JPS58115358A - Calibrating method of calorimeter for gas - Google Patents

Abstract

PURPOSE:To ensure the simple and accurate calibration of a calorimeter for gas, by detecting the temperature rise only through the combustion improving gas for a temperature sensor of a gas calorimeter which detects the temperature during the oxidation reaction through an oxidation catalyst for the combustible gas which is diluted by a large quantity of the combustion improving gas (air etc.). CONSTITUTION:A powder grain oxidation catalyst 2 is enclosed into a case 1 of a heat-resisting glass pipe, etc. Then the gas G diluted with a large quantity of the combustion improving gas like air, oxygen, etc. is supplied to the catalyst 2 from a branch pipe 3 via a temperature sensor 4. A calorimeter detects the temperature rise due to the oxidation by a temperature sensor 5. When the calibration is given to the calorimeter, only the combustion improving gas is made to pass and a heater 11 set around the sensor 5 of the catalyst 2 is heated with the conduction via a lead wire 10 piercing through a base 9 of a branch pipe of the case 1. In this case, the temperature rise is detected and the calibration is carried out from the prescribed calorific value required for heating and the output of detection of the sensor 5 and in response to the cooling conditions due to the combustion improving gas and equivalent to those required when the gas G is measured. In such a way, the calibration is possible easily without using the standard gas.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of calibrating a gas calorimeter mainly used for measuring the calorific value of fuel gas.

Recently, there has been a demand for continuous and instantaneous measurement of the calorific value of gas for the purpose of controlling the refining process of city gas, etc. or for trading. A gas calorimeter has been developed that encloses a powdery oxidation catalyst and installs a temperature sensor inside it, detects the temperature during the oxidation reaction of the gas by the oxidation catalyst, and calculates the calorific value of the gas. However, when calibrating such a gas calorimeter, conventionally, a standard gas with a known calorific value was used, and the detected calorific value indicated by this gas was compared with the known calorific value of the standard gas. However, there are drawbacks such as the need to prepare standard gas each time.

The present invention has the purpose of fundamentally solving the drawbacks of the conventional methods, and in addition to passing only the combustion supporting gas to the calorimeter mentioned above, the temperature sensor is heated by electrical means, thereby reducing the temperature rise caused by this. The present invention provides a highly effective method for calibrating a gas calorimeter that performs detection and calibration.

Hereinafter, the present invention will be explained in detail with reference to FIG. 1 showing an outline diagram of an embodiment.

In Fig. 1, a powdery oxidation catalyst 2 is enclosed in a case 1 that forms a gas passage using a circular tube made of Biolex glass, and a large amount of combustion supporting gas such as air or oxygen is used. A temperature sensor 4 is provided on the side of the branch pipe 3 into which the diluted gas G flows, and a temperature sensor 5 is also provided inside the oxidation catalyst 2. The gas G flowing from the branch pipe 3 passes through the temperature sensor 4 to the oxidation catalyst 2, where an oxidation reaction occurs, and then it is discharged from the branch pipe 6 as exhaust gas RG. It has become.

Further, the lead wire T of the temperature sensor 4 #5 is drawn out to the outside through a base $ having an insulating and airtight property, which is attached to both ends of the case 10.

In addition, a heater 11 as an electric heating means with a lead wire 10 passing through a similar base 9 is provided inside the oxidation catalyst 2 and around the temperature sensor 5, and the heater 11 generates heat when energized. , the temperature sensor 5 is heated.

This temporary temperature sensor 4, 5. As the oxidation catalyst 7, it is preferable to use an alumina ceramic tube with thin platinum wires etc., and as the oxidation catalyst 7, CumolCOO% MnO
3. Crabs, ZnO1Fears, VsOi,
Mob, etc. can be used.

However, if multiple sets are mixed and used, the characteristics of each set will work complementarily, making it possible to obtain a more robust oxidation reaction for various combustible components. It's all over the place.

In addition, if alumina powder → inert powder is mixed into the oxidation catalyst T, mutual bonding due to fusion of the powder and granular oxidation catalyst is prevented, and this prevents the O-threshold wax from decreasing. It is true.

Furthermore, a glass cooler 12 is filled in the nine gaps in the case 1 and in the branch pipes 3 and 6, thereby fixing the temperature sensor 4 and the oxidation catalyst 2.

Therefore, if the gas G diluted with the combustion supporting gas is passed into the case 1 while the heater 11 is not energized, the temperature before the oxidation reaction is detected by the temperature sensor 4, and the oxidation catalyst 2 A reaction occurs, and the temperature due to the heat generated is detected by the temperature sensor 5,
The gas GO calorific value can be determined by determining the temperature increase due to the oxidation reaction in response to the gas GO calorific value.

However, if the detected force of the temperature sensor 5 is corrected according to the gas temperature before the oxidation reaction indicated by the detected force of the temperature sensor 4, the gas GO calorific value can be determined more accurately.

On the other hand, when performing calibration, combustion supporting gas and gas G
In addition to passing only the same amount of combustion supporting gas as the total flow rate, if the heater 11 generates a predetermined amount of heat and is energized to heat the temperature sensor 5, the temperature rise due to this will be equal to the predetermined amount of heat. Therefore, it is possible to perform calibration based on the relationship between the predetermined amount of heat and the detection power of the temperature sensor 5.

The reason why only the combustion support gas is passed during calibration is to maintain the same conditions as the cooling effect of the flowing mixed gas during actual use.

FIG. 2 shows a case in which a metal oxide semi-enveloped body is used as the oxidation catalyst 2, and an electrode for passing a current through the oxidation catalyst is used as the electric heating means, replacing the heater 11 in FIG. Electrodes 22 and 23 made of platinum wires whose IJ-)' wires 21 pass through the base 8 are provided in the oxidation catalyst 2 opposite to each other via the temperature sensor 5.

Therefore, when electricity is applied between the electrodes 22 and 23, a current passes through the oxidation catalyst 2 and ohmic heat is generated.If this calorific value is set to a predetermined value, calibration is performed in the same manner as in Fig. 1. be able to.

Note that the case 1 may be made of any material as long as it has heat resistance, airtightness, and chemical inertness.
Its shape can also be selected, and the temperature sensors 4 and 5 are
The same applies to a thermistor type semiconductor device, and in place of the glass wool 120, another material exhibiting the same properties may be used.

Further, the heater 11 may be provided outside the case 1 in the same manner, and the electrodes 22 and 23 may be made of not only platinum but also other inert metals, and various other modifications are possible.

As is clear from the above explanation, according to the present invention, a gas calorimeter can be easily and accurately calibrated. When calibrating, a noticeable effect can be obtained.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views showing embodiments of the present invention. 1...Case, 2...Oxidation catalyst, 4゜5...
・Temperature sensor, 11. Heater, 22. 23. Electrode. Special fraud applicant Yamatake Honeywell Co., Ltd./Agent
Person Masaki Yamakawa (#1 or 1 person) Figure 1 0 Figure 2

Claims (3)

[Claims] (1) A gas calorimeter comprising a particulate oxidation catalyst provided in a passage for gas diluted with a large amount of combustion supporting gas, and a temperature sensor that detects the temperature during the oxidation reaction by the oxidation catalyst. , wherein only the combustion-supporting gas is passed through the gas passage, the temperature sensor is heated by an electric heating means, and a temperature rise due to the heating is detected and calibrated. How to calibrate a calorimeter. (2) A method for calibrating a gas calorimeter according to claim 1, wherein the electric heating means is a heater that generates heat by energizing the entire circumference of the heater, which is slightly smaller than 1%. (3) Calibration of a gas calorimeter according to claim 1, characterized in that a metal oxide semiconductor is used as an oxidation catalyst, and an electrode for passing a current to the oxidation catalyst is used as an electric heating means. Method.