JP2023155667A - calorimeter - Google Patents

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

The present invention relates to a calorimeter.

As a calorimeter used to measure the calorific value of fuel gas, one is known that has a thermocouple and a catalyst installed in the fuel gas passage, and measures the calorific value due to catalytic combustion of the fuel gas passing through the passage. (For example, see Patent Document 1). In the calorimeter described in Patent Document 1, a nichrome wire for a heater is wound around a catalyst, and a fuel gas such as methane (CH ₄ ) is heated to a combustion temperature.

Japanese Patent Application Laid-open No. 60-44855

When using a conventional calorimeter such as that described in Patent Document 1 to measure the calorific value of fuel gas containing hydrogen (H ₂ ), the difference in combustion temperature between hydrogen and combustible gas other than hydrogen, such as methane, must be measured. It has been confirmed through experiments by the inventors of the present application that measurement errors occur as a factor.

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

The calorimeter according to the present invention is a calorimeter that measures the calorific value of fuel gas containing hydrogen, and includes a first catalyst for combusting the hydrogen at room temperature, and the hydrogen produced by combustion at room temperature in the first catalyst. a first temperature measuring element that measures the temperature increase of the fuel gas, a second catalyst that burns a combustible gas other than the hydrogen contained in the fuel gas under heating, and a heating section 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.

According to the calorimeter of the present invention, the temperature rise of hydrogen due to combustion at room temperature in the first catalyst is measured by the first temperature measuring element, and the rise in combustible gas other than hydrogen due to combustion under heating in the second catalyst is measured. By measuring the temperature with the second temperature measuring element, the amount of heat of the fuel gas containing hydrogen can be measured with high precision.

FIG. 1 is a block diagram schematically showing a measurement system including a calorimeter according to an embodiment of the present invention. FIG. 2 is a sectional view showing the configuration of the calorimeter shown in FIG. 1. FIG. 3 is a sectional view showing the configuration of a calorimeter according to a comparative example. FIG. 4 shows No. 2 using the calorimeter according to the comparative example. 11～No. 3 is a graph showing the results of measuring the calorific value Q' [J] and the temperature rise ΔT [° C.] of No. 15 test gas. FIG. 5 shows No. 1 using the calorimeter according to the comparative example. 16~No. It is a graph showing the results of measuring the calorific value Q [MJ/Nm ³ ] per unit volume of No. 18 test gases. FIG. 6 shows No. 1 in the calorimeter according to this embodiment. 1~No. 4 is a table and a graph showing the results of confirming the correlation between the concentration of hydrogen and methane and the temperature increase due to combustion ΔT _H [°C] and ΔT _E [°C] by continuously supplying the test gas of No. 4. FIG. 7 shows No. 1 in the calorimeter according to this embodiment. 1~No. 4 is a table and a graph showing the results of intermittently supplying the test gas of No. 4 and confirming the correlation between the concentration of hydrogen and methane and the temperature rise due to combustion ΔT _H [°C] and ΔT _E [°C]. FIG. 8 is a sectional view showing the configuration of a calorimeter according to another embodiment of the present invention.

Hereinafter, the present invention will be explained along with preferred embodiments. Note that the present invention is not limited to the embodiments shown below, and can be modified as appropriate without departing from the spirit of the present invention. In addition, in the embodiments described below, illustrations and explanations of some components are omitted, but the details of the omitted techniques will be described within the scope of not contradicting the content described below. Publicly known or well-known techniques are applied as appropriate.

FIG. 1 is a block diagram schematically showing a measurement system 1 including a calorimeter 100 according to an embodiment of the present invention. As shown in this figure, the measurement system 1 includes a gas mixing device 10 and a calorimeter 100. The gas mixing device 10 mixes flammable gas and air and supplies the mixed gas to the calorimeter 100 as a fuel gas. The calorimeter 100 burns the fuel gas supplied from the gas mixing device 10 and measures the calorific value.

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, It includes a mixer 16, a first regulator R1, and a second regulator R2.

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 combustible gas flowing through the first pipe 11. The first valve 15A is a flow rate adjustment valve such as a needle valve that is provided downstream of the first flowmeter 14A in the first pipe 11 and adjusts the flow rate of the combustible gas supplied to the mixer 16.

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 air flowing through the second pipe 12. The second valve 15B is a flow rate adjustment valve such as a needle valve that is provided downstream of the second flowmeter 14B in the second pipe 12 and adjusts the flow rate of air supplied to the mixer 16.

The mixer 16 mixes the flammable gas supplied from the first pipe 11 and the air supplied from the second pipe 12. A third pipe 13 is connected to this mixer 16 . This third pipe 13 supplies the mixed gas mixed in the mixer 16 to the calorimeter 100 as fuel gas.

The calorimeter 100 includes a combustion temperature measuring section 110, a constant voltage source (voltage source) 102, a data logger 103, and a calculation device 104. Fuel gas is supplied to the combustion temperature measuring section 110 from the third pipe 13. Constant voltage source 102 supplies power to combustion temperature measuring section 110 . The combustion temperature measuring section 110 is driven by electric power supplied from the constant voltage source 102, burns the fuel gas supplied from the third pipe 13, and measures the temperature rise of the fuel gas due to combustion.

FIG. 2 is a sectional view showing the configuration of the calorimeter 100 shown in FIG. 1. The calorimeter 100 shown in this figure includes a first combustion temperature measuring section 120 and a second combustion temperature measuring section 130, and is adapted to measure the calorific value of fuel gas containing hydrogen.

The first combustion temperature measurement unit 120 burns hydrogen contained in the fuel gas at room temperature and measures the temperature rise ΔT _H [° C.] of hydrogen due to the combustion. On the other hand, the second combustion temperature measurement unit 130 burns a combustible gas other than hydrogen, such as methane, contained in the fuel gas under heating, and measures the temperature increase ΔT _E [°C] of the combustible gas due to the combustion. .

The combustion temperature measuring section 110 includes a tube material 111. The tube material 111 is arranged vertically, and the third pipe 13 is connected to the upper end of the tube material 111. The pipe material 111 is a pipe material that has heat resistance against 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 material 111 during combustion. The tube material 111 of this embodiment is a cylindrical ceramic tube with an inner diameter of 4 mm. Note that the inner diameter of the tube material 111 is preferably 2 mm or more and 10 mm or less. Further, the tube material 111 may be a stainless steel tube.

The tube material 111 is provided with a first combustion temperature measurement section 120 and a second combustion temperature measurement section 130. The first combustion temperature measurement section 120 and the second combustion temperature measurement section 130 are arranged in series in the order of the first combustion temperature measurement section 120 and the second combustion temperature measurement section 130 in the flow direction of the fuel gas. Therefore, the fuel gas supplied from the third pipe 13 to the pipe material 111 first passes through the first combustion temperature measurement section 120. At this time, hydrogen contained in the fuel gas is combusted at room temperature, and the rising temperature ΔT _H [° C.] of hydrogen due to the combustion is measured. The fuel gas that has passed through the first combustion temperature measurement section 120 then passes through the second combustion temperature measurement section 130. At this time, a combustible gas other than hydrogen, such as methane, contained in the fuel gas is combusted under heating, and the temperature rise ΔT _E [° C.] of the combustible gas due to the combustion is measured.

The first combustion temperature measuring section 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 is provided with a temperature measuring junction P at one end (the upper end in the figure). The sheath 121B is a hard and thin tube material that maintains a highly linear shape, and covers the thermocouple wire 121A. The sheath 121B of this embodiment is a metal tube with an outer diameter of 0.5 mm. The inside of the sheath 121B is filled with an insulator. One end of a compensation conducting wire (not shown) is connected to the other end (lower end in the figure) of the thermocouple element wire 121A. This compensation lead wire is drawn out from the middle part of the tube 111 and connected to the data logger 103. Here, a hole through which the compensation conductor is inserted, and an airtight seal portion that closes the gap between the hole and the compensation conductor are formed in the intermediate portion of the tube member 111 (both not shown). Note that although the thermocouple 121 of this embodiment is a non-grounded type, the thermocouple 121 may be changed to a grounded type or an exposed type.

The catalyst 122 is a granular catalyst filled in the combustion chamber of the first combustion temperature measuring section 120 . The particle size of the catalyst 122 is several tens to hundreds of times larger than the particle size of the powder. The particle size of the catalyst 122 is preferably 100 μm or more and 1000 μm or less, since it is difficult to sieve and size the catalyst to less than 100 μm, and if it is larger than 1000 μm, it will become close to the inner diameter of the tube material 111, resulting in poor contact with hydrogen. , more preferably 355 μm or more and 420 μm or less. Further, the catalyst 122 is capable of burning hydrogen at normal temperature (room temperature), and includes, for example, a metal oxide supported platinum catalyst such as an alumina supported platinum catalyst (Pt-Al ₂ O ₃ ). Here, when 1000 ppm of hydrogen is combusted using a catalyst (0.2% Pt-Al ₂ O ₃ catalyst) in which 0.2% by mass of platinum is supported on an alumina carrier, the combustion start temperature is room temperature ( (Hiroki Sadamori, “Special Combustion Technology Special Feature: Current Status of Catalytic Combustion Technology, Focusing on Catalytic Combustion Barter”, Fuel Association Journal Vol. 58, No. 626 (1979), June 1979 issue) (pp. 422-423).

The mass and filling height of the catalyst 122 filled in the combustion chamber of the first combustion temperature measurement section 120 may be set appropriately so that the temperature measurement contact point P is exposed from the catalyst 122. For example, if the inner diameter of the tube material 111 is 4 mm. In this case, it is 0.075g, about 3mm, etc. Note that it is not essential that the temperature measuring contact P be exposed from the catalyst 122, and the combustion chamber of the first combustion temperature measuring section 120 may be filled with the catalyst 122 so as to cover the temperature measuring contact P.

A catalyst layer 121S is formed on the surface of one end side (upper end side in the figure) of the sheath 121B so as to cover the temperature measuring contact point P. This catalyst layer 121S is a coating film made of a catalyst that burns hydrogen at room temperature, such as an alumina-supported platinum catalyst. An 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 dry it.

The length of the catalyst layer 121S from one end (tip) of the sheath 121B is, for example, about 1 mm, and the catalyst layer 121S covers an area of about 1 mm from the one end of the sheath 121B including the position of the temperature measuring contact point P. Most or the entirety of this catalyst layer 121S is exposed from the catalyst 122. Note that it is not essential that the catalyst layer 121S be exposed from the catalyst 122, and the catalyst layer 121S may be covered with the catalyst 122. Further, it is not essential to provide the catalyst layer 121S.

The stopper member 123 is arranged below the combustion chamber of the first combustion temperature measurement section 120. This stopper member 123 is a plate made of metal such as stainless steel that fits on the inner peripheral surface of the tube member 111, and has a plurality of ventilation holes (not shown) formed therein. The diameter of this vent hole is smaller than the particle size (average value) of the catalyst 122. As a result, although the fuel gas passes through the vent, the catalyst 122 is deposited on the stopper member 123 without passing through the vent. The stopper member 123 of this embodiment is a disk. Further, the thickness of the stopper member 123 of this embodiment is approximately 1 mm. Furthermore, the diameter of the ventilation hole of the stopper member 123 of this embodiment is 0.3 mm. Note that the stopper member 123 may be made of glass wool.

The second combustion temperature measuring section 130 includes a thermocouple 131, a catalyst 132, a stopper member 133, and a heater 134. The thermocouple 131 has the same configuration as the thermocouple 121, includes a thermocouple wire 131A and a sheath 131B, and measures temperature using the Seebeck effect. The thermocouple wire 131A is provided with a temperature measuring junction P at one end (the upper end in the figure). One end of a compensating lead wire (not shown) is connected to the other end (lower end in the figure) of the thermocouple element wire 131A. This compensating lead wire is drawn out from the downstream end (lower end in the figure) of the tube 111 and is connected to the data logger 103. Here, at the downstream end of the tube material 111, a hole through which the compensation conductor is inserted and an airtight seal portion that closes the gap between the hole and the compensation conductor are formed (both not shown). Further, an exhaust hole (not shown) is formed at the downstream end of the pipe material 111. Note that although the thermocouple 131 of this embodiment is a non-grounded type, the thermocouple 131 may be changed to a grounded type or an exposed type.

The catalyst 132 is a granular catalyst filled in the combustion chamber of the second combustion temperature measuring section 130. The particle size of the catalyst 132 is several tens to hundreds of times larger than the particle size of the powder. The particle size of the catalyst 132 is 100 μm or more and 1000 μm or less, since it is difficult to sieve and size the catalyst to less than 100 μm, and if it is larger than 1000 μm, it will be close to the inner diameter of the tube material 111 and contact with flammable gas will be poor. is preferable, and more preferably 355 μm or more and 420 μm or less. Further, the catalyst 132 is a catalyst capable of burning a combustible gas other than hydrogen contained in a fuel gas such as methane under heating, and is, for example, a metal such as palladium (Pd) or platinum (Pt). These include those supported by oxides.

The mass and filling height of the catalyst 132 filled in the combustion chamber of the second combustion temperature measurement section 130 may be set appropriately so that the temperature measurement contact P is exposed from the catalyst 132. For example, if the inner diameter of the tube material 111 is 4 mm. In this case, it is 0.075g, about 3mm, etc. Note that it is not essential that the temperature measuring contact P be exposed from the catalyst 132, and the combustion chamber of the second combustion temperature measuring section 130 may be filled with the catalyst 132 so as to cover the temperature measuring contact P.

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 point P. This catalyst layer 131S may be a coating film made of a catalyst such as palladium or platinum. An example of a method for forming the catalyst layer 131S is a method in which a liquid catalyst prepared by mixing a powdered catalyst and distilled water is applied to the sheath 131B and dried.

The length of this catalyst layer 131S from one end (tip) of the sheath 131B may be approximately 1 mm, for example, and may cover an area of approximately 1 mm from one end of the sheath 131B including the position of the temperature measuring contact P. Most or all of this catalyst layer 131S may be exposed from the catalyst 132, or this catalyst layer 131S may be covered with the catalyst 132. Note that it is not essential to provide the catalyst layer 131S.

The stopper member 133 is arranged below the combustion chamber of the second combustion temperature measuring section 130. This stopper member 133 is a plate made of metal such as stainless steel that fits on the inner peripheral surface of the tube member 111, and has a plurality of ventilation holes (not shown) formed therein. The diameter of this vent hole is smaller than the particle size (average value) of the catalyst 132. As a result, although the fuel gas passes through the vent, the catalyst 132 is deposited on the stopper member 133 without passing through the vent. The stopper member 133 of this embodiment is a disk. Further, the thickness of the stopper member 133 of this embodiment is approximately 1 mm. Furthermore, the diameter of the ventilation hole of the stopper member 133 of this embodiment is 0.3 mm. Note that the stopper member 133 may be made of glass wool.

The heater 134 is a coil type heater into which the tube material 111 is inserted. The coil portion 134A of the heater 134 is wound around at least an area of the tube material 111 that includes the combustion chamber of the second combustion temperature measuring portion 130. The coil portion 134A is connected to the constant voltage source 102 via the lead portion 134B, and generates heat when 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 section 134A is arranged apart from the combustion chamber of the first combustion temperature measurement section 120 of the tube material 111, and the catalyst 122 of the first combustion temperature measurement section 120 is not heated by the heater 134. , maintained at room temperature.

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

The data logger 103 records the signal output from the thermocouple 121, that is, the increased temperature ΔT _H [° C.] due to combustion of hydrogen in the catalyst 122 and the catalyst layer 121S of the first combustion temperature measurement unit 120. Furthermore, the data logger 103 records the signal output from the thermocouple 131, that is, the increased temperature ΔT _E [° C.] due to combustion of combustible gas other than hydrogen at the catalyst 132 of the second combustion temperature measuring section 130.

The calculation device 104 calculates the calorific value during combustion of the fuel gas supplied to the combustion temperature measuring section 110 based on the recorded contents of the data logger 103. When calculating the calorific value, the measurement values of the first flowmeter 14A and the second flowmeter 14B (see FIG. 1) are also input to the calculation device 104. As the arithmetic device 104, for example, a PC (Personal Computer) can be used.

In the calorimeter 100 configured as described above, the calculation device 104 calculates the temperature of the fuel based on the rising temperatures ΔT _H [°C] and ΔT _E [°C] measured by the thermocouples 121 and 131 and recorded in the data logger 103. Calculates the amount of heat generated when gas is combusted. The calculation device 104 stores correlation data indicating the correlation between the change in temperature measured by the thermocouples 121 and 131 and the calorific value during combustion of the fuel gas, and the calculation device 104 uses this correlation data. Then, the calorific value during combustion of the fuel gas is calculated.

Specifically, a control device (not shown) controls the first valve 15A, second valve 15B, and mixer 16 shown in FIG. The flammable gas is flowed through the pipe 12 and mixed with air in the mixer 16. As a result, fuel gas containing a predetermined concentration of combustible gas is generated. This fuel gas is supplied to the calorimeter 100 through the third pipe 13. At this time, the first flowmeter 14A measures the flow rate of the combustible gas flowing through the first pipe 11 and outputs the measurement information to the calculation device 104, and the second flowmeter 14B measures the flow rate of the combustible gas flowing through the second pipe 12. The flow rate is measured and the measurement information is output to the calculation device 104.

The constant voltage source 102 applies a voltage to the heater 134, and the base temperature of the thermocouple 131 of the second combustion temperature measuring section 130 is, for example, about 250 to 400°C. In this state, the temperature around the temperature measuring junction P of the thermocouple 131 increases due to heat generated during combustion of combustible gas other than hydrogen contained in the fuel gas. The thermocouple 131 transmits a signal corresponding to the temperature around the temperature measuring junction P to the data logger 103, and the data logger 103 stores this signal.

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

The calculation device 104 calculates the fuel gas based on 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. Calculate the amount of heat generated during combustion. Here, the calculation device 104 calculates the increased temperature ΔT _H [°C] due to hydrogen combustion output from the thermocouple 121 and stored in the data logger 103, and the flow rate information of the first flow meter 14A and the second flow meter 14B. From this, calculate the amount of heat _QH . In addition, the calculation device 104 calculates the increased temperature ΔT _E [°C] due to combustion of combustible gas other than hydrogen outputted from the thermocouple 131 and stored in the data logger 103, and the first flowmeter 14A and the second flowmeter 14B. The amount of heat _QE is calculated from the flow rate information. Then, the arithmetic unit 104 totals the amount of heat _QH and the amount of heat _QE .

Hereinafter, an experiment conducted to confirm the accuracy of calorimetry of the calorimeter 100 according to the present embodiment will be described. In this experiment, the calorific value of the test gas was measured using the calorimeter 100C according to the comparative example, and the calorimetric value of the test gas was measured using the calorimeter 100 according to the present embodiment.

FIG. 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 measurement section 110C of the calorimeter 100C according to the comparative example does not include the first combustion temperature measurement section 120 (see FIG. 2), but includes a second combustion temperature measurement section 130. That is, in the combustion temperature measurement section 110C of the comparative example, hydrogen combustion at room temperature and measurement of the rising temperature ΔT _H [°C] of hydrogen due to the combustion are not performed, but rather at a relatively high temperature (330°C in this experiment). The combustion of the test gas and the temperature increase ΔT [° C.] of the test gas due to the combustion are measured.

The combustion temperature measuring section 110C of the calorimeter 100C according to this comparative example has the following No. ～No. Five types of test gases No. 5 were supplied, and the amount of heat Q' [J] due to combustion of the test gases and the temperature rise ΔT [° C.] were measured.
No. 11: Calorific value per unit volume = 32 MJ/Nm ³ , H ₂ = 0%, CH ₄ = 100%
No. 12: Calorific value per unit volume = 36 MJ/Nm ³ , H ₂ = 0%, CH ₄ = 100%
No. 13: Calorific value per unit volume = 40 MJ/Nm ³ , H ₂ = 0%, CH ₄ = 100%
No. 14: Calorific value per unit volume = 43 MJ/Nm ³ , H ₂ = 0%, CH ₄ = 100%
No. 15: Calorific value per unit volume = 45 MJ/Nm ³ , H ₂ = 0%, CH ₄ = 100%

FIG. 4 shows No. 1 using a calorimeter 100C according to a comparative example. 11～No. It is a graph showing the results of measuring the calorific value Q′ [J] and the temperature rise ΔT [° C.] of No. 15 test gas. As shown in this graph, the determination coefficient R ² between the calorific value Q' [J] of the fuel gas and the rising temperature ΔT [°C] is 0.998, and the measurement error for the rising temperature ΔT [°C] is 0.43 at maximum. %. From the above, it was confirmed that when the fuel gas does not contain hydrogen, the amount of heat Q' [J] and the temperature rise ΔT [° C.] can be measured with high accuracy.

The combustion temperature measuring section 110C of the calorimeter 100C according to the comparative example has the following No. 16~No. Three types of test gases No. 18 were supplied, and the amount of heat Q [MJ/Nm ³ ] per unit volume due to combustion of the fuel gas was measured.
No. 16: Calorific value per unit volume = 34.5 MJ/Nm ³ , H ₂ = 20%, CH ₄ = 80%
No. 17: Calorific value per unit volume = 37 MJ/Nm ³ , H ₂ = 10%, CH ₄ = 90%
No. 18: Calorific value per unit volume = 45 MJ/Nm ³ , H ₂ = 20%, CH ₄ = 80%

FIG. 5 shows No. 1 using a calorimeter 100C according to a comparative example. 16~No. It is a graph showing the results of measuring the calorific value Q [MJ/Nm ³ ] per unit volume of No. 18 test gases. As shown in this graph, a maximum measurement error of 10.0% occurred between the true value and the calculated value of the calorific value Q [MJ/Nm ³ ] per unit volume of the test gas. Specifically, No. The calorific value Q [MJ/Nm ³ ] per unit volume of test gas No. 16 was underestimated compared to the true value by an error of 10.0%. Also, No. The calorific value Q [MJ/Nm ³ ] per unit volume of test gas No. 17 was underestimated compared to the true value by an error of 4.3%. Furthermore, No. The calorific value Q [MJ/Nm ³ ] per unit volume of test gas No. 18 was underestimated compared to the true value by an error of 8.4%.

The calorimeter 100 according to this embodiment has the following No. 1. ～No. An experiment was conducted to confirm the correlation between the concentration of hydrogen and methane and the temperature increase due to combustion ΔT _H [°C] and ΔT _E [°C] by continuously supplying the four types of test gases described in Section 4. 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 first combustion temperature measuring section 120 measured the increased temperature ΔT _H [°C]. , and measurement of the temperature increase ΔT _E [° C.] by the second combustion temperature measurement unit 130 were performed continuously.
No. 1: Calorific value per unit volume = 39.9 MJ/Nm ³ , H ₂ = 0%, CH ₄ = 100%
No. 2: Calorific value per unit volume = 34.7 MJ/Nm ³ , H ₂ = 19.2%, CH ₄ = 80.8%
No. 3: Calorific value per unit volume = 26.3 MJ/Nm ³ , H ₂ = 50%, CH ₄ = 50%
No. 4: Calorific value per unit volume = 12.8 MJ/Nm ³ , H ₂ = 100%, CH ₄ = 0%

FIG. 6 shows No. 1 in the calorimeter 100 according to this embodiment. 1~No. 4 is a table and a graph showing the results of confirming the correlation between the concentration of hydrogen and methane and the temperature increase due to combustion ΔT _H [°C] and ΔT _E [°C] by continuously supplying the test gas of No. 4. As shown in these tables and graphs, the higher the concentration of hydrogen, the higher the temperature rise ΔT H [°C] measured by the first combustion temperature measurement unit 120, and the higher the temperature rise ΔT _H [°C] measured by the second combustion temperature measurement unit 130. It was confirmed that the temperature increase ΔT _E [°C] was lower. On the other hand, the higher the concentration of methane, the higher the temperature rise ΔT _E [°C] measured by the second combustion temperature measurement unit 130, and the higher the temperature rise ΔT _H [°C] measured by the first combustion temperature measurement unit 120. was confirmed to be lower.

The calorimeter 100 according to this embodiment has the above-mentioned No. 1. ～No. An experiment was conducted to confirm the correlation between the concentration of hydrogen and methane and the temperature increase ΔT [° C.] due to combustion by intermittently supplying the test gas No. 4. In this experiment, fuel gas having a volume of 0.36 mL was intermittently supplied to the calorimeter 100 while air at a flow rate of 85 mL/min was continuously supplied to the calorimeter 100. Measurement of the temperature ΔT _H [°C] and measurement of the increased temperature ΔT _E [°C] by the second combustion temperature measuring section 130 were performed intermittently.

FIG. 7 shows No. 1 in the calorimeter 100 according to the present embodiment. 1~No. 4 is a table and a graph showing the results of intermittently supplying the test gas of No. 4 and confirming the correlation between the concentration of hydrogen and methane and the temperature rise due to combustion ΔT _H [°C] and ΔT _E [°C]. As shown in these tables and graphs, the higher the concentration of hydrogen, the higher the temperature rise ΔT H [°C] measured by the first combustion temperature measurement unit 120, and the higher the temperature rise ΔT _H [°C] measured by the second combustion temperature measurement unit 130. It was confirmed that the temperature increase ΔT _E [°C] was lower. On the other hand, the higher the concentration of methane, the higher the temperature rise ΔT _E [°C] measured by the second combustion temperature measurement unit 130, and the higher the temperature rise ΔT _H [°C] measured by the first combustion temperature measurement unit 120. was confirmed to be lower.

As explained above, the combustion temperature measurement section 110 of the calorimeter 100 according to the present embodiment burns hydrogen contained in the fuel gas at room temperature and measures the temperature increase ΔT _H [°C] due to the combustion. It includes a temperature measurement section 120 and a second combustion temperature measurement section 130 that combusts a combustible gas other than hydrogen contained in the fuel gas under heating and measures the temperature increase ΔT _E [° C.] due to the combustion. Thereby, the calorific value of fuel gas containing hydrogen can be calculated based on the increased temperature ΔT _H [°C] due to combustion of hydrogen and the increased temperature ΔT _E [°C] due to combustion of flammable gas other than hydrogen such as methane. becomes possible. Therefore, it is possible to suppress a decrease in accuracy in measuring the calorific value of the fuel gas due to hydrogen being contained in the fuel gas, and it is possible to achieve high accuracy in measuring the calorific value of the fuel gas containing hydrogen.

In addition, in the calorimeter 100 according to the present embodiment, the calculation device 104 calculates the amount of heat Q _H based on the temperature increase ΔT _H [°C] due to hydrogen combustion measured by the thermocouple 121 of the first combustion temperature measuring section 120. The amount of heat Q E is calculated based on the increased temperature ΔT _E [°C] due to combustion of combustible gas other than hydrogen, which is measured by the second combustion temperature measurement unit 130, and the total value of the amount of heat (Q _H +Q _{E )} is calculated. Calculate [℃]. This makes it possible to calculate the calorific value of the hydrogen-containing fuel gas with high accuracy based on the temperature rise ΔT _H [°C] and ΔT _E [°C] corresponding to the calorific value.

In addition, in the calorimeter 100 according to the present embodiment, the catalyst 122 of the first combustion temperature measurement section 120 and the catalyst 132 of the second combustion temperature measurement section 130 are arranged such that the fuel gas passes through the catalyst 122 of the first combustion temperature measurement section 120. The fuel gas that has passed through the catalyst 122 is accommodated in the pipe material 111 so as to pass through the catalyst 132 of the second combustion temperature measuring section 130 . That is, in the calorimeter 100 according to the present embodiment, the first combustion temperature measuring section 120 and the second combustion temperature measuring section 130 are connected in series. As a result, hydrogen contained in the fuel gas is combusted at room temperature in the first combustion temperature measurement section 120, and combustible gases other than hydrogen contained in the fuel gas are combusted under heating in the second combustion temperature measurement section 130. That is, hydrogen contained in the fuel gas and combustible gases other than hydrogen always pass through the combustion section within the pipe material 111. Therefore, hydrogen contained in the fuel gas and combustible gases other than hydrogen can be prevented from being exhausted from the pipe material 111 without being combusted.

FIG. 8 is a sectional view showing the configuration of a calorimeter 200 according to another embodiment of the present invention. As shown in this figure, the calorimeter 200 according to the present embodiment includes a combustion temperature measurement section 210 in which a first combustion temperature measurement section 120 and a second combustion temperature measurement section 130 are arranged in parallel. This combustion temperature measuring section 210 includes a first pipe material 211 and a second pipe material 212.

The third pipe 13 is connected to one end of the first pipe material 211 . Furthermore, a fourth pipe 14 branched from the third pipe 13 is connected to one end of the second pipe 212 . The first tube material 211 and the second tube material 212 are tube materials that have heat resistance against 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 tube during combustion. The first tube material 211 and the second tube material 212 of this embodiment are cylindrical ceramic tubes with an inner diameter of 4 mm. Note that the inner diameter of the first tube material 211 and the second tube material 212 is preferably 2 mm or more and 10 mm or less. Further, the first tube material 211 and the second tube material 212 may be stainless steel tubes.

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 respect to the flow direction of the fuel gas. Therefore, the fuel gas supplied from the third pipe 13 to the first pipe material 211 passes through the first combustion temperature measurement section 120. At this time, hydrogen contained in the fuel gas is combusted at room temperature, and the rising temperature ΔT _H [° C.] of hydrogen due to the combustion is measured. On the other hand, the fuel gas supplied from the fourth pipe 14 to the second pipe material 212 passes through the second combustion temperature measuring section 130. At this time, a combustible gas other than hydrogen, such as methane, contained in the fuel gas is combusted under heating, and the temperature rise ΔT _E [° C.] of the combustible gas due to the combustion is measured.

In the calorimeter 200 configured as described above, the calculation device 104 calculates the increased temperature ΔT _H [°C] due to hydrogen combustion output from the thermocouple 121 and stored in the data logger 103, and the first flow meter 14A and the first flow meter 14A. The amount of heat _QH is calculated from the flow rate information of the second flow meter 14B. Also, from the temperature increase ΔT _E [°C] due to combustion of combustible gas other than hydrogen, which is output from the thermocouple 131 and stored in the data logger 103, and the flow rate information of the first flow meter 14A and the second flow meter 14B. , calculate the amount of heat _QE . Then, the calculation device 104 adds up the calculated amount of heat Q _H and the amount of heat Q _E.

Although the present invention has been described above based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and changes may be made without departing from the spirit of the present invention. Technologies may be combined.

For example, in the above embodiment, the catalysts 122, 132 are made into granules, but the catalysts 122, 132 may be made into powders. Further, although the tube material 111, the first tube material 211, and the second tube material 212 are oriented vertically, the tube material 111, the first tube material 211, and the second tube material 212 may be oriented horizontally. Further, the structure of the combustion temperature measuring sections 110, 210 is not limited to the structure of the above embodiment, and may be changed as appropriate.

Further, in the embodiment described above, the thermocouples 121 and 131 are used as temperature measuring bodies, but other temperature measuring bodies such as a resistance temperature measuring body may be used.

100 Calorimeter 104 Arithmetic unit (calculation unit)
111 Tube material 121 Thermocouple (first temperature sensing element)
122 Catalyst (first catalyst)
131 Thermocouple (second temperature measuring element)
132 Catalyst (second catalyst)
134 Heater (heating part)
200 Calorimeter P Temperature measurement junction ΔT _H rising temperature ΔT _E rising temperature Q _H calorie (first calorie)
Q _E calorie (secondary calorie)

Claims (3)

A calorimeter that measures the calorific value of fuel gas containing hydrogen,
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 a combustible gas other than hydrogen contained in the fuel gas under heating;
a heating section that heats the second catalyst;
and a second temperature measuring element that measures the temperature increase of the combustible gas due to combustion under heating in the second catalyst. A first amount of heat is calculated based on the increased temperature of the hydrogen measured by the first temperature sensor, and a second amount of heat is calculated based on the increased temperature of the combustible gas measured by the second temperature sensor. The calorimeter according to claim 1, further comprising a calculation unit that calculates a total value of the first amount of heat and the second amount of heat. a pipe material that accommodates the first catalyst, the temperature measuring contact of the first temperature measuring body, the second catalyst, and the temperature measuring contact of the second temperature measuring body, and into which the fuel gas flows;
The first catalyst and the second catalyst are housed in the pipe material 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. The calorimeter according to claim 1 or 2.

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