JP2007183252A - Cooling system for analyzer, and device and method of gas chromatography - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide cooling system for cooling sample cooling section of analyzer which excels in workability, its running cost is lower, and also precision of its cooling temperature is higher to reduce energy loss. <P>SOLUTION: This is the cooling system for analyzer 10 provided with the sample cooling section (low-temperature trap device 30). It comprises a cylinder 55, a piston 53 reciprocably-arranged inside this cylinder to compartment expansion chamber 58, compressor 51 for compressing orifice gas, air inlet pipe for supplying the above compressed orifice gas to the above expansion chamber (propellant gas line 52), exhaust pipe for discharging the above orifice gas which is adiabatically-expanded to be decompressed by reciprocation of the above piston (low-pressure gas line 54), low-temperature section cooled by the above adiabatically-expanded low-temperature orifice gas (cooling stage 56), and gas supply line 28 which makes heat exchange of the sample coolant gas with the above low-temperature section to be cooled and then supplies the gas to the above sample cooling section. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cooling device for an analyzer for cooling a sample cooling unit provided in a sample analyzer, and also relates to a gas chromatograph device and a gas chromatography method for cooling a sample gas by such a cooling device.

  A number of apparatuses for cooling a sample and analyzing its characteristics and components, such as a gas chromatograph apparatus, a thermal analysis apparatus, and an X-ray diffraction apparatus, are currently provided. These analyzers include a sample cooling unit for cooling the introduced sample gas and the solid or liquid sample loaded therein, and the sample cooling unit is cooled with a low-temperature cooling gas (sample cooling gas). In common.

Specifically, for example, in the case of a gas chromatograph apparatus that detects a trace gas component contained in a sample gas, a gas component collection tube that once collects the trace gas component (target gas component) at a low temperature and collects it (low temperature trap). Is provided as a sample cooling section. In the gas component collection tube, the target gas is liquefied and aggregated by cooling the sample gas to a temperature below the aggregation point of the target gas component, or filled with an adsorbent that makes the adsorptivity to the target gas component good at low temperatures. The target gas component can be adsorbed from the passing sample gas, and both are used to concentrate the target gas component and improve its detection accuracy.
Examples of thermal analyzers include differential thermal analysis (DTA) devices and differential scanning calorimetry (DSC) that analyze the thermal characteristics of samples by measuring the temperature difference and required energy when both the sample and reference material are cooled. In the case of the apparatus, a sample holder for loading a sample substance is provided as a sample cooling unit.
In the case of an X-ray diffractometer that specifies the crystal structure of a sample by measuring the intensity of scattered X-rays, a glass capillary is used to change the sample enclosed in the sample to amorphous or crystalline by heating or cooling. It is common to provide as a sample cooling part.

  In any of these analyzers, the sample cooling unit is usually cooled using a refrigerant such as liquid nitrogen. There are various ways to use the refrigerant, but it can be broadly classified as follows: (i) a method in which the liquid refrigerant is heat-exchanged with the sample cooling part while being liquid, (ii) a method in which the liquid refrigerant is made into a mist and sprayed on the sample cooling part, iii) A method of spraying a low-temperature gas obtained by heating and vaporizing a liquid refrigerant with a heater to the sample cooling unit, and (iv) a method of spraying a low-temperature gas formed by heat exchange of the normal temperature gas with the liquid refrigerant on the sample cooling unit. One can mention.

As an example of the above method (i), for example, Patent Document 1 below describes the invention of a sample (heating) cooling device that supplies a liquid refrigerant to a cooling pipe wound around a furnace body that contains a sample. Patent Document 2 below discloses an invention of a gas chromatograph apparatus that cools the tip of a capillary column by circulating liquid nitrogen as a refrigerant through a pipe.
As an example of the above method (ii), for example, Patent Document 3 below describes an invention of a sample (heating) cooling device including a blowing pipe for blowing a mist refrigerant to a furnace body containing a sample. Patent Document 4 described below describes an invention of a small sample concentrator that concentrates a gas sample by spraying a liquid refrigerant that has been atomized through a metal filter.
As an example of the above method (iii), for example, the following Patent Document 5 describes an invention of a sample temperature control method in which a sample is cooled by a low-temperature gas obtained by heating and vaporizing a liquid refrigerant while performing a predetermined temperature control with a heater. Has been.
As an example of the above method (iv), for example, the following Patent Document 6 describes an invention of a sample concentrating device that blows a gas gas heat-exchanged with liquid nitrogen gas onto a sample introduction part and cools it.

Japanese Patent Laid-Open No. 7-63715 Japanese Patent Laid-Open No. 5-126817 JP-A-7-63716 JP 2004-53571 A JP-A-10-73546 JP 2000-171449 A

  The inventions described in Patent Documents 1 to 6 are common in a system that consumes a refrigerant such as liquid nitrogen as a cold heat source, and continuously supplies the refrigerant when operating such an analyzer. There is a need. In particular, when analyzing a sample for a long time, it is necessary to prepare a large amount of refrigerant in advance. Hereinafter, the amount of liquid nitrogen consumed will be estimated by taking a conventional gas chromatograph apparatus that cools the sample cooling section with a low-temperature nitrogen gas as an example by the method (iv).

  FIG. 4 is a system diagram of a conventional gas chromatograph device 150 including a gas component collecting tube 132 as a sample cooling unit and a cooling device 100 that cools the sample with a low-temperature nitrogen gas. In the cooling device 100, the liquid nitrogen supplied from the liquid nitrogen container 110 is stored in the storage tank 120, and the heat exchanger 122 is immersed therein. The normal temperature nitrogen gas supplied to the heat exchanger 122 through the flow rate adjusting valve 112 is cooled by liquid nitrogen in the storage tank 120 to become low temperature nitrogen gas, sent to the low temperature trap device 130 through the heat insulation pipe 124, and accommodated therein. The gas component collecting tube 132 is sprayed. On the other hand, the gas component collection tube 132 is continuously supplied with a sample gas to be used for component analysis by the gas chromatograph device 150, and is cooled by the sprayed low-temperature nitrogen gas to liquefy a predetermined target gas component. Aggregated or adsorbed by the adsorbent filled in the gas component collecting tube 132 and collected at a high concentration (so-called cold trapping). Furthermore, the collected gas components are heated and desorbed by spraying room temperature nitrogen gas, and the target gas components are converted to a sample gas with a high concentration, and are analyzed by analyzers such as mass spectrometers and flame ionization detectors (Fig. (Not shown) for component analysis.

Here, in a general gas chromatograph apparatus, the temperature of the low-temperature nitrogen gas blown to cool the gas component collecting tube 132 is −120 ° C., and the flow rate is about 15 [L / min]. In the cooling device 100 illustrated in FIG. 4, it takes about 20 cm ³ of liquid nitrogen per minute to cool the room temperature nitrogen gas with liquid nitrogen at −196 ° C. to obtain the above low temperature nitrogen gas. When converted per day, the amount of consumption is about 30 [L / day].

  Accordingly, when the gas chromatograph device 150 is operated while the gas component collecting tube 132 is cooled by the cooling device 100, even if a large liquid nitrogen container 110 (the internal capacity is generally about 170 L) is used, it is 4 to 4. This needs to be changed every 5 days. However, since the large liquid nitrogen container 110 filled with liquid nitrogen has a total weight of 250 kg, dedicated equipment and personnel are required for carrying it into the test facility where the gas chromatograph device 150 is placed and for replacing the container. In addition, it requires a lot of work time and is inferior in workability, and it is not easy to always store and manage such a large liquid nitrogen container 110.

  On the other hand, when using a small liquid nitrogen container (with an internal capacity of about 30 L in general) having excellent handling properties, the replacement frequency becomes extremely high, and it is compulsory to perform one or more replacement operations every day. It was. In recent years, gas chromatographs that automatically supply a large number of sample gases of about 60 to 70 and analyze them continuously have appeared, and in order to enable continuous operation of the cooling device for several days. The above-mentioned small container is not sufficient, and it is necessary to prepare a large container filled with liquid nitrogen.

  Further, in the conventional cooling device 100 that consumes a refrigerant such as liquid nitrogen, it is necessary to replenish the refrigerant each time, which increases the running cost.

Furthermore, since the vaporization temperature of a refrigerant such as liquid nitrogen is constant for each refrigerant substance at the same pressure, the cooling temperature of the sample cooling unit depends on the aggregation point temperature, phase transition temperature, etc. of the sample applied to the analyzer. There is another problem that it is not easy to adjust the elevation accurately.
That is, for example, when the vaporization temperature of liquid nitrogen is −196 ° C. at normal pressure, when attempting to cool the sample cooling part of the analyzer to, for example, −50 ° C., (a) in a gas chromatograph device or an X-ray diffraction device, The amount of refrigerant sprayed onto each gas component collection tube or glass capillary is appropriately controlled by opening or closing a valve, etc. (a) In a thermal analyzer, a heater and thermometer are attached to the sample holder while adjusting the heating. It is usual to cool with a refrigerant. However, in the case of (a) above, it is difficult to attach a thermometer to the gas component collection tube or the glass capillary because of its construction, so accurate temperature control cannot be performed, and the analysis result by the analyzer is not observed. However, it takes a long time to readjust the valve opening / closing amount. In the case of (b), the heater is installed in the sample cooling section, which makes the system configuration complicated, and the heater is heated while the sample cooling section is excessively cooled with a low-temperature gas (sample cooling gas). When the loss is large and the temperature difference between the sample cooling gas temperature and the target cooling temperature is large, there is a problem that accurate temperature control is difficult.

  These problems do not occur only in the cooling device 100 based on the cooling method (iv) shown in the system diagram of FIG. 4, but the sample cooling unit uses the refrigerant in the methods (i) to (iii). The same applies to the case of cooling.

  As described above, in the conventional analyzers, since a cooling medium such as liquid nitrogen is used for cooling the sample cooling section, a great deal of work and cost are required for the container replacement that frequently occurs as the exhaustion occurs. There are also many problems from the viewpoint of controlling the cooling temperature of the sample cooling section and from the viewpoint of energy loss.

  Based on the above, the present invention provides a cooling device that cools the sample cooling section of the analyzer, which is excellent in workability, low in running cost, high in temperature accuracy of cooling temperature, and low in energy loss. The main purpose. Another object of the present invention is to provide a gas chromatograph capable of suitably performing component analysis of a sample gas as an analyzer that cools a sample cooling section with such a cooling device. Other objects of the present invention will become apparent from the following description.

  The cooling device according to the present invention does not cool the sample cooling part of the analyzer using a refrigerant having a constant vaporization temperature, but cools the low temperature part of the refrigerator adjusted in advance according to the target cooling temperature. And the sample cooling gas are heat-exchanged to cool the sample cooling gas and used for cooling the sample cooling unit.

That is, the cooling device for an analyzer according to the present invention is
(1) A cooling device for an analyzer having a sample cooling unit,
A cylinder,
A piston which is provided inside the cylinder so as to be capable of reciprocating and forms an expansion chamber;
A compressor for compressing the working gas;
An air supply pipe for supplying the compressed working gas to the expansion chamber;
An exhaust pipe that discharges the working gas adiabatically expanded by the reciprocating motion of the piston, and
A low temperature part cooled by the adiabatic expanded low temperature working gas;
A gas supply pipe for supplying the sample cooling gas to the sample cooling unit after cooling the sample cooling gas by heat exchange with the low temperature unit;
A cooling device for an analyzer having
(2) The supply pipe is provided with a branched introduction pipe for extracting a part of the working gas supplied to the expansion chamber and introducing it into the gas supply pipe as the sample cooling gas, and
The exhaust pipe is provided with a reflux pipe for recirculating the sample cooling gas supplied to the sample cooling section as a working gas;
(3) The analysis according to (1) or (2), further including heat exchange means for exchanging heat between the sample cooling gas after cooling the sample cooling portion and the sample cooling gas before being cooled at the low temperature portion. Cooling device for equipment;
Is the gist.

Further, the gas chromatograph apparatus and the gas chromatography method according to the present invention include:
(4) The sample gas introduced into the sample cooling unit is cooled with the sample cooling gas supplied from the analyzer cooling device according to any one of (1) to (3), and is included in the sample gas. Gas chromatograph apparatus for collecting gas components to be collected;
(5) In a gas chromatography method for cooling a sample gas and collecting a gas component contained in the sample gas,
A gas chromatography method comprising: exchanging heat between a normal temperature gas and a low temperature part of a refrigerator to generate a low temperature sample cooling gas; and cooling the sample gas with the sample cooling gas;
(6) A part of the working gas is extracted from the refrigerator to obtain the normal temperature gas, and the sample cooling gas obtained by cooling the sample gas is returned to the refrigerator to obtain the working gas. A gas chromatography method according to claim 1;
Is the gist.

According to the cooling device for an analyzer according to the present invention, since a low-temperature sample cooling gas is generated by heat exchange with a refrigerator without using a refrigerant such as liquid nitrogen, When management is necessary, this becomes unnecessary, and the workability and running cost are excellent.
Further, since replenishment of the refrigerant is unnecessary, there is no limitation on the operation time, and the analyzer can be operated without stopping for a long time.

Further, according to the present invention, the temperature of the sample cooling gas can be adjusted up and down freely by adjusting the output of the refrigerator, so that the sample cooling gas whose temperature is set according to the cooling target of the sample cooling unit is supplied. Therefore, as compared with the conventional case where it is excessively cooled with the sample cooling gas and heated with the heater, the generation of energy loss can be greatly suppressed and the temperature accuracy is improved.
This is remarkable when the cooling target temperature of the sample cooling unit is relatively high. For example, in the case where this is set to −50 ° C. as described above, in order to cool the sample cooling section using liquid nitrogen having a vaporization temperature of −196 ° C. as a refrigerant, about 150K from the vaporization temperature by the heater. Because it is necessary to increase the temperature strongly, the temperature of the sample cooling part inevitably involves large overshoots and undershoots, and the temperature of the sample cooling part varies greatly due to fluctuations in the flow rate of the sample cooling gas. For this reason, it is extremely difficult to accurately control the temperature to the set cooling target temperature. On the other hand, according to the present invention, for example, when a general regenerative refrigerator is used as a refrigerator, the temperature error of the low temperature portion is suppressed to within a few K at most, so that sufficient heat exchange is performed with this. By supplying the cooled sample cooling gas to the sample cooling section, the temperature can be controlled extremely stably and accurately.

  Therefore, according to the gas chromatograph apparatus that cools the gas component collection pipe (sample cooling section) with the sample cooling gas supplied by the cooling apparatus according to the present invention, the workability and running cost are excellent, and the operation time is not limited. Furthermore, because the accuracy of the cooling temperature of the gas component collection tube is high, the target gas component can be efficiently separated from a large number of gas components by utilizing the difference in the boiling point temperature of the gas component and the difference in the adsorptivity to the adsorbent. , Accurate detection becomes possible.

  Further, in the cooling device according to the present invention, as a more specific aspect, the introduction pipe for extracting a part of the working gas supplied to the expansion chamber and introducing it into the gas supply pipe as the sample cooling gas is branched to the supply pipe. In addition, a reflux pipe that refluxes the sample cooling gas supplied to the sample cooling unit as a working gas may be provided in the exhaust pipe. With this configuration, the sample cooling gas (normal temperature gas) from which a part of the working gas has been extracted from the supply pipe is heat-exchanged at the low temperature portion of the cooling device to be converted into low temperature gas, and further, After being used for cooling, it is returned to the exhaust pipe as working gas. As a result, the sample cooling gas (room temperature gas, low temperature gas) circulates in the closed cycle, so that it is not consumed, and for example, nitrogen gas is generated from the outside of the cooling device as the material for the sample cooling gas. Since it is not necessary to supply constantly using gas supply means, such as an apparatus and a gas container, the installation space and running cost can be reduced.

  In the cooling device according to the present invention, as a more specific aspect, heat for exchanging heat between the sample cooling gas after cooling the sample cooling portion and the sample cooling gas before being cooled at the low temperature portion of the cooling device. An exchange means may be provided. With this configuration, the sample cooling gas (room temperature gas) that is heat-exchanged with the low-temperature part is cooled in advance, and the amount of heat of the sample cooling gas to be removed from the low-temperature part is reduced, thus reducing the load on the cooling device. can do.

  The best mode for carrying out the present invention will be specifically described below with reference to the drawings. FIG. 1 is a front view of the cooling device 10 according to the first embodiment of the present invention, and shows a state in which a cover 24 and a casing 26 are partially cut away.

  The cooling device 10 cools a normal temperature gas by heat exchange between the cooling stage 56 and a regenerative refrigerator 50 that obtains a low temperature in the cooling stage (low temperature part) 56 by adiabatic expansion of the working gas, and a low temperature gas (sample cooling gas). And a gas supply pipe 28 for supplying to the gas component collection pipe (sample cooling section) of the analyzer.

As an analyzer, a gas, a liquid, or a solid sample is cooled by a sample analyzer and analyzed for its components and physical properties. For example, a gas chromatograph (gas chromatograph-infrared spectrometer) can be used. And a gas chromatograph-mass spectrometer), a thermal analyzer (including a differential thermal analyzer, a differential scanning calorimeter, a thermogravimetric analyzer), an X-ray diffractometer, and the like.
Examples of the sample cooling unit include a gas component collection tube of a gas chromatograph device, a sample holder of a thermal analysis device, and a glass capillary of an X-ray diffraction device.

  The gas supply pipe 28 derives the gas introduction pipe 42 that introduces room temperature gas, the heat exchange unit 22 that exchanges heat between the cooling stage 56 and the room temperature gas, and the room temperature gas cooled by the heat exchange unit 22, that is, the low temperature gas. A gas outlet pipe 62.

  The gas outlet pipe 62 through which the low temperature gas flows is covered with a vacuum heat insulating pipe 60 outside the housing 26 in order to prevent the low temperature gas from being heated by the ambient temperature. The gas outlet pipe 62 and the vacuum heat insulating pipe 60 can be obtained by fitting flexible tubes having two large and small diameters to each other, vacuum insulating between the two, and further applying a radiant heat shield. In this case, the inner small diameter tube corresponds to the gas outlet tube 62, and the outer large diameter tube corresponds to the vacuum heat insulating pipe 60.

The regenerative refrigerator 50 includes a cylindrical cylinder 55, a piston 53 that is provided in the cylinder 55 so as to reciprocate and that defines an expansion chamber 58, and a compressor 51 that compresses the working gas (see FIG. 2). And a supply pipe (high-pressure gas pipe) 52 (see FIG. 2) for supplying the working gas compressed by the compressor 51 to the expansion chamber 58 and a reciprocating motion of the piston 53 to reduce the pressure. An exhaust pipe (low-pressure gas pipe) 54 (see FIG. 2) that discharges the working gas and a cooling stage 56 that is cooled by the adiabatically expanded low-temperature working gas. The piston 53 is filled with a cool storage material 59 and has a communication hole communicating with the cooling stage 56. The supply gas of the working gas to the expansion chamber 58 through the high pressure gas pipe 52 and the exhaust of the working gas from the expansion chamber 58 through the low pressure gas pipe 54 are sequentially switched by the switching unit 57. The cooling stage 56 is gradually cooled. A specific description of the principle of generating a low temperature in the expansion chamber 58 by adiabatic expansion of the working gas will be described later.
The cooling stage 56 is also called a cold head. Specifically, a metal material having good thermal conductivity such as copper is provided in thermal contact with the tip of the expansion chamber 58 (the lower end in FIG. 1). The low temperature of the working gas generated in the chamber 58 can be taken out of the cylinder 55. Further, the outer surface of the expansion chamber 58 may correspond to the cooling stage 56, or in addition, the expansion chamber 58 and the cooling stage 56 may be in thermal contact with each other through a cool storage material exposed in the expansion chamber 58. Good.

  The regenerative refrigerator having the above-described configuration is a compact and space-saving cylinder with a length of about 500 mm, a weight of about 10 kg, light handling and good handling characteristics, and power consumption of about several kW and low running cost. Is provided.

  The cover 24 that covers the cooling stage 56 is made of a metal material having good thermal conductivity, and is provided in thermal contact with the cooling stage 56, so that it is cooled together with the cooling stage 56 by adiabatic expansion of the working gas.

  The heat exchanging unit 22 that cools the normal temperature gas to generate a low-temperature sample cooling gas has a function of directly or indirectly heat-exchanging the normal temperature gas with the cooling stage 56. Specifically, in the case of the cooling device 10 according to the present embodiment, the inner surface of the cover 24 is hermetically sealed, and is introduced from the gas introduction pipe 42 into a space (heat exchange region) surrounded by the cover 24 and the cooling stage 56. The normal temperature gas is blown out and brought into direct contact with the cooling stage 56 and the inner surface of the cover 24. In addition, in the present invention, the gas introduction pipe 42 may be wound around the cooling stage 56 in a coil shape, and the normal temperature gas and the cooling stage 56 may be indirectly heat-exchanged via the gas introduction pipe 42. Further, the cooling stage 56 and the normal temperature gas or the gas introduction pipe 42 may be brought into thermal contact with each other through a heat exchanger in which a heat medium is sealed. Further, in the present invention, the cover 24 cooled by the cooling stage 56 forms a part of the heat exchanging section 22, so that it is wound around the normal temperature gas once opened in the heat exchanging region or the cooling stage 56. In addition, a wide contact area between the gas introduction pipe 42 and the heat exchange unit 22 can be secured. In order to prevent low temperature dissipation from the outer surface of the cover 24, the internal space of the casing 26 is vacuum insulated.

  A regenerative refrigerator 50 whose configuration is shown in FIG. 1 relates to a Gifford McMahon refrigerator (GM refrigerator), but in the present invention, in addition to this, a Stirling refrigerator, a pulse tube refrigerator, a Wilmier refrigerator, and a Solvay refrigerator. A refrigerator or the like can be used as the regenerative refrigerator 50. All of these refrigerators are commercially available, and the cooling stage 56 can be cooled to an extremely low temperature of −200 ° C. or lower by using a gas having a low boiling point temperature such as helium or nitrogen as a working gas.

  Note that the regenerative refrigerator 50 used in the present embodiment may be provided with the compressor 51, the cylinder 55, and the cooling stage 56 in multiple stages in order to obtain a lower temperature in the cooling stage 56.

Nitrogen, helium, argon, other inert gases, or dry air is suitably used as the room temperature gas that is heat-exchanged by the regenerator type refrigerator 50. In addition, normal temperature as used in this invention shall mean the temperature between 20 +/- 15 degreeC.
The dry air can be obtained simply by adsorbing and removing water vapor from the ambient air with silica gel or the like using a small-sized drying apparatus having excellent handling properties. Alternatively, a commercially available nitrogen gas generator may be used to adsorb oxygen gas, carbon dioxide gas, moisture, etc. from atmospheric air to obtain nitrogen gas having a high purity and a low dew point, and this may be used as room temperature gas. By removing water vapor that solidifies at 0 ° C. at atmospheric pressure and carbon dioxide that solidifies at about −79 ° C. from the ambient air, the refrigerating refrigerator 50 is prevented from freezing at these temperatures, while at lower temperatures. A sample cooling gas can be obtained.
As described above, according to the cooling device 10 according to the present invention, the liquid refrigerant is not necessary for generating the low-temperature sample cooling gas, and thus the effects of the present invention can be achieved.

FIG. 2 is a system diagram of the gas chromatograph device 15 including the cooling device 10 according to the second embodiment of the present invention and a gas component collection tube (sample cooling unit) 32.
The cooling device 10 includes the regenerator type refrigerator 50 shown in FIG. 1, the vacuum chamber 20 having airtightness and heat insulation that accommodates the cooling stage 56 of the regenerator type refrigerator 50, and the nitrogen gas generator 40. A room temperature gas supply pipe (gas introduction pipe) 42 for introducing the generated room temperature nitrogen gas into the vacuum chamber 20, a heat exchange section 22 in which the room temperature gas supply pipe 42 is wound around a cooling stage 56 in a coil shape, and a heat exchange section 22 And a low-temperature gas supply pipe (gas outlet pipe) 62 for extracting the low-temperature sample cooling gas cooled by heat exchange in the vacuum chamber 20 and supplying it to the gas component collecting pipe 32.

The regenerative refrigerator 50 used in the present invention uses nitrogen gas, helium gas, or the like having a low aggregation temperature and high safety as a working gas. The working gas is introduced into the compressor 51 from the low-pressure gas pipe (exhaust pipe) 54, where it is compressed to a high pressure and sent to the high-pressure gas pipe (supply pipe) 52. The compression ratio by the compressor 51 is usually about 2 to 3 times, but is not limited thereto. In general, the pressure of the working gas flowing through the low-pressure gas pipe 54 is set to normal pressure or higher, and the pressure of the working gas flowing through the high-pressure gas pipe 52 is set to a high pressure exceeding this. The pressure of the working gas flowing through the low-pressure gas pipe 54 can be set to a normal pressure or lower, but is not limited thereto.
On the other hand, the temperature of the working gas flowing through the low-pressure gas pipe 54 is room temperature, and the working gas is compressed even when being sent to the high-pressure gas pipe 52 by being compressed by the compressor 51 while being cooled by cooling water or the like. The room temperature is maintained. However, the temperature of the working gas flowing through the high-pressure gas line 52 or the low-pressure gas line 54 can be higher or lower than normal temperature (20 ± 15 ° C.).

  The high-pressure working gas flowing through the high-pressure gas conduit 52 is introduced into the cylinder 55 via the switching unit 57. A cylindrical piston 53 filled with a cold storage material is slidably provided inside the cylinder 55. The piston 53 is provided with a communication hole that allows the switching unit 57 and the cooling stage 56 to communicate with each other. The high-pressure working gas introduced into the cylinder 55 is stored in the cooling stage 56 through the communication hole while being heat-exchanged with the cold storage material and cooled to a predetermined temperature. Next, in a state where the communication hole is closed by the operation of the switching unit 57, the temperature of the working gas is further reduced by adiabatic expansion of the high-pressure working gas stored in the cooling stage 56, and the cooling capacity is reduced by the cooling stage 56. Is obtained. Further, the switching unit 57 is switched to open the communication hole to the low-pressure gas pipeline 54, and the working gas expanded to a low temperature and low pressure is discharged from the switching unit 57 to the low-pressure gas pipeline 54 while exchanging heat with the cold storage material. . As a result, a step of introducing a high-pressure working gas from the high-pressure gas line 52 to the cooling stage 56 through the cylinder 55 and expanding it, and a working gas that has been expanded to a low pressure into the low-pressure gas line 54 through the cylinder 55. The steps of discharging and sending to the compressor 51 are alternately repeated, so that the cooling stage 56 can be gradually cooled.

  In the regenerative refrigerator 50, the temperature of the cooling stage 56 can be arbitrarily adjusted in the range of the normal temperature or lower and the lowest temperature or higher by changing the stroke of the piston 53 and the number of reciprocations per unit time. The temperature accuracy can be at most several [K] or less. For this reason, for example, compared with a conventional cooling device that controls the temperature to, for example, −100 ° C. or −50 ° C. by heating the heater while cooling the sample cooling unit using liquid nitrogen having a vaporization temperature of −196 ° C. as a refrigerant, The temperature accuracy of the sample cooling gas can be made extremely high.

  In this embodiment, when the temperature accuracy of the sample cooling gas supplied to the sample cooling unit such as the low temperature trap apparatus 30 is further improved, the cooling stage 56 and heat exchange are performed in the vacuum chamber 20 as shown in FIG. A heater 72 may be attached to the section 22 or the low temperature gas supply pipe 62 to heat them. The temperature controller 70 can raise and lower the output of the heater 72, monitors the temperature of the sample cooling gas with a temperature sensor (not shown), and adjusts the heater output by open loop control to accurately adjust the temperature of the low temperature gas. It can be controlled well. In the present invention, since the temperature of the cooling stage 56 can be brought close to the target temperature of the sample cooling gas by adjusting the output of the regenerative refrigerator 50, the sample cooling gas can be provided even if the heater 72 is provided as in the present embodiment. The amount of heat applied to the heat sink is very small, and the energy loss that is significant in the conventional cooling device is greatly suppressed.

  Further, the low-temperature gas supply pipe 62 that circulates the sample cooling gas that has been temperature-adjusted with high accuracy is not covered with the atmosphere, as shown in FIG. Yes.

  The room temperature gas supply pipe 42 is provided with a flow rate adjusting valve 44 between the nitrogen gas generator 40 and the vacuum chamber 20, and controls the flow rate of the room temperature nitrogen gas cooled by the regenerative refrigerator 50 to a predetermined amount. ing. The flow rate adjusting valve 44 is a valve that keeps the pressure difference between the primary side and the secondary side of the valve constant by, for example, a diaphragm and a spring and allows a predetermined gas flow rate to pass stably, and a commercially available one can be used. However, the type of the flow rate adjusting valve 44 is not limited to the above. Further, a low temperature gas supply valve 45 is provided between the nitrogen gas generator 40 and the flow rate adjustment valve 44 so that the generation of the low temperature gas and the cooling of the sample gas by the low temperature gas can be started, stopped or restarted instantaneously. .

  The cryogenic trap device 30 is a device that cools a sample gas and collects a gas component (target gas component) for component analysis by gas chromatography at a low temperature. The thermostatic chamber 36, a gas component collecting tube ( (Sample cooling unit) 32 and a collecting tube cooling means.

  In the present embodiment shown in FIG. 2, as a collecting pipe cooling means, a low temperature gas outlet 37 that blows a low temperature gas (sample cooling gas) transferred by a low temperature gas supply pipe 62 toward the gas component collection pipe 32. Is used.

A part of the gas component collecting pipe 32 is accommodated in the thermostatic chamber 36, and the sample gas is introduced from the upstream side in the direction of the arrow in the figure. The sample gas is cooled by blowing low temperature gas from the low temperature gas outlet 37 in the first half of the trap portion 34 of the gas component collecting pipe 32. The trap part 34 is formed by bending the gas component collecting pipe 32 in a loop shape, and by extending the passage time of the sample gas, the trap part 34 is sufficiently cooled by the low temperature gas, so that a small amount of the object contained in the sample gas can be obtained. The gas component can be liquefied and aggregated.
In addition, by adjusting the temperature and flow rate of the low temperature gas blown out from the low temperature gas outlet 37 and cooling the temperature inside the trap part 34 to a predetermined temperature not higher than the boiling point of the target gas component, the boiling point higher than this temperature is obtained. The gas component (including the target gas component) having liquefaction can be liquefied and aggregated in the trap portion 34. In particular, by making the temperature inside the trap part 34 coincide with the boiling point temperature of the target gas component, only the target gas component and the gas component having a higher boiling point temperature are liquefied and aggregated in the trap part 34 and collected. Can do.

  In addition, the trap part 34 is filled with an adsorbent that adsorbs the target gas component, and the internal temperature of the trap part 34 is set to a predetermined temperature equal to or higher than the boiling point temperature of the target gas component (for example, the boiling point temperature +20 to The target gas component can also be adsorbed and collected by cooling to 30 ° C. Also in this case, the target gas component can be efficiently collected by adjusting the temperature and flow rate of the low temperature gas.

  The gas component (mixed gas component) collected at a high concentration by aggregation or adsorption in the trap part 34 is heated by means such as blowing nitrogen gas at room temperature, and is desorbed from the trap part 34 to obtain a high concentration sample gas. And is sent from the gas component collecting pipe 32 to a separation column (not shown). Such heating of the trap unit 34 may be performed simultaneously with the spraying of the low temperature gas, or may be performed after the low temperature gas supply valve 45 is shut off and the supply of the low temperature gas is stopped. Here, when the target gas component is liquefied and aggregated and collected, it is the gas component having the lowest boiling point among the liquefied and aggregated mixed gas components, that is, easily vaporized, by gently heating the trap portion 34. The target gas component can be desorbed. In this case, in addition to the target gas component, a gas component having a boiling point very close to the target gas component is also vaporized, but these gas components can be separated by a separation column described later. On the other hand, a sharper peak can be obtained in gas chromatography by heating the trap part 34 rapidly. Note that the separation column may be accommodated inside the thermostat 36 or provided outside the thermostat 36.

  As a method of gently heating and desorbing the collected target gas component, the trap part 34 is heated by a heater or a heat medium in addition to the above-described method in which a desorption gas such as room temperature nitrogen gas is blown from the room temperature gas outlet 38. May be. FIG. 2 illustrates an embodiment in which normal temperature nitrogen gas is supplied to the normal temperature gas outlet 38 through the desorption gas supply pipe 80. The nitrogen gas supplied to the room temperature gas outlet 38 can be room temperature nitrogen gas generated by the nitrogen gas generator 40. That is, in this case, it is preferable that the room temperature gas supply pipe 42 is branched between the nitrogen gas generator 40 and the vacuum chamber 20 and connected to the desorption gas supply pipe 80. In addition, it is preferable that a flow rate adjusting valve is provided in the desorption gas supply pipe 80 to appropriately adjust the heating rate of the trap portion 34.

  In the separation column installed downstream of the gas component collection pipe 32, the target gas component desorbed by heating and a plurality of gas components close to the boiling point temperature or the adsorbent are adsorbed and the difference in adsorbability to the column is obtained. After further separation using physical properties such as the above, it is sent to an analyzer (not shown) such as a mass spectrometer or a flame ionization detector for component analysis.

  The low temperature gas blown out from the low temperature gas outlet 37 and the normal temperature desorbed gas blown out from the normal temperature gas outlet 38 are mixed inside the thermostat 36 to become a mixed gas having a temperature lower than the normal temperature. In the present embodiment, since nitrogen gas is used for both the low temperature gas and the desorption gas, the exhaust gas discharged from the thermostatic chamber 36 is nitrogen gas at an intermediate temperature between the low temperature gas and the desorption gas.

  Such exhaust gas may be exhausted from the thermostat 36 to the outside of the gas chromatograph device 15, but is supplied by the nitrogen gas generator 40 by returning a part or all of the exhaust gas to the room temperature gas supply pipe 42. The amount of nitrogen gas to be reduced can be reduced. In this case, since nitrogen gas (exhaust gas) lower than normal temperature is supplied to the normal temperature gas supply pipe 42, the amount of heat to be exchanged by the regenerative refrigerator 50 is reduced, and the consumption of the regenerative refrigerator 50 is reduced. Electric power can be reduced.

  Further, even when the exhaust gas is not recirculated to the room temperature gas supply pipe 42, the low temperature of the exhaust gas is used to thermally connect the gas discharge pipe 82 and the room temperature gas supply pipe 42 by the heat exchange unit 84 as shown in FIG. The room temperature nitrogen gas supplied from the nitrogen gas generator 40 is cooled and the power consumption of the regenerative refrigerator 50 can be reduced. This is particularly suitable when the low temperature gas and the desorption gas are different types of gas and the exhaust gas cannot be recycled to the normal temperature gas supply pipe 42 and reused as the low temperature gas. Specifically, the heat exchanging part 84 may be configured to wind the gas discharge pipe 82 around the room temperature gas supply pipe 42 to increase the contact area between the two, or may be brought into thermal contact with each other by a heat exchanger. The exhaust gas that has cooled the room temperature nitrogen gas in the heat exchanging unit 84 has recovered to a temperature of about room temperature, and is exhausted from the gas exhaust port 86 to the outside of the gas chromatograph device 15.

  The gas chromatograph apparatus 15 according to the present embodiment can control the temperature of the low temperature gas blown from the low temperature gas outlet 37 toward the trap section 34 within a predetermined range. There are various methods for controlling the temperature of the low-temperature gas. In addition to the method of heating the cooling stage 56, the heat exchanging unit 22, or the low-temperature gas supply pipe 62 using the heater 72 described above, a heater is provided at the low-temperature gas outlet 37. (Not shown) may be attached and heated.

  It is preferable to control the temperature of the low temperature gas blown out from the low temperature gas outlet 37 within a range of −200 ° C. to −50 ° C. If helium gas, for example, is used as the working gas for the low temperature gas and the regenerator refrigeration machine 50 and the temperature of the cooling stage 56 of the regenerator refrigeration machine 50 is set to a very low temperature of, for example, about -270 ° C. It is possible to control the temperature of the low temperature gas to -200 ° C. Thereby, when nitrogen gas (boiling point in normal pressure: -196 degreeC) is contained in sample gas, this can be cooled to boiling point temperature and can also be liquefied and aggregated. On the other hand, by making temperature control possible to −50 ° C. on the high temperature side, most of organic target gas components can be sufficiently liquefied and aggregated. In addition, even when the target gas component is adsorbed and collected by the adsorbent, the adsorbability of the target gas component is improved by accurately controlling the temperature of the sample gas by selecting one of the above temperature ranges. be able to. In addition, by making the preset temperature of the low temperature gas as high as possible, the load on the regenerator chiller 50 can be reduced and the power consumption can be reduced.

In the gas chromatograph apparatus 15 according to the present embodiment, it is preferable to control the temperature of the low temperature gas by selecting a suitable temperature from the above temperature range according to the boiling point temperature and flow rate of the target gas component. .
Further, for the purpose of sufficiently collecting the target gas component in the trap part 34 of the gas component collecting pipe 32, the internal temperature of the thermostatic chamber 36 is appropriately selected, and the room temperature nitrogen gas passing through the flow rate adjusting valve 44 is selected. It is also preferable to control the flow rate and switch between blowing out the low temperature gas and blowing out the desorption gas with good timing.

In the gas chromatography method and the gas chromatograph apparatus according to the present invention, a method is employed in which a normal temperature gas is heat-exchanged to generate a low temperature gas having a desired temperature, and the gas component collecting tube 32 is cooled by the low temperature gas. For this reason, the temperature of the low temperature gas is accurately adjusted according to parameters such as the flow rate, pressure, specific heat, temperature of the sample gas introduced into the gas component collecting pipe 32, or the boiling point temperature or content of the target gas component to be contained. And can be adjusted without energy loss.
By making this adjustment possible, the target gas component can be collected, separated and adsorbed by the most efficient liquefaction aggregation or adsorption, so the sensitivity of the analyzer to the target gas component and the separation accuracy of the target gas component And the analysis accuracy can be improved.

  In addition, it is suitable to use the same kind of gas as the low temperature gas or a mixed gas of a gas having a lower boiling point than the low temperature gas and the low temperature gas as the working gas of the regenerator type refrigerator 50. Thereby, even when the normal temperature gas is cooled to the vicinity of its boiling point temperature to obtain a low temperature gas, the normal temperature gas is liquefied and condensed or solidified in the cooling stage 56 of the regenerative refrigerator 50, and a desired low temperature gas flow rate is obtained. Can be avoided, or the heat exchange unit 22 can be clogged. Specifically, when helium gas (boiling point at normal pressure: about −269 ° C.) is mainly used as the working gas of the regenerative refrigerator 50 and nitrogen gas (boiling point at normal pressure: about −196 ° C.) is used as the normal temperature gas. Even if the output of the regenerative refrigerator 50 is not specifically controlled by mixing a small amount of nitrogen gas with the working gas, for example, when the working gas on the low pressure side is normal pressure, the cooling stage 56 is set to −196 ° C. The output of the regenerative refrigerator 50 decreases when the cryogenic temperature is reached. For this reason, it is avoided that the normal temperature gas is cooled to the boiling point temperature or less and is aggregated or solidified, and the low temperature gas is stably blown out without decreasing the flow rate of the low temperature gas blown out from the low temperature gas outlet 37. 30.

  FIG. 3 shows a gas chromatograph apparatus 15 including a cooling apparatus 10 according to a third embodiment of the present invention and a low-temperature trap apparatus 30 containing at least a part of a gas component collection tube (sample cooling section) 32. A system diagram is shown. The cooling device 10 according to the present embodiment is characterized in that a part of the working gas of the regenerative refrigerator 50 is used as a low-temperature gas (sample cooling gas) for cooling the gas component collecting pipe 32.

  That is, the regenerative refrigerator 50 causes the high-pressure working gas and the low-pressure working gas to be alternately switched between the compressor 51 and the switching unit 57 and continuously adiabatically expanded in the cooling stage 56. In this embodiment, a part of the working gas on the high-pressure side is extracted and cooled by the cooling stage 56, and the gas component collecting tube is obtained. 32 is a low temperature gas for cooling. Further, the low-temperature gas used for cooling the gas component collecting pipe 32 is recirculated as a working gas to the low-pressure side of the regenerator type refrigerator 50 again.

  By adopting such a method, the normal temperature gas and the low temperature gas circulate in the closed cycle, so that they are not consumed and the supply of the normal temperature gas from the outside by the nitrogen gas generator 40 or the like becomes unnecessary. Therefore, the installation space for the nitrogen gas generator 40 and the running cost can be further reduced.

A specific configuration of the cooling device 10 according to the present embodiment will be described below.
Helium gas is used as the working gas for the normal temperature gas, the low temperature gas, and the regenerative refrigerator 50. However, nitrogen gas or a mixed gas of helium gas and nitrogen gas may be used.

A high-pressure gas pipe (supply pipe) 52 that communicates between the compressor 51 and the switching unit 57 is provided by branching the room temperature gas supply pipe 42 as an introduction pipe at a high-pressure side branching section 91 in the middle. The normal temperature gas supply pipe 42 is wound around the cooling stage 56 of the regenerator refrigerator 50 to form a first heat exchange unit 95. In the first heat exchanging portion 95, in addition to the method of indirectly exchanging heat between the normal temperature gas and the cooling stage 56 as shown, in the space (heat exchanging region) surrounding the cooling stage 56 as shown in FIG. A system in which the normal temperature gas is once released and the two are directly subjected to heat exchange may be used.
A part of the room temperature and high pressure helium gas sent out from the compressor 51 and flowing through the high pressure gas pipe 52 is extracted and enters the room temperature gas supply pipe (introduction pipe) 42 and is introduced into the vacuum chamber 20. The room temperature gas supply pipe 42 is provided with a flow rate adjusting valve 44, and is branched at the high pressure side branching portion 91 by controlling the outlet side pressure of the flow rate adjusting valve 44 and introduced into the room temperature gas supply pipe 42. The ratio of helium gas can be adjusted.

In general, by extracting 1 to 5% of the working gas and generating a low temperature gas, the gas component collecting pipe 32 can be sufficiently cooled to trap the target gas component at a low temperature. 50 is not hindered by the lack of working gas.
The normal temperature gas supply pipe 42 is preferably provided with a check valve (not shown) upstream or downstream of the flow rate adjusting valve 44 to prevent the reverse flow of the normal temperature gas flowing through the inside. Further, when the working gas is nitrogen gas or argon gas, it is also preferable to provide an expansion valve or orifice in the room temperature gas supply pipe 42 and cool the room temperature and high pressure working gas by performing an enthalpy expansion.

  The helium gas flowing through the room temperature gas supply pipe 42 is cooled by the cooling stage 56 in the first heat exchange unit 95 to become a low temperature gas. The low temperature gas is transferred from the vacuum chamber 20 to the constant temperature bath 36 through the low temperature gas supply pipe 62 connected to the first heat exchange unit 95. The vacuum chamber 20 and the thermostat 36 are connected by a vacuum heat insulation pipe 60, and the low temperature gas supply pipe 62 is inserted into the vacuum chamber 20 to prevent the low temperature gas supply pipe 62 from being heated by the ambient temperature. In the present embodiment, as will be described later, it is also possible to adopt a mode in which the inside of the constant temperature bath 36 is evacuated without blowing low temperature gas and desorption gas inside the constant temperature bath 36. In this case, the vacuum chamber 20 and the thermostatic chamber 36 are communicated by the vacuum heat insulating pipe 60, and the vacuum chamber 20, the vacuum heat insulating pipe 60, and the thermostatic bath 36 are all evacuated by one vacuum pump (not shown). Can do.

  The thermostat 36 accommodates at least a part of the gas component collection pipe 32 into which the sample gas is introduced. Inside the thermostatic chamber 36, a second heat exchange unit 96 is provided for cooling the sample gas with a low-temperature gas and adsorbing the gas component to liquefaction aggregation or adsorbent. In the present embodiment shown in FIG. 3, a low temperature gas supply pipe 62 is wound around the trap portion 34 of the gas component collection pipe 32. However, heat exchange may be performed between the low temperature gas supply pipe 62 and the gas component collection pipe 32 using a heat exchanger. In addition, by passing the low temperature gas from the downstream side to the upstream side of the gas component collection pipe 32 with respect to the second heat exchange part 96 in which the low temperature gas supply pipe 62 is wound around the trap part 34, the trap part 34 is The downstream side is cooled to a lower temperature and the upstream side is cooled more slowly. Thereby, when collecting by liquefying and aggregating, the target gas component introduced from the upstream side of the trap part 34 is gradually liquefied and its vapor pressure falls as it passes through the trap part 34. This can be liquefied and agglomerated without omission on the downstream side of 34. Further, when the target gas component is adsorbed on the adsorbent, the temperature gradient between the sample gas and the cooling gas is minimized on the downstream side of the trap portion 34, so that the temperature of the sample gas can be accurately controlled by a desired value. High adsorbability of the target gas component can be obtained in the portion.

  Moreover, since the cooling device 10 according to the present invention employs a method in which the cold gas is generated by exchanging the normal temperature gas with a refrigerator, the temperature of the low temperature gas can be adjusted accurately and without energy loss. For this reason, for example, in the gas chromatograph device 15 including the cooling device 10 according to the present embodiment, the temperature of the low-temperature gas flowing through the second heat exchange unit 96 is the boiling point temperature of the target gas component or slightly lower than this. By gradually increasing the temperature, only the target gas component that has been liquefied and aggregated can be vaporized and delivered to the separation column. Such temperature adjustment of the low temperature gas can be realized by controlling the output of the regenerative refrigerator 50 and adjusting the temperature of the cooling stage 56.

  Specifically, for example, when the boiling point temperature of the target gas component is −100 ° C., the boiling point temperature of the sample gas is adjusted by adjusting the temperature of the low temperature gas so that the inside of the trap part 34 becomes −100 ° C. All gas components (including the target gas component) having a temperature of −100 ° C. or higher are liquefied and aggregated, and collected in the trap unit 34 as a liquid phase mixed gas. When the mixed gas component is sufficiently collected, the temperature of the low temperature gas is slightly increased so that the temperature inside the trap portion 34 becomes, for example, −99 ° C., and thus −100 of the collected mixed gas components. Only the gas component having a boiling point temperature of from 0 ° C. to −99 ° C. is desorbed to be sent to the separation column as a high-concentration sample gas.

  At this time, the sample gas containing the target gas component and other gas components is mixed with the gas sent to the separation column as a carrier gas. However, since the target gas component is highly concentrated, the separation column is extremely accurate. The target gas component can be separated well. For this reason, the sensitivity of the analyzer in the gas chromatograph device 15 and the separation accuracy and analysis accuracy of the target gas component are improved. Further, by taking the difference between the above component analysis result of the sample gas containing the high concentration sample gas and the component analysis result of the sample gas when the low temperature trap is not performed, the boiling point is −100 ° C. to −99 ° C. Analysis results of only gas components can be extracted.

  In addition, by further reducing the temperature rise width of the low-temperature gas, the temperature inside the trap portion 34 can be made closer to −100 ° C. than −99 ° C., and the target gas component and boiling point temperature are extremely high. Even when other gas components in the vicinity are mixed with the sample gas, only the target gas component can be vaporized using the difference in boiling point temperature between the two.

  Further, for example, when the sample gas is cooled to −101 ° C. in the trap section 34 and the target gas component is liquefied and aggregated and collected, and heated to −99 ° C. for desorption, the temperature is −100 ° C. to −99 ° C. In addition to the gas component having a boiling point (including the target gas component), other gas components having a boiling point of −101 ° C. to −100 ° C. are also collected. In this case, the target gas is further collected by the separation column. Since the separation from the components is performed, the sensitivity and analysis accuracy of the analyzer can be improved. Therefore, according to the gas chromatography method or gas chromatograph apparatus of the present invention, the sample gas is collected by cooling the sample gas to the boiling point temperature of the target gas component or a temperature below this, and is vaporized by heating. Thus, the accuracy of component analysis of the target gas component can be improved.

  As a method of adjusting the temperature inside the trap part 34, the flow rate of the normal temperature helium gas passing through the flow rate adjustment valve 44 in addition to controlling the temperature of the low temperature gas flowing through the second heat exchange part 96 as described above, A method of adjusting the output of the heater 72 that heats the cooling stage 56, the heat exchange unit 22, and the like inside the vacuum chamber 20 with the temperature controller 70 can also be adopted.

  A reflux pipe 94 is connected downstream of the second heat exchange section 96, and the low-temperature gas that has cooled the gas component collection pipe 32 passes through the low-pressure side branch section 93 to the low-pressure gas pipe (exhaust pipe) 54 of the regenerative refrigerator 50. And is sent to the compressor 51 as the working gas of the regenerative refrigerator 50.

  In the cooling device 10 according to the present embodiment, as long as the low-temperature gas used for cooling the gas component collecting pipe 32 can be returned to the low-pressure gas pipe 54 of the regenerator refrigeration machine 50, the second heat The specific configuration of the exchange unit 96 is not particularly limited. As shown in FIG. 3, in addition to a system in which heat is exchanged between the low temperature gas supply pipe 62 and the trap portion 34 of the gas component collection pipe 32, for example, a low temperature gas outlet is provided at the tip of the low temperature gas supply pipe 62. The low-temperature gas is blown out toward the trap portion 34 of the gas component collecting pipe 32 inside the thermostatic chamber 36, the blown-out low-temperature gas is collected by the reflux pipe 94, and the low-pressure gas pipe of the regenerative refrigerator 50 It can also be transferred to the path 54.

  As described above, in the cooling device 10 according to the present embodiment, the entire amount of the low-temperature gas used for cooling the sample cooling unit (gas component collecting pipe 32) is the working gas of the regenerator chiller 50. Is returned to the low pressure gas line 54. For this reason, the apparatus does not consume helium gas at all, and it is not necessary to replenish the room temperature gas or the low temperature gas using a gas container or a gas generator, so that the running cost can be reduced and continuous operation is possible. Become.

It is also preferable to draw the reflux pipe 94 into the vacuum chamber 20 through the vacuum heat insulating pipe 60 and exchange heat with the room temperature gas supply pipe 42 inside the vacuum chamber 20. As described above, after cooling the sample cooling section, the sample is cooled from the compressor 51 at the low temperature remaining in the sample cooling gas (low-temperature gas) that is refluxed from the reflux pipe 94 to the low-pressure gas line 54. By cooling the sample cooling gas at room temperature before being cooled in advance, the cooling load due to the cooling stage 56 of the regenerator refrigerator 50 can be reduced.
Note that the sample cooling gas (normal temperature gas, low temperature gas) is a high pressure gas pipe 52, a normal temperature gas supply pipe 42, a first heat exchange section 95, a low temperature gas supply pipe 62, a second heat exchange section 96, a reflux pipe 94, a low pressure. In the cooling device 10 according to the present embodiment that circulates in the closed cycle including the gas pipeline 54 and the like, the sample cooling gas before being cooled by the cooling stage 56 (low temperature part) is sent from the compressor 51. The sample cooling gas up to the first heat exchange unit 95 is meant, and the sample cooling gas after cooling the sample cooling unit (gas component collecting pipe 32) is cooled by the first heat exchange unit 95. The sample cooling gas up to the compressor 51 is meant.
At this time, as shown in FIG. 3, the low temperature gas heat exchanged with the gas component collecting pipe 32 is heat exchanged with the normal temperature gas flowing through the normal temperature gas supply pipe 42 before it is in thermal contact with the atmosphere. Can be efficiently pre-cooled to reduce the load on the regenerator refrigerator 50.
In addition, in FIG. 3, the third heat exchanging unit 97 using the heat exchanger exemplifies an aspect in which such heat exchange is performed. In addition, the reflux pipe 94 and the room temperature gas supply pipe 42 are wound around each other, You may make both contact with a large contact area.

It is a front view of the cooling device 10 concerning 1st embodiment of this invention. It is a systematic diagram of the cooling device 10 and the gas chromatograph device 15 concerning 2nd embodiment of this invention. It is a systematic diagram of the cooling device 10 and the gas chromatograph device 15 concerning 3rd embodiment of this invention. It is a systematic diagram of the conventional cooling device 100 and the gas chromatograph device 150.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cooling apparatus 15 Gas chromatograph apparatus 20 Vacuum chamber 22 Heat exchange part 24 Cover 28 Gas supply pipe 30 Low temperature trap apparatus 32 Sample cooling part (gas component collection pipe)
40 Nitrogen gas generator 42 Gas introduction pipe (normal temperature gas supply pipe)
50 Regenerative refrigerator 51 Compressor 52 Air supply pipe (high-pressure gas pipeline)
53 Piston 54 Exhaust pipe (low pressure gas line)
55 Cylinder 56 Cooling stage (low temperature part)
57 Switching section 58 Expansion chamber 59 Cold storage material 60 Vacuum insulation pipe 62 Low temperature gas supply pipe (gas outlet pipe)
DESCRIPTION OF SYMBOLS 70 Temperature controller 72 Heater 80 Desorption gas supply pipe 82 Gas exhaust pipe 84 Heat exchange part 86 Gas exhaust port 91 High pressure side branch part 93 Low pressure side branch part 94 Reflux pipe

Claims (6)

A cooling device for an analyzer having a sample cooling unit,
A cylinder,
A piston which is provided inside the cylinder so as to be capable of reciprocating and forms an expansion chamber;
A compressor for compressing the working gas;
An air supply pipe for supplying the compressed working gas to the expansion chamber;
An exhaust pipe that discharges the working gas adiabatically expanded by the reciprocating motion of the piston, and
A low temperature part cooled by the adiabatic expanded low temperature working gas;
A gas supply pipe for supplying the sample cooling gas to the sample cooling unit after cooling the sample cooling gas by heat exchange with the low temperature unit;
A cooling device for an analytical apparatus. The supply pipe is provided with a branched introduction pipe for extracting a part of the working gas supplied to the expansion chamber and introducing it into the gas supply pipe as the sample cooling gas, and
2. The cooling apparatus for an analyzer according to claim 1, wherein the exhaust pipe is provided with a reflux pipe for refluxing the sample cooling gas supplied to the sample cooling section as a working gas.   The cooling device for an analyzer according to claim 1 or 2, further comprising heat exchange means for exchanging heat between the sample cooling gas after cooling the sample cooling portion and the sample cooling gas before being cooled at the low temperature portion.   The sample gas introduced into the sample cooling unit is cooled with the sample cooling gas supplied from the cooling device for an analyzer according to any one of claims 1 to 3, and gas components contained in the sample gas are collected. The gas chromatograph apparatus characterized by performing. In a gas chromatography method for cooling a sample gas and collecting a gas component contained in the sample gas,
A gas chromatography method, wherein a normal temperature gas is heat-exchanged with a low temperature part of a refrigerator to generate a low temperature sample cooling gas, and the sample gas is cooled by the sample cooling gas.   6. The gas according to claim 5, wherein a part of the working gas is extracted from the refrigerator to obtain the room temperature gas, and the sample cooling gas obtained by cooling the sample gas is returned to the refrigerator to obtain the working gas. Chromatographic method.

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