JPH09281014A - Probe for sampling of exhaust gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a probe by which a desired gas can be sampled surely even under a severe condition such as a high temperature, a strongly acidic or reducing atmosphere or the like, which is excellent in chemical durability and which has a desired mechanical strength even when the probe is long. SOLUTION: The probe 2 which samples a part of an exhaust gas G flowing in a gas flue 1 is constituted of an outer pipe 5 composed of a metal material whose heat resistance, corrosion resistance and workability are excellent, of an inner pipe 6 which is installed so as to be concentric with the outer pipe 5 inside the outer piece and which is composed of a material inert to the gas G at a high temperature and of a filler 7 which is interposed and mounted between the outer pipe 5 and the inner pipe 6, which is inert to the gas G and which is excellent in heat resistance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas collecting probe for collecting a part of combustion exhaust gas discharged from a boiler or the like as a sample gas (hereinafter referred to as "probe").
Simply referred to as a probe).

[0002]

BACKGROUND ART For example, SO ₂ in the combustion exhaust gas discharged from a boiler for burning coal, NO _X, CO _2, C
When continuously analyzing components such as O, it is necessary to sample a part of the combustion exhaust gas and continuously supply this to the gas analyzer as a sample gas. By the way, the exhaust gas has a high temperature of 500 to 700 ° C. and has a considerably strong oxidizing / reducing property. As a material for a probe that collects exhaust gas having such properties, it is required to be heat-resistant and inert to oxidizing and reducing gases, and ceramic, quartz, or aluminum is quite effective.

[0003]

However, ceramics and quartz are vulnerable to mechanical strength, especially to impact, and
There was a defect that the workability was poor, and a long probe could not be formed. Aluminum has a melting point of 650.
The material strength is not always sufficient in the vicinity of ° C and is not necessarily suitable as a single structural material.

By the way, in recent years, due to the need for environmental protection, the pursuit of energy efficiency, and the diversification of electric power demand, the gas turbine power generation plant is becoming larger in size, and the flue is also becoming higher accordingly. Then, as the flue becomes higher, the inner diameter of the flue also becomes larger, and a longer probe is required as the probe. This is because, when performing gas sampling, it is preferable to collect gas from the central portion of the gas.

The present invention has been made in view of the above matters, and an object thereof is to surely obtain a desired gas even under harsh conditions such as a high temperature and a strong oxidizing / reducing atmosphere. It is an object of the present invention to provide a probe having excellent chemical durability and having desired mechanical strength even if it is long.

[0006]

In order to achieve the above object, in the present invention, a probe for collecting a part of exhaust gas flowing through a flue is excellent in heat resistance, corrosion resistance and workability. An outer pipe made of a metallic material, an inner pipe made of a material that is concentric with the outer pipe and is inert to gas at high temperature, and an interposing between the outer pipe and the inner pipe. In addition, the filler is inert to gas and has excellent heat resistance.

In the above probe, the inner pipe may be composed of a plurality of inner pipe members and a relay pipe member for connecting between them, and the inner pipe may be a single aluminum pipe. You may comprise.

With the probe having the above structure, desired gas can be reliably collected even under severe conditions such as high temperature and an atmosphere of strong oxidizing and reducing properties. And even if it is long, it has desired mechanical strength.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment of the present invention. First, in FIG.
Reference numeral 1 is a flue, which is a combustion exhaust gas G as shown by an arrow inside.
Is flowing. Reference numeral 2 is a probe as a gas sampling portion that is inserted and arranged in the flue 1, and its base end side (the right end side in the end) is connected to the gas sampling flow path 4 side via a mounting flange 3.

The probe 2 includes an outer tube 5 and the outer tube 5.
An inner pipe 6 provided concentrically with the inner pipe 6 and these outer pipes 5
And a filler 7 interposed between the inner tube 6 and the inner tube 6. Hereinafter, each member constituting the probe 2 will be described in detail.

The outer tube 5 is made of a metal material having excellent heat resistance, corrosion resistance, and workability, such as stainless steel, and has a length such that even if the flue 1 has a large diameter, it reaches the center of the diameter. Can be formed into Then, the end portion of the outer tube 5 on the opening side is bent inward, and the filling material 7 described later is formed.
Is formed on the holding portion 5a.

The inner pipe 6 is made of a material which is inert to gas at high temperature, and in this embodiment,
It is composed of a plurality of inner pipe members 8 and a relay pipe member 9 for connecting them. That is, the inner tube member 8 is made of, for example, quartz glass, and is configured to have an outer diameter set to an appropriate size with respect to the inner diameter of the outer tube 5. The relay pipe member 9 is made of, for example, quartz glass, is provided with an inner wall portion 9a of an appropriate length that constitutes an inner wall surface of the probe which is flush with the inner wall portion of the inner pipe member 8, and is provided on both sides of the inner wall portion 9a. Connection part 9b inserted between the pipe 5 and the inner pipe member 8
Consists of That is, the inner pipe 6 is configured by connecting the inner pipe members 8 to each other by the relay pipe member 9 by inserting the connecting portion 9b so as to be in close contact with the outer pipe 5 and the inner pipe member 8. ..

The filler 7 is filled so that gas does not flow between the inner pipe 5 and the inner pipe 6, is inert to the gas at a relatively high temperature, and has excellent heat resistance. Material, which in this example is quartz wool. The filling material 7 is provided at the opening-side end of the probe 2 so as to be held by the holding portion 5a. In the other portion of the probe 2, the portion where the relay pipe member 9 is provided, that is, the relay pipe member 9
It is provided at both ends of the connecting portion 9b inserted into the outer tube 5. Further, although not shown, the mounting flange 4 is also provided.

Reference numeral 10 denotes a filler which is interposed between the end portion of the inner pipe member 8 and the end portion of the inner wall portion 9a of the relay pipe member 9 as necessary, and is inert to gas at a relatively high temperature. , Made of a material having excellent heat resistance, for example, quartz wool.

In the probe 2 having the above structure, when gas suction is performed by a suction pump (not shown) provided on the gas sampling flow path 4 side, one of the combustion exhaust gas G flowing in the flue 1 in the direction of the arrow is shown. The part enters the probe 2 through the tip opening of the probe 2. And this combustion exhaust gas G
Flows through the inside of the inner pipe 5 toward the gas sampling flow path 4 side. In this case, the filling material 7 is applied to the opening side end of the outer tube 5 of the probe 2 and both ends of the connecting portion 9b of the relay tube member 9.
Is provided, the amount q of the combustion exhaust gas G flowing between the outer pipe 5 and the inner pipe 6 is almost negligibly smaller than the amount Q of the combustion exhaust gas G flowing inside the inner pipe 5.

In the probe 2 having the above structure, the outer tube 5
Is made of stainless steel having excellent heat resistance, corrosion resistance, and workability, and the inner tube 6 is made of quartz glass which is inert to gas at high temperature. Since quartz wool, which is inert to gas and has excellent heat resistance, is provided as the filler 7, the desired gas can be reliably collected even under severe conditions such as high temperature and strong oxidizing / reducing atmosphere. It is possible to obtain the desired mechanical strength without deteriorating the collected gas. Therefore, it is possible to meet the needs of environmental conservation, pursuit of energy efficiency, and diversification of power demand.

In the above-mentioned embodiment, the inner pipe member 8 and the relay pipe member 9 constituting the inner pipe 6 are made of quartz glass, but instead, they have the same properties as quartz glass. It may be formed of ceramic or pure aluminum.

In particular, when the inner pipe 6 is made of pure aluminum, the inner pipe 6 can be a single cylinder having the same length as the outer pipe 5, as shown in FIG. Member 9
The filling material 7 need not be provided, and the filling material 7 only needs to be provided at two positions, the tip opening portion of the probe 2 and the mounting flange 4, and the configuration of the probe 2 is simplified.

Further, as the fillers 7 and 10, in addition to quartz wool, ceramic wool, alumina fiber type or boronite fiber may be used.

Further, the probe 2 of the present invention can be suitably used for collecting not only combustion exhaust gas but also exhaust gas having high temperature and high chemical property.

[0021]

As described above, in the probe of the present invention, the desired gas can be reliably collected even under severe conditions such as high temperature and an atmosphere of strong oxidizing / reducing property, and the collected gas can be collected. It does not change. Further, even if it is long, it has desired mechanical strength, so that gas sampling can be reliably performed even when the diameter of the flue is large. Therefore, various combustion exhaust gases can be suitably collected.

[Brief description of drawings]

FIG. 1 is a partial cutaway view showing a mounted state of a probe according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the probe in a cutaway manner.

FIG. 3 is a partial cutaway view showing a mounted state of a probe according to another embodiment of the present invention.

[Explanation of symbols]

1 ... Flue, 2 ... Exhaust gas collecting probe, 5 ... Outer tube, 6 ...
Inner pipe, 7 ... Filler, 8 ... Inner pipe member, 9 ... Relay pipe member, G
… Exhaust gas.

Claims (3)

[Claims] 1. A probe for collecting exhaust gas, which is inserted into a flue through which high-temperature exhaust gas flows, wherein the probe for collecting exhaust gas is an outer tube made of a metal material excellent in heat resistance, corrosion resistance, and workability, respectively. An inner tube made of a material that is inert to the gas at high temperature inside the outer tube and is interposed between the outer tube and the inner tube and is inert to the gas. A probe for collecting exhaust gas, characterized in that it is composed of a filler having excellent heat resistance. 2. The exhaust gas collecting probe according to claim 1, wherein the inner pipe comprises a plurality of inner pipe members and a relay pipe member for connecting between them. 3. The exhaust gas collecting probe according to claim 1, wherein the inner tube is made of one aluminum tube.