JP2566901Y2 - Online moisture analyzer - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for analyzing the moisture of a liquefied gas on-line, and more particularly to an automatic moisture analyzer using a Karl-Fuscher reagent.

[0002]

2. Description of the Related Art A water measurement method in which titration is performed using a Karl Fischer reagent (hereinafter, referred to as a KF reagent) is capable of measuring water in a liquid sample with high accuracy.
It has been adopted as a legal moisture measurement method such as JIS, ASTM, and DIM. As an automatic moisture measuring device using a KF reagent, as described in, for example, Japanese Utility Model Application Laid-Open No. 60-51459, a liquid sample is taken out of a sample container to a sample quantitative measuring section by a suction device, and the sample quantitative measuring is performed with a solvent. A method is adopted in which the sample inside is extruded into a titration container while the part is washed, and the water content in the titration container is measured by titration with a KF reagent.

[0003] Since titration with a KF reagent cannot be directly performed in the measurement of water content in a liquefied gas sample, the liquefied gas sampled with a pressure-resistant sampler is inserted into a titration container containing a dehydrated solvent with an injection needle to the bottom of a titration container containing 10 to 15 samples. A method of injecting over a minute is performed. The sample vaporized at the same time as the injection is absorbed by the dehydrating solvent and released from the outlet of the container to the outside of the system. The amount of the sample is obtained from the weight difference before and after the injection of the sample, and the water absorbed in the dehydrated solvent is titrated with a KF reagent to calculate the water in the liquefied gas sample.

[0004]

In the Karl Fischer analyzer, an apparatus according to the above-described method for measuring the water content of a liquid sample is commercially available as an automatic analyzer in a laboratory, and is also used for online analysis of industrial equipment. Have been. However, in the case of a liquefied gas sample, it is difficult to automate the above operation, that is, to automatically sample and automatically inject the liquefied gas, and an online automatic moisture measuring device for the liquefied gas that can be used effectively as an industrial device has not yet been obtained. .

The apparatus for measuring the moisture content of a liquefied gas sample according to the above-mentioned method is complicated as it is operated, and has many mechanically operated parts, so that it frequently fails, so that it is suitable as an on-line analyzer for industrial equipment. However, improvement is desired. Liquefied gas on-line moisture analyzers are used for the management of products and intermediates in the manufacturing process of various chemical substances such as dimethyl ether and methyl chloride. Demand is growing. SUMMARY OF THE INVENTION An object of the present invention is to provide a highly accurate and highly stable on-line automatic measuring device which is also used for liquefied gas in moisture measurement of an industrial device.

[0006]

Means for Solving the Problems As a result of intensive studies on the on-line automatic moisture measuring apparatus having the above-mentioned problems, the inventors have collected a liquid sample and / or a liquefied gas in a liquid state online in a sample quantitative measuring section. By injecting the sample into the dehydrating solvent of the titration vessel using a dry gas, it was found that not only liquid samples but also liquefied gas samples can be easily measured for moisture online with a simple device. Reached.

[0007] That is, the present invention provides a liquid or liquid in a manufacturing apparatus.
Uses liquefied gas as an analytical sample online from the device.
Into the titration vessel, and add water using the Karl Fischer reagent.
An analyzer for automatically measuring the amount of a liquid or liquefied gas in a specific amount of a manufacturing apparatus.
To collect samples for analysis online from the
( 2 ) Sample quantitative measurement for collecting a specific amount of analysis sample
Part 3 (c) Airtight titration volume for Karl Fischer analysis
Vessel 9 (d) drying gas for injecting the sample for analysis in titration vessel 9
Introducing section 6 (e) Dehydrating solvent injection for injecting dehydrating solvent into titration vessel 9
Inlet 14 (f) Switching between analysis sample and dehydrated solvent to be injected into titration vessel
Feed switching cock 7 (g) Karl fluoride Shah analyzer 17 for the water content measurement for performing, 及
And (h) a controller 18, which curls the dehydrated solvent from the injector 14.
Controller for injecting into the flasher titration vessel 9
Parts, liquid or liquefied gas in the specified amount of manufacturing equipment
For collecting samples for analysis online from the
Controller, sample collected using dry gas
For injecting into the dehydrating solvent in the titration vessel 9
Dewatered by roller and Karl-Fusher analyzer 17
Titrate the water absorbed by the solvent with Karl Fischer reagent
Online moisture automatic with controls to perform
It is a measuring device.

[0008] The apparatus of the present invention is obtained by modifying a Karl-Fusher analyzer for measuring moisture in a liquid sample, and uses an automatic switching valve to measure a plurality of liquefied gases and the moisture of the liquid sample. Can be. In addition, the collection and quantification of the sample from the process line, the injection of the sample into the titration container, and the introduction into the dry gas sample quantification unit are all performed by the automatic switching valve as shown in the drawings later.

In order to quantify the sample introduced into the moisture measuring device, it is necessary to introduce the sample in a liquid state into the sample quantitative measuring section even if it is a liquefied gas. A pressure regulating valve is installed at the outlet line, and the pressure of the sample quantification unit at the time of sampling is equal to the process pressure. Also, when injecting liquefied gas into the dehydrated solvent, it is necessary to completely absorb the water in the liquefied gas into the dehydrated solvent. It is necessary to gradually inject the sample.

As a gas for injecting into the dehydrating solvent in the titration vessel, a dry gas is used to avoid moisture. The gas used depends on the sample, but usually an inert gas such as nitrogen gas is used. In order to inject the gas into the dehydrated solvent in the titration vessel, it is common practice to pass the gas through silica gel or the like and dry it before introducing the gas into the sample quantitative measurement section.

The dehydrating solvent used for measuring the moisture varies depending on the type of the sample, and for example, methanol is used. The titration container is sealed in order to avoid the influence of the outside air, and usually a dehumidifier such as silica gel is installed in a vent hole with the atmosphere to take measures against air intrusion when discharging waste liquid. The vent hole also serves as a liquefied gas outlet. For the titration with the KF reagent, a stirrer is usually installed inside the titration vessel.

The moisture measuring device of the present invention incorporates a small-sized computer and a sequencer, thereby switching a multi-sample flow path, sampling time, analysis cycle time, discharging waste liquid, injecting a dehydrating agent, titrating KF reagent. In addition, functions such as calculation of moisture concentration, instruction of analysis results, and output of a signal to an external controller can be provided.

The waste liquid after the titration with the KF reagent can be sucked by a pump, but it is advantageous to suck it using an aspirator for the following reasons. Examples of the gas used for suction by the aspirator include pressurized air, the above-mentioned dry gas, and steam. The structure is simple, there is no rotating part, and it is hard to break down.
If excessive suction occurs, no problem occurs. By adjusting the position of the tip of the suction nozzle, an appropriate amount can be left in the titration container. Since it is small and lightweight, the installation place is small. It is cheap.

Next, the present invention will be described with reference to the drawings. FIG.
Is an example of a configuration diagram of an online moisture automatic measuring device according to the present invention.A Karl Fischer analyzer that measures moisture in a liquid sample is modified so that a plurality of liquid samples and liquefied gas samples can be measured by a switching valve. The following shows the device.

The on-line automatic moisture measuring apparatus shown in FIG. 1 includes a part (2 to 16) for introducing and titrating a sample according to the present invention;
The sample multi-channel switching device 1, a commercially available Karl Fischer analyzer 17, a controller (sequencer with a computing unit) 18, and a waste liquid discharging device 19 are roughly divided.

First, in the case of a liquid sample, a target sample is selected in the multi-channel switching device 1 and enters the switching cock 2 of the sample quantitative measuring section, and a fixed amount of liquid sample is collected in the sample quantitative measuring section 3. Is done. During sampling, a part of the liquid sample passes through the discharge sample switching cock 4 and the liquid sample return line 5
Is more exhausted. The collected liquid sample is sent to the titration container 9 via the supply liquid switching cock 7 and the liquid sample supply line 8 by the dry gas supplied from the line 6.

In the case of a liquefied gas sample, similarly to the case of a liquid sample, a target sample is selected in the multi-channel switching device 1 and enters the switching cock 2 of the sample quantitative measuring section, and is fixed in the sample quantitative measuring section 3. A quantity of the sample is collected, but a liquefied gas return line 11 provided with a pressure regulating valve 10 is selected in the discharge sample switching cock 4 in order to avoid vaporization in the sample quantitative measuring section. A liquefied gas supply line 13 provided with a minute adjustment valve 12 is used for supply to the titration container 9 by the supply liquid switching cock 7. The tip of this liquefied gas supply line is deeply immersed in the dehydrated solvent solution of the titration vessel 9, and the sample is gradually injected by the minute adjustment valve 12.

Before the sample is introduced, the dehydrating solvent is added to the pipetting device 14 in advance.
From the titration vessel 9. The titration container 9 is sealed by the above-mentioned method in order to avoid the influence of the outside air. After the dehydrating solvent in the container is dehydrated by the KF reagent introduced from the line 15, the sample is introduced by the above-mentioned method.

After the sample is introduced into the titration vessel 9, the KF reagent is introduced from the Karl Fischer analyzer 17 and titration is performed. The end point of the titration with the KF reagent is detected by the platinum electrode 16 and the water content is measured. The titration vessel is usually equipped with an electromagnetic stirrer (stirrer), which is used for sample introduction and titration. After the completion of the titration with the KF reagent, the solution in the titration container is discharged to a waste liquid discharging device 19.
Is discharged by. As described above, an aspirator is used in this waste liquid discharging device.

As described above, the sample multi-channel switching device 1, each switching cock (sample quantitative measuring section 2, discharged sample 4, supply to the titration container 7), the dispenser 14 for the dehydrated solvent, the stirrer of the titration container 9, The operations of the Karl Fischer analyzer 17 and the waste liquid discharging device 19 are all controlled by a sequence program incorporated in the controller 18, and the water content of each sample is automatically measured. The measurement data is sent from a Karl-Fusher analyzer 17 via a controller to an external device as an instruction of the measurement result and a signal to an external controller.

[0021]

[Effect of the Invention] The online moisture automatic measuring device of the present invention has the following characteristics. It is possible to measure the water content of a liquefied gas sample online with high accuracy, which has been difficult in the past. The device of the present invention can be obtained by modifying a conventional Karl Fischer analyzer that measures moisture in a liquid sample,
Used for measuring liquefied gas and liquid samples. By installing the sample multi-channel switching device and the switching cock, the liquefied gas in the multi-channel and the water content of the liquid sample can be measured by a fully automatic method without any manual operation. Since the apparatus of the present invention measures moisture on-line, it can measure a very small amount of moisture with high accuracy without being affected by atmospheric humidity and the like. By outputting the measurement result as a signal from an external controller, it can be used for direct process control to improve the basic unit in the manufacturing apparatus and reduce the energy consumption in the distillation apparatus.

[0022]

[Brief description of the drawings]

FIG. 1 is an example of a configuration diagram of an online moisture automatic measuring apparatus according to the present invention, in which a Karl-Fusher analyzer for measuring moisture in a liquid sample is modified, and a plurality of liquid samples and a liquefied gas sample are switched by a switching valve. Fig. 1 shows an apparatus capable of measuring.

[Explanation of Signs] 1: Sample multi-channel switching device 3: Sample quantification unit 9: Titration container 14: Dehydrated solvent injector 17: Karl Fischer analyzer 18: Controller 19: Waste liquid discharge device

Claims (3)

(57) [Scope of request for utility model registration] A liquid or liquefied gas in a manufacturing apparatus is
Introduced into the titration vessel as an analytical sample online from the instrument
And automatically measure water using Karl-Fusher reagent
An analyzer for the (a) a liquid or liquefied gas in a specific amount of manufacturing apparatus,該装
To collect samples for analysis online from the
( 2 ) Sample quantitative measurement for collecting a specific amount of analysis sample
Part 3 (c) Airtight titration volume for Karl Fischer analysis
Vessel 9 (d) drying gas for injecting the sample for analysis in titration vessel 9
Introducing section 6 (e) Dehydrating solvent injection for injecting dehydrating solvent into titration vessel 9
Inlet 14 (f) Switching between analysis sample and dehydrated solvent to be injected into titration vessel
Feed switching cock 7 (g) Karl fluoride Shah analyzer 17 for the water content measurement for performing, 及
And (h) a controller 18, which curls the dehydrated solvent from the injector 14.
Controller for injecting into the flasher titration vessel 9
Parts, liquid or liquefied gas in the specified amount of manufacturing equipment
For collecting samples for analysis online from the
Controller, sample collected using dry gas
For injecting into the dehydrating solvent in the titration vessel 9
Dewatered by roller and Karl-Fusher analyzer 17
Titrate the water absorbed by the solvent with Karl Fischer reagent
Online moisture automatic with controls to perform
measuring device 2. The sample quantitative measuring section switching cock 2 is connected to
And, interest from (i) a plurality of liquid and / or liquefied gas
Samples can be used as samples for analysis online from manufacturing equipment
Multi-flow switching device 1 for introduction into the quantitative metering section 3, and
And / or (j) a liquefied gas sample return line 11 having a pressure regulating valve 10
And a discharge sample switching switch connected to the liquid sample return line 5.
The controller comprises a plurality of liquid and / or liquefied gas
Sample from the production equipment online
A control section for introducing into the quantitative measurement section 3 , and / or
Or a command to discharge the liquid sample and the liquefied gas sample
The on-line moisture control device according to claim 1, further comprising a control unit.
Dynamic measuring device (3) connected to a Karl-Fusher titration container (9);
And (h) astigmatism for discharging the curl fluoride shear titration vessel 9
It consists of a waste liquid discharge device 19 with a pyrite, and the controller discharges the Karl Fischer titration container 9
2. The control device according to claim 1, further comprising:
Automatic in-line moisture analyzer