RU30992U1 - Automated Gaseous Fuel Thermal Value Analyzer - Google Patents

Description

AUTOMATIC ANALYZER OF GAS-FUEL FUEL HEATNESS

The utility model relates to the field of analytical technology, namely, to means for automatic control of gaseous heat value

A well-known automatic analyzer of the heat value of gaseous FUEL (Measurements in the industry. Handbook. Iod. I. Irofos. M .: Metallurgy, 1980. S. 440-441), containing a burner located in the inner cavity of the liquid heat exchanger, at the outlet and entrance of which are installed thermocouple batteries, as well as a potentiometer and equipment to stabilize the flow of the analyzed gas and water. Evaluation of the heat value of gaseous fuel by such an analyzer is carried out by the difference of the signals of the thermocouple batteries, which arises due to the heating of water in the heat exchanger by the burning analyzed gas.

The disadvantage of this analyzer is that it provides information only on the howling volumetric heat of combustion of the analyzed gas, which is not a unique commodity characteristic of the quality of gaseous fuels.

The closest in technical essence is an automatic analyzer of the heat value of gaseous fuels (Farzane N. G., Ilyasov L. V. Automatic calorimeter for measuring the lower volumetric heat of combustion of gases. Gas industry. No. 8, 1970. P. 29-31). containing a chamber, in the bottom of which a burner is installed to form a flame in the inner cavity of the chamber, connected via a tee to a hydrogen pipe and the outlet of a column connected by its inlet to the outlet nozzle of the dispenser, two inlet nozzles of which are connected to the gaseous fuel pipeline and the carrier gas pipeline, thermocouple.

located above the burner and connected to a normalizing converter, and a potentiometer. Determination of the heat value of gaseous fuels is carried out by the temperature of the gaseous products of combustion.

The disadvantage of this analyzer is that it allows you to measure only the lowest volumetric heat of combustion of gaseous fuels which only partially determines the quality of gaseous fuels, and when commodity accounting of gaseous fuels, in addition to information about the lower volumetric heat of combustion, information about the Wobbe number is also used, which depends on lower volumetric heat of combustion, and the density of gaseous fuels.

The objective of the utility model is to obtain the possibility of a comprehensive automatic assessment of the thermal value of gaseous fuels.

The technical result - the creation of an automatic analyzer that allows you to get information about the lower volumetric heat of combustion, Wobbe number and density of gaseous fuel.

The technical result is achieved in that an automatic analyzer of the heat value of gaseous fuels, containing a chamber, in the bottom of which a burner is installed to form a flame in the inner cavity of the chamber, connected by a tee to a hydrogen pipe and the output of the column, connected by its input to the output nozzle of the dispenser, two input nozzles which is connected to the gaseous fuel pipeline and the carrier gas pipeline, a thermocouple located above the burner and connected to a normalizing converter w, and the potentiometer, further comprises an auxiliary column, a turbulent throttle, a differential pressure gauge with a unified output electrical signal, a summing computing device and a square root extraction device, as well as a computing dividing device, the input of the auxiliary column connected to the output nozzle of the dispenser, a turbulent throttle installed at the output of the almighty column and to its input and output a differential pressure gauge is connected.

the output of the differential pressure gauge is connected to the input of the summing computing device, the output of the square root extraction device is connected to the input of the divider of the dividing device, the output of the normalizing converter is connected to the input of the dividend of the dividing device, and the output of the latter is connected to the potentiometer.

This design of the analyzer allows in the course of one analysis to measure the lower volumetric heat of combustion, density and Wobbe number of the analyzed gaseous fuel through the use of an auxiliary column, a turbulent throttle, differential pressure gauge and computing devices.

Compared with the prototype of the claimed design has a distinctive feature in the combination of elements and their relative position.

A circuit diagram of a gaseous fuel heat value analyzer is shown in FIG. 1.

An automatic analyzer of the heat value of gaseous fuels contains a chamber 1, in the bottom 2 of which a burner 3 is installed to form a flame in the inner cavity of the chamber 1, connected via a tee 4 to a hydrogen pipe 5 and the output 6 of the column 7, connected by its input 8 to the output nozzle 9 of the dispenser 10 The two inlet panels of the tank 11 and 12 of the dispenser 10 are connected respectively to a gaseous fuel pipe 13 and a carrier gas pipe 14, a thermocouple 15 located above the burner 3 and connected to a normalizing converter 16, and otsentiometer 17. The analyzer also contains an auxiliary column 18, a turbulent throttle 19, a differential pressure gauge 20 connected in series to the summing computing device 21, the square root extraction device 22 and the computing dividing device 23. Moreover, the input 24 of the auxiliary column 18 is connected to the outlet nipple 9 of the dispenser 10, turbulent the inductor 19 is installed at the output 25 of the auxiliary column and to its input 26 and output 27 is connected difmano. Gs /// G / L7

meter 20, while the output of the differential pressure gauge 20 is connected to the input of the summing computing device 21, the output of the square root extraction device 22 is connected to the input of the divider of the dividing device 23, the output of the normalizing converter 16 is connected to the input of the divisible dividing device, the output of the latter is connected to the potentiometer 17. To maintain the constancy of the flow rate of air, hydrogen, the analyzed gas and the carrier gas in the composition of the analyzer included flow stabilizers 28-31. To exclude turbulent air flows, a divider 32 is installed in chamber 1, and a programmer 33 is included in the analyzer to control the operation of the analyzer. The main measuring elements of the analyzer, namely, chamber 1, dispenser 10, columns 7 and 18, turbulent throttle 19 and differential pressure gauge 20 are located in thermostat 34, thermostatically controlled at a temperature of 45 ° C. The analyzer uses a multipoint potentiometer 17, which makes it possible to register the signals of the dividing device 23, the normalizing converter 16 and the differential pressure gauge 20. The measuring circuit of the analyzer consists of two parts: calorimetric and densimetric. The calorimetric part includes: a chamber 1 with a burner 3, a column 7, a thermocouple 15 and a normalizing transducer 16, and is designed to measure the lower volumetric heat of combustion of gaseous fuels. The densimetric part includes: a column 18, a turbulent throttle 19 and a differential pressure gauge 20, and is designed to measure the density difference of the analyzed gaseous fuel and gas carrier (for example, air).

The automatic analyzer of the heat value of gaseous fuels is a measuring device of cyclic action and has two operating modes: Preparation and Analysis, which are implemented as follows. Continuously, constant flow rates of these gases are supplied to the analyzer from flow stabilizers 28-31 of air, hydrogen, the analyzed gas and the carrier gas (in the particular case there may be air). Hydrogen burns in the burner 3, the air divider 32 creates a uniform flow cross-section

air. The temperature of the gaseous products of combustion is measured by a thermocouple 15 and a normalizing transducer 16.

In the Preparation mode, into which the dispenser 10, and with it the entire analyzer, are switched by the command of the programmer 33, the carrier gas enters the burner 3 through the column 7 and the dispenser 10, and the analyzed gas flows through the dosed volume of the dispenser 10, rinsing this volume from gas carrier. In the Preparation mode, only hydrogen burns in the burner 3, and the thermocouple signal 15 formed in this case is taken as the initial level of the calorimetric part of the analyzer. At the same time, through the dispenser 10 and the column 18, the carrier gas with a constant volumetric flow rate enters the turbulent throttle 19. The pressure drop that arises on the throttle 19 is measured by a differential pressure gauge 20, and the signal formed at the output of the differential pressure gauge 20 is taken as the initial signal level of the densimeter part of the analyzer. Preparation mode lasts 30-60 s. Then, at the command of the programmer 33, dispenser 10. and with it the entire anapizer, is transferred to the Analysis mode of operation. In this case, a sample of the analyzed gas is introduced into the carrier gas stream and fed through the probe 9 simultaneously to the columns 7 and 18 in a predetermined ratio that is determined by the aerodynamic properties of the elements of the calorimetric and densimetric parts of the analyzer. Columns 7 and 18 create a small (15-30 s) time delay in the supply of the analyzed gas from the dispenser 10 to the burner 3 and the turbulent throttle 19. This delay is necessary to complete the transients that occur when switching the dispenser 10, which cause fluctuations in the initial signals of both parts analyzer. Upon receipt of a sample of the analyzed gas in burner 3, combustible components are burned in a hydrogen flame. This increases the temperature of the flow of gaseous products of combustion, increases the signal of the thermocouple 15 and the output signal of the normalizing Converter. At the same time, when the sample of the analyzed gas enters the turbulent throttle 19, the pressure difference on this throttle changes, and therefore the output

the signal of the differential pressure gauge 20. The volume of the sample taken by the dispenser 10. is selected so that the signals at the output of the normalizing transducer 16 and the differential pressure gauge 20 have a trapezium shape, the height of which is an informative parameter, which increases the measurement accuracy (Farzane N.G., Ilyasov L.V. , Azim-zade A. Yu. Automatic detectors of gases and liquids. M: Energoatomizdat, 1983. P. 12). In this case, the signal of the normalizing converter Ui is proportional to the lower volumetric heat of combustion Q of the gaseous fuel, and the signal of the differential pressure gauge U2 is proportional to the difference in the densities of the gaseous fuel p and the carrier gas p.,, Under normal conditions, i.e.

U, K, .Q, (1)

U2 K2- (p-p,. ,,), (2)

where K | and C3 are the conversion coefficients of the calorimetric and densimetric parts of the analyzer. The signal U2 from the output of the differential pressure gauge is fed to a summing device, where a constant signal Uo is added to it, the value of which is determined by the density of the carrier gas p, „(Uo ,,). The output signal of the ultrasonic device 21 is determined by the expression:

UZ + U2 + and K2- (P - P,.) + K2-P ,,, K2-p. (3)

in the device 22, the square root is extracted from the ultrasound signal, and the signal of this device is determined by the expression:

, .vW7, (4)

where K, -p, is a constant coefficient;

PIJ - air density under normal conditions;

R/

ROTP - - the relative density of the analyzed gas (by air).

Signal U | the normalizing converter and the signal U4 of the device 22 are supplied respectively to the inputs of the Divisible and the Divisor of the divider device 23. The output signal Us of this device is determined by the Wobbe number of the analyzed gaseous fuel, namely: I.- -K-8e,,. k, where - t - coefficient (5) of the analyzer conversion by the number of Wob

6 - - NUMBER Wobbe.

Signal and ,, as well as signals U | and LF, fed to the input of a multipoint potentiometer 17. All the described operations are repeated in each cycle of the automatic analysis of gaseous fuels. The time of one analyzer operation cycle is 1 - 2 minutes.

Thus, the proposed gaseous fuel thermal value anapizer provides complete control over the quality of gaseous fuels., As it provides information on the lower calorific value, Wobbe number and density of this fuel.

The advantage of the proposed technical solution is:

- simplicity of control of the heat value of gaseous fuel;

-complexity of control;

the possibility of using gaseous fuels in commodity accounting systems.

The proposed analyzer can be implemented on the basis of serial industrial automatic chromatographic analyzers., Differential pressure gauges with a unified electrical output signal and serial electrical computing devices.

The analyzer can be widely used to control the thermal value of gaseous fuels in main pipelines and gas pipelines of industrial enterprises.

Claims (1)

An automatic analyzer of the heat value of gaseous fuels, containing a chamber, in the bottom of which there is a burner for forming a flame in the inner cavity of the chamber, connected by a tee to a hydrogen pipe and the output of a column connected by its input to the outlet nozzle of the dispenser, the two input nozzles of which are connected respectively to the gas pipe fuel and gas carrier piping, a thermocouple located above the burner and connected to a normalizing converter, and a potentiometer, distinguishing The analyzer additionally contains an auxiliary column, a turbulent throttle, a differential pressure gauge with a unified output electric signal, a summing computing device and a square root extraction device, and a computational dividing device connected in series, the input of the auxiliary column being connected to the outlet of the dispenser, the turbulent throttle is installed at the output of the auxiliary column and to its input and output a differential pressure gauge is connected, while the output of the differential pressure gauge under is connected to the input of the summing computing device, the output of the square root extraction device is connected to the input of the divider of the dividing device, the output of the normalizing converter is connected to the input of the dividend of the dividing device, and the output of the latter is connected to the potentiometer.