JPH0718859B2 - Carbon content measuring device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a carbon content measuring device, and particularly to a carbon content measurement suitable for measuring the content of organic carbon in river water quality inspection and the like. It relates to the device.

[Prior Art] Conventionally, when conducting a water quality test, it has been mentioned that one of the test items is to measure the content of organic carbon. No.
63-135858) has already proposed a "carbon content measuring device".

This carbon content measuring device comprises a sample supply means for supplying a sample containing organic carbon, a reaction solution supply means for supplying a reaction solution to the sample, an organic carbon in the sample and a reaction solution at a predetermined pressure. A reactor for producing carbon dioxide by reacting at a predetermined temperature, an extraction means for extracting carbon dioxide from a reaction completion liquid passing through this reactor, and a measurement for detecting the amount of carbon dioxide extracted by this extraction means And means.

Then, in order to reliably carry out the reaction between the sample and the reaction solution in the reactor (oxidative decomposition action of organic carbon contained in the sample), it is necessary to place the sample and the reaction solution under high pressure and high temperature. Therefore, in the above-mentioned conventional carbon content measuring device, a throttle is provided in the middle of the transportation pipeline for transporting the sample from the reactor to the extractor, and the flow rate of the sample on the downstream side of the reactor is reduced by this throttle. By limiting
Attempts have been made to increase the pressure of the sample upstream of the restriction, ie in the reactor.

[Problems to be Solved by the Invention] The present invention is intended to solve the following problems in the above-described conventional techniques.

That is, as described above, when an attempt is made to increase the pressure of the sample in the reactor by providing a throttle in the middle of the transportation pipeline located on the downstream side of the reactor, the pressure between the reactor and the extractor is increased. , A throttle and its fixing device must be interposed, which lengthens the transport line formed between the reactor and the extractor, before the sample exiting the reactor reaches the extractor. The problem is that the temperature drops.

Since such a problem causes a decrease in the extraction efficiency of carbon dioxide in the extractor, there is a demand for countermeasures against it.

Then, as one means for solving the above-mentioned problems, it is conceivable to provide a heat retaining device or a heating device in the transportation pipeline formed between the reactor and the extractor. However, it is not an effective means because it complicates the device and increases the operating cost.

[Means for Solving Problems] An object of the present invention is to provide a carbon content measuring apparatus capable of effectively solving the above-mentioned conventional problems, and in order to achieve this object, the present invention is concerned. The carbon content measuring device is supplied with a sample containing organic carbon and a reaction solution mixed in the sample, and heats the sample and the reaction solution at a high temperature.
By reacting under high pressure, a reactor that oxidatively decomposes the organic carbon to produce carbon dioxide, a measuring unit that detects the amount of carbon dioxide produced in this reactor, and a reactor that is routed into the reactor. A pipe for forming a reaction pipeline between the sample and the reaction solution, and for forming a transport pipeline for feeding the sample after the reaction from the reactor to the measuring means, and the reaction pipeline of the pipeline is provided. In the portion to be formed, a narrowed portion is formed near the side connected to the transportation pipeline.

[Operation] The carbon content measuring apparatus according to the present invention limits the flow rate of the sample or the reaction solution by the narrowed portion formed on the downstream side of the reaction tube, so that the sample or the reaction solution on the upstream side of the reaction tube is While increasing the pressure, the throttling portion is positioned in the reactor, and inclusions are removed from between the reactor and various devices in the subsequent stage to narrow the gap between them as much as possible.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

In the figure, reference numeral 1 indicates a carbon content measuring apparatus of this embodiment, a sample supply pump (sample supply means) 2 and a sample supply line 3 connected to the suction side of the sample supply pump 2.
Sample supply pipe 4 connected to the discharge side of the sample supply pump 2
And a reaction liquid which is connected in the middle of the sample supply pipe 4 and reacts with the carbon compound in the sample sent from the sample supply pump 2 (in this embodiment, it is composed of an aqueous solution of sulfuric acid and potassium persulfate). A reaction liquid supply pump (reaction liquid supply means) 5 for supplying the degasser, a deaerator 6 connected to the downstream end of the sample supply pipe 4, and a degasser 6 connected via a pipe 7. And a pressurizing pump 8 for pumping the sample and the reaction solution sent out from the deaerator 6 to the subsequent stage, and the pressurizing pump 8
By heating and reacting the sample and the reaction solution that have been pressure-fed by, the reactor 9 that oxidatively decomposes the organic carbon contained in the sample to generate carbon dioxide, and the sample after the completion of the reaction are sent, An extractor 10 for extracting the carbon dioxide produced in the reactor 9 from the sample, a measuring means 11 for detecting the amount of the extracted carbon dioxide, the pressurizing pump 8 through the reactor 9 and the extractor 10 A pipe 12 that forms a pipe line for transporting a sample to and a pipe 13 that connects the extractor 10 and the measuring means 11 are provided.

The reactor 9 is composed of a drum heater 14 and a reaction pipe 15 wound around the drum heater 14, and the sample transport pipe 12 has the reaction pipe 15 at an intermediate portion thereof. And connecting to both ends of the reaction pipeline 15 are transport pipelines 16 and 17.

Further, in the present embodiment, a fixed throttle 18 is provided in the vicinity of the connecting portion with the transport pipeline 17 on the downstream side of the reaction pipeline 15 to form a throttle portion.

Further, an air supply pipe 6a for feeding an inert gas such as helium or high-purity nitrogen is connected to a lower portion of the deaerator 6, and the inert gas supplied from the air supply pipe 6a is a deaerator. The reaction liquid (sulfuric acid aqueous solution) and the sample are agitated and mixed with each other in the interior of 6 to degas the carbon dioxide (inorganic carbon) in the sample. Is the carbon dioxide separated inside and the air supply pipe
An exhaust pipe 6b for discharging the inert gas supplied from 6a to the outside is provided.

On the other hand, the lower part of the extractor 10 has helium inside,
A supply pipe 10a for feeding an inert gas such as high-purity nitrogen is connected, and the inert gas supplied from the supply pipe 10a is bubbled inside the extractor 10 and is generated in the reactor 9. Carbon dioxide is separated from the sample.

The measuring means 11 is composed of an infrared analyzer and is adapted to quantify the carbon dioxide contained in the gas sent through the pipe 13.

Further, the drain after the carbon dioxide is extracted in the extractor 10 (the liquid after removing impurities) is sent to the drain tank 20 through the pipe 19 provided in the lower part of the extractor 10. There is.

Next, the operation of the device will be described.

At the start of the measurement, the sample supply pump 2, the reaction solution supply pump 5, and the pressurizing pump 8 are driven, and the drum heater 14 of the reactor 9 is supplied with electric power, whereby the organic carbon contained in the sample is removed. The quantity becomes measurable.

Under this condition, when the sample is supplied from the sample supply line 3 through the sample supply pump 2 and the reaction liquid composed of sulfuric acid and potassium persulfate is supplied from the reaction supply pump 5, the deaerator 6 is operated. Carbon dioxide (inorganic carbon) in the sample is removed by sulfuric acid in the reaction solution and is discharged to the outside by an inert gas supplied into the deaerator 6, and further contained in this sample in the reactor 9. Carbon dioxide is produced by the reaction of the organic carbon with the potassium persulfate.

The carbon dioxide produced in the reactor 9 is transported to the extractor 10 and separated from the sample by the inert gas supplied into the extractor 10 and then sent to the measuring means 11 quantitatively. It is analyzed, and the amount of organic carbon contained in the sample is calculated based on the analysis result.

In the course of such a measurement operation, of the reaction pressure and temperature that greatly affect the reaction between organic carbon in the sample and potassium persulfate, the temperature is controlled by controlling the energization of the drum heater 14, and the other reaction is performed. For pressure, the reaction line
The set value is held by the action of the fixed throttle 18 provided at the downstream end of 15.

Since the fixed throttle 18 is provided in the reaction pipe line 15 which constitutes the reactor 9, the reactor 9 and the extractor
Direct contact with 10 is possible and the distance between the two is greatly reduced.

As a result, the cooling of the sample during the transportation from the reactor 9 to the extractor 10 is suppressed, the extraction efficiency of carbon dioxide in the extractor 10 is improved, and thus the measurement accuracy of carbon dioxide is improved, and A device for heating and keeping heat during transportation is not required, which simplifies the configuration and suppresses cost.

It should be noted that the constituent members and the like shown in the above-described embodiment are merely examples, and can be variously changed based on design requirements and the like.

For example, an example in which the throttle portion is formed by providing a fixed throttle at the end portion on the downstream side of the reaction pipe has been shown, but about half the pipe diameter on the downstream side can be uniformly reduced. Good.

Further, although potassium persulfate was used as a reagent for oxidizing organic carbon, it is not necessarily limited to this, and permanganate such as potassium permanganate or chromate such as potassium chromate may be used. .

Further, the reaction liquid supplied from the reaction liquid supply pump 7 is only the potassium persulfate aqueous solution, and the reaction liquid supply pump 7
Separately from the above, a supply means for exclusively supplying the aqueous solution of sulfuric acid may be provided.

[Effects of the Invention] As described above, the carbon content measuring apparatus according to the present invention is supplied with a sample containing organic carbon and a reaction solution mixed in the sample, and supplies these samples and the reaction solution. A reactor that oxidatively decomposes the organic carbon to produce carbon dioxide by reacting at a high temperature and a high pressure, a measuring unit that detects the amount of carbon dioxide produced in the reactor, and a reactor inside the reactor. A pipe for forming a reaction pipe line between the sample and the reaction solution which is rotated, and for forming a transport pipe line for sending the sample after the reaction from the reactor to the measuring means, and the reaction pipe of the pipe. In the portion forming the passage, a narrowed portion is formed in the vicinity of the side connected to the transport pipeline, and the reaction pressure of the sample in the reactor is set in the reactor. Depending on the reactor and the subsequent machines Remove the inclusions between the reactor and the space between them as much as possible, thus suppressing the cooling of the sample discharged from the reactor while it is being transported to the various equipment in the subsequent stage. It is possible to improve the measurement accuracy, and it is possible to simplify the configuration and reduce the cost by eliminating the device for keeping heat and heating during the transportation of the sample as described above. Play.

[Brief description of drawings]

 FIG. 1 is a system diagram showing the overall schematic configuration of the present invention. 1 ... Carbon content measuring device, 2 ... Sample supply pump (sample supply means), 8 ... Pressurization pump (water supply means), 9 ... Reactor, 10 ... Extractor, 11 ... Infrared analyzer ( Measuring method), 18 ... Aperture.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Terumi Iwata 4309-1-401, Akuwa-cho, Seya-ku, Yokohama-shi, Kanagawa Prefecture (72) Inventor Chiaki Mae Koya 4026 Kuji-machi, Hitachi-shi, Ibaraki Hitachi Research Co., Ltd. In-house

Claims (1)

[Claims] 1. A sample containing organic carbon and a reaction solution mixed in the sample are supplied, and the sample and the reaction solution are reacted at high temperature and high pressure to oxidize and decompose the organic carbon. A reactor for producing carbon dioxide, a measuring means for detecting the amount of carbon dioxide produced in the reactor, and a reaction pipe between the sample and the reaction liquid which are drawn into the reactor, And a pipe forming a transport pipe for feeding the sample after the reaction from the reactor to the measuring means, and a portion of the pipe forming the reaction pipe that is connected to the transport pipe. A carbon content measuring device characterized in that a narrowed portion is formed in the vicinity of.