioxide absorption amount R from the sum P of the carbon dioxide emission amount P1 and the carbon dioxide emission amount Pa is the lowest, and it is the carbonation treatment time when the value of the time-series information changes from decreasing to increasing. The elapsed time T2 represents the carbonation treatment time when the value of the time-series information changes from decreasing to increasing and the total sum A becomes 0 when the carbon dioxide absorption amount R is subtracted from the sum P of the carbon dioxide emission amount P1 and the carbon dioxide emission amount Pa. Note that at the elapsed time T3, the total sum A has turned positive, and the sum P of the carbon dioxide emission amounts is greater than the carbon dioxide absorption amount R.

[0036] Here, the amount of carbon dioxide emissions in the carbonation process refers to the amount of carbon dioxide (CO2) generated due to the use of auxiliary materials used in the carbonation process and the energy consumed in the carbonation process. Therefore, the amount of carbon dioxide emissions in the carbonation process excludes the amount of carbon dioxide emissions generated when producing the object to be carbonated (for example, the amount of carbon dioxide generated in waste incineration by the incinerator 10, etc.) and the carbon dioxide gas introduced from the outside.

[0037] 〔Amount of carbon dioxide emissions due to auxiliary materials used in the carbonation process〕 First, calculate the amount of carbon dioxide emissions P1 (see Figure 2) due to the amount of auxiliary materials used in the carbonation process. Here, the auxiliary materials used in the carbonation process are heavy metal immobilizing agents (heavy metal elution inhibitors). In this embodiment, ferrous sulfate is used as the heavy metal immobilizing agent (heavy metal elution inhibitor).

[0038] 〔Specific calculation method for the amount of carbon dioxide emissions P1 due to auxiliary materials〕 The amount of carbon dioxide emissions P1 due to the auxiliary materials used in the carbonation process can be calculated, for example, by the following formula (1). Amount of carbon dioxide emissions P1 [kg-CO2] = (emission source unit of ferrous sulfate (amount of carbon dioxide emissions per batch [kg-CO2 / ton])) × (amount of ferrous sulfate added per batch [ton]) ··· (1)

[0039] 〔Amount of carbon dioxide emissions due to the use of energy consumed in the carbonation process〕 Next, calculate the amount of carbon dioxide emissions Pa due to the use of energy consumed in the carbonation process. Here, the energy consumed in the carbonation process is the power consumption, etc. used to operate various devices such as stirrers and blowers. The power consumption is calculated based on the specifications (rated current) of various devices such as mixers and conveyors and the operating time of various devices. The power consumption may also be calculated based on the torque and frequency during operation, etc. in various devices.

[0040] 〔Specific calculation method for the amount of carbon dioxide emissions over time〕 The carbon dioxide emission amount Pa over time can be calculated, for example, by the following formula (2). Carbon dioxide emission amount Pa [kg-CO2] = (Total power per batch of various devices used in the carbonation process [kWh]) × (Carbon dioxide emission factor (for example, the CO2 emission factor of Kansai Electric Power Co., Inc. in 2020): 0.308 kg-CO2 / kWh) ··· (2) Here, the devices used in the carbonation process are, for example, mixers, cooling towers, hydraulic pumps, etc.

[0041] [Carbon dioxide absorption amount in the carbonation process] Information on the change over time of the carbon dioxide absorption amount R due to the carbonation treatment of the carbonation target in the carbonation process is calculated, for example, by the following method.

[0042] [Specific calculation method] The carbon dioxide absorption amount R is calculated, for example, from measured values such as the total carbon amount, heat loss on ignition, thermogravimetry, or the weight increase due to forced absorption of carbon dioxide. Heat loss on ignition is a method of measuring the carbon dioxide absorption amount R by incinerating the carbonation target at, for example, 600°C to reduce the weight of the carbonated product. Thermogravimetry is a method of measuring the carbon dioxide absorption amount R by changing the temperature according to a certain program and taking the mass of the sample as a function of temperature.

[0043] The control device 60 calculates, for example, the operating conditions (operating time) that minimize (carbon dioxide emission amount P1 caused by auxiliary materials) + (carbon dioxide emission amount Pa over time) - (carbon dioxide absorption amount R), and determines the carbonation treatment time based on this operating condition. These values may be calculated in advance according to the examples shown in the previous section, or may be calculated based on the data obtained by batch operation.

[0044] That is, the carbonation treatment time in the carbonation process is set based on the time-series information obtained by subtracting the time-varying information of the carbon dioxide absorption amount R absorbed in the carbonation process from the sum P of the carbon dioxide emission amount P1 caused by the amount of auxiliary materials used for the object to be treated in the carbonation process and the time-varying information of the carbon dioxide emission amount Pa caused by the use of the energy consumed in the carbonation process, for example, by the control device 60.

[0045] Specifically, the carbonation treatment time is the elapsed time T1 until the value of the time-series information changes from decreasing to increasing, or the elapsed time until it becomes 0 after the value of the time-series information related to the carbon dioxide exhaust amount changes from decreasing to increasing (the elapsed time is more than T1 and less than or equal to T2).

[0046] According to the materialization method including the carbonation process of the present embodiment, the carbonation treatment can be performed at the carbonation treatment time determined based on the time-series information obtained by subtracting the time-varying information of the carbon dioxide absorption amount R from the sum P of the carbon dioxide emission amount P1 caused by the amount of auxiliary materials and the time-varying information of the carbon dioxide emission amount Pa. Therefore, by setting the carbonation treatment time, for example, the elapsed time T1, etc., the carbon dioxide emission amount can be surely suppressed. Thereby, the materialization method including the carbonation process of the present embodiment can appropriately realize a state where the carbon dioxide emission amount and the absorption amount cancel each other out or a state where the carbon dioxide absorption amount exceeds the emission amount.

[0047] Also, if the carbonation treatment time is the elapsed time until the value of the time-series information changes from decreasing to increasing or becomes 0 after increasing (the elapsed time is more than or equal to T1 and less than or equal to T2) as in the materialization method of the present embodiment, the carbonation treatment in a state where the carbon dioxide emission amount and the absorption amount cancel each other out can be surely realized.

[0048] 〔Second Embodiment〕 In the carbonation process of the first embodiment, a heavy metal elution inhibitor is included as a secondary material used in the carbonation process, and the carbonation process includes a process for preventing the elution of heavy metals by the heavy metal elution inhibitor. In this case, in the carbonation process, the process for preventing the elution of heavy metals by the secondary material may be regarded as more important than the increase in the amount of carbon dioxide gas discharged. Therefore, in the second embodiment, when the carbonation treatment time is longer than T1 or more and T2 or less (an example of the first elapsed time), which is the elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes 0 after changing to increasing, and the elapsed time T4 (an example of the second elapsed time) for making the elution amount of heavy metals in the elution prevention process equal to or less than the regulated value, the carbonation treatment time is set to the elapsed time T4. Such setting of the carbonation treatment time is performed using, for example, the control device 60, as in the first embodiment.

[0049] According to the method of the second embodiment, by setting the second elapsed time (elapsed time T4) for making the elution amount of heavy metals equal to or less than the regulated value as the carbonation treatment time and executing the process for preventing the elution of heavy metals, it is possible to surely perform the process for preventing the elution of heavy metals in the carbonation treatment.

[0050] 〔Third Embodiment〕 As shown in FIG. 3, in the third embodiment, the incineration facility 100 further includes a granulating device 70. That is, in this embodiment, in addition to the carbonation process, a granulation process can be added to the object to be treated such as fly ash. The granulating device 70 performs a granulation process on the carbonated object to be treated conveyed from the carbonation treatment device 40. The granulating device 70 is constituted by, for example, a pelletizer. Other configurations are the same as those in the first embodiment. Specifically, the carbonated object to be treated is carried out from the bottom of the reaction vessel 41, transferred to a conveyor (not shown), and the mixture is carried into the granulating device 70 through a communication passage.

[0051] The granulation process is carried out by a mixing process and a granulation process. In the mixing process, for example, a filler and a binder are added as auxiliary materials to the carbonated object to be processed, and they are mixed while adding water. The mixing process may be carried out in the reaction vessel 41, or may be carried out in the granulator 70, or may be carried out in a mixing tank (not shown) provided in the connection passage. Then, the granulation process is carried out by the granulator 70.

[0052] Figure 4 is a graph showing the amount of carbon dioxide gas discharged in the granulation process and the transition of the change-over-time information and time-series information in the carbonation process. With reference to Figure 4, a method for determining the carbonation treatment time will be described. In Figure 4, the amount of carbon dioxide gas discharged due to the auxiliary materials used in the carbonation process is represented by P1, and the amount of carbon dioxide gas discharged Pa associated with the passage of time due to the power consumption used in the carbonation process is represented. Further, the amount of carbon dioxide gas discharged P2 obtained by adding the amount of carbon dioxide gas discharged due to the energy (for example, power consumption) consumed in the granulation process to P1 is represented, and the amount of carbon dioxide gas discharged P3 obtained by adding the amount of carbon dioxide gas discharged due to the auxiliary materials used in the granulation process to P2 is represented. The sum P of the amounts of carbon dioxide gas discharged is calculated by the sum of any one of the amounts of carbon dioxide gas discharged P1, P2, and P3 and Pa, and the change in the sum P of the amounts of carbon dioxide gas discharged is represented as change-over-time information. Further, the change in the amount of carbon dioxide gas absorption R due to the carbonation treatment with the passage of time is represented as change-over-time information. Note that the elapsed times T1 and T3 are the same as those in the first embodiment, and the elapsed time T4 is the same as that in the second embodiment.

[0053] As auxiliary materials used in the granulation process, binders, fillers, etc. are used. For these binders and fillers, they are also converted into the amount of carbon dioxide derived from raw materials. Specifically, it is the value obtained by multiplying the emission rate per unit (kg-CO2 / kg) of the binder and filler by the addition amount (kg) of the binder and filler. Therefore, in the third embodiment, after the carbonation process, a granulation process is performed in which a binder and a filler are added to the carbonated product to granulate the carbonated product. Note that the amount of carbon dioxide emissions due to the use of energy consumed in the granulation process (the amount of carbon dioxide emissions included in P2) and the amount of carbon dioxide emissions due to the auxiliary materials used in the granulation process (the amount of carbon dioxide emissions included in P3) are both fixed values, and as described above, both are added to the carbon dioxide emissions P1. For this reason, the elapsed time T2' is closer to the elapsed time T1 in the first embodiment (Figure 2). Therefore, from the viewpoint of reducing carbon dioxide emissions, the carbonation treatment time in this embodiment is preferably the elapsed time T1 until the total A, which is the value of the time-series information, changes from a decrease to an increase, or the elapsed time is more than T1 and less than or equal to T2'.

[0054] 〔Fourth Embodiment〕 In the third embodiment, an example of using auxiliary materials that are factors in generating carbon dioxide in the granulation process was shown, but the granulation process may be performed without adding auxiliary materials that are factors in generating carbon dioxide. In that case, in the graph shown in Figure 4, as indicated by the dashed-dotted line, the elapsed time until the value of the time-series information becomes 0 after turning to an increase is longer than the elapsed time T2' in the third embodiment and shorter than the elapsed time T2. Therefore, in the fourth embodiment, a carbonation treatment time longer than the elapsed time T2' in the third embodiment can be determined.

[0055] 〔Alternative Embodiment〕 (1) In the above embodiment, an example was shown in which a heavy metal elution inhibitor was added as a secondary material used in the carbonation process. However, the carbonation treatment may be performed without adding a heavy metal elution inhibitor as a secondary material. In that case, in the materialization method, based on the value of the time-series information obtained by subtracting the time-dependent change information of the carbon dioxide absorption amount absorbed in the carbonation process from the time-dependent change information of the carbon dioxide emission amount caused by the use of the energy consumed in the carbonation process, the carbonation treatment time in the carbonation process is determined.

[0056] (2) In the third embodiment, as shown in FIG. 4, an example was shown in which the carbonation process was stopped when the elapsed time was T1, or when the elapsed time was more than T1 and less than or equal to T2′, and then a secondary material used in the granulation process was added to the carbonated product and the process was shifted to the granulation process. Instead of this, the secondary material used in the granulation process may be added to the carbonated product before the carbonation treatment together with the secondary material added in the carbonation process, and then the carbonation process and the granulation process may be continuously performed. Also in this case, from the viewpoint of reducing carbon dioxide emissions, the transition from the carbonation process to the granulation process is preferably determined to be an elapsed time of T1 or more and T2′ or less as the carbonation treatment time in the materialization method.

Industrial Applicability

[0057] The present invention can be widely applied to a materialization method including carbonation treatment.

Explanation of Reference Numerals

[0058] 10: Incinerator 20: Desuperheater 30: Dust collector 40: Carbonation treatment apparatus 60: Control device 70: Granulation device 100: Incineration facility A, B: Values of time-series information (total amount of carbon dioxide gas) P: Sum of carbon dioxide emissions P1, P2: Carbon dioxide emissions Pa, Pb: Carbon dioxide emissions R: Carbon dioxide absorption amount T1: Elapsed time (First elapsed time) T2, T2´: Elapsed time (First elapsed time) T3: Elapsed time T4: Elapsed time (Second elapsed time)

Claims

1. A method for materializing a material having a carbonation step of bringing an object to be treated into contact with a carbon dioxide-containing fluid to carbonize the object to be treated, Based on the value of the time-series information obtained by subtracting the time-series change information of the amount of carbon dioxide absorbed by the object to be treated in the carbonation step from the time-series change information of the amount of carbon dioxide emissions due to the use of energy consumed in the carbonation step, a method for materializing the carbonation treatment time in the carbonation step.

2. Based on the value of the time-series information obtained by subtracting the time-series change information of the amount of carbon dioxide absorbed by the object to be treated in the carbonation treatment from the sum of the amount of carbon dioxide emissions due to the auxiliary materials used in the carbonation step and the time-series change information of the amount of carbon dioxide emissions due to the use of energy consumed in the carbonation step, the materialization method according to claim 1, wherein the carbonation treatment time in the carbonation step is determined.

3. Including a granulation step of the object to be treated, The materialization method according to claim 1 or 2, wherein the carbonation treatment time in the carbonation step is determined based on the value of the time-series information obtained by adding the amount of carbon dioxide emissions due to the use of energy consumed in the granulation step.

4. The materialization method according to claim 3, wherein the carbonation treatment time in the carbonation step is determined based on the value of the time-series information obtained by further adding the amount of carbon dioxide emissions due to the auxiliary materials used in the granulation step.

5. The materialization method according to claim 1 or 2, wherein the carbonation treatment time is the elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes zero after changing to increasing.

6. The materialization method according to claim 3, wherein the carbonation treatment time is the elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes zero after changing to increasing.

7. The materialization method according to claim 4, wherein the carbonation treatment time is the elapsed time until the value of the time-series information changes from decreasing to increasing or until it becomes zero after changing to increasing.

8. The auxiliary material contains a heavy metal elution inhibitor, The carbonation step includes a treatment for preventing elution of heavy metals with the heavy metal elution inhibitor, In the method for forming a material according to claim 2, when the second elapsed time for making the elution amount of the heavy metal not more than the regulated value in the elution prevention treatment is longer than the first elapsed time until the value of the time-series information changes from a decrease to an increase or until it becomes 0 after changing to an increase, the carbonation treatment time is set to the second elapsed time.

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