JP2998601B2 - Sample injection method for total organic carbon meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Total organic carbon meter (TOC meter) for measuring C (total organic carbon)
About.

[0002]

2. Description of the Related Art In recent years, measurement of organic carbon contained in water such as water supply and sewage water, water for various plants, rivers, and the like has become one of the important items for pollution investigations and the like. An organic carbon meter (TOC meter) is used.

The total organic carbon meter mainly measures the total organic carbon concentration directly by burning an aqueous solution sample from which inorganic carbon (IC) has been removed by bubbling or the like in advance in a combustion tube and measuring the carbon dioxide generated. There are known those that measure, and those that directly burn a solution sample and measure the organic carbon concentration by subtracting the separately measured inorganic carbon measurement value from the measured total carbon (TC) measurement value. . In such a total organic carbon meter, in order to accurately measure the total organic carbon concentration, it is necessary to pour a desired amount of the aqueous solution sample into the combustion tube with extremely high accuracy.

FIG. 3 shows a combustion section 14 in the total organic carbon meter.
In the figure, the vicinity of an aqueous solution sample is conventionally used for a combustion tube 1
4e, first, the sample injection section 14a is slid as shown in the figure, a syringe pump (not shown) is driven, and the sample to be measured is stored in the drain tube 14c until the sample injection tube 13b is sufficiently washed. Then, the sample injection part 14a is slid in the opposite direction, and the sample injection tube 13b and the injection port 1 into the combustion tube 14e are discharged.
4d, the desired amount of the aqueous solution sample was injected into the combustion tube 14e by driving a syringe pump (not shown).

[0005]

However, as shown in FIG. 3, the aqueous solution sample is discharged into the drain tube 14c for washing, and the aqueous solution sample in the sample injection tube 13b immediately after the draining is completed. Due to the surface tension of the sample itself and the contamination of the tube tip, the tube 13b
In many cases, the volume of the aqueous solution sample remaining in the tube 13b is different at every washing.

In such a case, the amount of the aqueous solution sample injected into the combustion tube 14 differs by the amount of the aqueous solution sample just before the tip of the sample injection tube 13b, causing a measurement error of the total organic carbon concentration.

Accordingly, an object of the present invention is to provide a method for injecting a desired aqueous solution sample into a combustion tube more accurately in a total organic carbon meter in order to solve such a problem.

[0008]

According to the present invention, a syringe pump is connected to a common port of a multi-port valve, and at least a reaction section of a reaction section is connected to each of a plurality of distribution ports. All organic carbon connected with a sample injection tube connected to a sample injection section that can be switched to a tube and drain, a drain tube connected to the drain, a sample suction tube for sucking an aqueous solution sample, and a washing solution suction tube for sucking a washing solution A method for injecting a sample into the sample, wherein the sample injecting section in the reaction section is switched to a drain side, and the washing liquid is discharged to the drain through the sample injecting tube and the sample injecting section by the syringe pump. After washing the tube, the washing solution in the sample injection tube is washed with the syringe pump. After completely sucking, the solution is completely discharged through the drain tube or the washing solution suction tube. After the discharge, the aqueous sample is sucked from the sample suction tube by the syringe pump. Is switched to the connected distribution port, and the aqueous solution sample obtained by adding the previously determined internal volume of the sample injection tube and the desired amount to be injected into the reaction section is transferred from the syringe pump to the sample injection tube and the reaction tube side of the reaction section. It is characterized in that a desired amount of the aqueous solution sample is injected into the reaction section by pouring out through the switched sample injection section.

In addition, a syringe pump is connected to a common port of the multi-port valve, and a sample injection tube connected to at least a reaction tube of the reaction unit and a sample injection unit switchable to a drain at each of the plurality of distribution ports.
A sample injection method in a total organic carbon meter to which a drain tube connected to a drain and a sample suction tube for sucking an aqueous solution sample are connected, wherein a sample injection portion of a reaction section is switched to a drain side, and the aqueous sample is transferred to the syringe. By discharging the sample injection tube to the drain through the sample injection tube and the sample injection unit by a pump, the sample injection tube is washed, and after washing, the aqueous solution sample in the sample injection tube is completely aspirated by the syringe pump. After discharging through the drain tube or the sample suction tube and sucking the aqueous sample again from the sample suction tube, the multi-port valve is switched to a distribution port to which a sample injection tube is connected, and the sample obtained in advance is determined. An aqueous solution sample containing the internal volume of the injection tube and the desired amount to be injected into the reaction section was added. Serial from a syringe pump to dispense through the sample injection unit switched into the reaction tube side of the sample injection tube and the reaction section, characterized by injecting the desired amount of the aqueous solution sample into the reaction unit.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is an overall schematic view of a total organic carbon meter for carrying out the present invention. A multi-port valve 1 includes a common port 1z and four distribution ports 1a to 1d.
Driven by the motor M, the common port 1z and each of the distribution ports 1a to 1d are selectively connected.

The syringe pump 2 is driven by a motor M2, and aspirates an aqueous sample or washing solution from a sample suction tube 3a and a washing solution suction tube 3c connected to the distribution ports 1a and 1c, respectively.
The sucked aqueous sample or the like is discharged to the combustion section 4 or the drain via the sample discharge tube 3b and the drain tube 3d connected to 1d.

The combustion section 4 burns an aqueous solution sample supplied from the syringe pump 2 via the sample discharging tube 3b, converts carbon components in the aqueous solution sample into carbon dioxide, and as a combustion gas together with a carrier gas (not shown). To the carbon dioxide detector. The sample injection section 4a is provided with a sample injection tube 4b connected to the sample injection tube 3b, and has a motor M3.
The aqueous solution sample or the cleaning liquid discharged from the sample discharge pipe 4b is selectively discharged to the drain pipe 4c or the combustion pipe 4e connected to the drain.

FIG. 2 shows a sample discharging tube 4b of the combustion section 4 via a sample discharging tube 3b in the total organic carbon meter.
FIG. 3 is a detailed cross-sectional view of the multi-port valve 1 connected to the sample ports, showing connection portions between the sample suction tube 3a and the sample discharge tube 3b and the distribution ports 1a and 1b.

As shown in FIG. 1, the multi-port valve 1 includes a fixed block 1g having a common port 1z and distribution ports 1a to 1d (not shown for the distribution ports 1c and 1d), and a fixed block 1g. And has a pivot block 1e formed in such a manner as to be in close contact engagement with the pivot block and rotatably formed therein. The pivot block 1e has a common port 1z and a distribution port 1a.
1d is formed to selectively connect .about.1d.

With this configuration, the common port 1
z denotes distribution ports 1a to 1d connected via a line 1f.
The other distribution ports that are not connected to the common port 1z are completely disconnected from the common port 1z by the close contact engagement between the rotating block 1e and the fixed block 1g. Note that the combustion unit 4 has the same configuration as that of FIG. 1, and a description thereof will be omitted.

Next, a method for pouring a predetermined amount of the aqueous solution sample according to the present invention into the combustion section 4 will be described. First, while connecting the multi-port valve 1 to the distribution port 1c,
The sample injection part 4a of the combustion part 4 is switched to the drain pipe 4c.

Then, the cleaning liquid is supplied to the cleaning liquid suction tube 3c.
, The multi-port valve 1 is switched to the distribution port 1b, and the syringe pump 2 is pushed up to discharge the washing liquid to the drain pipe 4c through the sample discharging tube 3b, thereby discharging the sample. Tube 3
b.

After the washing, the syringe pump 2 is pulled down to completely aspirate the washing solution in the sample injection tube 3b,
The multi-port valve 1 is switched to the distribution port 1d or the distribution port 1c, and the syringe pump 2 is pushed up to completely discharge the liquid through the drain tube 3d or the washing liquid suction tube 3c.

After discharging, the multi-port valve 1 is switched to the distribution port 1a, the syringe pump 2 is lowered, and the aqueous solution sample is sucked from the sample suction tube 3a.
The multi-port valve 1 is switched to the distribution port 1b, and the sample injection block 4a is slid so that the sample discharge tube 3b and the combustion tube 4e communicate. FIG. 2 shows the state of the aqueous solution sample in the syringe pump 1 immediately after switching the multiport valve 1 to the distribution port 1b after sucking the aqueous solution sample from the sample suction tube 3a.
Since the fixed block 1g and the rotating block 1e are in close contact with each other, the aqueous solution sample in the pipeline 1f after the switching is always in a solid state of FIG. 2 cut off by the fixed block 1g.

Then, the previously determined sample injection tube 3b
By pushing up the syringe pump 2 and injecting the aqueous solution into which the desired volume to be injected into the combustion tube 4e into the combustion tube 4e via the sample injection tube 3b, the solution shown in FIG.
A predetermined amount of the aqueous solution sample is discharged from the streak-cut state, so that a desired amount of the aqueous solution sample is accurately injected into the combustion tube 4e.

Next, a method of washing the sample injection tube 3b with the aqueous solution sample itself to be measured when the aqueous solution sample is injected into the combustion tube 4 will be described. First, prior to the measurement, the multi-port valve 1 is connected to the distribution port 1a, and the sample injection section 4a of the combustion section 4 is switched to the drain pipe 4c.

Then, the aqueous solution sample is transferred to the sample suction tube 3.
a, the multiport valve 1 is switched to the distribution port 1b, and the syringe pump 2 is pushed up to discharge the aqueous solution sample to the drain tube 4c through the sample discharging tube 3b. The pouring tube 3b is washed with the aqueous solution sample to be measured.

After washing, the aqueous solution sample in the sample injection tube 3b is completely sucked by pulling down the syringe pump 2, and the multiport valve 1 is switched to the distribution port 1d or the distribution port 1a, and the syringe pump 2 is pushed up. The aqueous solution sample in the pump 2 is
d or discharged through the sample suction tube 3a.

After the discharge, the multiport valve 1 is switched to the distribution port 1a, the syringe pump 2 is lowered, and the aqueous sample is again sucked from the sample suction tube 3a. After the suction, the multiport valve 1 is switched to the distribution port 1b. The sample injection part 4a is slid, and the sample discharge tube 3b and the combustion tube 4e are connected. Even in such a case, as described above, since the fixed block 1g and the rotating block 1e are in close contact with each other, the aqueous solution sample in the pipeline 1f after switching is always shown in a solid state in FIG. Then, the aqueous solution sample is in a state of being streaked by the fixed block 1g.

Then, the previously determined sample injection tube 3b
By pushing up the syringe pump 2 and injecting the aqueous solution into which the desired volume to be injected into the combustion tube 4e into the combustion tube 4e via the sample injection tube 3b, the solution shown in FIG.
Since a predetermined amount of the aqueous solution sample is injected from the striped state, a desired amount of the aqueous solution sample is injected into the combustion tube 4e with high accuracy.

[0027]

According to the present invention, after the sample injection tube is washed with the washing liquid or the aqueous solution sample itself to be measured, the cleaning liquid or the aqueous solution sample in the sample injection tube is once completely discharged, and the sample is again measured. Since it is desired to suction the aqueous solution sample and discharge it to the combustion pipe by a predetermined amount from the streak cut state of the distribution port of the multi-port valve, it is possible to always accurately discharge the desired amount of the aqueous solution sample.

[Brief description of the drawings]

FIG. 1 is an overall schematic diagram of a total organic carbon meter used in the present invention.

FIG. 2 is a detailed view of a multi-port valve of the total organic carbon meter used in the present invention.

FIG. 3 is a diagram showing the vicinity of a combustion section of a conventional total organic carbon meter.

[Explanation of symbols]

 1 Multi-port valve 1z Common port 1a to 1d Distribution port 1e Rotating block 1f Pipe 1g ... Fixed block 2... Syringe pump 3a... ····· Drain tube 3d 4 ···· Combustion unit 4a ··· Sample injection unit 4e ···· Combustion tube

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Kitamura 1 Shiwazu Nishinokyo Kuwaharacho, Nakagyo-ku, Kyoto Co., Ltd. Sanjo Plant (72) Inventor Hideto Nakagami 1 Shizuzu Kuwaharacho, Nishinokyo, Nakagyo-ku, Kyoto Co., Ltd. Inside the Sanjo Plant (72) Inventor Yuko Yamachi 1 Nishinokyo Kuwabaracho, Nakagyo-ku, Kyoto Shimazu Works Sanjo Plant (56) References JP-A-8-297041 (JP, A) JP-A-1-68658 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01N 31/00 G01N 1/00 101

Claims (2)

(57) [Claims] A syringe pump connected to a common port of the multi-port valve, and a sample injection tube connected to each of the plurality of distribution ports at least to a sample injection unit switchable to a reaction tube and a drain of a reaction unit; A sample injection method in a total organic carbon meter to which a drain tube connected to a drain, a sample suction tube for sucking an aqueous solution sample, and a washing solution suction tube for sucking a washing solution, wherein the sample injection unit in the reaction unit is provided. Is switched to the drain side, and the washing liquid is discharged to the drain through the sample injection tube and the sample injection unit by the syringe pump, thereby washing the sample injection tube. After the washing, the sample injection tube is washed by the syringe pump. After completely aspirating the washing solution inside, the drain tube or the washing solution The solution was completely discharged through a suction tube. After the discharge, the aqueous solution sample was suctioned from the sample suction tube by the syringe pump, and the multiport valve was switched to a distribution port to which a sample injection tube was connected. An aqueous solution, to which the internal volume of the sample injection tube and the desired amount to be injected into the reaction section are added, is discharged from the syringe pump through the sample injection tube and the sample injection section switched to the reaction tube side of the reaction section. Thereby injecting a desired amount of the aqueous solution sample into the reaction section. 2. A sample injection tube connected to a common port of the multi-port valve and connected to at least one of a plurality of distribution ports at least to a reaction tube of the reaction unit and a sample injection unit switchable to a drain, What is claimed is: 1. A method for injecting a sample in a total organic carbon meter to which a drain tube connected to a drain and a sample suction tube for sucking an aqueous solution sample are connected. The sample injection tube is washed by discharging the sample injection tube to the drain through the sample injection tube and the sample injection unit by a pump, and after washing, the aqueous solution sample in the sample injection tube is completely aspirated by the syringe pump. , The sample is discharged through the drain tube or the sample suction tube, and the sample is sucked again. After aspirating the aqueous solution sample from the tube, the multiport valve is switched to a distribution port to which a sample injection tube is connected, and an aqueous solution containing the previously determined internal volume of the sample injection tube and a desired amount to be injected into the reaction section is added. A desired amount of an aqueous sample is injected into the reaction section by pouring a sample from the syringe pump through the sample injection tube and the sample injection section switched to the reaction tube side of the reaction section. Sample injection method for total organic carbon meter.