Calorometer

Abstract

To provide a calorimeter capable of accurately measuring the calorific value of a fuel gas containing hydrogen.SOLUTION: A calorimeter 100 for measuring the calorific value of a fuel gas containing hydrogen is provided, comprising a catalyst 122 for combusting hydrogen at room temperature, a thermocouple 121 for measuring rising temperature of hydrogen caused by the combustion at normal temperature with the catalyst 122, a catalyst 132 for combusting a combustible gas other than hydrogen contained in the fuel gas, a heater 134 for heating the catalyst 132, and a thermocouple 131 for measuring rising temperature of the combustible gas caused by combustion with the catalyst 132 while being heated.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a calorimeter. [Background technology]

[0002] A known calorimeter used to measure the calorific value of fuel gas is one in which a thermocouple and a catalyst are provided in a fuel gas passage, and the thermocouple measures the amount of heat generated by catalytic combustion of the fuel gas passing through the passage (see, for example, Patent Document 1). In the calorimeter described in Patent Document 1, a nichrome wire for a heater is wound around the catalyst, and the fuel gas, such as methane (CH4), is heated to its combustion temperature. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 60-44855 Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors of the present application have confirmed through experiments that when a conventional calorimeter such as that described in Patent Document 1 is used to measure the calorific value of fuel gas containing hydrogen (H), measurement errors occur due to the difference in combustion temperature between hydrogen and combustible gases other than hydrogen, such as methane.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide a calorimeter that can measure the calorific value of fuel gas containing hydrogen with high accuracy. [Means for solving the problem]

[0006] The calorimeter of the present invention is a calorimeter that measures the calorific value of a fuel gas containing hydrogen, and includes a first catalyst for burning the hydrogen at room temperature, a first temperature measuring element that measures the temperature rise of the hydrogen due to combustion at room temperature in the first catalyst, a second catalyst for burning combustible gases other than the hydrogen contained in the fuel gas under heating, a heating unit that heats the second catalyst, and a second temperature measuring element that measures the temperature rise of the combustible gas due to combustion under heating in the second catalyst. [Effects of the Invention]

[0007] According to the calorimeter of the present invention, the heat quantity of fuel gas containing hydrogen can be measured with high accuracy by measuring the temperature rise of hydrogen due to combustion at room temperature in the first catalyst with the first temperature measuring element, and measuring the temperature rise of combustible gases other than hydrogen due to combustion under heating in the second catalyst with the second temperature measuring element. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing an outline of a measurement system including a calorimeter according to one embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view showing the configuration of the calorimeter shown in FIG. [Figure 3] FIG. 3 is a cross-sectional view showing the configuration of a calorimeter according to a comparative example. [Figure 4] FIG. 4 is a graph showing the results of measuring the calorific value Q′ [J] and the temperature rise ΔT [° C.] of the test gases No. 11 to No. 15 using a calorimeter according to a comparative example. [Figure 5] FIG. 5 is a graph showing the results of measuring the calorific value per unit volume Q [MJ / Nm3] of test gases No. 16 to No. 18 using a calorimeter according to a comparative example. [Figure 6] FIG. 6 is a table and graph showing the results of confirming the correlation between the concentrations of hydrogen and methane and the temperature rises ΔTH [°C] and ΔTE [°C] due to combustion when test gases No. 1 to No. 4 were continuously supplied to the calorimeter according to this embodiment. [Figure 7]FIG. 7 is a table and graph showing the results of confirming the correlation between the concentrations of hydrogen and methane and the temperature rises ΔTH [°C] and ΔTE [°C] due to combustion when test gases No. 1 to No. 4 were intermittently supplied to the calorimeter according to this embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing the configuration of a calorimeter according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described below in accordance with preferred embodiments. Note that the present invention is not limited to the embodiments described below and can be modified as appropriate without departing from the spirit of the present invention. In addition, in the embodiments described below, some components are omitted from illustration and description, but for the details of the omitted technologies, publicly known or well-known technologies are applied as appropriate within the scope of the content described below.

[0010] 1 is a block diagram showing an outline of a measurement system 1 including a calorimeter 100 according to one embodiment of the present invention. As shown in this figure, the measurement system 1 includes a gas mixing device 10 and the calorimeter 100. The gas mixing device 10 mixes a combustible gas with air and supplies the mixed gas as a fuel gas to the calorimeter 100. The calorimeter 100 combusts the fuel gas supplied from the gas mixing device 10 and measures the calorific value.

[0011] The gas mixing device 10 includes a first pipe 11, a second pipe 12, a third pipe 13, a first flow meter 14A, a second flow meter 14B, a first valve 15A, a second valve 15B, a mixer 16, a first regulator R1, and a second regulator R2.

[0012] The first pipe 11 connects the first regulator R1 and the mixer 16, and guides the flammable gas supplied through the first regulator R1 to the mixer 16. The first flow meter 14A is provided in the first pipe 11 and measures the flow rate of the flammable gas flowing through the first pipe 11. The first valve 15A is provided in the first pipe 11 downstream of the first flow meter 14A and is a flow rate adjustment valve such as a needle valve that adjusts the flow rate of the flammable gas supplied to the mixer 16.

[0013] The second pipe 12 connects the second regulator R2 and the mixer 16, and guides the air supplied through the second regulator R2 to the mixer 16. The second flow meter 14B is provided in the second pipe 12 and measures the flow rate of the air flowing through the second pipe 12. The second valve 15B is provided in the second pipe 12 downstream of the second flow meter 14B and is a flow rate adjustment valve such as a needle valve that adjusts the flow rate of the air supplied to the mixer 16.

[0014] The mixer 16 mixes the combustible gas supplied from the first pipe 11 with the air supplied from the second pipe 12. The mixer 16 is connected to a third pipe 13. The third pipe 13 supplies the mixed gas mixed in the mixer 16 to the calorimeter 100 as a fuel gas.

[0015] The calorimeter 100 includes a combustion temperature measuring unit 110, a constant voltage source (voltage source) 102, a data logger 103, and a computing device 104. Fuel gas is supplied to the combustion temperature measuring unit 110 from a third pipe 13. The constant voltage source 102 supplies power to the combustion temperature measuring unit 110. The combustion temperature measuring unit 110 is driven by the power supplied from the constant voltage source 102, and combusts the fuel gas supplied from the third pipe 13 to measure the temperature rise of the fuel gas due to combustion.

[0016] Figure 2 is a cross-sectional view showing the configuration of the calorimeter 100 shown in Figure 1. The calorimeter 100 shown in this figure includes a first combustion temperature measuring unit 120 and a second combustion temperature measuring unit 130, and is capable of measuring the calorific value of fuel gas containing hydrogen.

[0017] The first combustion temperature measuring unit 120 burns hydrogen contained in the fuel gas at room temperature and measures the temperature rise ΔT of the hydrogen due to the combustion. H On the other hand, the second combustion temperature measuring unit 130 measures the temperature rise ΔT E Measure [℃].

[0018] The combustion temperature measuring unit 110 includes a pipe 111. The pipe 111 is arranged vertically, and the third pipe 13 is connected to the upper end of the pipe 111. The pipe 111 has heat resistance to the temperature during combustion of the fuel gas and low thermal conductivity that suppresses heat radiation from the fuel gas to the outside of the pipe 111 during combustion. The pipe 111 in this embodiment is a cylindrical ceramic tube with an inner diameter of 4 mm. The inner diameter of the pipe 111 is preferably 2 mm or more and 10 mm or less. The pipe 111 may also be a stainless steel tube.

[0019] The pipe material 111 is provided with a first combustion temperature measuring section 120 and a second combustion temperature measuring section 130. The first combustion temperature measuring section 120 and the second combustion temperature measuring section 130 are arranged in series in the flow direction of the fuel gas in the order of the first combustion temperature measuring section 120 and the second combustion temperature measuring section 130. Therefore, the fuel gas supplied to the pipe material 111 from the third pipe 13 first passes through the first combustion temperature measuring section 120. At this time, the hydrogen contained in the fuel gas is burned at room temperature, and the temperature rise ΔT of the hydrogen due to the combustion H Then, the fuel gas that has passed through the first combustion temperature measuring unit 120 passes through the second combustion temperature measuring unit 130. At this time, combustible gases other than hydrogen, such as methane, contained in the fuel gas are burned under heat, and the temperature rise ΔT E [°C] is measured.

[0020] The first combustion temperature measuring unit 120 includes a thermocouple 121, a catalyst 122, and a stopper member 123. The thermocouple 121 includes a thermocouple wire 121A and a sheath 121B, and measures temperature using the Seebeck effect. The thermocouple wire 121A has a temperature measuring junction P at one end (the upper end in the figure). The sheath 121B is a hard, thin tube that maintains a highly linear shape and covers the thermocouple wire 121A. In this embodiment, the sheath 121B is a metal tube with an outer diameter of 0.5 mm. The sheath 121B is filled with an insulator. One end of a compensation lead wire (not shown) is connected to the other end (the lower end in the figure) of the thermocouple wire 121A. The compensation lead wire is drawn out from the middle of the tube 111 and connected to the data logger 103. Here, a hole through which the compensation lead wire is inserted and an airtight seal portion that closes the gap between the hole and the compensation lead wire are formed in the middle portion of the pipe material 111 (both not shown). Note that although the thermocouple 121 in this embodiment is an ungrounded type, the thermocouple 121 may be changed to a grounded type or an exposed type.

[0021] The catalyst 122 is a granular catalyst filled in the combustion chamber of the first combustion temperature measuring unit 120. The particle size of the catalyst 122 is several tens to several hundreds of times larger than the particle size of powder. From the viewpoint that it is difficult to size the catalyst 122 by sieving to a size less than 100 μm, and that if the particle size is larger than 1000 μm, the particle size becomes close to the inner diameter of the pipe material 111 and contact with hydrogen becomes poor, the particle size is preferably 100 μm to 1000 μm, and more preferably 355 μm to 420 μm. Furthermore, the catalyst 122 is capable of burning hydrogen at normal temperature (room temperature), and an example of the catalyst 122 is a metal oxide-supported platinum catalyst such as an alumina-supported platinum catalyst (Pt—Al2O3). It is known that when 1000 ppm of hydrogen is burned using a catalyst in which 0.2 mass % of platinum is supported on an alumina carrier (0.2% Pt-Al2O3 catalyst), the combustion initiation temperature is room temperature (Sadamori, Hiroki, "Special Feature on Special Combustion Technology: Current Status of Catalytic Combustion Technology, Focusing on Catalytic Combustion Burners," Journal of the Fuel Association, Vol. 58, No. 626 (1979), published in June 1979, pp. 422-423).

[0022] The mass and filling height of catalyst 122 filled in the combustion chamber of first combustion temperature measuring unit 120 may be set appropriately so that temperature measurement junction P is exposed from catalyst 122, for example, 0.075 g and approximately 3 mm when the inner diameter of pipe material 111 is 4 mm. Note that it is not essential that temperature measurement junction P is exposed from catalyst 122, and catalyst 122 may be filled in the combustion chamber of first combustion temperature measuring unit 120 so as to cover temperature measurement junction P.

[0023] A catalyst layer 121S is formed on the surface of one end side (the upper end side in the figure) of the sheath 121B so as to cover the temperature measurement contact P. This catalyst layer 121S is a coating made of a catalyst that burns hydrogen at room temperature, such as an alumina-supported platinum catalyst. One example of a method for forming the catalyst layer 121S is to apply a liquid catalyst, which is a mixture of a powdered catalyst and distilled water, to the sheath 121B and then dry it.

[0024] The length of catalyst layer 121S from one end (tip) of sheath 121B is, for example, about 1 mm, and catalyst layer 121S covers a range of about 1 mm from one end of sheath 121B, including the position of temperature measurement junction P. Most or all of catalyst layer 121S is exposed from catalyst 122. Note that it is not essential that catalyst layer 121S be exposed from catalyst 122, and catalyst layer 121S may be arranged so as to be covered by catalyst 122. Furthermore, it is not essential to provide catalyst layer 121S.

[0025] The stopper member 123 is disposed below the combustion chamber of the first combustion temperature measuring unit 120. The stopper member 123 is a metal plate, such as stainless steel, fitted to the inner circumferential surface of the pipe material 111, and has a plurality of vent holes (not shown) formed therein. The diameter of the vent holes is smaller than the particle diameter (average value) of the catalyst 122. As a result, the fuel gas passes through the vent holes, but the catalyst 122 does not pass through the vent holes and accumulates on the stopper member 123. The stopper member 123 of this embodiment is a circular plate. The thickness of the stopper member 123 of this embodiment is approximately 1 mm. The diameter of the vent holes of the stopper member 123 of this embodiment is 0.3 mm. The stopper member 123 may be made of glass wool.

[0026] The second combustion temperature measuring unit 130 includes a thermocouple 131, a catalyst 132, a stopper member 133, and a heater 134. The thermocouple 131 has a configuration similar to that of the thermocouple 121, including a thermocouple wire 131A and a sheath 131B, and measures temperature using the Seebeck effect. The thermocouple wire 131A has a temperature measuring junction P at one end (the upper end in the figure). One end of a compensation wire (not shown) is connected to the other end (the lower end in the figure) of the thermocouple wire 131A. The compensation wire is drawn out from the downstream end (the lower end in the figure) of the tubular member 111 and connected to the data logger 103. The downstream end of the tubular member 111 is formed with a hole through which the compensation wire is inserted and an airtight seal that seals the gap between the hole and the compensation wire (both not shown). The downstream end of the tubular member 111 is also formed with an exhaust hole (not shown). Although the thermocouple 131 in this embodiment is an ungrounded type, the thermocouple 131 may be changed to a grounded type or an exposed type.

[0027] The catalyst 132 is a granular catalyst filled in the combustion chamber of the second combustion temperature measuring unit 130. The particle size of the catalyst 132 is several tens to several hundreds of times larger than the particle size of powder. From the viewpoint that it is difficult to size the catalyst 132 by sieving to a size less than 100 μm, and that if the particle size is larger than 1000 μm, the particle size becomes close to the inner diameter of the pipe material 111 and contact with the combustible gas is deteriorated, the particle size of the catalyst 132 is preferably 100 μm to 1000 μm, and more preferably 355 μm to 420 μm. Furthermore, the catalyst 132 is a catalyst that can burn combustible gases other than hydrogen contained in fuel gas such as methane under heat, and is, for example, a catalyst supported by a metal or metal oxide such as palladium (Pd) or platinum (Pt).

[0028] The mass and filling height of catalyst 132 filled in the combustion chamber of second combustion temperature measuring unit 130 may be set appropriately so that temperature measurement junction P is exposed from catalyst 132, for example, 0.075 g and approximately 3 mm when the inner diameter of pipe material 111 is 4 mm. Note that it is not essential that temperature measurement junction P is exposed from catalyst 132, and catalyst 132 may be filled in the combustion chamber of second combustion temperature measuring unit 130 so as to cover temperature measurement junction P.

[0029] A catalyst layer 131S is formed on the surface of one end side (upper end side in the figure) of the sheath 131B so as to cover the temperature measuring contact P. This catalyst layer 131S may be a coating made of a catalyst such as palladium or platinum. One example of a method for forming this catalyst layer 131S is to apply a liquid catalyst, which is a mixture of powdered catalyst and distilled water, to the sheath 131B and then dry it.

[0030] The length of this catalyst layer 131S from one end (tip) of the sheath 131B may be, for example, about 1 mm, and it may be arranged to cover a range of about 1 mm from one end of the sheath 131B including the position of the temperature measuring junction P. Most or all of this catalyst layer 131S may be exposed from the catalyst 132, or this catalyst layer 131S may be covered by the catalyst 132. Note that it is not essential to provide the catalyst layer 131S.

[0031] The stopper member 133 is disposed below the combustion chamber of the second combustion temperature measuring unit 130. The stopper member 133 is a metal plate, such as stainless steel, fitted to the inner circumferential surface of the pipe material 111, and has a plurality of vent holes (not shown) formed therein. The diameter of the vent holes is smaller than the particle diameter (average value) of the catalyst 132. As a result, the fuel gas passes through the vent holes, but the catalyst 132 does not pass through the vent holes and accumulates on the stopper member 133. The stopper member 133 of this embodiment is a circular plate. The thickness of the stopper member 133 of this embodiment is approximately 1 mm. The diameter of the vent holes of the stopper member 133 of this embodiment is 0.3 mm. The stopper member 133 may be made of glass wool.

[0032] The heater 134 is a coil-type heater through which the tubular material 111 is inserted. The coil portion 134A of this heater 134 is wound around an area that includes at least the combustion chamber of the second combustion temperature measuring unit 130 of the tubular material 111. The coil portion 134A is connected to the constant voltage source 102 via the lead portion 134B, and generates heat when a voltage is applied from the constant voltage source 102. When the coil portion 134A generates heat by applying a voltage from the constant voltage source 102, the catalyst 132 is heated to a predetermined temperature. Note that the coil portion 134A is disposed away from the combustion chamber of the first combustion temperature measuring unit 120 of the tubular material 111, and the catalyst 122 of the first combustion temperature measuring unit 120 is not heated by the heater 134 and is maintained at room temperature.

[0033] The combustion temperature measuring unit 110 is housed in a protective container (not shown). This protective container prevents fluctuations in the temperatures measured by the thermocouples 121 and 131 due to, for example, the influence of wind. The protective container is provided with an exhaust hole for discharging exhaust gas generated by the combustion of the fuel gas to the outside of the protective container.

[0034] The data logger 103 measures the temperature rise ΔT due to the combustion of hydrogen in the catalyst 122 and catalyst layer 121S of the first combustion temperature measuring unit 120 based on the signal output from the thermocouple 121. H The data logger 103 also records the signal output from the thermocouple 131, that is, the temperature rise ΔT due to the combustion of the combustible gas other than hydrogen in the catalyst 132 of the second combustion temperature measuring unit 130. E Record the temperature in degrees Celsius.

[0035] The arithmetic device 104 calculates the calorific value during combustion of the fuel gas supplied to the combustion temperature measuring unit 110 based on the recorded contents of the data logger 103. When calculating the calorific value, the measured values ​​of the first flow meter 14A and the second flow meter 14B (see FIG. 1) are also input to the arithmetic device 104. A PC (Personal Computer), for example, can be used as the arithmetic device 104.

[0036] In the calorimeter 100 configured as described above, the calculation device 104 calculates the temperature rise ΔT measured by the thermocouples 121 and 131 and recorded in the data logger 103. H [℃],ΔT E The calorific value of the fuel gas during combustion is calculated based on the temperature change [°C]. The calculation device 104 stores correlation data that indicates the correlation between the change in the temperature measured by the thermocouples 121 and 131 and the calorific value of the fuel gas during combustion, and the calculation device 104 uses this correlation data to calculate the calorific value of the fuel gas during combustion.

[0037] Specifically, a control device (not shown) controls the first valve 15A, the second valve 15B, and the mixer 16 shown in FIG. 1 to cause the flammable gas to flow through the first pipe 11 and the air to flow through the second pipe 12, and the flammable gas and the air are mixed in the mixer 16. This generates fuel gas containing a predetermined concentration of flammable gas. This fuel gas is supplied to the calorimeter 100 through the third pipe 13. At this time, the first flow meter 14A measures the flow rate of the flammable gas flowing through the first pipe 11 and outputs the measurement information to the calculation device 104, and the second flow meter 14B measures the flow rate of the air flowing through the second pipe 12 and outputs the measurement information to the calculation device 104.

[0038] Constant voltage source 102 applies a voltage to heater 134, and the base temperature of thermocouple 131 of second combustion temperature measuring unit 130 becomes, for example, approximately 250 to 400°C. In this state, the temperature around temperature measuring junction P of thermocouple 131 rises due to heat generated during combustion of combustible gases other than hydrogen contained in the fuel gas. Thermocouple 131 transmits a signal corresponding to the temperature around temperature measuring junction P to data logger 103, and data logger 103 stores this signal.

[0039] On the other hand, the base temperature of thermocouple 121 of first combustion temperature measuring unit 120 is room temperature. In this state, the heat generated during combustion of hydrogen contained in the fuel gas increases the temperature around temperature measuring junction P of thermocouple 121. Thermocouple 121 transmits a signal corresponding to the temperature around temperature measuring junction P to data logger 103, and data logger 103 stores this signal.

[0040] The calculation device 104 calculates the calorific value of the fuel gas during combustion from the correlation data stored in advance, the temperature measurement information of the thermocouples 121 and 131 stored in the data logger 103, and the flow rate information of the first flow meter 14A and the second flow meter 14B. Here, the calculation device 104 calculates the calorific value of the fuel gas during combustion from the temperature rise ΔT H [°C] and the flow rate information of the first flow meter 14A and the second flow meter 14B, the amount of heat Q H The calculation device 104 also calculates the temperature rise ΔT due to the combustion of the combustible gas other than hydrogen, which is output from the thermocouple 131 and stored in the data logger 103. E [°C] and the flow rate information of the first flow meter 14A and the second flow meter 14B, the amount of heat Q E Then, the calculation device 104 calculates the amount of heat Q H and heat Q E and sum up.

[0041] The following describes an experiment conducted to confirm the accuracy of calorific value measurement by the calorimeter 100 according to this embodiment. In this experiment, calorific value measurement of a test gas was performed using the calorimeter 100C according to a comparative example, and calorific value measurement of a test gas was performed using the calorimeter 100 according to this embodiment.

[0042] 3 is a cross-sectional view showing the configuration of a calorimeter 100C according to a comparative example. As shown in this figure, the combustion temperature measuring unit 110C of the calorimeter 100C according to the comparative example does not include the first combustion temperature measuring unit 120 (see FIG. 2), but includes the second combustion temperature measuring unit 130. That is, in the combustion temperature measuring unit 110C of the comparative example, the combustion of hydrogen at room temperature and the temperature rise ΔT H Instead, the test gas is burned at a relatively high temperature (330°C in this experiment) and the temperature rise ΔT [°C] of the test gas due to that combustion is measured.

[0043] Five types of test gases No. 1 to No. 5 below were supplied to the combustion temperature measuring section 110C of the calorimeter 100C according to this comparative example, and the calorific value Q' [J] and temperature rise ΔT [° C.] due to the combustion of the test gases were measured. No. 11: Calorific value per unit volume = 32 MJ / Nm3 , H2=0%, CH4=100% No. 12: Calorific value per unit volume = 36 MJ / Nm 3 , H2=0%, CH4=100% No. 13: Calorific value per unit volume = 40MJ / Nm 3 , H2=0%, CH4=100% No. 14: Calorific value per unit volume = 43 MJ / Nm 3 , H2=0%, CH4=100% No. 15: Calorific value per unit volume = 45 MJ / Nm 3 , H2=0%, CH4=100%

[0044] 4 is a graph showing the results of measuring the calorific value Q' [J] and the temperature rise ΔT [°C] of the test gases No. 11 to No. 15 using the calorimeter 100C according to the comparative example. As shown in this graph, the coefficient of determination R 2 = 0.998, and the maximum measurement error in temperature rise ΔT [°C] was 0.43%. From the above, it was confirmed that when the fuel gas does not contain hydrogen, the calorific value Q' [J] and temperature rise ΔT [°C] can be measured with high accuracy.

[0045] The following three types of test gases No. 16 to No. 18 were supplied to the combustion temperature measuring section 110C of the calorimeter 100C according to the comparative example, and the calorific value Q [MJ / Nm 3 ] was measured. No. 16: Calorific value per unit volume = 34.5 MJ / Nm 3 , H2=20%, CH4=80% No. 17: Calorific value per unit volume = 37 MJ / Nm 3 , H2=10%, CH4=90% No. 18: Calorific value per unit volume = 45MJ / Nm 3 , H2=20%, CH4=80%

[0046] FIG. 5 shows the calorific values ​​Q [MJ / Nm 3]. As shown in this graph, the calorific value per unit volume of the test gas Q [MJ / Nm 3 ], there was a maximum measurement error of 10.0% between the true value and the calculated value. Specifically, the calorific value per unit volume Q [MJ / Nm 3 ] was underestimated by an error of 10.0%. Also, the calorific value per unit volume Q [MJ / Nm 3 ] was underestimated by an error of 4.3%. Furthermore, the calorific value per unit volume Q [MJ / Nm 3 ] was underestimated by an error of 8.4%.

[0047] The following four types of test gases, No. 1 to No. 4, were continuously supplied to the calorimeter 100 according to this embodiment to measure the concentrations of hydrogen and methane and the temperature rise ΔT due to combustion. H [℃],ΔT E In this experiment, a test gas at a flow rate of 3 mL / min and air at a flow rate of 97 mL / min were continuously supplied to the calorimeter 100, and the temperature rise ΔT H [°C] and the temperature rise ΔT measured by the second combustion temperature measuring unit 130 E The temperature [°C] was measured continuously. No.1: Calorific value per unit volume = 39.9 MJ / Nm 3 , H2=0%, CH4=100% No. 2: Calorific value per unit volume = 34.7 MJ / Nm 3 , H2=19.2%, CH4=80.8% No. 3: Calorific value per unit volume = 26.3 MJ / Nm 3 , H2=50%, CH4=50% No. 4: Calorific value per unit volume = 12.8 MJ / Nm 3 , H2=100%, CH4=0%

[0048] FIG. 6 shows the relationship between the concentrations of hydrogen and methane and the temperature rise ΔT due to combustion when test gases No. 1 to No. 4 are continuously supplied to the calorimeter 100 according to this embodiment.H [℃],ΔT E 10 is a table and a graph showing the results of checking the correlation between the hydrogen concentration and the temperature rise ΔT measured by the first combustion temperature measuring unit 120. H [°C] increases, and the temperature rise ΔT measured by the second combustion temperature measuring unit 130 E On the other hand, it was confirmed that the higher the methane concentration, the lower the temperature rise ΔT measured by the second combustion temperature measuring unit 130. E [°C] increases, and the temperature rise ΔT measured by the first combustion temperature measuring unit 120 H It was confirmed that the temperature [℃] was lower.

[0049] An experiment was conducted to confirm the correlation between the concentrations of hydrogen and methane and the temperature rise ΔT [°C] due to combustion by intermittently supplying the test gases No. 1 to No. 4 described above to the calorimeter 100 according to this embodiment. In this experiment, air was continuously supplied to the calorimeter 100 at a flow rate of 85 mL / min, while a fuel gas with a volume of 0.36 mL was intermittently supplied to the calorimeter 100. The temperature rise ΔT H [°C] and the temperature rise ΔT measured by the second combustion temperature measuring unit 130 E Measurement of the temperature [°C] was performed intermittently.

[0050] FIG. 7 shows the concentration of hydrogen and methane and the temperature rise ΔT due to combustion when test gases No. 1 to No. 4 are intermittently supplied to the calorimeter 100 according to this embodiment. H [℃],ΔT E 10 is a table and a graph showing the results of checking the correlation between the hydrogen concentration and the temperature rise ΔT measured by the first combustion temperature measuring unit 120. H [°C] increases, and the temperature rise ΔT measured by the second combustion temperature measuring unit 130 E On the other hand, it was confirmed that the higher the methane concentration, the lower the temperature rise ΔT measured by the second combustion temperature measuring unit 130. E [°C] increases, and the temperature rise ΔT measured by the first combustion temperature measuring unit 120 H It was confirmed that the temperature [℃] was lower.

[0051] As described above, the combustion temperature measuring unit 110 of the calorimeter 100 according to this embodiment burns hydrogen contained in fuel gas at room temperature and measures the temperature rise ΔT H The first combustion temperature measuring unit 120 measures the temperature rise ΔT [°C] by burning the combustible gas other than hydrogen contained in the fuel gas under heating. E [°C]. This allows the calorific value of the fuel gas containing hydrogen to be calculated based on the temperature rise ΔT H [℃] and the temperature rise ΔT due to the combustion of flammable gases other than hydrogen, such as methane E Therefore, it is possible to suppress a decrease in accuracy in calorific value measurement of fuel gas due to the inclusion of hydrogen in the fuel gas, and to achieve high accuracy in calorific value measurement of fuel gas containing hydrogen.

[0052] In the calorimeter 100 according to this embodiment, the calculation device 104 calculates the temperature rise ΔT due to the combustion of hydrogen measured by the thermocouple 121 of the first combustion temperature measuring unit 120. H [℃] based on the amount of heat Q H and calculate the temperature rise ΔT due to the combustion of the combustible gas other than hydrogen measured by the second combustion temperature measuring unit 130. E [℃] based on the amount of heat Q E Calculate the total amount of heat (Q H +Q E ) [°C]. This allows the calorific value of the fuel gas containing hydrogen to be calculated as the temperature rise ΔT H [℃],ΔT E It is possible to perform highly accurate calculations based on [°C].

[0053] Furthermore, in the calorimeter 100 according to this embodiment, the catalyst 122 of the first combustion temperature measuring unit 120 and the catalyst 132 of the second combustion temperature measuring unit 130 are housed in the tubular member 111 so that the fuel gas passes through the catalyst 122 of the first combustion temperature measuring unit 120, and the fuel gas that has passed through this catalyst 122 passes through the catalyst 132 of the second combustion temperature measuring unit 130. That is, in the calorimeter 100 according to this embodiment, the first combustion temperature measuring unit 120 and the second combustion temperature measuring unit 130 are connected in series. As a result, hydrogen contained in the fuel gas burns at room temperature in the first combustion temperature measuring unit 120, and flammable gases other than hydrogen contained in the fuel gas burn under heating in the second combustion temperature measuring unit 130. That is, the hydrogen contained in the fuel gas and flammable gases other than hydrogen always pass through the combustion section in the tubular member 111. This prevents the hydrogen contained in the fuel gas and flammable gases other than hydrogen from being exhausted from the tubular member 111 without being combusted.

[0054] 8 is a cross-sectional view showing the configuration of a calorimeter 200 according to another embodiment of the present invention. As shown in this figure, calorimeter 200 according to this embodiment includes a combustion temperature measuring unit 210 in which a first combustion temperature measuring unit 120 and a second combustion temperature measuring unit 130 are arranged in parallel. This combustion temperature measuring unit 210 includes a first tubular member 211 and a second tubular member 212.

[0055] The third pipe 13 is connected to one end of the first pipe 211. Furthermore, the fourth pipe 14 branching from the third pipe 13 is connected to one end of the second pipe 212. The first pipe 211 and the second pipe 212 are pipes that have heat resistance to the temperature during combustion of the fuel gas and low heat conductivity that suppresses heat radiation of the fuel gas to the outside of the pipe during combustion. In this embodiment, the first pipe 211 and the second pipe 212 are cylindrical ceramic tubes with an inner diameter of 4 mm. The inner diameter of the first pipe 211 and the second pipe 212 is preferably 2 mm or more and 10 mm or less. Furthermore, the first pipe 211 and the second pipe 212 may be stainless steel tubes.

[0056] As described above, in the combustion temperature measuring section 210 of this embodiment, the first combustion temperature measuring section 120 and the second combustion temperature measuring section 130 are arranged in parallel with the flow direction of the fuel gas. Therefore, the fuel gas supplied from the third pipe 13 to the first pipe 211 passes through the first combustion temperature measuring section 120. At this time, the hydrogen contained in the fuel gas is burned at room temperature, and the temperature rise ΔT of the hydrogen due to the combustion H On the other hand, the fuel gas supplied from the fourth pipe 14 to the second pipe 212 passes through the second combustion temperature measuring section 130. At this time, combustible gases other than hydrogen, such as methane, contained in the fuel gas are burned under heating, and the temperature rise ΔT E [°C] is measured.

[0057] In the calorimeter 200 configured as above, the calculation device 104 calculates the temperature rise ΔT due to the combustion of hydrogen, which is output from the thermocouple 121 and stored in the data logger 103. H [°C] and the flow rate information of the first flow meter 14A and the second flow meter 14B, the amount of heat Q H In addition, the temperature rise ΔT due to the combustion of the combustible gas other than hydrogen, which is output from the thermocouple 131 and stored in the data logger 103, is calculated. E [°C] and the flow rate information of the first flow meter 14A and the second flow meter 14B, the amount of heat Q E Then, the calculation device 104 calculates the calculated heat quantity Q H and heat Q E and sum up.

[0058] The present invention has been described above based on the above embodiment, but the present invention is not limited to the above embodiment, and modifications may be made within the scope of the spirit of the present invention, and publicly known or well-known technologies may be combined as appropriate.

[0059] For example, in the above embodiment, the catalysts 122, 132 are granular, but the catalysts 122, 132 may be powdered. Also, the pipe material 111, the first pipe material 211, and the second pipe material 212 are oriented vertically, but the pipe material 111, the first pipe material 211, and the second pipe material 212 may be oriented horizontally. Also, the structure of the combustion temperature measuring units 110, 210 is not limited to the configuration in the above embodiment, and may be modified as appropriate.

[0060] Furthermore, in the above embodiment, the thermocouples 121 and 131 are used as temperature measuring elements, but other temperature measuring elements such as resistance temperature detectors may also be used. [Explanation of symbols]

[0061] 100 calorimeter 104 Arithmetic unit (calculation unit) 111 Piping material 121 Thermocouple (first temperature sensor) 122 Catalyst (first catalyst) 131 Thermocouple (second temperature sensor) 132 Catalyst (Second Catalyst) 134 Heater (heating part) 200 Calorimeter P Temperature measuring junction ΔT H Rising temperature ΔT E Rising temperature Q H Heat amount (first heat amount) Q E Heat amount (secondary heat amount)

Claims

1. A calorimeter for measuring the calorific value of a fuel gas containing hydrogen, a first catalyst for burning the hydrogen at room temperature; a first temperature measuring element for measuring a temperature rise of the hydrogen due to combustion at room temperature in the first catalyst; a second catalyst for burning, under heating, the combustible gas other than hydrogen contained in the fuel gas; a heating unit that heats the second catalyst; a second temperature measuring body for measuring a temperature rise of the combustible gas due to combustion under heating in the second catalyst; A calorimeter comprising:

2. 2. The calorimeter according to claim 1, further comprising a calculation unit that calculates a first calorific value based on the rising temperature of the hydrogen measured by the first temperature measuring element, calculates a second calorific value based on the rising temperature of the combustible gas measured by the second temperature measuring element, and calculates a sum of the first calorific value and the second calorific value.

3. a pipe member that houses the first catalyst, the temperature measuring junction of the first temperature measuring element, the second catalyst, and the temperature measuring junction of the second temperature measuring element and into which the fuel gas flows; 3. The calorimeter according to claim 1, wherein the first catalyst and the second catalyst are housed in the tubing such that the fuel gas passes through the first catalyst and the fuel gas that has passed through the first catalyst passes through the second catalyst.

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