JP2001083054A - Exhaust gas sample collecting method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust gas sample collecting method and device, capable moreover of accurately and simply capturing without losses even components that are easily adsorbed by condensation moisture. SOLUTION: In an exhaust gas sample collecting method, a sample gas of exhaust gases collected from inside a duct 11 is captured by passing the sample gas through an adsorption bottle 1 with both a container 3, in which an adsorbent 2 is housed and an inlet tube 4 for introducing a sample gas to the adsorbent 2. At the introdiction of a sample gas through the adsorbent 2, the inlet tube 4 is inserted airtightly into a heat-insulated or heated conduit 16. After the introduction of the sample gas to the adsorbent 2 is completed, the inside of the inlet tube 4 which is pulled out of the conduit 16 is cleaned by a cleaning liquid, and the cleaning liquid is added to make the volume of the adsorbent 2 predetermined amount and used as a sample solution for analysis.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas sampling method and an exhaust gas sampling apparatus, and more particularly, to a method for accurately and accurately absorbing components such as hydrogen chloride and sulfur oxide which are easily adsorbed to dew condensation water. The present invention relates to a method and an apparatus for collecting an exhaust gas sample that can be collected in an exhaust gas.

[0002]

2. Description of the Related Art In the case of manual analysis of exhaust gas, a sample gas is introduced into an absorption bottle containing an absorption solution, collected, and the absorption solution having absorbed a component to be analyzed is used as a sample solution for analysis. (Refer to Japanese Industrial Standard K0095-1994 "Exhaust gas sampling method").

[0003] As shown in FIG.
And an inlet pipe 4 for introducing exhaust gas into the absorbing liquid 2. A glass ball filter 5 and the like are provided at one end of the inlet pipe 4 inserted into the absorbing liquid 2 so that publishing to the absorbing liquid 2 can be performed efficiently. A drying tube, a suction pump, a gas meter, and the like are sequentially connected to the end of the outlet 6 of the absorption bottle 1 (all are not shown).

[0004] A filter 13 is attached to the tip of a collection pipe 12 for collecting exhaust gas from the duct 11, and is inserted into the duct 11 from a collection port 15 provided in the duct wall 14.

[0005] The collection tube 12 and the absorption bottle 1 are connected by a conduit 16. Reference numeral 17 denotes a connection portion between the collection tube 12 and the conduit 16. This conduit 16 is usually placed in a heat retaining area 21 which is heated or kept warm by a heater or the like together with the sampling pipe 12. This is performed in order to prevent moisture or gas components having a high dew point in the exhaust gas from condensing in the conduit 16 or freezing the condensed water.

Conventionally, the conduit 16 and the inlet pipe 4 of the absorption bottle 1 have been connected to each other by using a spherical joint 22 outside the heat retaining area 21. The spherical ground joint 22 can be separated into a joint 22a on the absorption bottle 1 side and a joint 22b on the conduit 16 side, and these can be airtightly connected by bringing them into close contact.

A three-way cock 23 is attached in the vicinity of the outlet of the conduit 16 and a bypass 24 is connected. The bypass 24 is appropriately provided with a washing bottle and the like, and is connected to a drying tube, a suction pump, a gas meter and the like of the previous operation via a three-way cock on the downstream side of the absorption bottle 1.

To collect the sample gas in the absorption bottle 1, first, the three-way cock 23 is turned to the bypass 24 side, and the sample gas flows through the bypass 24 to a drying tube, a suction pump, a gas meter, and the like. The portion from the sampling tube 12 to the three-way cock 23 is replaced with the sample gas. Thereafter, the three-way cock 23 is turned to the inlet pipe 4 side, and the sample gas is ventilated to the absorption bottle 1. Then, after a predetermined amount of the sample gas is ventilated, the connection on the outlet 6 side is disconnected, and the spherical joint 22 is separated into the joint 22a and the joint 22b, so that the connection between the conduit 16 and the absorption bottle 1 is disconnected.

The absorption liquid 2 is once transferred to a flask after being taken into a beaker. At this time, the joint 22a, the inlet pipe 4,
The water that has washed the inside of the container 3 is also added to the absorbing solution, and finally the fixed volume in the flask becomes a sample solution for analysis. As described above, not only the container 3 but also the joint 22a and the inlet pipe 4 are cleaned because the sample gas is cooled and dewed when it comes out of the heat retaining region 21, and the component to be analyzed is adsorbed to the dew water. It is. Therefore, the cause of the negative error at the time of collection is eliminated by washing and recovering it.

[0010]

As described above, conventional measures have been taken with respect to the adsorption of an analyte to dew water, but the present inventor has found that this measure is inadequate for eliminating negative error factors. I learned from experience that I could not say that. That is, when the sample gas goes out of the heat retaining region 21, it is rapidly cooled by the outside air. Therefore, the joint 22b
Also, dew condensation occurs in the conduit 16 near the joint 22b. And since the dew water generated in this part which is cut off from the absorption bottle 1 cannot be washed, the analysis target component adsorbed thereon cannot be recovered.

Further, the spherical grinding joint 22 is disposed immediately adjacent to the heat retaining region 21. When the air is separated into the joint 22a and the joint 22b after the ventilation to the absorption bottle 1, the outside air flows into the conduit 16 from the joint 22b. And the sample gas remaining in the conduit is directly cooled, so that dew condensation occurs even in the heat retaining area 21. In this state, the absorption bottle 1 was used for the next analysis.
Are connected again at the spherical joint 22.
Analyte components are adsorbed to dew water generated in a wide range that cannot be washed and recovered.

If the heat retaining area 21 is extended to the spherical joint 22 and the inlet pipe 4 near the spherical joint 22, the above problem can be solved. However, a heater and a heat insulating material are wound around the heat insulating area 21, and these are to be removed each time the joint is connected or disconnected, which is very complicated and impractical.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides an exhaust gas sampling method and a sampling apparatus capable of accurately and easily collecting a component easily adsorbed on dew condensation water without loss. As an issue.

[0014]

According to the present invention, in order to solve the above-mentioned problems, a sample gas obtained by collecting exhaust gas in a duct is provided.
In the exhaust gas sampling method in which the sample gas is ventilated and collected through an absorption bottle having a vessel containing the absorbing solution and an inlet pipe for introducing the sample gas into the absorbing solution, when the sample gas is introduced into the absorbing solution, the sample is kept warm or heated. After the inlet pipe is hermetically inserted into the drawn conduit, and after the introduction of the sample gas into the absorbing liquid is completed, the inside of the inlet pipe pulled out of the conduit is washed with a cleaning liquid, and the cleaning liquid is washed with the absorbing liquid. To provide a method for collecting exhaust gas.

[0015] The exhaust gas sample is collected by passing the sample gas obtained by collecting the exhaust gas in the duct through an absorption bottle having a container containing the absorbing solution and an inlet pipe for introducing the sample gas into the absorbing solution. In the apparatus, there is provided an exhaust gas sampling apparatus, characterized in that the inlet pipe is hermetically and removably inserted into a heated or heated conduit.

As described above, if the inlet pipe is inserted into the conduit, that is, if the inlet pipe and the conduit have a double-pipe structure, the inlet pipe can be extended into the heat insulation area, and the measurement adsorbed on the dew water can be performed. The target component can be reliably washed and recovered. In addition, connection and detachment are also performed by insertion and withdrawal, and these can be easily performed without removing a heat insulating material or the like from outside the heat insulating region.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. The same components as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 1, reference numeral 31 denotes a rubber tube, and 32 denotes a ring-shaped seal member. In the present embodiment, the rubber tube 3 is connected to the conduit 16 from the outlet side of the heat retaining area 21.
1 is covered, and one end of the rubber tube 31
The other end is housed in a heat retaining area outside of the heat sink 1. Then, the inlet tube 4 can be inserted from the rubber tube 31 into the heat-resistant glass conduit 16 having a larger diameter. The inlet pipe 4 is made of heat-resistant glass, and a silicone rubber sealing member 32 is fixedly mounted near the tip thereof. The sealing member 32 keeps the space between the conduit 16 and the inlet pipe 4 airtight. ing.

As in the prior art shown in FIG. 3, the outlet 6 and the bypass 24 are connected to a drying pipe, a suction pump, a gas meter and the like via a three-way cock on the downstream side. This will be described more specifically with reference to FIG. Downstream of the outlet 6 of the absorption bottle 1 of the sampling device 100, another absorption bottle 41 is connected via a spherical mating joint 42. Further, a spherical grinding joint 43 is also provided downstream of the absorption bottle 41. Cleaning bottles 52 and 53 are interposed in the bypass 24. In addition, before and after the cleaning bottles 52 and 53, spherical surface fittings (not shown) are appropriately interposed, so that these cleaning bottles can be easily removed from the bypass 24.

A three-way cock 54 is provided on the downstream side of the absorption bottle 51 and the washing bottle 53, and the sample gas that has passed through either the absorption bottle side or the bypass washing bottle side is fed to a mercury manometer 55 further downstream. It can be ventilated. After that, the sample gas is supplied to the drying tube 56, the suction pump 57,
The gas is discharged through a gas meter 58. 6
Reference numerals 1 and 62 denote flow control cocks.

When collecting an exhaust gas sample in this embodiment,
The following operations are performed. First, the suction pump 57 is operated, the three-way cocks 23 and 54 are set to the bypass 24 side, and the exhaust gas is sucked through the bypass 24. At this time, the absorbing liquid is put in the cleaning bottles 52 and 53 so that the exhaust gas sample is not released to the outside air as it is. When the gas from the sampling tube 12 to the three-way cock 23 is sufficiently replaced with the sample gas, the suction pump 57 is stopped, the three-way cocks 23 and 54 are switched to the absorption bottles 1 and 41, and the indication of the gas meter 58 at that time is recorded. I do.

Thereafter, the sample gas is passed through the absorption bottles 1 and 41 by operating the suction pump 57. At this time, the sample gas is sampled at a predetermined flow rate by adjusting the flow rate adjusting cocks 61 and 62. Then, after sampling a predetermined amount of the sample gas, the suction pump 57 is stopped, the three-way cocks 23 and 54 are closed, and the instruction of the gas meter 58 is read. Gas meter 5 at this time
The difference between the instruction of 8 and the previously recorded instruction is the gas amount measured by the gas meter. In addition, in order to obtain the gas amount converted into the standard state from the gas amount measured by the gas meter, the temperature and the pressure are measured.

After the suction of the sample gas is completed, the spherical joints 42 and 43 are removed, and the inlet pipe 4 is connected to the sealing member 3.
2 and the absorbent bottle 1 and the absorbent bottle 41 are removed from the collection device 100. Then, the absorbing solution 2 is once taken into a beaker together with the absorbing solution in the absorbing bottle 41 and then transferred to the flask. At this time, the entire inside of the sample gas passage from the front end side of the inlet pipe 4 inserted into the conduit 16 to the absorption bottle 41 via the container 3 of the absorption bottle 1 and the spherical mating joint 42 is made of water. It is washed and the washing water is also added to the absorbing solution. The final volume of the flask is a sample solution for analysis.

At this time, since the inlet pipe 4 is inserted into the heat insulation area 21, the components to be analyzed adsorbed on the condensed water generated outside the heat insulation area 21 are washed out together with the condensed water and collected reliably. be able to.

Further, when a new exhaust gas sample is to be collected, the absorption bottles 1 and 41 containing a new absorbing liquid may be attached to the sampling device 100. At this time, the inlet pipe 4
Can be inserted into the inside of the conduit 16 from the place where the tip of the rubber tube 31 is extended and expanded together with the sealing member 32. Then, if the spherical grinding joints 42 and 43 are connected, the sampling device 100 is assembled in the original state shown in FIGS. 1 and 2, so that the sampling of the sample gas can be repeated by repeating the above steps.

While the inlet pipe 4 is being pulled out, outside air flows into the conduit 16 and some dew condensation occurs near the outlet thereof. If the pipe 4 is inserted farther than the dew point, the dew point does not exist in the gas flow path at the time of the next sample gas sampling, and there is no problem of being adsorbed by the dew point generated at the time of removal. . Also, the rubber tube 31
Since the outside air inflow is restricted by the presence of the water, the amount of dew water generated can be suppressed to a small amount.

In the present embodiment, as a mode in which the inlet pipe 4 is inserted into the conduit 16 in a gas-tight and removably insertable manner, the heat-resistant glass inlet pipe 4 having a sealing member 32 attached to the tip thereof is replaced with a heat-resistant glass having a larger diameter. Although it was made into the mode inserted in the conduit 16 made from a product, the mode of insertion is not specifically limited. For example, the outside of the inlet tube 4 and the inside of the conduit 16 in the insertion portion can be made of frosted glass. In addition, conduit 16
If the inner pipe and the inlet pipe 4 are made of Teflon (trade name) tube having the same inner diameter of the former and the outer diameter of the latter, by applying grease to the outside of the inlet pipe 4, airtight and easy insertion and removal can be achieved. Further, a ring-shaped packing member is fixedly mounted in the conduit 16, and inside the packing member,
An inlet pipe 4 made of glass, metal, or the like can be inserted.

In this embodiment, two absorption bottles are arranged. However, if one absorption bottle can sufficiently absorb the target component, only one absorption bottle may be used. Similarly, bypass 2
The number of washing bottles to be interposed in 4 is also arbitrary.

It is not always necessary to integrally form the inlet pipe 4 from the tip end portion inserted into the conduit 16 to the ball filter 5. A suitable joint or the like may be interposed. The type of the absorption bottle is not particularly limited. In addition to those having a ball filter at the end, various types such as those having one end of an inlet pipe opened in the absorption liquid as it is and those passing through a glass filter plate can be used. Can be used.

In the present embodiment, the suction pump 57 and the gas meter 58 are used to vent a certain amount of the sample gas into the absorbing solution. It may be arranged downstream of the absorption bottle 1.

[0030]

According to the exhaust gas sampling method and the sampling apparatus according to the present invention, the components to be analyzed adsorbed on the dew water can be reliably recovered, so that the exhaust gas can be accurately analyzed.
In particular, it becomes possible to accurately perform a manual analysis of a component easily adsorbed on dew condensation water, for example, hydrogen chloride or sulfur oxide, which is liable to generate a negative error. In addition, since replacement of the absorption bottle can be performed without removing the heat insulating material, heater, etc.,
The operation is simple, and daily manual analysis can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a main part configuration diagram of an exhaust gas sampling apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing an overall configuration of an exhaust gas sampling device according to an embodiment of the present invention.

FIG. 3 is a configuration diagram of a main part of a sample collection device according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Absorption bottle 2 Absorbing liquid 3 Container 4 Inlet pipe 11 Duct 16 Conduit 21 Heat insulation area

Claims (2)

[Claims] 1. An exhaust gas sampling system in which a sample gas from which exhaust gas is collected in a duct is collected by passing the sample gas through an absorption bottle having a container containing an absorbing solution and an inlet pipe for introducing the sample gas into the absorbing solution. In the method, when introducing the sample gas into the absorbing solution, the inlet tube is hermetically inserted into a heated or heated conduit, and after the introduction of the sample gas into the absorbing solution is completed,
An exhaust gas sampling method, comprising washing the inside of the inlet pipe withdrawn from the inside of the conduit with a washing liquid, and adding the washing liquid to the absorbing liquid. 2. An exhaust gas sampling method in which a sample gas from which exhaust gas is collected in a duct is collected by passing the sample gas through an absorption bottle having a container containing an absorbing solution and an inlet pipe for introducing the sample gas into the absorbing solution. In the apparatus, the inlet pipe is hermetically and removably inserted into a heated or heated conduit so as to be removable.