JPS5912612Y2 - Combustion device for mercury analysis - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a combustion device for burning samples when analyzing mercury contained in various samples by a combustion method.

Conventional mercury analysis methods using the combustion method involve directly burning a sample in air or oxygen, converting the contained mercury into elemental mercury vapor, and quantifying this using atomic absorption spectrometry (
(See Japanese Patent Publication No. 52-48229).

In this combustion method, the organic matter in the sample is directly thermally combusted in oxygen or air flow, so depending on the sample, a local oxygen deficiency may occur during the combustion of the organic matter, resulting in incomplete combustion of the organic matter. There were drawbacks that occurred.

Therefore, recently, as a method to eliminate the above drawbacks,
A method of first pyrolyzing organic matter in an inert gas or oxygen-deficient air, and then completely burning the resulting pyrolysis gas in oxygen to quantitatively convert mercury in the organic matter into elemental mercury vapor. was developed (see Japanese Patent Publication No. 52-11094).

In addition, in order to analyze the mercury contained in the atmosphere, the present inventor filled a cartridge-type mercury collection tube with activated carbon, sucked air into the collection tube, and analyzed the mercury and mercury contained in the air. Compounds are collected, this collection tube is placed in a combustion furnace, the mercury adsorbed on activated carbon is expelled, the organic matter is combusted, the mercury is converted to elemental mercury vapor, and the mercury is sent to the analysis system for measurement. developed a method to do so.

As described above, although the above-mentioned combustion methods have been developed, there is no combustion apparatus that can be used to carry out all of these methods, and the development of one is desired.

Therefore, the purpose of the present invention is to provide a combustion apparatus for mercury analysis that can be applied to the implementation of any of the above methods. (b) a primary processing section configured to accommodate a sample tray or a cartridge-type mercury collection tube, etc. in a manner that can be freely taken out and removed, and equipped with a heat source on the outer periphery; (b) connected in series to the front end of the primary processing section; , a secondary processing section which is filled with a refractory filling and has a communication port connected to the analysis system at its tip, and is equipped with a heat source on the outer periphery; (c) a proximal opening of the primary processing section; A sealing means that can be opened and closed freely; (2) A pair of three-way switching paths are provided above and below the plug fitted in the socket, and the socket has switching ports formed above and below that correspond to the switching paths. By providing a pair of three-way cocks, two three-way cocks are integrally formed, and the socket is dominated by the upper and lower switching ports and one inlet port, and the The switching port on the lower side is connected to an oxygen introduction pipe leading to the secondary processing section, and the other outlet port on the switching port side connected to the oxygen introduction pipe is connected to a gas introduction port communicating with the primary processing section. At the same time, the outlet port connected to the gas inlet is connected to the remaining one of the upper or lower outlet ports, and the inlet port on the switching port side connected to the oxygen inlet pipe is connected to the valve. etc., and connect the other switching port side and the inlet port to an inert gas supply source, and by rotating the plug, the oxygen gas supplied from both the gas supply sources and This device is characterized in that it is configured to switch the inert gas flow path.

Hereinafter, the present invention will be explained in detail based on the illustrated embodiments.

In the figure, 1 is the primary processing section, which is made of quartz tube etc.
A heat source 2 such as a heating wire is provided on the outer periphery.

The base end of the primary processing section 1 has an opening 3 serving as an entrance/exit.
A lid 4 is removably fitted into the opening 3 to seal it tightly.

In the embodiment, a packing 5 made of silicone rubber or the like is fitted to the edge of the opening, and a lid 4 is fitted to the top of the packing 5 to maintain airtightness. Other configurations may be adopted.

As will be described later, the diameter and length of the primary processing section 1 are determined so that a sample tray or a cartridge-type mercury collection tube can be accommodated therein in and out.

Reference numeral 6 denotes a gas inlet provided on the outer circumferential wall on the proximal side of the primary processing section 1 .

7 is a secondary processing section connected in series to the front end of the primary processing section;
Made of quartz tube or the like, the inside of the secondary processing section 7 is filled with granular alumina, quartz wool, or other refractory filler 8, and a communication port 9 connected to the analysis system is formed at the tip. There is.

Further, a heat source 10 such as a heating wire is arranged on the outer periphery of the secondary processing section 7 .

Reference numeral 11 denotes an oxygen introduction tube, the distal end outlet 11 a of the tube 11 reaches into the secondary processing section 7 , and the proximal end inlet 11 b projects outside from the primary processing section 1 .

Reference numeral 12 denotes a protrusion provided at the boundary between the primary processing section 1 and the secondary processing section 7 in order to stably hold the filler 8 in the secondary processing section 7.

13 is a three-way cock, as shown in detail in FIG. Switching ports 18 and 19 are provided in correspondence with channels 16 and 17, and two three-way ports 1 are provided.
3a and 13b are integrally formed.

The upper and lower switching ports 18 and 19 of the socket 14 are two outlet ports 18a, 18b and 19a, 19b and one inlet port 18C and 19, respectively.
It is formed by C.

One of the above-mentioned upper or lower switching ports 18 or 19, 18a (or 19a), is connected to the oxygen introduction pipe 11 leading to the secondary processing section 7, and
The other output port H8b (or 19b) on the switching port side connected to the oxygen introduction pipe 11 is connected to the gas introduction port communicating with the primary processing section 1, and the outlet port connected to the gas introduction port is on the upper side. Alternatively, it is connected to the remaining outlet port H9a (or 18a) of the lower outlet ports. The outlet port H9a on one side of the lower three-way socket 13b is connected to the gas introduction pipe 6 through the connecting pipe 21, and the outlet port 19a is connected to the upper three-way socket 13 through the connecting pipe 20. It is connected to the outlet port 18b on the other side of a.

Further, in the embodiment, a Y-shaped pipe is used as the connecting pipe 21, and the outlet ports 19a and 18b are connected to the gas inlet 6.

In addition, in the above case, the lower three-way pot 13b
The outlet port 19a on one side of the tank is connected to the oxygen introduction pipe 11, and the outlet port 18a of the three-way socket 13a on the upper side and the outlet port 19b of the three-way socket 13b on the lower side are connected to the gas inlet port 6. However, in principle they are the same.

Then, the inlet port on the switching port side connected to the oxygen introduction pipe 11 is connected to an oxygen gas supply source via a valve or the like, and the inlet port on the other switching port side is connected to an inert gas supply source, and the plug 15 is configured to switch the flow paths of oxygen gas and inert gas supplied from both gas supply sources, and in the embodiment, the inlet port 18C on the switching port 18 side on the upper side is The valves 22 and 23 are connected to the oxygen gas supply source and the inlet port H9C on the lower switching port 19 side to the inert gas supply source.
(See Figure 1).

Note that nitrogen, helium, argon, etc. are used as the inert gas.

FIG. 5 shows an example of a sample tray 24, which is shaped like a trough-like dish.

FIG. 6 shows an example of a cartridge-type mercury collection tube 25, which includes an air intake port 26 and an air outlet 27.
The inside is filled with activated carbon 28 as a mercury adsorbent.

In the figure, 29 is a plug detachably fitted into the air intake port 26, and 30 is a mouth tube inserted through the plug 29.

In FIG. 1, reference numeral 31 denotes a neutralization section connected to the communication port 9 of the secondary processing section 7, filled with a neutralizing agent, and equipped with a heat source 32.

33 is a cooler, 34 is a dehumidifier, and 35 is a mercury trapping section filled with a mercury trapping agent, which is equipped with a heat source 36.

The present invention is structured as described above, and an example of its use will be explained next.

Usage example 1 As shown in the second diagram, the sample S is placed in the sample tray 24, placed in the primary processing section 1, and the lid 4 is fitted into the opening 3, and the sample Part 7 is connected to electric heat source 2
, 10, respectively.

This heating temperature is in the range of 200 to 1000°C, preferably 300 to 800°C in the primary processing section 1, and 500 to 1200°C in the secondary processing part 7,
Preferably the temperature is in the range of 700 to 900°C.

Then, operate the three-way Kotoku 13 to open the upper Kotoku 13.
The inlet port 18C of the lower part a is connected to the outlet port 18a, and the inlet port 19C of the lower part 13b is connected to the outlet port 19a.

This operation can be performed simultaneously by rotating the plug 15.

Therefore, valve 22. 23 (see FIG. 1) is opened, and oxygen is introduced into the secondary processing section 7, and an inert gas such as nitrogen, helium, argon, etc. is introduced into the primary processing section 1.

As a result, the sample S is thermally decomposed and gasified in the primary processing section 1, and this pyrolysis gas is guided into the secondary processing section 7 by the atmospheric gas flow, where it is combined with oxygen from the oxygen introduction tube 11. The organic matter in the gas is completely combusted.

During this complete combustion process, the mercury contained in the sample is quantitatively thermally dissociated into elemental mercury vapor, which passes through the communication port 9, the neutralization section 31, the cooler 33, and the dehumidifier 34 (as described above). The raw gas produced by the combustion is removed during this transfer process) and sent to the mercury trapping section 35, where it comes into contact with a mercury trapping agent, and the mercury in the gas is trapped as an amalgam.

The mercury captured by the mercury trapping agent is then heated by the mercury, liberates it again, and is guided to an atomic absorption spectrometer or the like and quantified.

In this method, as described above, pyrolysis gas from organic substances quantitatively generated by heating in an oxygen-deficient state is mixed with an excess amount of oxygen introduced into the secondary treatment section 7, heated, and completely combusted. Because of this, it is particularly suitable for burning samples with a large amount of organic matter or samples containing a large amount of organic matter.

Usage Example 2 Depending on the type of sample, some organic substances can be completely combusted by direct combustion in oxygen without using an inert gas as described above.

In such a case, as in usage example 1, the sample tray 24 containing the sample S is housed in the primary processing section 1, the lid 4 is fitted, and the primary processing section 1 and the secondary processing section are closed in the same manner as described above. The processing section 7 is heated, and the plug 15 of the three-way plug 13 is rotated 180 degrees from the state shown in FIG.
The inlet port 18C of 3a is connected to the outlet port 18b.

Then, only the valve 22 on the oxygen side is opened to introduce oxygen into the primary processing section 1.

Therefore, the sample S is burned in the primary treatment section 1, and the mercury contained in the sample is thermally dissociated into elemental mercury vapor, which is sent to the secondary treatment section 7 together with the combustion gas. After that, as in the case of use example 1, the gas is sent to the analysis system through the communication port 9 and measured.

This method is suitable for water samples, samples with little organic matter such as minerals,
Alternatively, it is suitable for heating vaporization of organic samples with a small amount of sample.

Usage Example 3 This usage example uses a cartridge type mercury collection tube 25. The collection tube 25 is filled with activated carbon 28, and air is sucked into the collection tube 25 using an air pump or the like to remove the air in the air. Mercury is collected with activated carbon 28, and this collection tube 25 is housed in the primary processing section 1 as shown in the eighth figure.

In order to accommodate this, a lid 4 or the like having a fitting hole 4a for tightly fitting and supporting the collection tube 25 is provided separately from the lid 4 described above, and the hole 4a of the lid 4 is inserted into the hole 4a. The air intake port 26 side of the collection tube 25 is inserted and supported, and the collection tube 25 is accommodated in the primary processing section 1 with the air outlet 27 located on the secondary processing section 7 side.

Then, the inlet port 18C of the upper pot 13a is connected to the outlet port 18b, and the artificial port H9C of the lower pot 13b is connected to the outlet port 19b.
This output port 19b is connected to the air intake port 26 of the collection pipe 25 through a connecting pipe 37, and the valves 22.23 are opened to supply oxygen to the primary processing section 1, nitrogen, argon, and nitrogen to the collection pipe 25.
A carrier gas such as helium is introduced, and the primary processing section 1 and the secondary processing section 7 are heated.

As a result, the mercury adsorbed on the activated carbon 28 is expelled from the air outlet 27 and sent to the secondary treatment section 7, where the organic matter is completely burned by oxygen from the inlet 6 and the mercury is removed. The mercury vapor is converted into elemental mercury vapor and sent to the analysis system through the communication port 9, where it is measured.

Since the present invention is constructed as described above, the sample in the primary treatment section can be directly combusted in that section, and the sample is once thermally decomposed in the primary treatment section, and the pyrolysis gas is transferred to the secondary treatment section. The mercury contained in the atmosphere can be collected using a cartridge-type mercury collection tube and used for combustion in this analysis, so it can be used for mercury analysis. The optimum combustion device can be obtained.

In particular, the present invention provides a pair of upper and lower switching paths in three directions on the plug fitted into the socket, and a pair of switching ports arranged above and below that correspond to the switching paths in the socket. The socket is provided with a three-way cock formed by integrating two three-way cocks, and the upper and lower switching ports of the socket are respectively formed by two outlet ports and one inlet port, and the upper and lower switching ports are formed by two outlet ports and one inlet port, respectively. One outlet port of the switching ports on the lower side is connected to an oxygen introduction pipe leading to the secondary processing section, and the other outlet port on the side of the exit port is connected to a gas introduction port communicating with the primary processing section. At the same time, the outlet port is connected to the remaining one of the upper or lower outlet ports, and the inlet port on the switching port side connected to the oxygen introduction pipe is injected with oxygen via a valve or the like. A flow path for oxygen gas and inert gas supplied from both gas supply sources by connecting the plug to a gas supply source and connecting the inlet port on the other switching port side to an inert gas supply source and rotating the plug. It is arranged to switch the

Therefore, the gas flow path can be easily and quickly changed by simply rotating the plug, so the flow path of the supplied gas can be selected according to the type of material, etc., and the combustion method suitable for the sample can be adopted. be able to.

[Brief explanation of drawings]

Fig. 1 is a schematic layout diagram of a mercury analyzer using a combustion device according to the present invention, Fig. 2 is a longitudinal sectional view of the combustion device according to the present invention, and Fig. 3 is a three-sided view of the combustion device used in the combustion device according to the present invention. FIG. 4 is an exploded perspective view showing an example of a cock; FIG. 4 is an enlarged sectional view taken along line 1-1 in FIG. 2; FIG. 5 is a perspective view showing an example of a sample tray; FIG. 6 is an example of a cartridge-type mercury collection tube. 7 and 8 are explanatory diagrams showing different usage conditions, respectively. 1...Primary treatment section, 2...Heat source, 3.
...Opening, 4...Lid, 6...
・Gas inlet, 7...Secondary treatment section, 8...
・・Fireproof secondary filling, 9・・Communication port, 10・・・・
...Heat source, 11...Oxygen introduction pipe, 13...
...Three-way cock, 13 a, 13 b...
Three-way cock, 14...Socket, 15...
...Plug, 16,7...Switching path, 18.19
...Switching port}, 18a, 18b, 9a,
19b...Exit port, 18C, 19C
...... Entrance port, 20, 21... Connecting pipe, 22. 23... Valve etc., 24...
...Sample tray, 25...Cartridge type mercury collection tube.

Claims (1)

[Scope of utility model registration request] (a) A primary processing section 1 whose base end is opened to serve as an entrance and exit, which is shaped so that a sample tray or a cartridge-type mercury collection tube can be freely taken in and out, and which is equipped with a heat source on the outer periphery. , (b) connected in series to the front end of the primary processing section 1, filled with a refractory filling inside, having a communication port connected to the analysis system at the tip, and equipped with a heat source on the outer periphery. secondary processing section 7, (c) sealing means for opening and closing the proximal opening of primary processing section 1, and (2) connecting the three-way switching paths 16 and 17 up and down to the plug 15 fitted in the socket 14. A second three-way socket 13a is provided by providing a pair of switching ports 18 and 19 vertically in the socket 14, which are shaped to correspond to the switching paths 16 and 17.
and 13b are integrally formed and provided with a certain three-way socket 13, and the upper and lower switching ports 18 of the socket 14
and 19 are each formed by two outlet ports 18a, 18b and ul9a, 19b and one inlet port 18C and 19C, one of said upper or lower switching ports 18 or 19 outlet port 18 of
a (or 19a) is the oxygen introduction pipe 1 leading to the secondary processing section 7
1, and the other output port N8b (or 19b) on the switching port side connected to the oxygen introduction pipe 11 is connected to a gas introduction port communicating with the primary processing section 1, and is connected to the gas introduction port. The outlet port used for consecutive days is connected to the remaining outlet port H9a (or 18a) of the upper or lower outlet port, and the human outlet port H8C (or 19C) to an oxygen gas supply source via a valve or the like, and connect the inlet port 19C (or 18C) on the other switching port side to an inert gas supply source, and rotate the graph 15 to A combustion apparatus for mercury analysis, characterized in that the flow path of oxygen gas and inert gas supplied from a gas supply source is switched.