JPS58115356A - Calorimeter for gas - Google Patents

Abstract

PURPOSE:To ensure the accurate measurement of the calorific value of fuel gas in a continuous and instantaneous way, by providing a powder grain oxidation catalyst layer and then a heater into a gas flowing path and setting temperature heaters before the catalyst layer, between the catalyst layer and the heater and after the heater respectively. CONSTITUTION:The end pipes 2 and 3 are stuck to both ends of a case 1 which forms a flowing path of a fuel gas G. Then a temperature sensor 10, a powder grain oxidation catalyst layer 14, a temperature sensor 11, a heater 13 and a temperature sensor 12 are set successively from the side of the gas inlet (side of the pipe 2). Each of the sensors 10-12 is formed by enclosing a platinum net wires, etc. into a pipe of alumina ceramic, etc. These sensors are then enclosed by the glass wool 16, etc. and put into branch pipes 4, 5 and 6 respectively. The heater 13 is put through a branch pipe 7. The layer 14 is made of Cu2O, V2O5, etc., and Al2O3 15 is packed around the heater 13. Then the calorific value Q of the gas G is obtained accurately from equationsI-III, where t0 is the temperature of G obtained before the oxidation reaction, t1 is the temperature of G obtained after the oxidation reaction, t2 is the temperature of gas G2 due to the calorific value (q) supplied from the heater 13 and Cp is the specific heat at constant pressure of CO2 produced from G.

Description

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

In recent years, 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 purposes. A method has been proposed in which a fixed sensor is provided and the amount of heat generated by the reaction between the gas and the catalyst is detected as a change in the resistance value of the platinum 11.

However, in such a method, only a small portion of the gas comes into contact with the sensor, which reduces measurement accuracy, and when fixing the catalyst to a platinum wire, etc., a slurry of the catalyst is applied and then baked. The mechanical strength is weak due to the use of ultra-fine platinum wire, etc., which requires advanced technology.
In addition, the reliability of the sensor is deteriorated due to the fact that the solvent remaining when the catalyst is made into a slurry has an adverse effect.

The present invention has the purpose of fundamentally solving the drawbacks of the conventional method, and by sequentially providing a powdery oxidation catalyst and a heating heater in the gas passage, the gas temperature before the oxidation reaction can be controlled. The present invention provides an extremely effective gas calorimeter that detects the temperature of the residue after reaction and the temperature of the gas after heating, and determines the calorific value of the gas based on these results.

Hereinafter, the urine invention will be described in detail with reference to cross-sectional views showing examples.

In the figure, nine-end tubes 2.3 made of the same material are airtightly fixed to both ends of a case 1 that forms a gas passage using a circular tube such as Biolex glass. While the gas G flows in from the case 1, the gas G that has passed through the case 1 is discharged from the end pipe 3 as exhaust gas RG.

Also, inside the case 1, a first temperature sensor 10 and a first temperature sensor 10 having a lead wire 9 passing through an insulating and airtight pace 8 that is fitted into the branch pipes 4 to 7 and fixed in an airtight manner. A second temperature sensor 11 and a third temperature sensor 12 are inserted, as well as a heater 13 for heating, and a powdery oxidation catalyst is inserted between the first and second temperature sensors 10 and 11. 14 is filled, and the second and third temperature sensors 11 and 1
Alumina powder particles 15 are filled around the heater 13 inserted between the heater 13 and the heater 13 .

In addition, glass wool 1 is placed around the temperature sensors 10 to 12.
6 is filled and fixes them.

For this reason, the oxidation catalyst 14 and the heater 13 are sequentially arranged for the flow of the gas G, and the temperature of the gas G before the oxidation reaction is detected by the first sensor 10. , depending on the second temperature sensor 11, the oxidation catalyst 1
The temperature after the oxidation reaction of gas G by 4 is detected,
Depending on the third temperature sensor 12, after the oxidation reaction, the heater 1
3, the temperature of the heated gas G is detected.

Therefore, the amount of heat Q of the gas G can be determined by the detection power of each temperature sensor 10 to 12.

That is, the oxidation reaction heat quantity QVi of gas G, the constant pressure ratio/heat of CO2 produced by this is Cp, the temperature before the oxidation reaction is tos, and the oxidation reaction source degree is t! Then, it is given by the following equation.

Q=Cp (tr to )---(1)
Furthermore, if the heater 13 supplies the gas G after the oxidation reaction with a heat amount of [2, q Calo IJ-, the temperature of the heated gas G will be t! Then, the constant pressure specific heat Cp of Cow is expressed by the following equation.

Cp=q/ (tz tt) ・・・・・・
(2) Now, by substituting equation (2) into equation (1), the heater 13 supplies q calories of heat, and the first to third temperature sensors 11 to 13 measure the temperature j.
The M-IQ of the gas G can be obtained by calculating o+il+L-value and calculating the equation (3) based on these detection forces.

Please do not check the deterioration status of the oxidation catalyst 14.
In order to detect the combustible components remaining in the exhaust gas RG, a known combustible gas sensor is sealed in the end pipe 3@.
This may be used to detect combustible components, or the exhaust gas RG may be inspected using a portable combustible gas detector.

Furthermore, if the oxidation catalyst 14 deteriorates, the amount of gas G supplied during sitting time may be reduced so that all of the supplied gas G undergoes an oxidation reaction, allowing continuous use. .

In addition, each of the temperature sensors 10 to 12 is preferably a tube made of alumina ceramic or the like with a platinum mesh wire sealed therein, and the oxidation catalyst 14 is preferably a tube made of alumina ceramic or the like.
, Mn0m, Crx03, ZnO,F@
mol, V2051 Mo5s 1 etc. are used.

However, it is preferable to use a mixture of a plurality of types, since the characteristics of each type act complementary to each other, so that a more reliable oxidation reaction can be obtained for various combustible components.

Note that it is effective to mix inert particles such as alumina powder into the oxidation catalyst 14 because this prevents the granular oxidation catalysts from bonding to each other due to fusion and prevents their surface area from decreasing.

Therefore, the powdery oxidation catalyst 14 with a large surface area and all of the gas G that flows through it come into complete contact, and all of the gas G takes part in the oxidation reaction, so the amount of heat of the gas G can be detected completely and accurately. In addition, the overall reliability is greatly improved because it does not use atomized ultrafine platinum wire, and it does not require catalyst application or adhesion.

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 each temperature sensor 1°0~1°
The same effect can be obtained by using a semiconductor material such as a thermistor for the temperature sensors 10 to 12. In addition, other substances exhibiting the same properties may be used instead of the alumina powder particles 15 and the glass coolant 16, or each of the temperature sensors 10 to 12 Various modifications are possible, such as providing the casing 1 on the outer wall side of the case 1.

As is clear from the above description, according to the present invention, an accurate and highly reliable calorimeter can be obtained with a simple and easy-to-manufacture configuration. This allows remarkable effects to be achieved in refining process management and trading of fuel gas, etc.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the present invention. 1... Case, 10-12... 1st to 3rd temperature sensor, 13... 9 heater, 14... Oxidation catalyst, G... Gas. Patent applicant Yamatake Honeywell Co., Ltd. Agent Masaki Yamakawa (and one other person)

Claims (2)

[Claims] (1) A gas calorimeter characterized by comprising a powdery oxidation catalyst sequentially provided in a gas passage and a heater for heating. (2) The gas calorimeter according to claim 1, characterized in that a mixture of a plurality of types is used as the #formation catalyst.