WO2019078265A1

WO2019078265A1 - Analysis device and total organic carbon measurement device

Info

Publication number: WO2019078265A1
Application number: PCT/JP2018/038692
Authority: WO
Inventors: 中森　明興
Original assignee: 株式会社島津製作所
Priority date: 2017-10-18
Filing date: 2018-10-17
Publication date: 2019-04-25
Also published as: JPWO2019078265A1; JP6879377B2

Abstract

The present invention pertains to an analysis device provided with a heating furnace for heating a combustion tube into which a sample is introduced and thereby combusting the sample and performing oxidation decomposition. A small tube part is provided to an outlet of the combustion tube. The heating furnace has a housing. A hole part passing through the housing of the heating furnace is provided in a lower portion of the housing. The diameter of the hole part is greater than the outside diameter of the combustion tube. A sealing material that seals the hole part is provided in the hole part. A hole for the insertion of the small tube part of the combustion tube is provided in the sealing material.

Description

Analyzer and total organic carbon measurement device

The present invention is an analyzer equipped with a heating furnace for heating a combustion tube into which a sample is introduced, thereby burning and oxidizing the sample, and an all-organic carbon measuring apparatus equipped with the analyzer. About.

For example, measurement of total organic carbon (TOC) and total nitrogen (TN) is one of the important items in the survey of water quality such as sewage, river water, and factory drainage. As a water quality analyzer, measure the total organic carbon measuring device (TOC meter) of combustion catalytic oxidation type that measures the total organic carbon (TOC) contained in the sample (water) and the total nitrogen (TN) Total nitrogen measuring devices (TN meters) are known. Also, analyzers capable of measuring both total organic carbon and total nitrogen are known. In these water quality analyzers, the collected sample is introduced into the combustion unit, and in the all-organic carbon measuring device, the carbon component in the sample is burned, oxidized and decomposed to be carbon dioxide, and in the total nitrogen measuring device, the sample is The nitrogen components of the catalyst are burned and oxidized to be converted to nitrogen oxide (NO), and a gas containing them is introduced into the cell of the detection unit.

The detection unit of the water quality analyzer will be described. In the total organic carbon measurement apparatus, the absorbance derived from the carbon dioxide concentration in the gas introduced to the cell is measured. In the total nitrogen measuring device, the amount of luminescence derived from the nitrogen oxide concentration in the gas led to the cell is measured. By determining the peak area value of the detection signal data obtained by these measurements, total organic carbon or total nitrogen in the sample is quantified. That is, in order to quantify total organic carbon or total nitrogen, a calibration curve indicating the relationship between total organic carbon or total nitrogen and the area value of the peak of the detection signal data is prepared in advance, and the measured is measured. Based on the calibration curve, total organic carbon or total nitrogen can be quantified from the area value of the peak according to the signal data (see Patent Document 1).

Usually, a combustion unit (combustion pipe) into which the collected sample is introduced is disposed in the heating furnace. The sample is heated to 680 ° C. by a heating furnace in the presence of abundant purified air in a combustion tube filled with a platinum catalyst.
The outer periphery of the heating furnace may be surrounded by an outer wall of a heat insulating material mainly composed of ceramic fibers or alumina fibers so that heating of the combustion tube by the heating furnace is performed efficiently and uniformly (Patent Document 2) reference).

JP 2012-137377 JP, 2012-137459, A

Since the outer periphery of the heating furnace is surrounded by the outer wall made of a heat insulating material, heat can be prevented from escaping from the outer periphery of the heating furnace. However, it is difficult to surround the upper and lower portions of the casing of the heating furnace with a heat insulating material for convenience of being disposed in the heating furnace with the upper and lower portions in the axial direction of the combustion tube protruding from the heating furnace. Therefore, heat was easily released from these parts, and it was inevitable that the upper and lower parts in the furnace had a lower temperature than the central part.

Here, the heat insulating performance can be maintained relatively by covering the upper part of the casing of the heating furnace with a ceramic member (a lid or the like) having a hole through which the combustion tube main body can be inserted. However, in the lower part of the casing of the heating furnace, it is difficult to install such a member. Therefore, there is a need to solve the problem that the heat escapes from the gap between the hole (larger than the outer diameter of the combustion tube main body) and the outlet of the combustion tube conventionally provided in the lower part of the casing of the heating furnace The
In particular, the outlet portion of the combustion tube is generally a thin tube portion for catalyst holding and piping connection, which causes a large gap with the hole.
As described above, the lower portion of the casing of the heating furnace is provided with a hole of a larger diameter than the outer diameter of the combustion tube main body. The reason for this is to be able to be pulled out when the combustion tube main body is broken inside the furnace. Therefore, this structure can not be avoided for maintenance.

Therefore, in order to efficiently and uniformly heat the combustion tube by the heating furnace, for example, in the gap between the hole in the lower part of the casing of the heating furnace and the combustion tube (specifically, the thin tube portion provided at the outlet) A work of packing cotton-like heat insulating material such as quartz wool is performed from below the heating furnace. If the heat insulation of the heating furnace is insufficient, the catalyst temperature in the combustion tube will not be stable, the measured values will vary, and the performance of the analyzer will be adversely affected.
The present invention has been made to solve such problems in the prior art.

In order to solve the above-mentioned subject, the analyzer concerning the 1st mode of the present invention is provided with the heating furnace which heats a combustion pipe, in order to burn and oxidize and decompose the sample introduced into the combustion pipe, In the lower part of the case of the furnace, the case is penetrated and a hole with a diameter larger than the outer diameter of the combustion tube main body is bored, and heat insulation having a hole into which the thin tube part at the outlet of the combustion tube main body is inserted A sealing member made of a material is attached to a hole in a lower portion of a casing of a heating furnace to seal the flow of heat.
Although an appropriate thing can be applied as a material of a heat insulating material, ceramic-made is suitable. Moreover, as a shape of a sealing member, the cylindrical body of a diameter substantially the same as the diameter of the hole of the housing | casing lower part of a heating furnace is suitable.

In the first aspect, the seal member may be provided with flanges having a diameter smaller than the diameter of the hole and larger than the diameter of the hole at both ends of the body longer than the lower housing thickness of the heating furnace. The portion may have a hole into which the thin tube portion of the outlet portion of the combustion tube main body is inserted, and a tapered portion may be formed from the upper flange portion toward the body portion, and the seal member is in the axial direction May be divided into at least two.

In this embodiment, the flange portion above the seal member has a function to prevent the seal member from falling from the hole when the seal member is mounted in the hole formed in the lower portion of the casing of the heating furnace. Have. In addition, the fact that the seal member is divided in the axial direction allows the seal member (upper flange portion) having a flange portion with a diameter larger than the diameter of the hole portion to be inserted into the heating furnace from the hole portion. However, the present invention is not limited to two divisions.
Furthermore, by forming the tapered portion, the center of gravity moves to the upper side (inner side of the heating furnace) of the seal member, and when the seal member is pushed upward from below, the difference between the outer diameter of the body portion and the diameter of the hole portion The presence of the (gap) allows the seal member to spread outward (left and right in the case of two divisions), and helps the left and right weight balance to easily spread laterally.

In the first aspect, the large diameter side of the tapered portion may be equal to or less than or equal to the diameter of the hole in the hole. The large diameter side of the tapered portion preferably has a diameter substantially equal to the diameter of the hole, but the category including the diameter equal to or less than the diameter of the hole includes the diameter of the trunk as the minimum diameter. That is, when the large diameter side of the tapered portion has the same diameter as the diameter of the body portion, the tapered portion substantially does not exist, but the present invention also includes this.

In the second aspect of the present invention, the combustion tube is a reaction unit that burns, oxidizes and decomposes the carbon component in the sample to convert it to carbon dioxide, and light is transmitted to the cell and the cell that circulates the gas from the reaction unit. It is a total organic carbon measuring apparatus provided with the measurement part which has a light source which irradiates, and a detector which detects the light which permeate | transmitted the cell.

According to the analyzer according to the first aspect of the present invention, the lower portion of the casing of the heating furnace is a seal member made of a heat insulating material having a hole at its central portion for inserting and holding a thin tube portion at the outlet of the combustion tube main body. The heat exchanger can be effectively thermally insulated simply by installing the combustion pipe in the heating furnace, since it is mounted in the hole of the housing to seal the heat outflow. Further, since the thin tube portion at the outlet of the combustion tube main body is held by the lower housing of the heating furnace via the seal member, it can be stably attached in the heating furnace.
Furthermore, in the embodiment in which the seal member is divided, even if the seal member is provided with the flange portion, the seal member can be easily attached from the hole bored in the lower portion of the casing of the heating furnace. It can be easily performed only by pushing up the seal member upward (inside the heating furnace) in inserting the hole into the hole in the center part.
Therefore, the variation at the time of attachment of the combustion pipe in a heating furnace by a worker can be eliminated, and stable measurement of total organic carbon etc. becomes possible.

It is a flow-path block diagram which shows one Example of a total organic carbon measuring apparatus. It is sectional drawing which shows the seal member with which the housing | casing lower part of a heating furnace is mounted | worn, and shows the shape of a seal member. It is sectional drawing which shows the seal member with which the housing | casing lower part of a heating furnace is mounted | worn, and shows the state before attaching a combustion pipe to a seal member. It is sectional drawing which shows the sealing member with which the housing | casing lower part of a heating furnace is mounted | worn, and shows the state after attaching a combustion pipe to a sealing member, respectively.

Hereinafter, the analyzer of the present invention will be described using the drawings. First, an all-organic carbon measuring apparatus will be described as an example of an embodiment of an analyzing apparatus with reference to FIG.

In FIG. 1, the all-organic carbon measuring apparatus 11 supplies a carrier gas to send a carrier gas to the all-organic carbon measuring unit 12 and the combustion tube 14 of the oxidation reaction unit 13 provided in the all-organic carbon measuring unit 12. And a multiport valve 16 for switching them.
A sampling syringe 17 for measuring and collecting sample water is connected to a common port of the multiport valve 16. Although not shown, other ports include 1) a sample introduction unit, 2) hydrochloric acid used when removing inorganic carbon components from sample water, 3) dilution water, and 4) inorganic carbon reaction unit 18 5) The combustion pipes 14 and 6) The drain drain ports are connected to one another. As described above, the total organic carbon measurement apparatus 11 is configured to be able to inject the sample collected from the autosampler 19 into the combustion pipe 14 of the total organic carbon measurement unit 12.

An exemplary volume of the sampling syringe 17 is around 5 mL. At the lower part of the barrel of the sampling syringe 17, a vent gas inlet (not shown) for introducing a carrier gas is provided. The vent gas inlet is connected to the carrier gas supply unit 15 via the solenoid valve 20. In this embodiment, the gas venting mechanism is realized by the sampling syringe 17.

The carrier gas supply unit 15 is configured to supply high purity air as a carrier gas. Although not shown, the carrier gas supply unit 15 includes, in order from the upstream side, a carrier gas inlet, a solenoid valve, a pressure regulating valve that regulates pressure, a pressure gauge that measures pressure, a mass flow controller that regulates flow, a flow meter, And the humidifier is connected.
The carrier gas whose flow rate is measured and humidified is sent to the combustion tube 14. Further, the carrier gas whose flow rate is adjusted for humidification is also supplied to the sampling syringe 17 as a ventilation gas through the solenoid valve 20.

The combustion tube 14 of the oxidation reaction unit 13 includes a sample injection unit 21 at the top. A thin tube portion 14 a is provided at the outlet of the combustion tube 14 main body. An oxidation catalyst for converting all of the carbon components in the sample into carbon dioxide is held at the inlet of the thin tube portion 14a. The oxidation catalyst may contain a metal oxide or a noble metal. The combustion tube 14 is inserted into the heating furnace 22 and heated to 680 ° C., for example.
The carrier gas supply unit 15 is connected to the sample injection unit 21 via a check valve (not shown) that prevents backflow of the carrier gas. The narrow tube portion 14 a of the combustion tube 14 main body is connected to the carrier gas inlet of the inorganic carbon reaction unit 18 via the cooling unit 23 and the backflow prevention trap 24.

Although the inorganic carbon reaction unit 18 is not illustrated, when measuring inorganic carbon, phosphoric acid is supplied as an inorganic carbon reaction liquid by an optional means such as a pump, and the sample water is supplied to the inorganic carbon reaction unit 18 as a multiport valve. Direct injection is performed by the switching of 16 and the operation of the sampling syringe 17. In the injected sample water, inorganic carbon is generated as carbon dioxide, and the carbon dioxide is led to the dehumidifying electron cooler 25.
The inorganic carbon reaction liquid of the inorganic carbon reaction unit 18 is discharged from a drain solenoid valve (not shown).

Although not shown, the gas passed through the dehumidifying electron cooler 25 is not shown as a non-dispersive infrared analysis method (NDIR) via a dehumidifier for removing water or a membrane filter (for removing a halogen scrubber and foreign matter). ) To the measurement unit 26). Although not illustrated, the measurement unit 26 includes a cell in which a light source and a detector are disposed opposite to each other. The intensity of the detector output signal corresponds to the amount of total carbon or inorganic carbon.
The amount of inorganic carbon can be determined by subtracting the amount of inorganic carbon from the amount of total carbon measured in this manner.
The discharged carbon dioxide is adsorbed by a CO 2 absorber (not shown). Further, a drain pot (not shown) for removing water is connected to the dehumidifying electronic cooler 25.

Next, the oxidation reaction unit 13 will be described with reference to FIG. The oxidation reaction unit 13 includes a heating furnace 22 and a combustion tube 14 (see FIG. 2C) attached to the inside of the heating furnace 22.
In FIG. 2A, the lower casing 22a of the heating furnace 22 penetrates the casing 22a in the thickness direction (the thickness of the casing 22a is indicated by t in FIG. 2) and the outer diameter of the main body of the combustion tube 14 A hole 7 having a hole diameter d2 larger than d1 (see FIG. 2C) is provided. The reason for this configuration is to allow removal when the combustion tube 14 is broken inside the heating furnace 22 and is a structure that can not be avoided for maintenance.

The seal member 1 is mounted in a hole 7 provided in the lower housing 22 a of the heating furnace 22. The seal member 1 is divided into two. The seal member 1 has rod-shaped body portions 4a and 4b. The body portions 4 a and 4 b have a diameter smaller than the diameter d 2 of the hole 7. The length of the body portions 4 a and 4 b (the dimension in the thickness direction of the lower housing 22 a) is larger than the thickness of the lower housing 22 a of the heating furnace 22. The flanges 2a, 2b, 3a, 3b are connected to both ends of the body 4a, 4b (in the thickness direction of the lower housing 22a). The flanges 2a, 2b, 3a, 3b have a diameter d3 larger than the diameter d2 of the hole 7. . Further, a hole 6 is provided at the center of the seal member 1. The hole 6 may be provided at a position deviated from the central portion of the seal member 1. The narrow tube portion 14 a of the main body of the combustion tube 14 is inserted into the hole 6.
Among the flanges 2a, 2b, 3a, 3b, the upper flanges 2a, 2b are not disk-like, as shown in the top view of FIG. Thereby, the seal member 1 (upper flanges 2a and 2b) can be mounted in the heating furnace 22 from the hole 7 while maintaining the function as the flanges 2a and 2b.

The seal member 1 is formed with tapered portions 5a, 5b that taper from the upper flange portions 2a, 2b toward the body portions 4a, 4b. In this embodiment, as shown in FIG. 2A, the maximum diameter of the tapered portions 5a and 5b is set to the same diameter as the inner diameter d2 of the hole portion 7.
The minimum diameter of the tapered portions 5a, 5b is the same as the diameter of the body portions 4a, 4b. The position of the smallest diameter portion in the body portions 4a and 4b is desirably equal to or less than the upper one-third of the length (axial direction) of the body portions 4a and 4b. Thus, the tapered portions 5 a and 5 b can position the center of gravity of the seal member 1 upward (inside the heating furnace 22).

Hereinafter, an operation of attaching the combustion pipe 14 (thin tube portion 14a) to the seal member 1 will be described with reference to FIGS. 2A to 2C.
When attaching the thin tube portion 14a at the outlet of the combustion tube 14 to the hole 6 bored in the center of the seal member 1 in FIG. 2B, the lower flange portions 3a and 3b are heating furnaces from the state of FIG. 2A. The seal member 1 is pushed upward into the heating furnace 22 by hand until it abuts on the lower housing 22a of 22.

Since the seal member 1 is divided into two parts, as shown in FIG. 2B, the seal member 1 spreads to the left and right due to the difference (gap) between the outer diameter of the body 4a, 4b and the hole diameter d2 of the hole 7. Here, the center of gravity is located at the upper part by forming the tapered portions 5a and 5b. This helps the seal member 1 to spread to the left and right easily with the upper and lower weight balance.
A chamfered portion 8 is formed on the lower flange 3a, 3b side of the hole 6 provided in the sealing member 1. As a result, the collision of the lower flanges 3a and 3b of the seal member 1 can be alleviated, and the left and right spread can be further permitted.

As shown in FIG. 2C, the hand pushing up the seal member 1 while inserting the thin tube portion 14a of the combustion tube 14 from the inside of the heating furnace 22 into the hole 6 of the seal member 1 When released, the seal member 1 is fixed around the narrow tube portion 14 a and can be held by the seal member 1. The seal member 1 is pushed down until the upper flanges 2a and 2b abut against the hole 7, and the taper is set such that the upper flanges 2a and 2b and the maximum diameter are the same as the inner diameter d2 of the hole 7 The holes 7 are sealed and thermally insulated by 5a and 5b.
In the illustrated embodiment, the maximum diameters of the tapered portions 5 a and 5 b are set to the same diameter as the inner diameter d 2 of the hole 7. As a result, even if the flanges 2a and 2b above the seal member 1 are not disk-like but partially cut away, heat does not escape from the cutouts of the upper flanges 2a and 2b.

While exemplary embodiments of the present invention have been described above, the scope of the present invention should not be limited to the described embodiments, but should be understood to encompass various embodiments. Hereinafter, aspects of the present invention will be described.

The first aspect of the present invention is
An analyzer comprising a heating furnace for heating a combustion tube into which a sample is introduced, thereby burning the sample for oxidative decomposition.
A thin tube portion is provided at the outlet of the combustion tube,
The heating furnace has a housing,
The lower part of the casing of the heating furnace is provided with a hole penetrating the casing,
The diameter of the hole is larger than the outer diameter of the combustion tube,
The hole is provided with a sealing member for sealing the hole,
The sealing member is made of a heat insulating material,
The sealing member is provided with a hole for inserting a thin tube portion of the combustion tube,
It is an analyzer.

In the first aspect of the present invention,
The seal member may have a body and a brim.
The body may have a diameter smaller than the diameter of the hole and may have a length larger than the thickness of the lower casing of the heating furnace.
The flanges may be provided at both ends of the body,
The flange may have a diameter larger than the diameter of the hole,
The seal member may have a tapered portion formed from the flange portion toward the body portion.
The seal member may be divided into at least two in the axial direction. .

In the first aspect of the present invention,
The tapered portion may have a diameter equal to or less than the diameter of the hole on the large diameter side.

The second aspect of the present invention is
An all-organic carbon measuring apparatus comprising a measuring unit,
The combustion tube is a reaction unit which is disposed in the heating furnace and burns, oxidizes and decomposes a carbon component in a sample, and converts it into carbon dioxide.
The measuring unit is an all-organic carbon measuring apparatus having a cell for circulating the gas from the reaction unit, a light source for irradiating the cell with light, and a detector for detecting the light transmitted through the cell.

1 · · · Seal member 2a, 2b · · · upper flange portion 3a, 3b · · · lower flange portion 4a, 4b · · · body portion 5a, 5b · · · taper portion 6 · · · hole 7 · · · · Holes 8 · · · Chamfered portion 11 · · · Total organic carbon measurement device 12 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · oxidation tube 14 · · · · · · · · · narrow tube Carrier gas supply unit 16 Multiport valve 17 Sampling syringe 18 Inorganic carbon reaction unit 19 Autosampler 20 Solenoid valve 21 Sample injection unit 22 · Heating furnace 22a · · · Lower housing 23 of heating furnace · · · Cooling unit 24 · · · · reverse flow prevention trap 25 · · · electronic cooler for dehumidification · · · · · measurement unit d1 · · · · · · diameter of the main body of the combustion tube d2 ··· Hole diameter of hole d 3 ··· Diameter of flange portion t ··· Case Body thickness

Claims

An analyzer comprising a heating furnace for heating a combustion tube into which a sample is introduced, thereby burning the sample for oxidative decomposition.
A thin tube portion is provided at the outlet of the combustion tube,
The heating furnace has a housing,
The lower part of the casing of the heating furnace is provided with a hole penetrating the casing,
The diameter of the hole is larger than the outer diameter of the combustion tube,
The hole is provided with a sealing member for sealing the hole,
The sealing member is made of a heat insulating material,
The sealing member is provided with a hole for inserting a thin tube portion of the combustion tube,
Analysis equipment.
The analyzer according to claim 1, wherein
The seal member has a body and a brim.
The body has a diameter smaller than the diameter of the hole and has a length larger than the thickness of the lower case of the heating furnace.
The flanges are provided at both ends of the body,
The flange portion has a diameter larger than the diameter of the hole, and the seal member is formed with a tapered portion from the flange portion toward the body portion.
The analyzer is characterized in that the seal member is divided into at least two in the axial direction.
The analyzer according to claim 2, wherein
The analyzer according to claim 1, wherein the tapered portion has a diameter equal to or less than the diameter of the hole on the large diameter side.
An analyzer according to claim 1;
An all-organic carbon measuring apparatus comprising a measuring unit,
The combustion tube is a reaction unit which is disposed in the heating furnace and burns, oxidizes and decomposes a carbon component in a sample, and converts it into carbon dioxide.
The measurement unit includes a cell for circulating the gas from the reaction unit, a light source for irradiating the cell with light, and a detector for detecting the light transmitted through the cell.