Method for quantifying gas generated from coal, method for estimating gas generation amount during coal carbonization, and method for manufacturing coke

Abstract

To accurately quantify gas generated during coal heating.SOLUTION: Gas generated when heating coal is collected. The collected gas is introduced into a separation column 3 of the gas chromatograph. The gas introduced into the separation column 3 is trapped by cooling the separation column 3 using a cooling unit 5. Cooling of the separation column 3 is released to release the trapped gas. At this time, it is preferable to use a heating unit 4 to heat the separation column 3, which has been released from cooling, to raise its temperature. The released gas is analyzed by a mass spectrometer 7 and quantified.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for quantifying gas generated from coal, a method for estimating the amount of gas generated during coal carbonization, and a method for producing coke. [Background technology]

[0002] Coal remains an important fossil fuel even today due to its long lifespan and low price. Coal is primarily used as a raw material for coke used in steelmaking and as fuel for thermal power plants, and consumption is steadily increasing.

[0003] One of the challenges in using coal is dealing with the gases that are produced when it is heated. In particular, sulfur-based gases derived from sulfur (S) contained as an impurity in coal are not only highly toxic, but are also said to contribute to acid rain and the greenhouse effect. For this reason, strict management of sulfur-based gases is required, including the setting of regulatory limits. In Japan, coke ovens and coal-fired power plants that produce coke by carbonizing coal are equipped with high-performance desulfurization equipment.

[0004] Generally, sulfur in coal is considered an impurity, and the total sulfur concentration (Total-S, TS) is one of the important indicators of coal quality. When using coal, of course, high-quality coal with a low TS is required, but due to the increase in demand for coal in recent years, coal prices, especially those with a low sulfur concentration (low-sulfur coal), have continued to rise. Furthermore, because low-sulfur coal is only produced in limited areas such as Australia, concentrating on specific brands carries the risk that stable procurement may become difficult due to factors such as weather problems in the producing areas and supply and demand trends in other countries.

[0005] Against this background, the use of inexpensive coal with a high sulfur concentration (high-sulfur coal) is being considered. However, using high-sulfur coal means that the amount of sulfur gases generated per unit of consumption increases. This would place a heavy load on existing desulfurization equipment, leading to increased desulfurization costs. Furthermore, if sulfur-based gases are generated in excess of the desulfurization capacity, they may be released into the environment, potentially causing environmental pollution. Therefore, it is important to understand the temperature (temperature range) and amount of sulfur-based gases generated during coal carbonization for each brand of coal, and then select it as a coke feedstock or fuel for thermal power plants.

[0006] The temperature (temperature range) at which sulfur-containing gases are generated during coal heating and the amount of sulfur gases generated depend on the form of sulfur present in the coal. Sulfur in coal exists in various forms, such as inorganic sulfur and organic sulfur, and the ratio of these forms varies depending on the coal brand. There are two types of inorganic sulfur: sulfate sulfur and pyrite sulfur. Examples of organic sulfur include thiophene, sulfide, thiol, and sulfonic acid.

[0007] Patent Document 1 discloses a technology in which "coal is heated from room temperature to 1000°C in an inert gas, and sulfur-containing gases generated by thermal decomposition of sulfur compounds are continuously monitored and measured to quantify the sulfur in the coal by its form of existence" ([Claim 1]). More specifically, in the technique disclosed in Patent Document 1, for example, "mass spectrometry" is used to monitor gas (

[0033] ). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-257920 Summary of the Invention [Problem to be solved by the invention]

[0009] When sulfur-based gases are quantified using "mass spectrometry" in the technique disclosed in Patent Document 1, there is a possibility that accurate evaluation cannot be performed due to overlap with hydrocarbon-based gases that do not contain sulfur.

[0010] The present invention has been made in view of the above points, and has as its object to accurately quantify gases (particularly sulfur-based gases) generated when coal is heated. [Means for solving the problem]

[0011] As a result of extensive research, the present inventors have found that the above object can be achieved by employing the following configuration, and have completed the present invention.

[0012] That is, the present invention provides the following [1] to [6]. [1] A method for quantifying gas generated from coal, comprising: a gas collection step of collecting gas generated when coal is heated; a gas introduction step of introducing the gas collected in the gas collection step into a separation column of a gas chromatograph; a gas capture step of cooling the separation column to capture the gas introduced into the separation column; a gas release step of removing the cooling of the separation column and releasing the gas captured in the gas capture step; and an analysis step of analyzing and quantifying the gas released in the gas release step using a mass spectrometer. [2] The quantitative method according to [1] above, further comprising a heating step of heating the separation column after cooling has been removed. [3] The quantitative determination method according to [1] or [2] above, wherein the gas contains a sulfur-based gas. [4] A method for estimating the amount of gas generated during coal carbonization, which estimates the generation temperature or temperature range and generation amount of sulfur-based gas generated during coal carbonization based on the quantitative results obtained by the quantitative method described in [3] above. [5] A method for producing coke by carbonizing coal, in which the coke production conditions are changed based on the estimation results obtained by the estimation method described in [4] above. [6] The method for producing coke according to [5] above, wherein the production condition is a coal blending ratio. [Effects of the Invention]

[0013] According to the present invention, the amount of gas generated when coal is heated can be accurately determined. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram showing an apparatus used to quantify gas generated from coal. [Figure 2] 1 is a graph showing the amount of hydrogen sulfide (H2S) generated in each heating temperature range. [Figure 3] 1 is a graph showing the amount of sulfur dioxide (SO2) generated in each heating temperature range. DETAILED DESCRIPTION OF THE INVENTION

[0015] [Method for quantifying gases generated from coal] The method for quantifying gas generated from coal according to this embodiment (hereinafter, for convenience, also referred to as "this quantification method") comprises a gas collection step of collecting gas generated when coal is heated, a gas introduction step of introducing the gas collected in the gas collection step into a separation column of a gas chromatograph, a gas capture step of cooling the separation column to capture the gas introduced into the separation column, a gas release step of removing the cooling of the separation column and releasing the gas captured in the gas capture step, and an analysis step of analyzing and quantifying the gas released in the gas release step using a mass spectrometer.

[0016] <Devices used to quantify gases generated from coal> FIG. 1 is a schematic diagram showing an apparatus 1 used for quantifying the amount of gas generated from coal. The apparatus 1 includes a chamber 2. Inside the chamber 2, there are provided a gas chromatograph separation column 3, a heating section 4 that heats the separation column 3, and a cooling section 5 that cools at least a portion of the separation column 3 in the longitudinal direction. Furthermore, the device 1 includes a gas injection unit 6 that injects gas into the separation column 3, and a mass analysis unit 7 that separates and identifies the gas components contained in the gas introduced from the separation column 3 according to their mass-to-charge ratios.

[0017] The heating method of the heating unit 4 is not particularly limited as long as it is possible to control the temperature when heating the separation column 3, and examples thereof include a heating furnace method using a resistance heater and a high-frequency induction heating method.

[0018] The cooling method of the cooling section 5 is not particularly limited as long as it can cool at least a part of the separation column 3 and control the temperature at any desired level, and examples thereof include conventionally known methods such as a Peltier cooling method and a liquid nitrogen cooling method. The cooling range of the cooling section 5 is not particularly limited, but it is preferable that the cooling section 5 can cool a range of at least about 10 mm in length in the separation column 3. A cryotrap is a suitable example of such a cooling unit 5. The cryotrap is a facility that is placed midway along the separation column 3 and blows nitrogen gas cooled with liquid nitrogen onto the separation column 3 from the outside.

[0019] When a cryotrap is used as the cooling unit 5, the type and polarity of the separation column 3 may be freely selected since the cryotrap has a high separation ability.

[0020] The apparatus 1 may further comprise a pyrolysis furnace 8. The pyrolysis furnace 8 is used to heat the coal to generate gas from the coal. The pyrolysis furnace 8 may have any heating capacity that corresponds to the heating temperature of the coal fed into the pyrolysis furnace 8. The heating method of the pyrolysis furnace 8 may be a conventionally known method, such as a filament type that uses a filament for heating, an induction heating type that uses a high-frequency magnetic field to heat an alloy sample foil, or a heating furnace type.

[0021] Each step of the present quantification method carried out using the apparatus 1 will be described in detail below.

[0022] <Gas collection process> The gas collecting step is a step of collecting gas generated when coal is heated. In the gas collection step, it is preferable to heat coal by charging it into the pyrolysis furnace 8. In this way, gas generated from the heated coal is collected inside the pyrolysis furnace 8. When simulating the atmosphere during coal carbonization in a coke oven, the atmosphere inside the pyrolysis furnace 8 is preferably an inert gas atmosphere to avoid peak overlap in the mass analysis unit 7. As the inert gas, helium (He) is preferred, but nitrogen (N2) or the like may also be used.

[0023] "coal" The coal fed into the pyrolysis furnace 8 is preferably pulverized to a certain particle size or less to prevent temperature unevenness during heating. Specifically, the particle size of the coal is preferably 250 μm or less, and more preferably 125 μm or less. If the particle size of the coal is too large, uniform heating becomes difficult, which can cause unevenness in the amount of gas generated, potentially reducing the analytical accuracy of the mass spectrometer 7. Furthermore, in order to reduce the influence of moisture on the mass spectrometric section 7, it is preferable to use coal that has been thoroughly air-dried. An amount of coal is charged into the pyrolysis furnace 8 in accordance with the volume of the pyrolysis furnace 8. However, if too much coal is charged into the pyrolysis furnace 8, a large amount of gas will be trapped in the separation column 3 by the cooling section 5, which may cause clogging of the separation column 3. For this reason, the amount of coal charged into the pyrolysis furnace 8 is preferably about 70 to 80% of the volume of the pyrolysis furnace 8.

[0024] <Gas generated when coal is heated> The gases evolved during coal heating are hydrogen and hydrocarbons with various molecular weights (C m H n ) are contained in the low molecular weight hydrocarbons, such as methane (CH4), ethane (C2H6), and ethylene (C2H4). High molecular weight hydrocarbons include n-hexane (C6H 14 ), n-decane (C 10 H 22 ) and m>10 may also be used. The gases generated during coal heating also contain sulfur-based gases, such as hydrogen sulfide (H2S), carbonyl sulfide (COS), sulfur dioxide (SO2), carbon disulfide (CS2), and thiophene (C4H4S).

[0025] <<Preheating process>> Among the gases generated during coal heating, the gases generated at a specific heating temperature A or heating temperature range B may be quantified. In this case, it is preferable to provide a step (preheating step) in which coal is heated in advance at a temperature (preheating temperature) lower than the heating temperature A or the lower limit temperature of the heating temperature range B, and the generated gas is discharged.

[0026] The preheating temperature may be set in consideration of the control range of the temperature inside the pyrolysis furnace 8. For example, if the control range is less than 5°C, the preheating temperature is set 5°C lower than the lower limit of heating temperature A or heating temperature range B. The time for heating the coal at the preheating temperature may be any time that allows the coal to stop generating gas when heated at the preheating temperature, and is, for example, 10 minutes or more, preferably 15 minutes or more.

[0027] The route for discharging the gas generated in the preheating step is not particularly limited, and may be discharged from a split route (not shown) or may be passed through the separation column 3 of a gas chromatograph and then discharged. When passing through the separation column 3, it is preferable to confirm that no gas is detected by the mass spectrometric unit 7 before the gas collection step.

[0028] When quantifying the gas generated at heating temperature A, after the preheating step, coal is heated for a certain period of time in pyrolysis furnace 8 set at heating temperature A to generate gas. If the heating time is too short, all of the coal may not be heated sufficiently, and all of the gas generated at heating temperature A may not be collected. For this reason, the heating time is preferably 10 minutes or more, and more preferably 15 minutes or more.

[0029] When quantifying the gas generated in heating temperature range B, after the preheating step, the temperature inside the pyrolysis furnace 8 is raised from the lower limit temperature to the upper limit temperature of heating temperature range B to generate gas from the coal. If the temperature increase rate is too fast, the coal may not be heated sufficiently at each temperature during the temperature increase process, and it may not be possible to capture all of the gas generated throughout the entire heating temperature range B. For this reason, the temperature increase rate is preferably 10°C / min or less, and more preferably 5°C / min or less. After the temperature increasing step, a step of heating at the upper limit temperature may be added.

[0030] <Gas introduction process> In the gas introduction step, the gas collected in the gas collection step is introduced into the separation column 3 of the gas chromatograph from the gas injection part 6 using a carrier gas. The gas introduced into the separation column 3 flows together with the carrier gas from one end of the separation column 3 (the end on the gas injector 6 side) to the other end (the end on the mass spectrometer 7 side). As the carrier gas, an inert gas is preferable to simulate a coke oven, and He gas is more preferable because it has little effect on the mass spectrometer 7. The flow rate and split ratio of the carrier gas are not particularly limited and may be adjusted appropriately depending on the analytical sensitivity of the mass spectrometer 7, etc.

[0031] <Gas Trapping Process> In the gas trapping step, the cooling unit 5 (for example, a cryotrap) is operated to cool at least a portion of the separation column 3 in the longitudinal direction to a constant cooling temperature. Hereinafter, for convenience, the part of the separation column 3 that is cooled by the cooling section 5 may be referred to as the "part to be cooled," and the part of the separation column 3 that is not the part to be cooled may be referred to as the "part not to be cooled." The gas introduced into separation column 3 is solidified in the cooling target portion of separation column 3 by operation of cooling unit 5 , and is captured inside separation column 3 .

[0032] For example, consider a case where the gas introduced into separation column 3 is a sulfur-based gas. Among the gas components contained in the sulfur-based gas, hydrogen sulfide has the lowest boiling point of -60°C, so the cooling temperature of separation column 3 is set to a temperature lower than -60°C. As a result, while cooling unit 5 is operating, all gas components with boiling points of -60°C or higher are captured in separation column 3.

[0033] Consider the case where the gas introduced into the separation column 3 is the gas generated when coal is heated. Among the gas components contained in the gas generated when coal is heated, gas components other than sulfur-based gases include, for example, hydrogen (boiling point: -252.6°C); low molecular weight hydrocarbons such as methane (boiling point: -162°C), ethylene (boiling point: -103.7°C), and ethane (boiling point: -89°C); and high molecular weight hydrocarbons such as n-hexane (boiling point: 69°C) and n-decane (boiling point: 174°C). Of these, gas components (such as hydrogen and low molecular weight hydrocarbons) with boiling points lower than the cooling temperature of the separation column 3 pass through the separation column 3 without being captured therein. On the other hand, gas components (such as high molecular weight hydrocarbons) having a boiling point equal to or higher than the cooling temperature of the separation column 3 are all captured in the separation column 3 together with the sulfur-containing gases.

[0034] The time for cooling the cooling target part of the separation column 3 is not particularly limited, and is, for example, about 30 seconds to 1 minute.

[0035] The temperature inside the chamber 2 (i.e., the temperature of the non-cooled portion of the separation column 3) is preferably 100° C. or less, more preferably 80° C. or less, and even more preferably 50° C. or less. On the other hand, the lower limit is not particularly limited and is, for example, room temperature (e.g., 25° C.). The temperature inside the chamber 2 is controlled by operating the heating unit 4 .

[0036] If the temperature inside the chamber 2 is within the above range, the temperature gradient between the cooled and non-cooled parts of the separation column 3 becomes gentle when the cooling unit 5 is in operation. This widens the range of influence of the cooling unit 5 (i.e., the cooled parts of the separation column 3), and reduces analytical errors in the mass spectrometry unit 7 in the analysis step described below. In the subsequent gas release step, the temperature inside the chamber 2 is also preferably within the above range for reasons that will be described later.

[0037] <Gas release process> In the gas release step, the cooling of the separation column 3 is stopped and the trapped gas is released. Cooling is stopped by turning off the operation of the cooling unit 5 (for example, a cryotrap). This causes the temperature of the cooling target portion of the separation column 3 to rise, and the solidified gas components volatilize. At this time, gas components volatilize in order from those with the lowest boiling points, progress through the separation column 3, and are introduced into the mass analysis unit 7 with a time lag. This is because the effect of the difference in boiling points on the separation ability is greater than the effect of the separation ability due to the column polarity.

[0038] Gas components reach the mass spectrometer 7 in order of lowest boiling point. Therefore, low molecular weight hydrocarbons (hydrocarbon-based gases) are introduced into the mass spectrometer 7 first, followed by volatilized sulfur-based gases, and finally high molecular weight hydrocarbons (hydrocarbon-based gases). Low molecular weight hydrocarbon gases such as methane, ethane, and ethylene have a smaller mass-to-charge ratio (m / z) than sulfur-based gases, so no peaks overlapping with sulfur-based gases are generated. On the other hand, when a high molecular weight hydrocarbon gas is ionized in the mass spectrometer 7, it generates fragment ions with the same mass-to-charge ratio (m / z) as the sulfur-based gas. As a result, peaks overlapping with the sulfur-based gas occur, making it impossible to accurately separate the peaks of the sulfur-based gas. However, in this embodiment, the high-molecular-weight hydrocarbon gas is introduced into the mass spectrometer 7 after the sulfur-based gas. This allows the sulfur-based gas to be analyzed in the mass spectrometer 7 while avoiding peak overlap caused by the high-molecular-weight hydrocarbon gas that does not contain sulfur. In other words, the sulfur-based gas generated during coal heating can be quantified with high accuracy.

[0039] However, if the temperature inside the chamber 2 (the temperature of the non-cooled part of the separation column 3) is too high (for example, 300°C) during the gas release process, the rate at which the temperature of the cooled part of the separation column 3 rises may become too fast after cooling is released. In this case, not only the sulfur-based gas but also the high-molecular-weight hydrocarbon-based gas that affects the analysis of the sulfur-based gas quickly reaches the temperature inside the chamber 2 and is likely to volatilize. This makes it easier for the two to overlap in the mass analysis unit 7, which may result in insufficient quantitative accuracy of the sulfur-based gas.

[0040] Therefore, even in the gas releasing step, the temperature inside the chamber 2 is preferably within the above-mentioned range. That is, the temperature inside the chamber 2 is preferably 100°C or less, more preferably 80°C or less, and even more preferably 50°C or less. This slows down the rate at which the temperature of the cooling target portion of the separation column 3, from which cooling has been released, rises, and as a result, sulfur-based gases with low boiling points volatilize and are more likely to be introduced into the mass spectrometric unit 7 before high-molecular-weight hydrocarbon gases that affect the analysis of sulfur-based gases. In other words, it becomes easier to accurately quantify the sulfur-based gases generated when coal is heated.

[0041] <Temperature-raising heating process> In addition to the gas releasing step, the present quantitative method preferably further comprises a temperature increasing / heating step of heating the separation column 3. Specifically, for example, the cooling of the separation column 3 is released and the temperature of the separation column 3 is increased by heating. The temperature of the separation column 3 is increased by operating the heating unit 4 and heating the inside of the chamber 2. The temperature rise rate at this time is, for example, 5° C. / min or more. On the other hand, for the reasons mentioned above, it is preferable that the temperature rise rate is not too high, specifically, 20°C / min or less is preferable, 15°C / min or less is more preferable, and 10°C / min or less is even more preferable.

[0042] <Analysis process> In the analysis step, the gas (sulfur-based gas) released in the gas release step is analyzed and quantified by the mass spectrometer 7.

[0043] In the mass analysis section 7, the gas components contained in the sulfur-based gas released in the gas releasing step are separated and identified according to their mass-to-charge ratios. In this embodiment, a mass spectrum of a single peak is obtained at each mass-to-charge ratio (m / z) for the main low-molecular-weight gas components contained in sulfur-based gases: hydrogen sulfide (HS, m / z: 34), carbonyl sulfide (COS, m / z: 60), sulfur dioxide (SO, m / z: 64), carbon disulfide (CS, m / z: 76), and thiophene (CHS, m / z: 84). The size of the peak area allows one to grasp the tendency of the amount of each gas component. Separately, the peak areas of each gas component with known concentrations obtained under the same conditions are used as a calibration curve to quantify each gas component.

[0044] After the analysis in the mass spectrometric unit 7 is completed, it is preferable to operate the heating unit 4 to heat the inside of the chamber 2 in order to remove hydrocarbons remaining inside the separation column 3. At this time, the temperature inside the chamber 2 is preferably 200°C or higher, and more preferably 300°C or higher.

[0045] [Method for estimating gas generation rate during coal carbonization and method for producing coke] Next, a method for estimating the amount of gas generated during coal carbonization according to this embodiment (hereinafter also referred to as "this estimation method") will be described. The following description also serves as a description of the coke manufacturing method according to this embodiment (hereinafter also referred to as "this manufacturing method").

[0046] In this estimation method, first, the above-described present quantification method is carried out to quantify the amount of sulfur-based gases generated when coal is heated. At this time, as shown in the Examples described below, it is preferable to quantify each of the gas components (hydrogen sulfide, sulfur dioxide, etc.) contained in the sulfur-based gas generated when coal is heated.

[0047] It is also preferable to repeatedly carry out the above-described present quantification method. In this case, as shown in the Examples described below, in the gas collection step, coal is heated at a plurality of different heating temperatures or heating temperature ranges, and the generated gas is collected.

[0048] Next, based on the obtained quantitative results, the temperature or temperature range at which sulfur-containing gases are generated and the amount of sulfur-containing gases generated when coal is carbonized in a coke oven are estimated.

[0049] When n types of coal are blended, charged into a coke oven, and carbonized, the amount of sulfur-containing gas generated F(T) is expressed by, for example, the following formula. F(T)=A1×f1(T)+A2×f2(T)+···+A n ×f n (T) In the above formula, f n (T) is a function of temperature that indicates the amount of sulfur gas generated by coal, and A n is the coal blend ratio.

[0050] Coke oven operation is carried out by operating multiple coke ovens. Therefore, by focusing on F(T) of each coke oven, the operating time of each coke oven is adjusted so that the amount of sulfur-based gas generated is distributed over time. This makes it possible to prevent high-concentration sulfur-containing gases from locally flowing into the desulfurization equipment attached downstream of each coke oven, thereby stabilizing the operation of the coke ovens.

[0051] Furthermore, when actually producing coke by carbonizing coal, the results of this estimation method can be used to change coke production conditions such as the coal blend ratio. The estimation results can also be used to select coal suitable for coke oven operation. [Example]

[0052] The present invention will be specifically described below with reference to examples, but the present invention is not limited to the examples described below.

[0053] Nine types of coal (Coals 1 to 9), 100 g each, were sampled according to the method described in JIS M 8811, "Coals and cokes - Sampling and sample preparation methods." Each coal was crushed and classified to 125 μm or less, and air-dried at 40°C for 4 hours. The total sulfur content (unit: mass%) of Coals 1 to 9 is shown in Table 1 below. The total sulfur content was measured using the high-temperature combustion method described in JIS M 8813 "Coals and cokes - Elemental analysis method" and converted into a mass value per 1 g of coal.

[0054] [Table 1]

[0055] For Coals 1 to 9 shown in Table 1 above, the amount of sulfur-based gases generated when the coals were heated was quantified using the apparatus 1 explained based on FIG. More specifically, the amount of each gas component (hydrogen sulfide, carbonyl sulfide, sulfur dioxide, carbon disulfide, and thiophene) generated was determined for each heating temperature range at 50°C intervals in the range of 300 to 700°C.

[0056] A cryotrap was used as the cooling unit 5. A pyrolizer was used as the gas injection unit 6 and the pyrolysis furnace 8. Five mg of each coal was sampled and charged into the pyrolysis furnace 8. The atmosphere inside the pyrolysis furnace 8 was a He gas atmosphere as a carrier gas. He gas was introduced from the pyrolysis furnace 8 into the gas injection section 6, the separation column 3, and the mass spectrometry section 7 at a flow rate of 1 L / min and a split ratio of 1:50.

[0057] First, the amounts of each gas component were determined in the heating temperature range of 300 to 350°C.

[0058] First, the coal charged into the pyrolysis furnace 8 was heated for 10 minutes at a preheating temperature of 295°C. As a result, the adhering moisture and the gas generated in the heating temperature range of 295°C or less were discharged through the split path (or a path passing through the separation column 3) (preheating step). Thereafter, the coal was moved to a sheltered location in the pyrolysis furnace 8, and the temperature inside the pyrolysis furnace 8 was then raised to 300°C.

[0059] Next, the heating unit 4 was operated to raise the temperature inside the chamber 2 (i.e., the temperature of the non-cooled part of the separation column 3) to 40°C, while the cooling unit 5 (cryotrap) was operated to cool the cooled part of the separation column 3 to -180°C. In this state, the coal was returned to the pyrolysis furnace 8, and the temperature inside the furnace was increased at 3°C / min. After reaching 350°C, the temperature was maintained for 5 minutes. In this way, gas was generated from the coal (gas collection process). The coal was then moved to a sheltered location in the pyrolysis furnace 8.

[0060] The gas generated from the coal was introduced into the separation column 3 from the gas injection section 6 using a carrier gas (gas introduction step), and solidified in the cooling target section of the separation column 3 cooled to -180°C (gas capture step). The separation column 3 was continuously cooled while the coal was being fed into the pyrolysis furnace 8.

[0061] Subsequently, the cooling unit 5 was turned off to release the cooling of the separation column 3 (gas release step). At the same time, the heating unit 4 was operated to increase the temperature inside the chamber 2 to 300°C at 10°C / min (temperature increase heating step). The gas that had solidified in the cooling target portion of the separation column 3 volatilized and was transported by the carrier gas in ascending order of boiling point to reach the mass analysis section 7. The gas that reached the mass analysis section 7 was separated according to its mass-to-charge ratio, and its components were identified (analysis step).

[0062] Mass spectra of single peaks were obtained at the respective mass-to-charge ratios for hydrogen sulfide (H2S, m / z: 34), carbonyl sulfide (COS, m / z: 60), sulfur dioxide (SO2, m / z: 64), carbon disulfide (CS2, m / z: 76), and thiophene (C4H4S, m / z: 84), which are generated during coal heating.

[0063] The peak area of each gas component was converted using a calibration curve (peak area of each gas component with known concentration obtained under the same conditions) prepared in advance, to quantify each gas component.

[0064] Next, the heating unit 4 was operated to heat the inside of the chamber 2 at 300°C for 30 minutes, thereby removing hydrocarbons remaining inside the separation column 3. Thereafter, the inside of the chamber 2 was cooled to 40°C.

[0065] Subsequently, the amounts of each gas component were determined in the heating temperature range of 350 to 400°C. First, with the temperature inside chamber 2 at 40°C, cooling unit 5 was operated to cool the cooling target portion of separation column 3 to -180°C. The coal that had been moved to a sheltered location in pyrolysis furnace 8 was introduced into pyrolysis furnace 8, which had been set to 350°C, the upper limit of the previous heating temperature range (300 to 350°C), and heated for 5 minutes (preheating step). Next, the temperature inside the pyrolysis furnace 8 was increased at a rate of 3°C / min, and after reaching 400°C, it was maintained at that temperature for 5 minutes. In this way, gas was generated from the coal (gas collection step). Thereafter, the coal was moved to a sheltered location in the pyrolysis furnace 8. The subsequent steps were carried out in the same manner as in the previous steps in the heating temperature range of 350 to 400°C, and the amounts of each gas component were determined.

[0066] In this way, the heating temperature range was shifted in 50°C intervals, and the amounts of each gas component were determined within the range of 300 to 700°C.

[0067] Based on the quantitative results obtained, the amounts of each gas component generated during heating of Coals 1 to 9 were organized for each heating temperature range. Typically, the results for hydrogen sulfide (H2S) are shown in Table 2 below and in the graph of Figure 2, and the results for sulfur dioxide (SO2) are shown in Table 3 below and in the graph of Figure 3.

[0068] [Table 2]

[0069] [Table 3]

[0070] The general shape of the graph varies depending on the brand of coal, but the following are some of the major trends: With regard to hydrogen sulfide (H2S), most coals had peaks in emissions both at the low and high end of the 500°C boundary (see Table 2 and Figure 2). For sulfur dioxide (SO2), two peaks appeared, one at a lower temperature and one at a higher temperature, with the boundary being around 550°C. Coal 4, coal 6, and coal 8 showed a particularly strong peak around 450°C (see Table 3 and Figure 3).

[0071] As described above, it was found that the amount of sulfur-based gases generated during coal heating varies greatly depending on the heating temperature. This is thought to be due to differences in the form of sulfur present in coal. The sulfur-based gases generated during coal heating occur at various temperatures depending on the form of sulfur present in the coal. For example, the sulfur dioxide peak seen around 500°C is thought to be caused by the decomposition of sulfur sulfate. From these results, it can be predicted that the amount of sulfur-based gases generated during coal carbonization to produce coke will vary depending on the temperature during coal carbonization.

[0072] As described above, the amount of sulfur-containing gases generated can be organized for each coal brand and each temperature range. This allows the coal blending ratio to be set in advance so that a large amount of sulfur-containing gases is not generated at a certain temperature, which is expected to contribute to stable coke production. [Explanation of symbols]

[0073] 1: Apparatus used to quantify gases evolved from coal 2: Chamber 3: Separation column 4: Heating section 5: Cooling section 6: Gas injection section 7:Mass spectrometry section 8:Pyrolysis furnace

Claims

1. a gas collection step of collecting gas generated when coal is heated; a gas introducing step of introducing the gas collected in the gas collecting step into a separation column of a gas chromatograph; a gas capturing step of capturing the gas introduced into the separation column by cooling the separation column; a gas releasing step of releasing the gas trapped in the gas trapping step by removing the cooling of the separation column; an analyzing step of analyzing and quantifying the gas released in the gas releasing step by a mass spectrometry unit; Equipped with A method for quantifying gases generated from coal, wherein the gases include sulfur-based gases.

2. The method for quantifying gas generated from coal according to claim 1 , further comprising a heating step of heating the separation column after the cooling is removed.

3. A method for estimating the amount of gas generated during coal carbonization, which estimates the generation temperature or temperature range and generation amount of sulfur-based gas generated during coal carbonization based on the quantitative results obtained by the quantitative method described in claim 1 or 2.

4. A method for producing coke by carbonizing coal, comprising: A coke production method, comprising changing coke production conditions based on an estimation result obtained by the estimation method according to claim 3.

5. The method for producing coke according to claim 4 , wherein the production condition is a coal blending ratio.

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