Method for estimating carbon adhesion amount

Abstract

To provide a method for estimating a carbon adhesion amount, capable of rapidly and easily estimating an amount of carbon adhered to an inner wall of a carbonization chamber for unknown coal.SOLUTION: A method for estimating a carbon adhesion amount includes: a step 1 of obtaining a gas generation amount generated during temperature increase from 150°C to 400°C for a plurality of coals for correlation equation creation; a step 2 of obtaining a carbon adhesion amount for the plurality of coals for correlation equation creation by using a predetermined method for collecting furnace wall carbon; a step 3 of obtaining a correlation equation between a gas generation amount and a carbon adhesion amount from the gas generation amount obtained in the step 1 and the carbon adhesion amount obtained in the step 2; a step 4 of obtaining a gas generation amount of coal to be evaluated; and a step 5 of obtaining an estimated carbon adhesion amount of the coal to be evaluated, based on the gas generation amount of the coal to be evaluated obtained in the step 4 and the correlation equation obtained in the step 3.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a method for estimating carbon deposition amount. [Background technology]

[0002] When coal is charged into a coke oven chamber and carbonized, the gas generated from the coal precipitates as carbon, which adheres to the chamber walls. With repeated carbonization, this carbon grows, but if the amount of carbon adhering to the chamber walls becomes excessive, the resistance to coke extrusion, as exemplified by the extrusion power, increases, causing clogging and damaging the chamber walls.

[0003] Patent Document 1 discloses a method of operating a coke oven for smoothly pushing coke from the coke oven carbonization chamber, which is characterized by determining the amount of wall-side coke contraction, carbon adhesion thickness, and oven wall displacement during pushing, setting the oven wall coke spacing to a value obtained by subtracting the carbon adhesion thickness and oven wall displacement from the wall-side coke contraction amount during pushing, determining a minimum oven wall coke spacing value in advance, and selecting coke oven operating conditions so that the oven wall coke spacing is greater than the minimum oven wall coke spacing value (Claim 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-290658 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the evaluation of the amount of carbon deposition using various factors as in Patent Document 1, estimation is performed using many influencing factors, so the evaluation procedure is complicated and the measurement and analysis take a very long time. Therefore, it is not suitable for evaluating unknown coals, and it is difficult to say that it is possible to appropriately evaluate the carbon deposited on the inner wall of a coke chamber quickly and easily.

[0006] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a method for estimating the amount of carbon adhesion, which makes it possible to quickly and simply estimate the amount of carbon adhering to the inner wall of a coke chamber for unknown coal. [Means for solving the problem]

[0007] The present inventors have conducted extensive research into a method for estimating the amount of carbon deposited on an unknown coal (coal to be evaluated). As a result, they have found that by employing the following configuration, it is possible to quickly and easily estimate the amount of carbon deposited on the inner wall of a coke chamber, and have thus completed the present invention.

[0008] That is, the present invention provides the following. [1] Step 1: determining the amount of gas generated when a temperature of multiple coals used to create a correlation equation is increased from 150°C to 400°C; Step 2: determining the carbon deposition amount of the plurality of coals for creating the correlation equation using the furnace wall carbon collection method described below; a step 3 of obtaining a correlation equation between the amount of gas generated and the amount of carbon deposited from the amount of gas generated obtained in the step 1 and the amount of carbon deposited in the step 2; Step 4: determining the gas generation rate of the coal to be evaluated; a step 5 of determining an estimated carbon deposition amount of the coal to be evaluated from the gas generation amount of the coal to be evaluated determined in the step 4 and the correlation equation obtained in the step 3; A method for estimating carbon deposition amount, comprising: <Method for collecting furnace wall carbon> Providing a furnace wall carbon collection container, The furnace wall carbon collection container is It is made up of bricks, a sealed container including a circular plate-shaped bottom, a hollow cylindrical coal burning unit disposed on the bottom, a hollow cylindrical furnace wall carbon deposition unit disposed on the coal burning unit and having the same inner and outer diameters as the coal burning unit, and a circular plate-shaped lid disposed on the furnace wall carbon deposition unit; a cylindrical spacer portion enclosed in the sealed container; Equipped with The outer diameters of the coal burning section and the furnace wall carbon deposition section are 20 mm or more and 52 mm or less, The wall thickness of the coal burning section and the furnace wall carbon deposition section is 1 mm or more and 5 mm or less, The height of the coal burning section is 30 mm or more and 50 mm or less, The height of the carbon deposit portion on the furnace wall is 30 mm or more and 50 mm or less, The gap between the outer wall of the spacer portion and the inner walls of the coal burning portion and the furnace wall carbon deposition portion is 1 mm or more and 5 mm or less, a step X in which the height of the spacer portion is 35 mm or more and 55 mm or less; A step A of placing coal between the bottom of the furnace wall carbon collecting container and the spacer portion; After the step A, a step B is performed in which the furnace wall carbon collection container having the coal disposed therein is charged into a heater adjusted to a temperature range of 700°C or higher and 1200°C or lower; After the step B, a step C is performed in which the furnace wall carbon collecting container is removed from the heater and the furnace wall carbon adhered to the furnace wall carbon adhering portion is obtained. A method for collecting furnace wall carbon comprising:

[0009] It has been known that there is a relationship between VM (volatile matter) and carbon deposition amount, but there are some coal types that deviate from this trend. Furthermore, it has been believed that the formation of furnace wall carbon is influenced by tar and pyrolysis gases that are generated during softening and melting (at temperatures above 400°C) (see, for example, Kunihiko Nishioka, Fossils of the Sun: Coal, Gune Technology Center, October 1990). However, as a result of investigations by the inventors, it was confirmed that white smoke and tarry components were generated not only in the softening and melting range (above 400°C) but also up to 400°C, indicating that low-temperature components are also involved in carbon formation. Specifically, MS spectra obtained when heated below 400°C confirmed that pyrolysis components with large molecular weights that are thought to affect carbon formation were also generated at low temperatures (below 400°C). As a result of extensive research, the present inventors have confirmed that there is a correlation between the amount of gas generated and the amount of carbon deposition in the temperature range of 150 to 400°C.

[0010] According to the above configuration, a correlation equation between the gas generation rate and carbon deposition rate is obtained from the gas generation rate that occurs when a plurality of coals used to create a correlation equation are heated from 150°C to 400°C and the carbon deposition rate that is determined using the furnace wall carbon collection method.Then, an estimated carbon deposition rate of the coal to be evaluated is determined from the gas generation rate of the coal to be evaluated and the obtained correlation equation. According to the above configuration, a correlation equation is obtained from the evolved gas and the amount of carbon, rather than using various factors, which is simple. Furthermore, by measuring the amount of evolved gas in the range of 150 to 400°C, the estimated amount of carbon deposition on the coal being evaluated can be obtained, allowing results to be obtained quickly.

[0011] The carbon collection method described above is a carbon collection method that the applicant has already applied for (Patent Application No. 2023-125377).

[0012] Typically, the walls of a coke oven are made of bricks. According to the above configuration, the oven wall carbon collection container is made of bricks, so that an environment more similar to that of an actual oven (coke oven) can be created.

[0013] Furthermore, according to the above configuration, the furnace wall carbon collection container has a relatively small overall size, as described above. Therefore, coal can be carbonized in a short time. As a result, furnace wall carbon can be collected in a short time.

[0014] Furthermore, with this configuration, the thickness of the coal burning section and the furnace wall carbon deposition section is between 1 mm and 5 mm, which is relatively thin, and therefore the temperature outside is easily transferred to the inside during carbonization, making it possible to carbonize the coal in a short time.

[0015] Furthermore, with the above configuration, since the height of the coal burning section is 30 mm or more and 50 mm or less, a relatively large amount of coal can be placed in the coal burning section. As a result, it is possible to collect a large amount of furnace wall carbon. Furthermore, since the height of the coal burning section is 30 mm or more and 50 mm or less, coke powder adheres to the coal burning section, and it is possible to prevent coke powder from adhering to the carbon-adhering section of the furnace wall.

[0016] Furthermore, according to the above configuration, the height of the carbon deposition portion on the furnace wall is 30 mm or more and 50 mm or less, and the carbon on the furnace wall adheres to this portion. As a result, it is possible to collect a large amount of carbon on the furnace wall.

[0017] Regarding furnace wall carbon, the inventors have discovered that primary pyrolysis gas generated when coal softens and melts (around 350 to 500°C) comes into contact with the high-temperature furnace wall and is heated, causing secondary pyrolysis, which results in carbon adhering to the furnace wall. As a result, they have found that the most efficient way to collect a large amount of furnace wall carbon is to bring the primary pyrolysis gas into contact with a high-temperature object at the same time as it is generated. Therefore, the gap between the outer wall of the spacer and the inner walls of the coal burning section and the carbon deposition section on the furnace wall is set to 1 mm or more and 5 mm or less. As a result, the primary pyrolysis gas of coal can be brought into contact with the high-temperature coal burning section and the carbon deposition section on the furnace wall simultaneously with its generation, making it possible to efficiently collect carbon on the furnace wall.

[0018] Furthermore, according to the above configuration, since the spacer portion is provided, it is possible to prevent coal and coke from flying up. Furthermore, since the height of the spacer portion is 35 mm or more, the gap between the inner wall of the coal burning portion and the carbon deposition portion on the furnace wall can be set to 1 mm or more and 5 mm or less, allowing the primary pyrolysis gas to come into contact with the high-temperature coal burning portion and the carbon deposition portion on the furnace wall, making it possible to efficiently collect carbon on the furnace wall.

[0019] As described above, the furnace wall carbon collection container having the above-described configuration makes it possible to collect a larger amount of furnace wall carbon in a shorter time.

[0020] Furthermore, the present invention provides the following: [2] The method for estimating the amount of carbon deposition according to [1], wherein the amount of gas generated is a value determined by thermogravimetry when the temperature of coal is raised from 150°C to 400°C.

[0021] If the amount of gas generated is a value determined by thermogravimetry when the temperature of coal is raised from 150°C to 400°C, the amount of carbon adhesion can be estimated with higher accuracy.

[0022] Furthermore, the present invention provides the following: [3] The method for estimating the carbon deposition amount according to [1], wherein the amount of gas generated is a value determined from the area of ​​a total ion chromatogram (TIC) obtained by mass spectrometry of gas generated when coal is heated from 150°C to 400°C.

[0023] If the amount of gas generated is a value calculated from the area of ​​a total ion chromatogram (TIC) obtained by mass spectrometry of gas generated when coal is heated from 150°C to 400°C, the amount of carbon adhesion can be estimated more accurately. [Effects of the Invention]

[0024] According to the present invention, it is possible to provide a method for estimating the amount of carbon adhesion, which makes it possible to quickly and simply estimate the amount of carbon that adheres to the inner wall of a coke chamber for unknown coal. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 2 is a schematic diagram for explaining a furnace wall carbon collection container according to the present embodiment. [Figure 2] FIG. 2 is a schematic diagram for explaining a method for collecting furnace wall carbon according to the present embodiment. [Figure 3] 1 is a graph showing the relationship between the thermal weight loss rate (TG) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by linear fitting using the least squares method. [Figure 4] 1 is a graph showing the relationship between the total ion chromatogram (TIC) and the amount of carbon deposition when the temperature is increased from 150° C. to 400° C., and is a graph obtained by linear fitting using the least squares method. [Figure 5] 1 is a graph showing the relationship between the thermal weight loss rate (TG) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by linear fitting using the least squares method. [Figure 6] 1 is a graph showing the relationship between the total ion chromatogram (TIC) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by performing linear fitting by the least squares method. [Figure 7] 1 is a graph showing the relationship between the thermal weight loss rate (TG) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by performing quadratic fitting using the least squares method. [Figure 8] 1 is a graph showing the relationship between the total ion chromatogram (TIC) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by performing quadratic fitting by the least squares method. [Figure 9] 1 is a graph showing the relationship between VM and carbon deposition amount. DETAILED DESCRIPTION OF THE INVENTION

[0026] The method for estimating the amount of carbon adhesion according to this embodiment will be described below.

[0027] The method for estimating the carbon adhesion amount according to this embodiment is as follows: Step 1: determining the amount of gas generated when a temperature of multiple coals used to create a correlation equation is increased from 150°C to 400°C; Step 2: determining the carbon deposition amount of the plurality of coals for creating the correlation equation using the furnace wall carbon collection method described below; a step 3 of obtaining a correlation equation between the amount of gas generated and the amount of carbon deposited from the amount of gas generated obtained in the step 1 and the amount of carbon deposited in the step 2; Step 4: determining the gas generation rate of the coal to be evaluated; a step 5 of determining an estimated carbon deposition amount of the coal to be evaluated from the gas generation amount of the coal to be evaluated determined in the step 4 and the correlation equation obtained in the step 3; It has. <Method for collecting furnace wall carbon> Providing a furnace wall carbon collection container, The furnace wall carbon collection container is It is made up of bricks, a sealed container including a circular plate-shaped bottom, a hollow cylindrical coal burning unit disposed on the bottom, a hollow cylindrical furnace wall carbon deposition unit disposed on the coal burning unit and having the same inner and outer diameters as the coal burning unit, and a circular plate-shaped lid disposed on the furnace wall carbon deposition unit; a cylindrical spacer portion enclosed in the sealed container; Equipped with The outer diameters of the coal burning section and the furnace wall carbon deposition section are 20 mm or more and 52 mm or less, The wall thickness of the coal burning section and the furnace wall carbon deposition section is 1 mm or more and 5 mm or less, The height of the coal burning section is 30 mm or more and 50 mm or less, The height of the carbon deposit portion on the furnace wall is 30 mm or more and 50 mm or less, The gap between the outer wall of the spacer portion and the inner walls of the coal burning portion and the furnace wall carbon deposition portion is 1 mm or more and 5 mm or less, a step X in which the height of the spacer portion is 35 mm or more and 55 mm or less; A step A of placing coal between the bottom of the furnace wall carbon collecting container and the spacer portion; After the step A, a step B is performed in which the furnace wall carbon collection container having the coal disposed therein is charged into a heater adjusted to a temperature range of 700°C or higher and 1200°C or lower; After the step B, a step C is performed in which the furnace wall carbon collecting container is removed from the heater and the furnace wall carbon adhered to the furnace wall carbon adhering portion is obtained. A method for collecting furnace wall carbon comprising:

[0028] (Process 1) In the method for collecting furnace wall carbon according to this embodiment, first, the amount of gas generated when the temperature of a plurality of coals used to create a correlation equation is increased from 150°C to 400°C is determined.

[0029] The amount of gas generated is preferably a value determined by thermogravimetry when the temperature of coal is raised from 150°C to 400°C.

[0030] If the gas generation rate is a value determined by thermogravimetry when the temperature of coal is raised from 150°C to 400°C, the carbon deposition amount can be estimated with higher accuracy. This is also clear from the results of the Examples.

[0031] The amount of gas generated may be a value determined from the area of ​​a total ion chromatogram (TIC) obtained by mass spectrometry of gas generated when coal is heated from 150°C to 400°C.

[0032] Even if the amount of gas generated is a value calculated from the area of ​​the total ion chromatogram (TIC) obtained by mass spectrometry of the gas generated when coal is heated from 150°C to 400°C, the amount of carbon deposition can be estimated with higher accuracy. This is also clear from the results of the Examples.

[0033] The amount of gas generated can be measured by any device, as long as it can be measured by thermogravimetry and / or mass spectrometry. For example, TG-GC, TG-GCMS, TG-DTA, etc. can be used.

[0034] From the viewpoint of obtaining a more accurate correlation equation, the number (types) of coals used to create the correlation equation is preferably 15 or more, and more preferably 20 or more. From the viewpoint of efficiency, the number (types) of multiple coals used to create the correlation equation may be 30 or less.

[0035] From the viewpoint of obtaining a more accurate correlation equation, it is preferable to use coals with various gas generation rates as the coals used to create the correlation equation.

[0036] When the rate of thermal gravitational loss (TG) during heating from 150°C to 400°C is used as the gas generation rate, the coal used to create the correlation equation preferably includes one or more samples with a TG of 2.0% or less. It also preferably includes five or more samples with a TG of more than 2.0% and less than or equal to 4.0%. It also preferably includes one or more samples with a TG of more than 4.0%.

[0037] When the area of ​​the total ion chromatogram (TIC) during the temperature rise from 150°C to 400°C is used as the amount of gas generated, the coal used to create the correlation equation preferably includes one or more samples with a TIC area of ​​5.0E+06 or less. It also preferably includes five or more samples with a TIC area of ​​more than 5.0E+06 and less than or equal to 5.5E+06. It also preferably includes one or more samples with a TIC area of ​​more than 5.5E+06.

[0038] (Process 2) In addition, in the method for collecting furnace wall carbon according to this embodiment, the carbon deposition amount of the plurality of coals used to create the correlation equation is determined using the furnace wall carbon collection method described below.

[0039] First, the furnace wall carbon collecting container 10 according to this embodiment will be described below. Fig. 1 is a schematic diagram illustrating a furnace wall carbon collection container according to this embodiment. The furnace wall carbon collection container 10 is a container for collecting furnace wall carbon generated when coal is coked. Specifically, the furnace wall carbon collection container 10 can be suitably used in a furnace wall carbon collection method described below.

[0040] The furnace wall carbon collection container 10 is made of bricks. Because the furnace wall carbon collection container 10 is made of bricks, it can create an environment more similar to that of an actual furnace (coke oven). The bricks are not particularly limited as long as they do not melt or expand excessively when exposed to approximately 1100°C, and examples include silica bricks, magnetic containers, and ceramic containers. Silica bricks are often used for the furnace walls of coke ovens, so silica bricks are particularly preferred. In other words, since the amount of carbon adhesion and the development of crystals are said to differ depending on the type of brick (Journal of the Fuel Society, Vol. 54, No. 576 (1975), pp. 250-256), silica bricks actually used in coke ovens are preferred.

[0041] As shown in FIG. 1, the furnace wall carbon collecting vessel 10 includes a sealed vessel 20 and a cylindrical spacer portion 22 sealed inside the sealed vessel 20.

[0042] The sealed container 20 is composed of a circular plate-shaped bottom 12, a hollow cylindrical coal burning section 14 arranged on the bottom 12, a hollow cylindrical furnace wall carbon deposition section 16 arranged on the coal burning section 14 and having the same inner and outer diameters as the coal burning section 14, and a circular plate-shaped lid 18 arranged on the furnace wall carbon deposition section 16.

[0043] The coal burning section 14 and the furnace wall carbon deposition section 16 are hollow cylindrical and have an outer diameter of 20 mm or more and 52 mm or less. The outer diameter is preferably 25 mm or more and 50 mm or less, and more preferably 30 mm or more and 50 mm or less. Because the outer diameters of the coal burning section 14 and the furnace wall carbon deposition section 16 are 20 mm or more and 52 mm or less, and are relatively small, coal can be carbonized in a short time. As a result, furnace wall carbon can be collected in a short time.

[0044] The coal burning section 14 and the furnace wall carbon deposition section 16 have wall thicknesses of 1 mm or more and 5 mm or less. The wall thickness is preferably 1 mm or more and 4 mm or less, and more preferably 1 mm or more and 3 mm or less. Because the wall thickness is 1 mm or more and 5 mm or less, and is relatively thin, it is easy for the external temperature to be transferred to the interior during carbonization. As a result, it is possible to carbonize the coal in a short time. The inner diameters of the coal burning section 14 and the furnace wall carbon deposition section 16 are calculated by subtracting the wall thickness from the outer diameter.

[0045] The height of the coal burning section 14 is 30 mm to 50 mm, preferably 30 mm to 48 mm, and more preferably 30 mm to 45 mm. Because the height of the coal burning section 14 is 30 mm to 50 mm, a relatively large amount of coal can be placed in the coal burning section 14. As a result, a large amount of furnace wall carbon can be collected. Furthermore, because the height of the coal burning section 14 is 30 mm to 50 mm, coke powder adheres to the coal burning section 14, and the adhesion of coke powder to the furnace wall carbon adhesion section 16 can be suppressed.

[0046] The height of the furnace wall carbon deposition portion 16 is 30 mm or more and 50 mm or less, preferably 30 mm or more and 45 mm or less, and more preferably 30 mm or more and 40 mm or less. The height of the furnace wall carbon deposition portion 16 is 30 mm or more and 50 mm or less, and furnace wall carbon adheres to this portion. This is clear from the examples. As a result, it is possible to collect a large amount of furnace wall carbon. The height of the coal burning section 14 and the height of the furnace wall carbon deposition section 16 may be the same or different.

[0047] The bottom 12 has a circular plate shape. The outer diameter of the bottom 12 (outer diameter in a plan view) is not particularly limited as long as it is the same as the outer diameter of the coal burning section 14 and the furnace wall carbon deposition section 16 or larger than the outer diameter of the coal burning section 14. For example, it can be 20 mm or more and 52 mm or less.

[0048] The thickness of the bottom 12 is not particularly limited, and may be, for example, 5 mm to 25 mm. However, in this embodiment, since it is preferable that heat is not easily transferred from the bottom 12 to the inside, the thickness is preferably 10 mm or more. Note that, in order to prevent heat from being transferred from the bottom 12, a heat insulating material 42 (see FIG. 2) may be provided between the bottom 12 and the heater 50. If the heat insulating material 42 is provided between the bottom 12 and the heater 50, it can also prevent the quartz glass test tube 40 from breaking due to the impact of loading when the furnace wall carbon collection container 10 is hot loaded into the quartz glass test tube 40 described below. When the heat insulating material 42 is provided between the bottom 12 and the heater 40, the thickness of the bottom 12 may be thin (for example, 20 mm to 50 mm).

[0049] The lid portion 18 has a circular plate shape. The outer diameter of the lid portion 18 (outer diameter in plan view) is not particularly limited as long as it is the same as the outer diameter of the coal burning portion 14 and the furnace wall carbon deposition portion 16 or larger than the outer diameter of the coal burning portion 14. For example, it can be 20 mm or more and 52 mm or less.

[0050] The thickness of the lid portion 18 is not particularly limited, but may be, for example, 5 mm or more and 25 mm or less, etc. However, in this embodiment, since it is preferable that heat is not easily transferred from the lid portion 18, it is preferable that the thickness is 10 mm or more.

[0051] It is preferable that a small through-hole (not shown) is provided in the lid portion 18. The size of the through-hole is preferably an outer diameter of 1 mm or more and 5 mm or less, more preferably 1 mm or more and 3 mm or less. The position of the through-hole is not particularly limited, but it can be, for example, the center of a circle in a plan view. By providing the through-hole, gas can be released through the through-hole, and the internal pressure can be prevented from becoming excessively high.

[0052] The spacer portion 22 is cylindrical, and its outer diameter is not particularly limited as long as the gap between the outer wall of the spacer portion 22 and the inner walls of the coal burning portion 14 and the furnace wall carbon deposition portion 16 is in the range of 1 mm to 5 mm. The gap between the outer wall of the spacer portion 22 and the inner walls of the coal burning portion 14 and the furnace wall carbon deposition portion 16 is preferably 1 mm to 5 mm, and more preferably 1 mm to 3 mm. For example, if the inner walls (inner diameter) of the coal burning portion 14 and the furnace wall carbon deposition portion 16 are 43 mm, the outer diameter of the spacer portion 22 is 33 mm to 41 mm. Regarding furnace wall carbon, the inventors have discovered that primary pyrolysis gas generated when coal softens and melts (around 350 to 500°C) comes into contact with the high-temperature furnace wall and is heated, causing secondary pyrolysis, which results in carbon adhering to the furnace wall. As a result, they have found that the most efficient way to collect a large amount of furnace wall carbon is to bring the primary pyrolysis gas into contact with a high-temperature object at the same time as it is generated. Therefore, the gap between the outer wall of the spacer section 22 and the inner walls of the coal burning section 12 and the furnace wall carbon deposition section 14 is set to 1 mm or more and 5 mm or less. As a result, the primary pyrolysis gas of coal can be brought into contact with the high-temperature coal burning section 12 and the furnace wall carbon deposition section 14 at the same time as it is generated, and the furnace wall carbon can be efficiently collected.

[0053] The height of the spacer portion 22 is 35 mm to 55 mm, preferably 35 mm to 45 mm, and more preferably 35 mm to 40 mm. The height of the furnace wall carbon deposition portion 16 is 30 mm to 50 mm, and furnace wall carbon deposits in this portion. As a result, it is possible to collect a large amount of furnace wall carbon.

[0054] As described above, the furnace wall carbon collecting container 10 makes it possible to collect a larger amount of furnace wall carbon in a shorter time.

[0055] Next, the method for collecting furnace wall carbon according to this embodiment will be described. Fig. 2 is a schematic diagram for explaining the method for collecting furnace wall carbon according to this embodiment.

[0056] The method for collecting furnace wall carbon according to this embodiment includes the following steps: A method for collecting furnace wall carbon using a furnace wall carbon collection container 10, A step A of placing coal between the bottom 12 of the furnace wall carbon collecting container 10 and the spacer portion 22; After the step A, a step B is performed in which the furnace wall carbon collecting container 10 having the coal disposed therein is charged into a heater 50 adjusted to a temperature range of 700°C or more and 1200°C or less; After the step B, the method includes a step C of removing the furnace wall carbon collecting container 10 from the heater 50 and obtaining the furnace wall carbon adhered to the furnace wall carbon adhering portion 16.

[0057] <Process A> In the method for collecting oven wall carbon according to this embodiment, first, coal 30 is placed between the bottom 12 of the oven wall carbon collection container 10 and the spacer portion 22. The coal 30 is the coal from which oven wall carbon is to be collected. That is, in the method for collecting oven wall carbon according to this embodiment, oven wall carbon generated from the coal 30 is collected.

[0058] <Process B> After step A, the furnace wall carbon collection container 10 containing the coal 30 is loaded into a heater 50 adjusted to a temperature range of 700°C to 1200°C. The furnace wall carbon collection container 10 may be directly placed in the heater 50, but it is preferable to first place a quartz glass test tube 40 with an inner diameter slightly larger than the outer diameter of the furnace wall carbon collection container 10 inside the heater 50, and then load the furnace wall carbon collection container 10 into this quartz glass test tube 40. When using a quartz glass test tube 40, it is preferable to place a heat insulating material 42 at the bottom of the quartz glass test tube 40. To collect a large amount of furnace wall carbon, it is efficient to bring the primary pyrolysis gas into contact with the high-temperature furnace wall carbon deposition portion 16 simultaneously with its generation; therefore, a large amount of primary pyrolysis gas is generated near the furnace wall carbon deposition portion 16, rather than at the bottom of the furnace wall carbon collection container 10.

[0059] The material of the heat insulating material 42 is not particularly limited, but examples thereof include high-temperature heat insulating boards. The thickness of the heat insulating material 42 is not particularly limited, but may be, for example, 20 mm to 50 mm, or 20 mm to 40 mm. The heat insulating material 42 plays a major role as a buffer material that prevents the quartz glass test tube 40 from breaking due to the impact of hot loading the furnace wall carbon collection container 10 into the quartz glass test tube 40, so there are no particular limitations on the material as long as it can withstand high temperatures. For example, Superwool, a product manufactured by Shin-Nihon Thermal Ceramics Co., Ltd., can be used.

[0060] The heater 50 is not particularly limited as long as it can be adjusted to a temperature range of 700° C. to 1200° C. and can accommodate the furnace wall carbon collection vessel 10 and the quartz glass test tube 40 .

[0061] Thereafter, carbonization is carried out within a temperature range of 700°C to 1200°C. The carbonization temperature is preferably 1000°C to 1150°C, more preferably 1100°C to 1150°C. The carbonization time is preferably 3 to 10 minutes, more preferably 3 to 5 minutes, after the temperature of the coal 30 (coal core temperature) reaches a predetermined temperature (within the carbonization temperature range). By setting the temperature range and carbonization time within the above range, primary pyrolysis gas can be suitably generated from the coal 30, and furnace wall carbon can be suitably collected.

[0062] <Process C> After the step B, the furnace wall carbon collecting container 10 is removed from the heater 50, and the furnace wall carbon adhered to the furnace wall carbon adhering portion 16 is obtained.

[0063] The entire furnace wall carbon collection container 10 or only the furnace wall carbon deposition portion 16 may be reused, and steps A to C may be repeated multiple times. This allows a larger amount of furnace wall carbon to be collected. When only the furnace wall carbon deposition portion 16 is reused, new parts may be used for the other parts.

[0064] As described above, according to the method for collecting furnace wall carbon of this embodiment, the furnace wall carbon collection container 10 is not heated from a low temperature (for example, about 300°C) (i.e., not semi-cold loading), but is loaded (hot loading) into the heater 50 that has been adjusted in advance to a temperature range of 900°C or higher and 1200°C or lower, making it possible to collect furnace wall carbon in a shorter time. Furthermore, according to the method for collecting oven wall carbon according to this embodiment, the oven wall carbon collection container 10 is used, so that it is possible to collect a larger amount of oven wall carbon in a shorter time.

[0065] The method for collecting furnace wall carbon according to this embodiment has been described above.

[0066] (Step 3) Next, a correlation equation between the amount of gas generated and the amount of carbon deposited is obtained from the amount of gas generated obtained in step 1 and the amount of carbon deposited in step 2.

[0067] In step 3, first, the amount of gas generated determined in step 1 and the amount of carbon adhesion determined in step 2 are plotted on a graph.

[0068] When the rate of thermal weight loss (TG) during heating from 150°C to 400°C is used as the amount of gas generated, the rate of thermal weight loss (TG) during heating from 150°C to 400°C obtained in step 1 above is plotted on the horizontal axis, and the amount of carbon adhesion obtained in step 2 above is plotted on the vertical axis. When the area of ​​the total ion chromatogram (TIC) during the temperature increase from 150°C to 400°C is used as the amount of gas generated, the area of ​​the total ion chromatogram (TIC) during the temperature increase from 150°C to 400°C obtained in step 1 is plotted on the horizontal axis, and the amount of carbon adhesion obtained in step 2 is plotted on the vertical axis.

[0069] Next, the plotted graph is fitted using the least squares method. The fitting method is performed as long as a certain degree of correlation is obtained (for example, the correlation coefficient R 2is 0.7 or more), examples of the method include, but are not limited to, linear fitting (linear approximation), linear approximation, quadratic approximation, etc. Among these, linear approximation is preferred because it tends to produce a correlation coefficient close to 1.

[0070] When linear fitting is performed, the correlation equation is expressed as follows: y=ae bx (where a and b are coefficients)

[0071] When linear approximation is performed, the correlation equation is expressed as follows: y=cx+d (where c and d are coefficients)

[0072] When quadratic approximation is performed, the correlation equation is expressed as follows: y=ex 2 +fx+g (where e, f, and g are coefficients)

[0073] The constants a to g are determined by performing fitting.

[0074] Correlation coefficient R 2 is preferably 0.7 or more, and more preferably 0.8 or more. 2 If the correlation is 0.7 or higher, it can be said that the correlation is sufficiently high.

[0075] (Step 4) Next, the gas generation rate of the coal to be evaluated (thermal weight loss rate (TG) when the temperature is increased from 150°C to 400°C, or total ion chromatogram (TIC) when the temperature is increased from 150°C to 400°C) is determined. In step 4, the gas generation rate of the coal to be evaluated is determined using the same method as in step 2 above.

[0076] (Step 5) Next, an estimated carbon deposition amount of the coal to be evaluated is determined from the gas generation amount of the coal to be evaluated determined in step 4 and the correlation equation obtained in step 3. Specifically, the estimated carbon deposition amount of the coal to be evaluated is determined by substituting the gas generation amount of the coal to be evaluated determined in step 4 into the correlation equation obtained in step 3. As mentioned above, there is a high correlation between the thermal weight loss (TG) during the temperature rise from 150°C to 400°C and the amount of carbon adhesion. In addition, there is a high correlation between the total ion chromatogram (TIC) and the amount of carbon deposition when the temperature is increased from 150°C to 400°C. Therefore, the estimated carbon deposition amount of the coal to be evaluated can be said to be highly accurate.

[0077] According to this embodiment, the correlation equation is obtained from the evolved gas and the amount of carbon, rather than using various factors, which is simple. Furthermore, by measuring the amount of evolved gas in the range of 150 to 400°C, the estimated amount of carbon deposition on the coal to be evaluated can be obtained, allowing results to be obtained quickly. [Example]

[0078] The present invention will be described in detail below using examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention.

[0079] [Creating correlation equations] (Process 1) Several coals (29 types) were prepared for creating the correlation equation. The prepared coals for creating the correlation equation were pulverized to 0.15 mm or less using a ball mill (model: PM100) manufactured by Retsch. Next, using a Rigaku TG-DTA system (model: TG-DTA8122 / IRH-ASC) and a JEOL GC-MS system (model: JMS-Q1500GC), approximately 10 mg of sample, crushed to 0.15 mm or less, was heated from room temperature to 100°C at a rate of 10°C / min under a 300 mL / min He gas flow. After holding at 100°C for 10 minutes, the temperature was increased at a rate of 10°C / min to 1000°C and held at 1000°C for 5 minutes. The thermal weight loss (TG) and total ion chromatogram (TIC) area were measured during the heating from 150°C to 400°C. The ion charge range (m / z) was 12 to 500.

[0080] (Process 2) <Preparing the furnace wall carbon collection container> First, a furnace wall carbon collection container made of silica bricks was prepared. The dimensions of the prepared furnace wall carbon collection container were as follows:

[0081] Bottom: circular plate, outer diameter 50 mm, height (thickness) 10 mm Coal burning section: hollow cylinder, outer diameter 50 mm, inner diameter 43 mm, height 45 mm Furnace wall carbon adhesion part: hollow cylindrical, outer diameter 50 mm, inner diameter 43 mm, height 30 mm Lid: circular plate, outer diameter 50 mm, height (thickness) 10 mm, with a through hole of outer diameter 2.5 mm in the center in plan view Spacer part: cylindrical, outer diameter 40 mm, height 40 mm

[0082] The furnace wall carbon collection container was manufactured as follows. First, a silica brick (Yotai refractory brick 476AK / 476BK) was bored into a hollow cylinder (outer diameter 50 mm, inner diameter 43 mm) using a drilling machine [cutting jig: Maruto diamond core bit]. The hollow cylinder was then cut into a 30 mm high piece (for the carbon deposit part on the furnace wall) and a 45 mm high piece (for the coal burning part) using a cutting machine [Refine Tech Refine Cutter RCA-237]. In addition, from the waste material generated during this process, a bottom part with an outer diameter of 50 mm and a thickness of 10 mm, a lid part with an outer diameter of 50 mm and a thickness of 10 mm, and a cylindrical spacer part with an outer diameter of 40 mm and a height of 40 mm were made. A through hole with an outer diameter of 2.5 mm was drilled in the center of the circular plate (center in plan view) of the lid using a concrete drill bit.

[0083] <Collecting furnace wall carbon> First, the weight of the bricks in the carbon-adhered portion of the furnace wall was measured. Next, the coal-burning unit was placed on the bottom so that the periphery of the bottom coincided with the periphery of the coal-burning unit, and the bottom and the coal-burning unit were fixed with cellophane tape (registered trademark). Next, 38 g of a coal sample (coal for creating a correlation equation) with a bulk density (BD) of 0.94 dry-g / cm was placed in the coal-burning unit. 3 The coal was packed so that the height of the coal in the container was about 30 mm.

[0084] Next, a spacer was placed on top of the coal sample. Next, the furnace wall carbon deposition portion was placed on the coal firing portion so that the outer periphery of the coal firing portion coincided with the outer periphery of the furnace wall carbon deposition portion, and the coal firing portion and the furnace wall carbon deposition portion were fixed together with Cellophane Tape (registered trademark). Furthermore, a lid was placed on the furnace wall carbon deposition portion so that the outer periphery of the furnace wall carbon deposition portion coincided with the outer periphery of the lid, and the furnace wall carbon deposition portion and the lid were fixed together with Cellophane Tape (registered trademark).

[0085] A 40 mm thick heat insulating material (product name: Superwool, manufactured by Nippon Thermal Ceramics Co., Ltd.) was placed at the bottom of a quartz glass test tube with an inner diameter of 50 mm. This quartz glass test tube was placed in a test tube furnace (manufactured by Osaka Seiko Co., Ltd.) and heated to 1000°C and maintained at that temperature. The test tube furnace corresponds to the heater of the present invention.

[0086] Next, the furnace wall carbon collection container containing the coal sample was loaded (hot loading) into a quartz glass test tube and carbonized for 20 minutes. After that, the furnace wall carbon collection container was removed from the test tube furnace (heating furnace) while N2 gas was flowing into the quartz glass test tube, and allowed to cool to 150°C. Note that the cooling was carried out while N2 gas was flowing into the furnace wall carbon collection container through the through-hole in the lid. The cellophane tape (registered trademark) was used to secure each part (each component) of the furnace wall carbon collection container to each other before inserting it into the quartz glass test tube. It will be carbonized and peeled off when heated to 1000°C, but this will not affect the collection of furnace wall carbon.

[0087] After cooling to 150°C, the bricks at the carbon-adhered portion of the furnace wall were weighed, and the weight of the adhering carbon was calculated from the difference between the weight of the bricks at the carbon-adhered portion of the furnace wall before carbonization.

[0088] The carbonization test was carried out while a thermocouple was inserted into the coal sample to monitor the temperature at the center of the coal sample.

[0089] The same procedure was repeated using the furnace wall carbon collection container used above (furnace wall carbon collection container with carbon still attached). That is, 38 g of coal sample was filled into the coal baking section, the bottom of which and the coal baking section were fixed with cellophane tape (registered trademark), a spacer was placed on top of the coal sample, the furnace wall carbon adhesion section with carbon from the first carbonization still attached was placed on top of the coal baking section, a lid was placed on the furnace wall carbon adhesion section, and the furnace wall carbon collection container containing the coal sample was placed (hot loading) into a quartz glass test tube kept at 1000°C, carbonized for 20 minutes, and allowed to cool to 150°C. A total of three dry distillations were carried out. The total carbon deposition amount obtained in the three dry distillations was used as the carbon deposition amount determined in step 2.

[0090] (Step 3) The amount of gas generated determined in step 1 and the amount of carbon adhesion determined in step 2 were plotted on a graph. Specifically, the thermal weight loss (TG) during the temperature increase from 150°C to 400°C determined in step 1 was plotted on the horizontal axis, and the amount of carbon adhesion determined in step 2 was plotted on the vertical axis (FIG. 3). Furthermore, the area of ​​the total ion chromatogram (TIC) during the temperature increase from 150°C to 400°C determined in step 1 was plotted on the horizontal axis, and the amount of carbon adhesion determined in step 2 was plotted on the vertical axis (FIG. 4). FIG. 3 is a graph showing the relationship between the thermal weight loss rate (TG) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C. FIG. 4 is a graph showing the relationship between the total ion chromatogram (TIC) and the amount of carbon deposition when the temperature is increased from 150° C. to 400° C.

[0091] Next, linear fitting was performed using the least squares method on the graphs in Figures 3 and 4. As a result, in Figure 3, y=0.7932e 0.4454x , correlation coefficient R 2 =0.9232. In Figure 4, y=1.0301e (2E-07)x , correlation coefficient R 2 =0.8206 (note that "2E-07" means 2 x 10 to the -7th power). From these results, it can be said that there is a high correlation between the thermal weight loss (TG) and carbon deposition amount when the temperature is increased from 150°C to 400°C. In addition, it can be said that there is a high correlation between the total ion chromatogram (TIC) and carbon deposition amount when the temperature is increased from 150°C to 400°C.

[0092] In addition, using the same plots as in Figures 3 and 4, linear approximation (fitting) by the least squares method is shown in Figures 5 and 6. FIG. 5 is a graph showing the relationship between the thermal weight loss rate (TG) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by performing linear fitting using the least squares method. FIG. 6 is a graph showing the relationship between the total ion chromatogram (TIC) and the amount of carbon deposition when the temperature is increased from 150° C. to 400° C., and is a graph obtained by linear fitting using the least squares method. As a result, in Figure 5, y=1.2932x-0.5247, correlation coefficient R 2 =0.833. In Figure 6, y=(5E-07)x+0.1239, correlation coefficient R 2 =0.7243 (note that "5E-07" means 5 x 10 to the -7th power). From these results, it can be said that even when linear fitting is performed, there is a high correlation between the thermal weight loss (TG) and carbon deposition amount when the temperature is increased from 150°C to 400°C. In addition, there is a high correlation between the total ion chromatogram (TIC) and carbon deposition amount when the temperature is increased from 150°C to 400°C.

[0093] In addition, using the same plots as in Figures 3 and 4, quadratic approximation (fitting) by the least squares method is shown in Figures 7 and 8. FIG. 7 is a graph showing the relationship between the thermal weight loss rate (TG) and the amount of carbon adhesion when the temperature is increased from 150° C. to 400° C., and is a graph obtained by performing quadratic fitting using the least squares method. FIG. 8 is a graph showing the relationship between the total ion chromatogram (TIC) and the amount of carbon deposition when the temperature is increased from 150° C. to 400° C., and is a graph obtained by performing quadratic fitting using the least squares method. As a result, in Figure 7, y=0.4041x 2 -0.8545x+1.9408, correlation coefficient R 2 =0.9249. In Figure 8, y=(6E-14)x 2 -(7E-08)x+1.3746, correlation coefficient R 2 =0.8331 (Note that "6E-14" means 6 x 10 to the -14th power, and "7E-08" means 7 x 10 to the -8th power). . From these results, it can be said that there is a high correlation between the thermal weight loss (TG) and carbon deposition amount when the temperature is increased from 150°C to 400°C, even when quadratic fitting is performed. In addition, it can be said that there is a high correlation between the total ion chromatogram (TIC) and carbon deposition amount when the temperature is increased from 150°C to 400°C.

[0094] From the above, by using the correlation equation with high correlation thus created, when the gas generation amount of the coal to be evaluated (thermal weight loss rate (TG) when the temperature is raised from 150°C to 400°C or total ion chromatogram (TIC) when the temperature is raised from 150°C to 400°C) is determined, the carbon deposition amount corresponding to this gas generation amount can be determined.

[0095] [Verification of the relationship between VM and carbon deposition amount] The relationship between VM and carbon deposition was confirmed using multiple coals (29 types) used to create the correlation equation. FIG. 9 is a graph showing the relationship between VM and the amount of carbon deposition. As can be seen from Figure 9, even if the VM is roughly the same, there are coals with different amounts of carbon deposition, and it cannot be said that there is a sufficient correlation between VM and carbon deposition. 2 =0.5773. [Explanation of symbols]

[0096] 10. Furnace wall carbon collection container 12 Bottom 14 Coal Burning Section 16 Carbon deposits on furnace wall 18 Lid 20. Airtight containers 22 Spacer part 30 Coal 40 Quartz glass test tubes 42 Insulation 50 Heater

Claims

1. Step 1: determining the amount of gas generated when a temperature of a plurality of coals for use in creating a correlation equation is increased from 150°C to 400°C; Step 2: determining the carbon deposition amount of a plurality of coals for creating the correlation equation using the furnace wall carbon collection method described below; a step 3 of obtaining a correlation equation between the amount of gas generated and the amount of carbon deposited from the amount of gas generated obtained in the step 1 and the amount of carbon deposited in the step 2; Step 4: determining the gas generation rate of the coal to be evaluated; a step 5 of calculating an estimated carbon deposition amount of the coal to be evaluated from the gas generation amount of the coal to be evaluated calculated in the step 4 and the correlation equation obtained in the step 3; A method for estimating carbon deposition amount, comprising: <Method for collecting furnace wall carbon> Providing a furnace wall carbon collection container, The furnace wall carbon collection container is It is made up of bricks, a sealed container including a circular plate-shaped bottom, a hollow cylindrical coal burning unit disposed on the bottom, a hollow cylindrical furnace wall carbon deposition unit disposed on the coal burning unit and having the same inner and outer diameters as the coal burning unit, and a circular plate-shaped lid disposed on the furnace wall carbon deposition unit; a cylindrical spacer portion enclosed in the sealed container; Equipped with The outer diameters of the coal burning section and the furnace wall carbon deposition section are 20 mm or more and 52 mm or less, The wall thickness of the coal burning section and the furnace wall carbon deposition section is 1 mm or more and 5 mm or less, The height of the coal burning section is 30 mm or more and 50 mm or less, The height of the carbon deposition portion on the furnace wall is 30 mm or more and 50 mm or less, a gap between an outer wall of the spacer portion and an inner wall of the coal burning portion and the furnace wall carbon deposition portion is 1 mm or more and 5 mm or less; a step X in which the height of the spacer portion is 35 mm or more and 55 mm or less; A step A of placing coal between the bottom of the furnace wall carbon collecting container and the spacer portion; After the step A, a step B is performed in which the furnace wall carbon collection container having the coal disposed therein is charged into a heater adjusted to a temperature range of 700°C or higher and 1200°C or lower; After the step B, a step C is performed in which the furnace wall carbon collecting container is removed from the heater, and the furnace wall carbon adhering to the furnace wall carbon adhering portion is obtained. A method for collecting furnace wall carbon comprising:

2. 2. The method for estimating carbon deposition amount according to claim 1, wherein the amount of gas generated is a value determined by thermogravimetry when the temperature of coal is raised from 150°C to 400°C.

3. 2. The method for estimating carbon deposition mass according to claim 1, wherein the amount of gas generated is a value determined from the area of ​​a total ion chromatogram (TIC) obtained by mass spectrometry of gas generated when coal is heated from 150°C to 400°C.

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