JP2021050971A - Calorimeter and heat quantity measuring method - Google Patents

Abstract

To provide a calorimeter and a heat quantity measuring method with which it is possible to improve the accuracy of the heat quantity to find, as compared with the case where the heat quantity of a gas is found while a mass flow rate is maintained constant.SOLUTION: A calorimeter 10 comprises a combustion unit 20 for catalytically burning a gas; a supply unit 50 for supplying the combustion unit 20 with a gas; and an information processing unit 78 including a derivation unit for deriving the heat quantity of a gas and a control unit for controlling each unit. The supply unit 50 supplies the combustion unit 20 with a predetermined volume of a gas. The derivation unit derives the heat quantity of a gas by an increased temperature of the combustion unit due to the gas supplied by the supply unit 50 being catalytically burnt in the combustion unit 20.SELECTED DRAWING: Figure 1

Description

The present invention relates to a calorimeter for measuring the calorific value of a gas, and a calorimeter measuring method.

In the calorimeter described in Patent Document 1, gas is introduced by a gas introduction pipe in the vicinity of the oxidation catalyst heated by the heating element, and the introduced gas is catalyst-burned. Then, the calorific value of the gas can be obtained by measuring the rising temperature ΔT of the heat storage unit provided around the oxidation catalyst. Here, regarding the introduction of gas, it is necessary to control the volume flow rate in principle of measurement, but since it is generally difficult to control the volume flow rate of gas with high accuracy, it is necessary to replace it with the control of mass flow rate. The gas whose mass flow rate is controlled is actually introduced by the gas introduction pipe.

Japanese Unexamined Patent Publication No. 2015-87165

In a conventional calorimeter, the temperature of the heat storage section rises due to catalytic combustion of a gas having a constant mass flow rate, and the calorific value of the gas is obtained by measuring the temperature of the raised heat storage section. In the method of obtaining the calorific value of the gas with a constant mass flow rate, for example, when the gas component changes, the volumetric flow rate of the gas varies, and the accuracy of the obtained calorific value is low.

An object of the present invention is to improve the accuracy of the obtained calorific value as compared with the case where the calorific value of the gas having a constant mass flow rate is obtained.

In the calorimeter according to the first aspect, a combustion unit for catalytically burning gas, a supply unit for supplying a predetermined volume of gas to the combustion unit, and a gas supplied by the supply unit are catalysts in the combustion unit. It is characterized by including a lead-out unit that derives the calorific value of the gas according to the temperature of the combustion unit that rises due to combustion.

According to this configuration, the supply unit supplies a predetermined volume of gas to the combustion unit, and the outlet unit raises the combustion unit by heating the gas supplied from the supply unit in the combustion unit and performing catalytic combustion. The calorific value of the gas is derived from the rising temperature ΔT of.

Therefore, for example, even when the gas component changes, the amount of gas burned in the catalyst section can be uniformly determined as the volume, so that the amount of heat of the gas with a constant mass flow rate can be obtained. In comparison with the above, the accuracy of the required amount of heat can be improved.

The calorimeter according to the second aspect is the calorimeter according to the first aspect, wherein the supply unit has a measuring pipe having a predetermined volume, a flowing state in which gas flows through the measuring pipe, and a measuring pipe. A flow state in which the gas flow is cut off to hold the gas in the measuring pipe and a supply state in which air is flowed through the measuring pipe to push out the gas held in the measuring pipe and supply the gas to the combustion portion. It is characterized by being provided with a gas supply valve for switching paths.

According to this configuration, in the supply valve, after the gas flows through the measuring pipe, the gas flow to the measuring pipe is cut off and the measuring pipe holds the gas. Further, air is flowed through the measuring pipe to push out the gas held in the measuring pipe and supply the gas to the combustion part.

In this way, by temporarily holding the gas in the measuring pipe having a constant volume, a predetermined volume of gas can be supplied to the combustion unit.

The calorimeter according to the third aspect is the calorimeter according to the second aspect, in which a temperature sensor for detecting the temperature of the gas held in the measuring tube and a pressure for detecting the pressure of the gas held in the measuring tube are used. A sensor is provided, and the derivation unit corrects the volume of gas supplied by the supply unit and derives the calorimeter of the gas by using the detection result of the temperature sensor and the detection result of the pressure sensor. It is characterized by.

According to this configuration, in the calorimeter, the lead-out unit corrects the volume of gas supplied by the supply unit by using the detection result of the temperature sensor and the detection result of the pressure sensor. Further, the derivation unit derives the calorific value of the gas according to the temperature of the combustion unit that rises due to catalytic combustion of the corrected volume of gas.

Therefore, the accuracy of the required calorific value can be improved as compared with the case where the calorimeter is not provided with the temperature sensor and the pressure sensor.

The calorimeter according to the fourth aspect is the calorimeter according to any one of the first to third aspects, wherein the supply unit periodically supplies gas to the combustion unit, and the combustion unit periodically supplies gas. The gas supplied to the vehicle is catalytically burned, and the lead-out unit periodically derives the calorimeter of the gas according to the temperature of the combustion unit that rises due to the catalytic combustion.

According to this configuration, the supply unit periodically supplies gas to the combustion unit, and the combustion unit catalytically burns the periodically supplied gas. Further, the lead-out unit periodically derives the calorific value of the gas by the rising temperature raised by the catalytic combustion. In this way, the calorimeter can continuously (intermittently) derive the calorific value of the gas.

The calorific value measuring method according to the fifth aspect is a flow step of flowing gas through a measuring pipe having a predetermined volume, and after the flowing step, the gas flow to the measuring pipe is cut off and gas is supplied to the measuring pipe. The holding step of holding, the extrusion step of extruding the gas held in the measuring tube in the holding step, the combustion step of catalytically burning the gas extruded in the extrusion step, and the temperature raised by the combustion step of the gas It is characterized by including a derivation process for deriving the amount of heat.

According to this configuration, in the holding step, the gas is temporarily held in the measuring pipe by blocking the flow of the gas to the measuring pipe. Further, in the extrusion step, the gas held in the measuring tube is extruded in the holding step, and in the combustion step, the gas extruded in the extrusion step is catalytically burned. In this way, by catalytically burning a gas having a predetermined volume in the combustion step, the accuracy of the required calorific value can be improved as compared with the case where the calorific value of the gas having a constant mass flow rate is obtained.

In the calorific value measuring method according to the sixth aspect, in the calorific value measuring method according to the fifth aspect, the sinking step, the holding step, the extrusion step, the combustion step, and the derivation step are periodically carried out in this order. It is characterized by doing.

According to this configuration, the sinking step, the holding step, the extrusion step, the combustion step, and the derivation step are periodically performed in this order. As a result, in the calorific value measuring method, the calorific value of the gas can be continuously (intermittently) derived.

In this embodiment, the accuracy of the obtained calorific value can be improved as compared with the case where the calorific value of the gas having a constant mass flow rate is obtained.

It is a block diagram which showed the calorimeter which concerns on 1st Embodiment of this invention. It is a block diagram which showed the calorimeter which concerns on 1st Embodiment of this invention, and was used for explaining the process of measuring the calorific value. It is a block diagram which showed the calorimeter which concerns on 1st Embodiment of this invention, and was used for explaining the process of measuring the calorific value. It is a block diagram which showed the calorimeter which concerns on 1st Embodiment of this invention, and was used for explaining the process of measuring the calorific value. It is a block diagram which showed the calorimeter which concerns on 1st Embodiment of this invention, and was used for explaining the process of measuring the calorific value. It is a block diagram which showed the information processing part provided in the calorimeter which concerns on 1st Embodiment of this invention. It is a figure which showed the relationship between the temperature and time detected by the combustion part provided in the calorimeter which concerns on 1st Embodiment of this invention in a graph. It is a drawing which showed the relationship between the rise temperature and the calorie which were input in advance to the lead-out part provided in the calorimeter which concerns on 1st Embodiment of this invention. (A) (B) The calorimeter derived using the calorimeter according to the first embodiment of the present invention and the flow rate of the gas detected using the calorimeter according to the comparative embodiment with respect to the embodiment of the present invention are shown in the table. It is a drawing shown. It is a block diagram which showed the calorimeter which concerns on the comparative embodiment with respect to 1st Embodiment of this invention. It is a block diagram which showed the calorimeter which concerns on 2nd Embodiment of this invention. It is a block diagram which showed the information processing part provided in the calorimeter which concerns on 2nd Embodiment of this invention.

<First Embodiment>
An example of the calorimeter and the calorimeter measuring method according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 10. The calorimeter of the present embodiment is used to measure the calorific value of gas. The arrow UP shown in the figure indicates the upper part in the vertical direction.

(Overall configuration of calorimeter 10)
As shown in FIG. 1, the calorimeter 10 is attached to, for example, a gas pipe 200 extending in the vertical direction. The gas pipe 200 is, for example, a pipe used for delivering gas from a city gas factory.

The calorimeter 10 is an information processing unit including a combustion unit 20 for catalytically burning gas, a supply unit 50 for supplying gas to the combustion unit 20, a derivation unit 80 for deriving the calorific value of gas, and a control unit 90 for controlling each unit. It is provided with a unit 78 (see FIG. 6).

The "calorific value" is the thermal energy per unit volume of the gas, and [MJ / Nm ³ ] may be used as the unit.

[Combustion unit 20]
The combustion unit 20 includes a detection unit heat storage material 24, a detection unit catalyst 30 having a detection unit heating element 28, a detection unit thermocouple 34, a gas introduction pipe 36, and a heating circuit unit 38.

-Detector catalyst 30-
As an example, the detection unit catalyst 30 is a spherically solidified oxidation catalyst, and a Pt-based catalyst, a Pd-based catalyst, or the like can be used. The detection unit catalyst 30 is provided with a detection unit heating element 28, and the detection unit heating element 28 is an electric body and generates heat by a current flowing through the heating circuit unit 38.

-Detector heat storage material 24-
The detection unit heat storage material 24 is arranged so as to surround the detection unit catalyst 30 from above and from the side. As the heat storage material 24 of the detection unit, a metal material having high thermal conductivity such as aluminum can be used. As a result, the detection unit heat storage material 24 stores the generated heat in order to indirectly grasp the amount of heat generated by the detection unit catalyst 30. The shape of the heat storage material 24 of the detection unit may be a hollow spherical shape that completely covers the periphery of the catalyst 30 of the detection unit.

-Detector thermocouple 34-
The detection unit thermocouple 34 is provided in the detection unit heat storage material 24 in order to detect the temperature of the detection unit heat storage material 24. The detection unit thermocouple 34 may be provided inside the detection unit catalyst 30.

-Gas introduction pipe 36-
The gas introduction pipe 36 is arranged so as to connect the space surrounded by the heat storage material 24 of the detection unit and the hexagonal valve 52 described later of the supply unit 50. One end of the gas introduction pipe 36 penetrates the heat storage material 24 of the detection unit and opens to the catalyst 30 side of the detection unit, and the other end of the gas introduction pipe 36 is connected to the port 52e of the hexagonal valve 52.

-Heating circuit part 38-
The heating circuit unit 38 has a power supply 38a, and when a voltage predetermined by the power supply 38a is applied, a current flows through the detection unit heating element 28 and the detection unit heating element 28 generates heat as described above. It has become like.

In this configuration, in the combustion unit 20, the gas supplied from the supply unit 50 is catalytically burned by the detection unit catalyst 30 heated by the detection unit heating element 28 to generate heat, and the detection unit heat storage material 24 is the detection unit. The heat generated by the catalyst 30 is stored. Then, the detection unit thermocouple 34 detects the temperature of the detection unit heat storage material 24. Regarding the detection unit thermocouple 34, the temperature of the detection unit catalyst 30 may be detected.

[Supply unit 50]
As shown in FIG. 1, the supply unit 50 includes a hexagonal valve 52, a gas supply unit 56 that supplies (samples) the gas to be measured to the hexagonal valve 52, and a gas discharge that discharges gas from the hexagonal valve 52. A unit 60 and a measuring unit 64 for measuring the gas to be measured are provided. Further, the supply unit 50 includes a carrier gas supply unit 66 that supplies air, which is a carrier gas, to the hexagonal valve 52.

-Six-way valve 52-
The hexagonal valve 52 has six ports 52a, 52b, 52c, 52d, 52e, 52f, and the connection between these ports 52a, 52b, 52c, 52d, 52e, 52f is controlled by the control unit 90 (FIG. 6). See). The hexagonal valve 52 is an example of a supply valve.

The port 52a is connected to the gas supply unit 56, and the port 52b is connected to the gas discharge unit 60. Further, the port 52c is connected to one end of the measuring unit 64, and the port 52d is connected to the other end of the measuring unit 64.

Further, as described above, the port 52d is connected to the other end of the gas introduction pipe 36, and the port 52f is connected to the carrier gas supply unit 66.

-Gas supply unit 56-
The gas supply unit 56 includes a sampling pipe 56a that connects the port 52a and the gas pipe 200, and a valve 56b that opens and closes the flow path of the sampling pipe 56a. In this configuration, the valve 56b is controlled by the control unit 90 to open and close the flow path of the sampling tube 56a.

-Gas discharge unit 60-
The gas discharge unit 60 includes a discharge port 60a for discharging gas to the atmosphere, a connecting pipe 60b for connecting the discharge port 60a and the port 52b, and a valve 60c for opening and closing the flow path of the connecting pipe 60b.

-Weighing unit 64-
The measuring unit 64 includes a cylindrical measuring pipe 64a extending in one direction, a connecting pipe 64b connected to one end of the measuring pipe 64a in the longitudinal direction, and the measuring pipe 64a in the longitudinal direction. It has a connecting pipe 64c connected to the end. Specifically, one end of the connecting pipe 64b is connected to the measuring pipe 64a, and the other end of the connecting pipe 64b is connected to the port 52d. Further, one end of the connecting pipe 64c is connected to the measuring pipe 64a, and the other end of the connecting pipe 64c is connected to the port 52c. In the present embodiment, the volume of the measuring tube 64a as an example is 0.5 [ml] as an example.

-Carrier gas supply unit 66-
The carrier gas supply unit 66 has an air pipe 66a having one end connected to the port 52f and the other end open to the atmosphere, and an air pipe 66a provided in the middle of the air pipe 66a to supply air as a carrier gas from the air pipe 66a to the hexagonal valve 52. It is equipped with a supply pump 66b. Further, the carrier gas supply unit 66 includes an MFC 66c (mass flow controller) provided between the port 52f and the pump 66b in the air pipe 66a. In this embodiment, the MFC 66c (mass flow controller) is provided, but any device may be used as long as it controls the flow rate of the fluid.

In this configuration, the supply unit 50 is switched to four states by the control of each unit by the control unit 90 shown in FIG. Specifically, as shown in FIG. 2, the flow path of the sampling pipe 56a is blocked by the valve 56b, and the flow path of the connecting pipe 60b is blocked by the valve 60c. Further, the pump 66b is stopped. As a result, the supply unit 50 is stopped. In the stopped state, no gas is flowing through the hexagonal valve 52.

As shown in FIG. 3, the sampling tube is connected by the valve 56b in a state where the port 52a and the port 52d are connected, the port 52b and the port 52c are connected, and the port 52e and the port 52f are connected. The flow path of 56a is opened, the flow path of the connecting pipe 60b is opened by the valve 60c, and the pump 66b is operated. As a result, the supply unit 50 is in a sink state.

In the sink state, as shown by the thick line in FIG. 3, the gas flowing through the gas pipe 200 passes through the ports 52a and 52d of the hexagonal valve 52 via the valve 56b of the sampling pipe 56a, and the connecting pipe 64b and the measuring pipe 64a. And flows through the connecting pipe 64c. Further, the gas flowing through the connecting pipe 64c is discharged from the discharge port 60a via the ports 52c and 52b of the hexagonal valve 52 and the valve 60c of the connecting pipe 60b. Further, the operating pump 66b causes air to flow through the air pipe 66a and is supplied to the combustion unit 20 via the ports 52a and 52d.

Further, after the sink state, the flow path of the sampling tube 56a is blocked by the valve 56b as shown in FIG. As a result, the supply unit 50 is in the holding state.

In the holding state, as shown by the thick line in FIG. 4, the measuring pipe 64a is filled with a predetermined volume of gas, the flow path of the sampling pipe 56a is blocked by the valve 56b, and the gas discharge portion is blocked by the valve 60c. The pressure of the measuring tube 64a is in the state of atmospheric pressure because the pressure is open. In other words, a predetermined volume of gas is held in the measuring tube 64a.

Further, after the holding state, as shown in FIG. 5, the connection between the port 52a and the port 52d is released, the connection between the port 52c and the port 52b is released, the port 52a and the port 52b are connected, and the port The 52c and the port 52f are connected, and the port 52d and the port 52e are connected. As a result, the supply unit 50 is in the supply state.

In the supply state, as shown by the thick line in FIG. 5, the air flowing through the air pipe 66a by the operating pump 66b passes through the ports 52f and 52c of the hexagonal valve 52, and is connected pipe 64c, measuring pipe 64a and connecting pipe 64b. Flow. Further, the gas flowing through the connecting pipe 64b is supplied to the combustion unit 20 via the ports 52d and 52e.

In this way, air is flowed through the measuring pipe 64a to push out the gas held in the measuring pipe 64a and supply the gas to the combustion unit 20. In other words, the supply unit 50 supplies the combustion unit 20 with a predetermined volume of gas. In the present embodiment, the flow velocity of the air pushing out the gas held in the measuring pipe 64a is 120 [ml / min] as an example.

[Information processing unit 78]
As shown in FIG. 6, the information processing unit 78 includes a derivation unit 80 that derives the amount of heat of the gas, and a control unit 90 that controls each unit.

-Control unit 90-
The control unit 90 controls each unit to operate the calorimeter 10. The control of each unit by the control unit 90 will be described together with the operations described later.

-Delivery unit 80-
The lead-out unit 80 derives the calorific value of the gas based on the temperature detected by the detection unit thermocouple 34.

Specifically, the relationship between the amount of heat of the gas and the temperature rise ΔT of the detection unit heat storage material 24 that has risen due to the catalytic combustion of the gas is recorded in advance in the lead-out unit 80. The horizontal axis of the graph shown in FIG. 8 is the rising temperature ΔT, and the vertical axis is the calorific value of the gas. In this way, the calorific value of the gas increases in proportion to the rising temperature ΔT. This relationship is input to the derivation unit 80.

Further, the rising temperature ΔT is calculated by the lead-out unit 80 based on the temperature detected by the detection unit thermocouple 34. The horizontal axis of the graph shown in FIG. 7 is the elapsed time, and the vertical axis is the temperature detected by the detection unit thermocouple 34. As shown in this graph, the derivation unit 80 monitors the temperature detected by the detection unit thermocouple 34 and calculates the rising temperature ΔT raised by the catalytic combustion of the gas.

In this configuration, the derivation unit 80 derives the calorific value of the gas by the rising temperature ΔT (peak value) calculated by monitoring the temperature detected by the detection unit thermocouple 34.

(Action)
Next, the operation of the calorimeter 10 will be described together with the calorimeter 210 according to the comparative form. Regarding the calorimeter 210 according to the comparative form, a part different from the calorimeter 10 will be mainly described. First, the configuration of the calorimeter 210 will be described.

[Structure of calorimeter 210]
As shown in FIG. 10, the calorimeter 210 includes a combustion unit 20, a supply unit 250 that supplies gas to the combustion unit 20, and an information processing unit 278.

The supply unit 250 includes a connecting pipe 220 that connects the gas pipe 200 and the combustion unit 20, and a supply pipe 230 that supplies air (oxygen) for burning the gas in the combustion unit 20. The connecting pipe 220 is provided with MFC 224 in this order from the gas pipe 200 side to the combustion unit 20 side. One end of the supply pipe 230 is connected to a portion between the MFC 224 and the combustion unit 20 in the connecting pipe 220, and the pump 232 and the MFC 234 are connected to the supply pipe 230 from the other end side to the one end side of the supply pipe 230. It is provided in this order.

Further, the information processing unit 278 includes a control unit 290 that controls each unit and a derivation unit 280 that derives the amount of heat of the gas.

[Action of calorimeters 10 and 210]
Next, a calorimeter measuring method for measuring the calorific value of the gas flowing through the gas pipe 200 using the calorimeters 10 and 210 will be described.

-Action of calorimeter 210-
In the calorimeter 210 shown in FIG. 10, the calorific value of the gas supplied to the combustion unit 20 by the supply unit 250 is measured.

In the non-operating calorimeter 210, the pump 232 is stopped. Further, the voltage is not applied to the heating circuit unit 38 by the power supply 38a.

When the calorimeter 210 is operated, the control unit 290 operates the pump 232 and applies a voltage to the heating circuit unit 38 by the power supply 38a. As a result, the gas having a constant mass flow rate is supplied to the combustion unit 20 by the MFC 224, and the air having a constant mass flow rate is supplied to the combustion unit 20 by the MFC 234.

In this way, gas and air having a constant mass flow rate are continuously supplied to the combustion unit 20. The gas supplied to the combustion unit 20 is catalytically burned by the detection unit catalyst 30 (oxidation catalyst) heated by the detection unit heating element 28, which generates heat when a voltage is applied to the heating circuit unit 38 by the power supply 38a.

Due to this combustion, the temperature of the detection unit catalyst 30 rises, and the temperature of the detection unit heat storage material 24 also rises accordingly. Further, the temperature of the heat storage material 24 of the detection unit is measured by the thermocouple 34 of the detection unit. Then, based on the temperature of the detection unit heat storage material 24 measured by the detection unit thermocouple 34, the extraction unit 280 derives the calorific value of the gas.

Here, since the volumetric flow rate supplied to the combustion unit 20 of the calorimeter 210 has been measured, the measurement result will be described.

In the calorimeter 210 shown in FIG. 10, gas having a constant mass flow rate is supplied to the combustion unit 20 by the MFC 224. That is, in the calorimeter 210, the calorific value of the gas having a constant mass flow rate is obtained.

Here, the table shown in FIG. 9B shows the measurement results measured for the volumetric flow rate of the gas supplied to the combustion unit 20 by the MFC 224. The volumetric flow rate of the gas was measured using a wet gas meter between the portion of the connecting pipe 220 to which the supply pipe 230 is connected and the combustion unit 20.

Since the flow rate of the gas is small, first, the volumetric flow rate of the air is measured by supplying only the air without supplying the gas. In the table NO1a shown in FIG. 9 (B), only the air is 3 The measurement result in the case of circulation is shown. In the case of air only, the average value of the three measurements measured was 95.35 [ml / min].

NO2a in the table shown in FIG. 9B shows the measurement results when gas and air are allowed to flow three times. The gas of NO2a is a gas having a calorific value of 45 [MJ / Nm ³ ] calculated from the components and the like. When the gas of NO2a and air were flowed, the average value of the three measurements measured was 99.65 [ml / min].

The volumetric flow rate of gas only, which is obtained by subtracting the average value of air from each measured value of NO2a, is 4.50 [ml / min], 4.35 [ml / min], and 4.05 [ml / min]. there were. Further, the average value of the volumetric flow rate of gas alone was 4.30 [ml / min].

NO3a in the table shown in FIG. 9B shows the measurement results when gas and air are allowed to flow three times. The gas of NO3a is a gas having a calorific value of 40 [MJ / Nm ³ ] calculated from the components and the like. When the gas of NO3a and air were flowed, the average value of the three measurements measured was 100.09 [ml / min].

The volumetric flow rate of gas only, which is obtained by subtracting the average value of air from each measured value of NO3a, is 4.73 [ml / min], 4.82 [ml / min], and 4.66 [ml / min]. there were. Further, the average value of the volumetric flow rate of gas alone was 4.74 [ml / min].

From this result, the volumetric flow rate of the gas of NO3a differs from the flow rate of the gas of NO2a by about 10%. That is, in the calorimeter 210, the volumetric flow rate differs by about 10% due to the difference in the type of gas.

Further, the volumetric flow rate of the gas is proportional to the temperature rise measured by the combustion unit 20. Therefore, it is proportional to the volumetric flow rate of the gas and the amount of heat of the gas to be measured. That is, in the calorimeter 210, the calorific value of the gas to be measured has an error of about 10 [%] with respect to the calorific value (true calorific value) of the gas calculated from the components and the like.

-Action of calorimeter 10-
In the calorimeter 10 shown in FIG. 1, the calorific value of the gas supplied to the combustion unit 20 by the supply unit 50 is measured.

In the calorimeter 10 in the non-operating state, the flow path of the sampling tube 56a is blocked by the valve 56b. Further, the pump 66b is stopped, and no voltage is applied to the heating circuit unit 38 by the power supply 38a. As a result, as shown in FIG. 2, no gas is flowing through the hexagonal valve 52.

When the calorimeter 10 is operated, the port 52a and the port 52d are connected, the port 52b and the port 52c are connected, and the port 52e is connected by the control of each part by the control unit 90, as shown in FIG. And the port 52f are connected.

In this state, the valve 56b opens the flow path of the sampling pipe 56a, the valve 60c opens the flow path of the connecting pipe 60b, and the pump 66b operates. Further, the pump 66b is operated, and a voltage is applied to the heating circuit unit 38 by the power supply 38a.

As a result, the gas flowing through the gas pipe 200 flows through the sampling pipe 56a, flows through the connecting pipe 64b, the measuring pipe 64a, and the connecting pipe 64c in this order via the ports 52a and 52d, and then passes through the ports 52c and 52b. It flows through the connecting pipe 60b and is discharged from the discharge port 60a (flowing step). The process of flowing gas through the measuring tube 64a in this way is generally called charging.

Further, air, which is a carrier gas, flows through the air pipe 66a by the operating pump 66b, and is supplied to the combustion unit 20 via the ports 52a and 52d.

Then, when the gas is discharged from the discharge port 60a, the flow path of the sampling pipe 56a is blocked by the valve 56b by the control of each part by the control unit 90, as shown in FIG. As a result, the supply unit 50 is in the holding state, and in the holding state, as shown by the thick line in FIG. 4, the measuring tube 64a is filled with a predetermined volume of gas, and the valve 56b allows the sampling tube 56a to be filled. The pressure of the measuring pipe 64a is in the state of atmospheric pressure because the flow path is closed and the gas discharge portion is opened by the valve 60c. In other words, a predetermined volume of gas is held in the measuring tube 64a (holding step).

Further, when the measuring pipe 64a is filled with gas, the control of each part by the control unit 90 releases the connection between the port 52a and the port 52d, and the connection between the port 52c and the port 52b, as shown in FIG. Is released, the port 52a and the port 52b are connected, the port 52c and the port 52f are connected, and the port 52d and the port 52e are connected.

As a result, air flows through the air pipe 66a, passes through the ports 52f and 52c, flows through the connecting pipe 64c, the measuring pipe 64a and the connecting pipe 64b in this order, and then burns via the ports 52d and 52e. It is supplied to the unit 20. In this way, by flowing the air in the direction opposite to that at the time of charging, a predetermined volume of gas filled in the measuring pipe 64a is pushed out by the air, and the combustion unit is passed through the ports 52d and 52e. It flows to the gas introduction pipe 36 of 20. In this way, air is flowed through the measuring pipe 64a to push out the gas filled in the measuring pipe 64a and supply it to the combustion unit 20 (extrusion step).

The gas flowing through the gas introduction pipe 36 is catalytically burned by the detection unit catalyst 30 (oxidation catalyst) heated by the detection unit heating element 28, which generates heat when a voltage is applied to the heating circuit unit 38 by the power supply 38a (combustion step). ).

Due to this combustion, the temperature of the detection unit catalyst 30 rises, and the temperature of the detection unit heat storage material 24 also rises accordingly. Then, the temperature of the heat storage material 24 of the detection unit is detected by the thermocouple 34 of the detection unit.

The derivation unit 80 shown in FIG. 6 monitors the temperature detected by the detection unit thermocouple 34, and derives the temperature rise ΔT (see FIG. 7) of the detection unit heat storage material 24 that has risen due to the catalytic combustion of gas. Further, the out-licensing unit 80 derives the calorific value of the gas from the derived relationship between the ascending temperature ΔT and the pre-input heat quantity of the gas and the ascending temperature ΔT (deriving step).

By repeating such steps, the supply unit 50 periodically supplies the gas to the combustion unit 20, and the combustion unit 20 catalytically burns the periodically supplied gas. Further, the lead-out unit 80 periodically derives the calorific value of the gas by the rising temperature ΔT raised by the catalytic combustion. In other words, the sinking process, the holding process, the extrusion process, the combustion process, and the derivation process are periodically performed in this order.

Here, FIG. 9A shows a table showing the measurement results obtained by measuring the calorific value of the three types of gas using the calorimeter 10 and the calorific value (true calorific value) calculated from the components of the three types of gas. It is shown.

First, for each gas, the rising temperature ΔT was measured about 10 times each, and the average value, the value obtained by subtracting 2σ derived from the variation of the measurement about 10 times from the average value, and 2σ as the average value were used. The added value was derived. Further, the calorific value of the gas was derived from the relationship between the derived value, the calorific value of the gas input in advance, and the rising temperature ΔT.

In the gas of NO1b in the table shown in FIG. 9 (A), the average value of the rising temperature ΔT 10 times is 141.89 [° C.], and the value obtained by subtracting 2σ from the average value is 141.21 ° C., which is 2σ. The value added to the average value was 142.57 [° C.]. Further, when the rising temperature ΔT is 141.21 [° C.], the calorific value of the gas derived from the relationship between the pre-input heat quantity of the gas and the rising temperature ΔT is 39.87 [MJ / Nm ^3]. ], When the rising temperature ΔT is 142.57 [° C.], the calorific value of the gas derived from the relationship between the pre-input heat quantity of the gas and the rising temperature ΔT is 40.00 [MJ / Nm]. ³ ].

The derived calorific value of the gas (39.87 [MJ / Nm ³ ] and 40.00 [MJ / Nm ³ ]) is the true calorific value calculated from the components of the gas (39.94 [MJ / Nm ^3]). ]), About 0.17 [%] different.

In the gas of NO2b in the table shown in FIG. 9 (A), the average value of the rising temperature ΔT 10 times is 168.75 [° C.], and the value obtained by subtracting 2σ from the average value is 167.82 ° C., which is 2σ. The value added to the average value was 169.68 [° C.]. Further, when the rising temperature ΔT is 167.82 [° C.], the calorific value of the gas derived from the relationship between the pre-input heat quantity of the gas and the rising temperature ΔT is 42.41 [MJ / Nm ^3]. ], When the rising temperature ΔT is 169.68 [° C.], the calorific value of the gas derived from the relationship between the pre-input heat quantity of the gas and the rising temperature ΔT is 42.59 [MJ / Nm]. ³ ].

The derived calorific value of the gas (42.41 [MJ / Nm ³ ] and 42.59 [MJ / Nm ³ ]) is the true calorific value calculated from the components of the gas (42.51 [MJ / Nm ^3]). ]) Is different by about 0.23 [%].

In the gas of NO3b in the table shown in FIG. 9 (A), the average value of the temperature rise ΔT 10 times is 195.59 [° C.], and the value obtained by subtracting 2σ from the average value is 194.62 ° C., which is 2σ. The value added to the average value was 196.57 [° C.]. Further, when the rising temperature ΔT is 194.62 [° C.], the calorific value of the gas derived from the relationship between the pre-input heat quantity of the gas and the rising temperature ΔT is 44.97 [MJ / Nm ^3]. ], When the rising temperature ΔT is 196.57 [[° C.], the calorific value of the gas derived from the relationship between the pre-input heat quantity of the gas and the rising temperature ΔT is 45.16 [MJ / MJ /]. It was Nm ^3].

The derived calorific value of the gas (44.97 [MJ / Nm ³ ] and 45.16 [MJ / Nm ³ ]) is the true calorific value calculated from the components of the gas (45.07 [MJ / Nm ^3]). ]) Is different by about 0.22 [%].

As described above, in the calorimeter 10, the amount of heat measured has a variation of about 0.23 [%] with respect to the true amount of heat calculated from the gas components and the like, even if the variation in the measurement of 2σ is taken into consideration. It fits.

(Summary)
As described above, in the calorimeter 10, the accuracy of the obtained calorimeter can be improved as compared with the case where the calorimeter is measured by using the calorimeter 210 for obtaining the calorimeter of the gas having a constant mass flow rate.

Further, in the calorimeter 10, the gas filled (held) in the measuring pipe 64a is extruded into air as a carrier gas and supplied to the combustion unit 20. In this way, by temporarily holding the gas in the measuring pipe 64a, a predetermined volume of gas can be supplied to the combustion unit 20.

Further, in the calorimeter 10, the supply unit 50 periodically supplies the gas to the combustion unit 20, and the combustion unit 20 catalytically burns the periodically supplied gas. Further, the lead-out unit 80 periodically derives the calorific value of the gas by the rising temperature ΔT raised by the catalytic combustion. In this way, the calorimeter 10 can continuously (intermittently) derive the calorific value of the gas.

Further, in the calorific value measurement method, in the extrusion process, air is flowed through the measuring pipe 64a to push out the gas once held in the measuring pipe 64a and supply it to the combustion unit 20, and in the combustion process, the supplied gas is catalytically burned. .. As a result, the calorific value measuring method can improve the accuracy of the calorific value to be obtained as compared with the calorimeter measuring method of the calorimeter 210 which obtains the calorific value of the gas having a constant mass flow rate.

Further, in the calorific value measuring method, the sinking process, the holding process, the extrusion process, the combustion process, and the derivation process are periodically performed in this order. In this way, in the calorific value measuring method, the calorific value of the gas can be continuously (intermittently) derived.

<Second Embodiment>
An example of the calorimeter and the calorimeter measuring method according to the second embodiment of the present invention will be described with reference to FIGS. 11 and 12. In addition, about 2nd Embodiment, the part different from 1st Embodiment will be mainly described.

(Constitution)
As shown in FIG. 11, the calorimeter 310 according to the second embodiment includes a combustion unit 20, a supply unit 350 that supplies gas to the combustion unit 20, a lead-out unit 380 that derives the calorific value of the gas, and each unit. It includes an information processing unit 378 (see FIG. 12) including a control unit 90 for controlling.

[Supply unit 350]
As shown in FIG. 11, the supply unit 350 includes a hexagonal valve 52, a gas supply unit 56, a gas discharge unit 60, a measurement unit 364 for measuring the gas to be measured, and a carrier gas supply unit 66. ing.

-Weighing unit 364-
The measuring unit 364 includes a measuring pipe 64a, a connecting pipe 64b, a connecting pipe 64c, and a detecting unit 364d for detecting the state of the gas held in the measuring pipe 64a.

The detection unit 364d is arranged in the middle portion of the connecting pipe 64b, and is held by the temperature sensor 366 that detects the temperature of the gas held in the measuring pipe 64a and the measuring pipe 64a as shown in FIG. It is equipped with a pressure sensor 368 that measures the pressure of the gas.

[Information Processing Department 378]
As shown in FIG. 12, the information processing unit 378 includes a derivation unit 380 that derives the amount of heat of the gas, and a control unit 90 that controls each unit.

-Delivery unit 380-
The lead-out unit 380 derives the calorific value of the gas based on the temperature detected by the detection unit thermocouple 34, the temperature of the gas detected by the temperature sensor 366, and the pressure of the gas detected by the pressure sensor 368.

Specifically, the relationship between the amount of heat of the gas and the temperature rise ΔT of the detection unit heat storage material 24 that has risen due to the catalytic combustion of the gas is recorded in advance in the lead-out unit 380.

Further, the rising temperature ΔT is calculated by the lead-out unit 380 based on the temperature detected by the detection unit thermocouple 34.

In this configuration, in the lead-out step, the lead-out unit 380 uses the gas temperature detected by the temperature sensor 366 and the gas pressure detected by the pressure sensor 368 to hold the volume of gas in the measuring tube 64a. Is corrected, and then the calorific value of the gas is derived.

For example, in the derivation step, the derivation unit 380 uses the temperature of the gas detected by the temperature sensor 366 and the pressure of the gas detected by the pressure sensor 368 to determine the volume of gas held in the measuring tube 64a. Correct the volume under predetermined temperature and pressure conditions. Then, the out-licensing unit 380 derives the calorific value of the gas by the rising temperature ΔT of the detection unit heat storage material 24 that rises due to the catalytic combustion of the corrected volume of gas.

(Summary)
As described above, in the calorimeter 310, the lead-out unit 380 derives the calorific value of the gas by the rising temperature ΔT of the detection unit heat storage material 24 which has risen due to the catalytic combustion of the gas having the corrected volume. Therefore, the accuracy of the calorific value of the required gas can be improved as compared with the case where the calorimeter is not provided with the temperature sensor and the pressure sensor.

Although the present invention has been described in detail with respect to specific embodiments, the present invention is not limited to such embodiments, and various other embodiments can be taken within the scope of the present invention. That is clear to those skilled in the art. For example, in the above embodiment, the volume of the gas supplied by using the measuring tube is set to a predetermined volume, but for example, the gas stored in the measuring tube having a predetermined volume is used as the gas. The amount of heat of may be derived.

Further, in the above embodiment, the calorimeter 10 is used to intermittently derive the calorific value of the gas, but the calorimeter 10 may be used to derive the calorimeter of the gas only once.

Further, in the above embodiment, the flow path is switched by using the hexagonal valve 52, but it may be an eight-way valve, a combination of two-way valves, or another valve.

Further, although not particularly described in the above embodiment, the calorimeter 10 may be used as a unit so that the calorimeter of the gas can be derived at different places. In this case, the lead-out unit 80, 380, and the control unit 90 may be carried separately from the device.

Further, although not particularly described in the second embodiment, the position where the pressure sensor 368 for measuring the pressure of the gas held in the measuring pipe 64a is arranged is limited to the middle portion of the connecting pipe 64b. Any position may be used as long as it can directly or indirectly detect the pressure of the gas held in the measuring pipe 64a. When the pressure of the gas held in the measuring pipe 64a is atmospheric pressure, for example, the pressure of the gas held in the measuring pipe 64a is indirectly controlled by a pressure sensor that detects the pressure of the gas flowing inside the gas pipe 200. It may be detected as a target.

Further, although not particularly described in the second embodiment, the position where the temperature sensor 366 for measuring the temperature of the gas held in the measuring pipe 64a is arranged is limited to the middle portion of the connecting pipe 64b. Any position can be used as long as it can directly or indirectly detect the temperature of the gas held in the measuring pipe 64a. For example, a temperature sensor may be arranged on the connecting pipe 60b or the like to indirectly detect the temperature of the gas held in the measuring pipe 64a.

10 Calorimeter 20 Combustion unit 50 Supply unit 52 Six-way valve (supply valve)
64a Measuring tube 80 Derivation unit 310 Calorimeter 350 Supply unit 380 Derivation unit

Further, as described above, the port 52 e is connected to the other end of the gas introduction pipe 36, and the port 52 f is connected to the carrier gas supply unit 66.

Claims (6)

The combustion part that catalytically burns the gas and
A supply unit that supplies a predetermined volume of gas to the combustion unit, and a supply unit.
A derivation unit that derives the calorific value of the gas according to the temperature of the combustion unit that has risen due to catalytic combustion of the gas supplied by the supply unit in the combustion unit.
A calorimeter equipped with. The supply unit
A measuring tube with a predetermined volume and
A state in which gas flows through the measuring tube, a holding state in which the flow of gas to the measuring tube is blocked and the gas is held in the measuring tube, and a state in which air is flowed through the measuring tube and held in the measuring tube. A gas supply valve that switches the flow path to the supply state that pushes out the gas and supplies it to the combustion unit.
The calorimeter according to claim 1. A temperature sensor that detects the temperature of the gas held in the measuring tube and
A pressure sensor for detecting the pressure of the gas held in the measuring tube is provided.
The calorimeter according to claim 2, wherein the derivation unit corrects the volume of the gas supplied by the supply unit by using the detection result of the temperature sensor and the detection result of the pressure sensor, and derives the calorific value of the gas. Total. The supply unit periodically supplies gas to the combustion unit.
The combustion unit catalytically burns the periodically supplied gas.
The calorimeter according to any one of claims 1 to 3, wherein the lead-out unit periodically derives the calorific value of the gas according to the temperature of the combustion unit that rises due to catalytic combustion. A flow process in which gas flows through a measuring tube with a predetermined volume,
After the sinking step, a holding step of blocking the flow of gas to the measuring pipe to hold the gas in the measuring pipe, and a holding step of holding the gas in the measuring pipe.
In the holding step, an extrusion step of extruding the gas held in the measuring tube and
A combustion process in which the gas extruded in the extrusion process is catalytically burned, and
A derivation process for deriving the calorific value of the gas based on the temperature raised by the combustion process, and
A calorific value measuring method. The calorific value measuring method according to claim 5, wherein the sinking step, the holding step, the extrusion step, the combustion step, and the derivation step are periodically performed in this order.

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