JPH1151853A - Apparatus for sealing dirt due to film-like flow of fluid at internal gas monitoring window or optical sensor part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing method for an analyzer measuring the properties of a gas-like fluid, e.g. the atmosphere, a process gas or an exhaust gas in a flue, through an optical method while preventing a furnace/flue monitoring window from being contaminated in which the sensor part can be prevented from being contaminated. SOLUTION: A film-like flow of sealing fluid, e.g. the air, is produced at the boundary between a flow of a gas 3 not to be measured and a transparent glass-like plate 14. A previously pressurized sealing fluid 15 supplied from a piping, a pump, or the like, and blown out toward the surface of the transparent glass-like plate 14 as a film-like flow through a narrow elongated gap before being sucked in the downstream. When a circulation system is employed in a circuit for supplying the sealing gas, consumption of the sealing fluid can be minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a window for monitoring the inside of a furnace or a flue such as a heating furnace, a boiler or an incinerator, and an analyzer for measuring the components of the atmosphere or combustion exhaust gas or process gas by an optical method. In the sensor portion of the above, the surface where the transparent glass plate comes into contact with the non-measurement gas is sealed with a clean fluid such as air to prevent contamination of the transparent glass plate and a supply circuit of the sealing fluid. .

[0002]

2. Description of the Related Art Conventionally, there has been a problem that a transparent glass plate for monitoring the inside of a furnace or a flue is contaminated by internal gas and cannot be seen. On the other hand, in devices such as online optical gas component analyzers that use infrared rays or lasers, the concentration of components determined by transmitting light such as infrared rays or lasers to the non-measurement gas and calculating from the absorption spectrum of the light is calculated. Is calculated, but the transparent glass plate is in contact with the non-measurement gas regardless of whether the measurement target is air, flue gas or process gas.

[0003] For this reason, the transparent glass plate is contaminated by moisture and impurities contained in the non-measurement gas, and the transmittance of light is reduced with time, resulting in an increased error. In the case of flue gas or process gas, it was necessary to install a gas pretreatment device to remove dust and moisture in the gas in order to reduce this error and prevent the sampling line for the analyzer from being clogged. . In addition, even if the pretreatment device is attached, the sensor section becomes dirty after a certain period of time, so that it is necessary to periodically clean the sensor section.

[0004]

In such a method in which the non-measuring gas is in contact with the transparent glass plate, the monitoring window becomes invisible due to dirt, and the measurement accuracy of the sensor unit such as an analyzer is reduced. It takes time and labor for maintenance such as cleaning. Even if a pretreatment device is installed in the gas sampling line, the filters and dehumidifiers in the gas sampling line often have a lot of failures, which requires labor for maintenance, reduces the reliability of measurement, and reduces the equipment such as analyzers. Was large and expensive.

Further, in the case of a flue gas or process gas analyzer, the sampling line becomes longer, and there is a problem that the analysis delay time is increased to 15 to 30 minutes.

An object of the present invention is to prevent contamination of a monitoring window by sealing dirt on a transparent glass plate with a simple structure, to reduce errors and failures of equipment such as an optical analyzer, Response delay is reduced, and in the case of flue gas or process gas, a sampling device including a pretreatment device is not required,
An object of the present invention is to provide a small and inexpensive measuring device.

[0007]

DISCLOSURE OF THE INVENTION The present invention relates to a window for monitoring gas in a furnace or a flue, and an analytical method for measuring the components of a gaseous fluid using an optical method such as transmitting infrared rays or laser beams. With a device such as a meter, in a structure with a transparent glass-like plate, the surface where the transparent glass-like plate comes into contact with the non-measurement gas is sealed by creating a film-like flow with a clean fluid such as air, It is characterized in that the plate is prevented from being stained.

An outlet having a structure capable of blowing out a clean fluid such as air into a film is installed on the surface of the transparent glass plate in contact with the non-measurement gas, and is constantly blown.

[0009] The blown fluid is sucked from a suction port provided downstream of the blowout port, so that the flow of the sealing fluid is made smooth and the amount of the fluid flowing into the non-measurement gas side is minimized. To do it. In order to feed the fluid into the apparatus, a compressed air source can be used in the plant, or a pump can be used. As a method for sucking the fluid, a pump or an ejector can be used.

As a means for blowing and sucking a fluid into and out of the seal portion, there is a method in which a pump or an ejector is attached to both the blowing side and the suction side. In addition, a sealing fluid circuit that can minimize the consumption of the sealing fluid has been realized. This circuit is characterized by providing a fresh injection line in the circulation line and injecting a small amount of sealing fluid so that non-measurement gas will not enter the sealing fluid from the seal part and the sealing fluid will not be contaminated by circulation alone. Circuit.

In this case, a measurement error due to the absorption of light by the fluid to be sealed may be a concern. However, in this type of equipment such as an analyzer, two optical fibers are laid, one is used for measurement, and the other is used for measurement. The optical fiber uses the transmission error for compensation, and uses the difference between the two spectra as measurement data. By installing a glass plate with the same specifications as the measurement optical fiber on the compensation optical fiber and giving the same flow of the fluid being blown, the error factor that the fluid blown for sealing exerts on the measurement is completely eliminated. Can be.

When measuring flue gas or process gas,
According to the present invention, a long sampling line and a pretreatment device for preventing contamination or blockage can be eliminated.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of the present invention.
FIG. 1 shows a configuration diagram of an online analysis system 1 for optically measuring gas components of flue gas and process gas. The measurement system 1 includes a sample line 4 branched from a main pipe 2, an optical sensor unit 10, an analyzer controller 30, an optical system 30 as an optical transmission path for infrared rays, lasers, and the like, and a sealing fluid circuit 20. ing.

The unmeasured gas 3 is branched from the main pipe 2 to the sample line 4, passes through the sensor section 10 of the analyzer, and returns to the main pipe 2.

Light such as infrared light and laser is transmitted from the analyzer controller 30 through the optical fiber 31 to the sensor unit 1.
0, and passes through the seal portion 11 and the non-measurement gas 3 and returns to the analyzer controller 30. At this time, an absorption spectrum by the gas is measured, and a target measured value such as a component concentration is output through numerical processing.

In an optical system, the attenuation of light in an optical fiber and the absorption spectrum of a sealing fluid cause measurement errors. Therefore, a compensation optical fiber line 32 is often provided for the purpose of canceling the errors. In this case, if the effect of the sealing fluid is to be compensated, the same shape as the sealing portion 11 of the sensor portion 10 is inserted into the compensation line 32.

FIG. 2 is a structural diagram of the seal portion 11 in the sensor portion 10. The seal portion 11 includes a sealing fluid blower 41 that blows out a fluid in a film form, and a sealing fluid suction device 44 that sucks the fluid.

The sealing fluid sent from the inlet is supplied to the pipe 1
Through 2, it is sent to the inlet of the sealing fluid blower 41. The fluid is diffused in a fan shape in the blowing section 41, blows out in a film form from a narrow and elongated fluid blowing port 42, and flows toward the fluid blowing port 43 while covering the surface of the transparent glass plate 14.

The fluid sucked from the fluid inlet 43 flows toward the outlet of the fluid blower 44 and flows into the pipe 13.
Is sucked.

FIG. 3 is a configuration diagram of a circuit 20 for supplying a sealing fluid to the sealing portion 11. The sealing fluid supply circuit 20 includes a pump 21, a circulation line including an air supply line 23, a branch pipe 13, a return line 22, and a branch pipe 12, and a fresh line 25 for supplying a fresh fluid. And

The sealing fluid discharged from the pump 21 is sent to the seal section 11 through the air supply line 23 and the branch pipe 13 of the circuit, and is sucked toward the suction sides 12 and 22.
Return to the suction side of the pump and circulate.

In order to prevent contamination of the circulating fluid due to mixing of the non-measurement gas in the sealing portion 11, a line 25 for injecting a fresh sealing fluid is provided somewhere in the circulation line. (In the example of FIG. 3, injection into the suction line of the pump). As a result, the same amount 24 of the sealing fluid as the fresh amount flows from the seal portion 11 toward the non-measuring gas.

[0023]

The use of such a sealing device of the present invention in a transparent glass plate for a monitoring window or an optical sensor in a furnace or a flue can prevent the surface of the transparent glass plate from being stained. it can. In instruments such as analyzers, the sampling line is shortened, a pretreatment device for removing dirt contained in the non-measurement gas is not required, maintenance such as periodic inspection is simplified, and high reliability is achieved. Gas analysis with a fast response speed becomes possible. Further, when the sealing fluid circuit by circulation according to the present invention is used, only one power source for blowing and sucking the sealing fluid is required, and the consumption of the sealing fluid can be minimized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an online analysis system that optically measures gas properties according to an embodiment of the present invention.

FIG. 2 is a structural view of a sealing portion for sealing a surface of a transparent glass plate in contact with a non-measurement gas with a fluid in the present embodiment.

FIG. 3 is a configuration diagram of a supply circuit for a sealing fluid.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical online analysis system of gas 2 Non-measurement gas main pipe 3 Non-measurement gas 4 Non-measurement gas branch pipe 10 Sensor part of optical analyzer 11 Seal part for prevention of sensor part contamination 12 Blow-out of sealing fluid Piping 13 Sealing fluid suction pipe 14 Transparent glass plate 20 Sealing fluid supply circuit 21 Sealing fluid circulation pump 22 Sealing fluid return line 23 Sealing fluid air supply line 24 Seal flowing into non-measurement gas system Supply fluid 25 Fresh supply line of sealing fluid 30 Analyzer controller 31 Optical fiber for absorption spectrum transmission 32 Optical fiber for compensation 33 Sealing portion for compensation 41 Sealing fluid outlet 42 Sealing fluid outlet 43 Sealing fluid inlet 44 Fluid suction for sealing Only vessel

Claims (3)

[Claims] 1. A transparent device such as a window for externally monitoring the gas in a furnace or a flue or an analyzer such as an analyzer for measuring the components of a gaseous fluid by an optical method by transmitting light rays such as infrared rays and lasers. In a structure using a glass-like plate, the surface where the non-measurement gas contacts the transparent glass-like plate is sealed by creating a film-like flow with a clean fluid such as air to prevent contamination of the transparent glass-like plate. A sealing device characterized by the above-mentioned. 2. The sealing device according to claim 1, wherein a clean fluid such as air is blown into the surface of the transparent glass plate in a film-like manner at all times, and the blown fluid is For a seal, characterized by smoothing the flow of clean fluid and minimizing the amount of fluid entering the piping by sucking through the suction port installed downstream of the outlet A device that combines a fluid blower and a blower and a suction device. 3. The sealing device according to claim 1, wherein a circulation line is formed as a means for blowing and sucking a fluid for sealing, and a fresh sealing fluid is injected into the line to provide one pump. A sealing fluid supply circuit characterized in that the consumption of the sealing fluid can be minimized.