JPH04259857A - Gas chromatograph - Google Patents

Abstract

PURPOSE:To prevent the temperature decrease of a sample gas due to a sample piping, to achieve miniaturization and easy maintenance of the apparatus, and to reduce thermal influences of a heater and a thermostatic chamber to electric components. CONSTITUTION:A manifold 72 of an analyzer apparatus 3 is tightly connected to a housing block of a sample conditioner apparatus 2. A sample gas or standard gas discharging port is directly connected with a sample gas or standard gas introducing port 92. A detector 80 and a heater 90 are incorporated into a sample valve 73, and a first and a second columns 87, 88 are wound in the outer periphery of the valve 73, thereby constituting a unit of the valve. An analyzer board 75, a pressure reducing valve 76, a transformer, etc., are arranged at the bottom in an analyzer case 70. A printed board 101, connectors 106, 107 and the like are accommodated in an electric housing 100, which are separated from a thermostatic chamber 74.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas chromatograph that performs gas analysis by utilizing the difference in adsorption between a packing material packed as a stationary phase in a column and a gas to be measured.

0002

[Prior Art] This type of process gas chromatograph, which analyzes the components of process gas in petrochemical processes, steel processes, etc., uses a sample conditioner to analyze the sample gas separated from the process line under the optimal conditions. This sample gas is supplied to an analyzer device to separate and detect each gas component, and based on the measurement results, process steps are monitored and various controls are performed. FIG. 9 shows a conventional example of such a gas chromatograph, in which 1A and 1B are process lines, 2 is a sample conditioner device, and 3 is an analyzer device, which constitute the gas chromatograph. The sample conditioner device 2 includes a vaporizer (not shown) that completely vaporizes heavy components in the sample gas SG and prevents their condensation, a filter (not shown) that removes dust from the sample gas SG, and a sample gas A rotameter (not shown) that measures the flow rate of SG and standard gas HG, a needle valve (not shown) that adjusts the flow rate of standard gas HG and sample gas SG, a changeover switch (not shown) that switches the flow path, etc. These are built into the housing 4 and connected through piping. On the other hand, the analyzer device 3 has first and second columns 5 connected in series.
, 6, sample valve 7, backflush valve 8,
It is equipped with a detector 9, a pressure reducing valve (not shown), an electrical equipment section 10, a constant temperature bath 11, a heater 12, and the like. The thermostatic chamber 11 houses the first and second columns 5 and 6, a sample valve 7, a backflush valve 8, a detector 9, etc., and a heater 1.
By circulating the air heated by 2, the inside is maintained at the optimum temperature for separation and analysis of the sample gas SG. 1st
The column 5 has an inner diameter of 1 mm to 4 mm and a length of 0.5 to 3 m.
The second column 6 has an inner diameter of 0.1 mm to 4 mm, and can efficiently separate low-boiling components containing less carbon (C) at high speed.
It consists of a capillary column with a length of about 0.5 to 3 m and a liquid phase coated on the inner wall, and it is difficult to separate low-boiling components with low C content, but it is difficult to separate high-boiling components with high C content. It has the characteristics of being able to perform high-speed and efficient separation. During analysis, heavy components with a high amount of C (high boiling point components) in the sample gas SG are discharged through the backflush valve 8 and are not measured in order to shorten the analysis cycle and protect against column deterioration. Only the first column 5
When measuring a C-rich range, the second column 6 separates C-poor gas components (light components) within that range. And the first and second columns 5 and 6
Each gas component separated by is converted into an electrical signal by the detector 9, and this electrical signal is proportional to the concentration of each gas component.

0003

[Problems to be Solved by the Invention] However, in the conventional gas chromatograph having such a configuration, the number of outlets for the sample gas SG and carrier gas CG, the arrangement of the component parts, etc. There was a problem in that the internal temperature distribution could not be made completely uniform, and temperature fluctuations also occurred. For this reason, components such as the columns 5 and 6 cannot be maintained at optimal temperature conditions, and the component concentrations do not match the original sample concentrations, making accurate measurement difficult. For example, in the case of sample gas SG that is easily liquefied, it is desirable to maintain the sample valve 7 and backflush valve 8 at a high temperature, and it is desirable that the temperature of the second column 6 does not fluctuate in order to improve separation performance. . In addition, in the conventional device described above, the sample introduction section between the sample conditioner device 2 and the analyzer device 3 was connected by the sample pipe 13, so the sample pipe 13 was constructed with a double pipe structure in order to prevent the temperature from decreasing in this part. It was necessary to heat and keep warm using steam, etc. Therefore, if the piping structure is complicated and the number of parts increases, and if the sample conditioner device 2 and analyzer device 3 are close, piping work becomes difficult, and if they are too far apart, the temperature will drop significantly, causing heating and heat retention. There was a problem in that a large amount of heat was required. Furthermore, since the electrical equipment section 10 consisting of an amplifier and a temperature control device is arranged together with the heater 12 at the upper part of the thermostatic oven 11, the thermostatic oven 11
The thermal influence caused by the heater 12 is large, and the reliability of the device is reduced. Inside the constant temperature chamber 11, a sample valve 7,
Since the columns 5, 6, the detector 9, etc. are connected and arranged by piping, joints, etc., there are many problems such as difficulty in maintaining them.

[0004] Therefore, the present invention has been made in view of the above-mentioned conventional problems, and its purpose is to reliably heat and keep a sample gas warm, and also to miniaturize the device. It is an object of the present invention to provide a gas chromatograph which is easy to maintain and which can reduce the thermal influence of a heater and a constant temperature bath on electrical parts of an amplifier and a temperature control device.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides an analyzer unit comprising a sample valve incorporating a detector and a heater, and first and second columns wound around the sample valve. An analyzer case consisting of an elliptical spherical body with an internal constant temperature chamber set up in the center and an analyzer board, pressure reducing valve, transformer, etc. arranged around it below.
The analyzer case includes a cylindrical electric housing having a printed circuit board, a connector, etc., and protruding from the outer periphery of the analyzer case, and a carrier gas inlet, a sample gas or standard gas inlet, and a sample gas outlet. The housing block includes a manifold fitted into a bottom opening, and a housing block closely fixed to the lower surface of the manifold, and the housing block includes a sample gas supply port, a standard gas supply port, a carrier gas supply port, a bypass vent port, A sample vent port, a steam inlet, a steam outlet, and a carrier gas outlet, a sample gas or standard gas outlet, and a sample gas that communicate with the carrier gas inlet, sample gas or standard gas inlet, and sample gas outlet of the manifold, respectively. It is constructed by forming an inlet and a communication path that communicates these ports, and disposing a filter, a rotameter, a needle valve, and a changeover switch in the middle of the communication path.

[0006]

[Operation] In the present invention, the detector, the sample valve with a built-in heater, and the first and second columns wrapped around the valve form an analyzer unit, which facilitates the assembly work. By protruding from the analyzer case, the electric housing separates the constant temperature chamber from the printed circuit board, connectors, etc. The manifold and the housing block are brought into close contact with each other, and the carrier gas inlet, sample gas or standard gas inlet, and sample gas outlet are in communication with the carrier gas outlet, sample gas or standard gas outlet, and sample gas inlet, respectively. This eliminates the need for sample piping. The analyzer board, transformer, etc. are located inside the analyzer case at the bottom, so there is little thermal influence from the constant temperature oven.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below based on embodiments shown in the drawings. FIG. 1 is a sectional view showing an embodiment of the gas chromatograph according to the present invention, and FIG. 2 is an external perspective view showing the gas chromatograph attached to a stanchion.
3 is a perspective view showing the internal structure of the sample conditioner device, FIG. 4 is an external perspective view of the housing block, FIG. 5 is a sectional view taken along the line V-V in FIG. 4, and FIG. 6 is a sectional view taken along the line VI-VI in FIG. 4. , FIG. 7 is a bottom view of the manifold, and FIG. 8 is VII of FIG.
It is a sectional view taken along the line I-VIII.

In FIGS. 1 and 2, the entire reference numeral 20
The gas chromatograph shown by is composed of a sample conditioner device 2, an analyzer device 3 installed on the sample conditioner device 2, and an electrical equipment section 21 connected and fixed to the front of the analyzer device 3. It is fixed via a bracket 24 with a plurality of bolts 23.

The structure of the sample conditioner device 2 will be described in detail with reference to FIGS. A housing block 31 made of metal such as stainless steel is housed.

The housing block 31 has substantially horizontal upper and lower blocks 31A and 31B that face each other vertically.
and a substantially vertical connecting portion 31C that connects both blocks 31A and 31B.The top surface of the upper block 31A includes a carrier gas outlet 32, a sample gas or standard gas outlet 33, and a sample gas inlet 34. A small block 36 having a plurality of screw holes 35 is connected to the setscrew 2.
7 and covered by a cover 25 (see FIG. 1). Further, two needle valve adjustment holes 37a and 37b are opened on the front surface of the upper block 31A, a carrier gas supply port 38 is opened on the left side, and a bypass vent port 39 and a sample vent port 40 are opened on the right side. There is. Inside the housing block 31, the carrier gas outlet 32 and the carrier gas supply port 38 are provided.
a carrier gas flow path 41 that communicates with the sample gas or standard gas outlet 33, a sample gas or standard gas flow path 44 that connects the sample gas supply port 42 or the standard gas supply port 43, and the bypass vent port 39. a bypass vent flow path 45 that connects the sample gas or standard gas flow path 44; a sample vent flow path 46 that connects the sample gas inlet 34 and the sample vent port 40;
A standard gas flow path 48 and a steam flow path 49 connecting the standard gas supply port 43 and the changeover switch 47 are formed. In addition, in FIG. 4, 28 is a manifold 7, which will be described later.
A bolt mounting hole 29 through which a bolt 65 for fixing the manifold 2 is inserted from below is a positioning pin for positioning the manifold 72.

[0011] The sample gas or standard gas flow path 4
Needle valves 50 and 51 are disposed in the middle of the bypass vent flow path 4 and the bypass vent flow path 45, respectively. Needle valve 50, 5
1 are inserted into the needle valve adjustment holes 37a and 37b, respectively, and are configured to be adjusted from the outside. A carrier gas CG is supplied to the carrier gas supply port 38.
is fed into the analyzer device 3 through the carrier gas channel 41. A measured sample gas SG separated and analyzed by the analyzer device 3 is introduced into the sample gas inlet 34, passes through a sample vent channel 46, and is discarded from the sample vent port 40.

Two filter mounting holes 54a and 54b for accommodating filters 52 and 53, respectively, and a vaporizer mounting hole 56 for accommodating a vaporizer 55 are provided on the front surface of the lower block 31B, and the lower surface is provided with the sample gas A supply port 42, a standard gas supply port 43, a steam inlet 57, and a steam outlet 58 are provided, and in addition to the filters 52, 53 and vaporizer 55, a changeover switch 47 is incorporated inside. The needle valve 5 is provided in the middle of the sample gas or standard gas flow path 44.
0, filters 52 and 53, a vaporizer 55, a changeover switch 47, and a second rotameter 60 are incorporated. In addition to the needle valve 51, a first rotameter 59 is incorporated in the bypass vent flow path 45. The vaporizer 55 is provided in the flow path between the sample gas supply port 42 and the filter 52. Standard gas HG is introduced to the standard gas supply port 43.

[0013] The first and second rotameters 59 and 60
are each composed of a tapered tube and a float, the first rotameter 59 measures the bypass flow rate of the sample gas SG, and the second rotameter 60 measures the analyzer input flow rate. The upper and lower ends are removably held in the holder. Further, a thermometer 6 for measuring the temperature of the housing block 31 is provided between the upper block 31A and the lower block 31B.
2 (FIG. 4) is located between both rotameters 59 and 60. Note that the first rotameter 59 is provided between the filter 52 and the needle valve 51, and the second rotameter 60 is interposed between the filter 53 and the needle valve 50.

The changeover switch 47 is connected to the lower block 3.
It is switched by turning the switching knob 63 provided on the right side of 1B by a driving means such as a motor (or manual operation) driven by a signal from the control unit. The flow path 44 is connected to the standard gas flow path 48, and the flow path 64 between the sample gas supply port 42 and the changeover switch 47 is closed. Therefore, during calibration using the standard gas, the sample gas SG led from the sample gas supply port 42 is distributed between the vaporizer 55 - the first rotameter 59 - the needle valve 51 - the bypass vent channel 45
The standard gas HG that is disposed of through the bypass vent port 39 and supplied from the standard gas supply port 43 is guided to the analyzer device 3 via the changeover switch 47 - filter 53 - second rotameter 60 - needle valve 50. . At this time, the flow path 64 is closed by the changeover switch 47.

On the other hand, during measurement (when sample gas is supplied), sample gas SG is supplied to the analyzer via vaporizer 55 - filter 52 - changeover switch 47 - filter 53 - second rotameter 60 - needle valve 50 instead of standard gas HG. When the sample gas SG is guided to the device 3 and the sample gas SG is separated, the changeover switch 47 is switched back to the standard gas HG.
The calibration state is switched to the calibration state according to the calibration method, and the supply of the standard gas HG is restarted.

Note that the vaporizer 55, filter 52,
53, rotameters 59, 60, and changeover switch 47 are conventionally known, so detailed explanations of their configurations and the like will be omitted.

A portion of the steam flow path 49 is formed inside the connecting portion 31C that connects the upper and lower blocks 31A and 31B, and by supplying steam ST thereto, the housing block 31 performs heat exchange. The sample gas SG is heated to a predetermined temperature (120°C to 150°C).
It is heated and kept at a temperature of around 30°F (°C). Steam S
The temperature of T is about 150°C, the pressure is 10Kgf/cm2
It is as follows.

Next, details of the analyzer device 3 will be explained in detail based on FIGS. 1 and 7. The analyzer device 3 includes an aluminum die-cast analyzer case 70 made of an elliptical spherical body that is installed and fixed on the small block 36 of the sample conditioner device 2 with its long axis directed in the front-rear direction.
The small block 36 of the housing block 31 is provided in the lower opening 71 of the analyzer case 70.
A manifold 72 is positioned above the small block 36 by the pins 29 (FIG. 4) and fixed by bolts 65 from the lower side of the small block 36. A sample valve 73 and a thermostat 74 surrounding it are arranged on the top surface of the manifold 72, and an analyzer board 75 equipped with electrical components is arranged around the thermostat at the bottom of the case.
, a pressure reducing valve 7 that reduces the pressure of the carrier gas CG to a predetermined pressure.
6, a transformer 77, etc. are provided.

The sample valve 73 switches the fluid passage 78 formed inside, and controls the sample gas SG during measurement.
to the detector 80, and the carrier gas CG to the detector 80 during non-measurement and backflushing.For example, by using a well-known pneumatically driven diaphragm valve, the center plate 81 and the center plate 81 diaphragms 82 and 83 on the front and back surfaces of the
A plurality of plungers 84 are arranged vertically to face each other.
The upper and lower pistons 85 and 86 actuate the upper and lower plungers 84 alternately, and the diaphragms 82 and 8
3 are alternately elastically deformed, and the upper and lower plungers 84 are operated by the pistons 85 and 86 to form the diaphragm 82,
By alternately pressing against 83, the upper route and lower route of the fluid passage 78 are alternately switched. Around the sample valve 73, there are first and second columns 87 for separating the sample gas SG into each gas component.
88 are wound with the second column 88 inside. The first column 87 is the aforementioned packed column, and the second column 88 is a capillary column. The sample valve 73 includes the detector 80 and the first
, a heater 90 that heats the second columns 87, 88 to a predetermined temperature is incorporated, and these and the columns 87, 88 are heated to a predetermined temperature.
8 forms an analyzer unit. The sample valve 73 itself is constructed in the same manner as a conventionally known pneumatically driven diaphragm valve, except that a detector 80 and a heater 90 are incorporated into the valve, so no further explanation will be given. Omitted.

As shown in FIG. 7, the lower surface of the manifold 72 has a carrier gas inlet 91, a sample gas or standard gas inlet 92, and a sample gas outlet 93.
A carrier gas outlet 32 and a sample gas or standard gas outlet 3 open on the top surface of the small block 36 (FIG. 4).
3. The carrier gas inlet 91, the sample gas or standard gas inlet 92, and the sample gas outlet 93 are formed in the manifold so as to be respectively connected to the sample gas inlet 34. It communicates with the fluid passage 78 of the sample valve 73 via a flow path 95 (FIG. 1). A lid 97 is screwed into the top opening 96 of the analyzer case 70, forming an explosion-proof case together with an electric housing 100, which will be described later. Further, in FIG. 7, 98 is a screw hole into which the bolt 65 is screwed, and 99 is a sample conditioner device 3.
This is the screw hole for assembling the bracket when there is no one.

In FIGS. 1 and 8, the electric equipment section 21 includes the electric housing 100 projecting from the front surface of the analyzer case 70. As shown in FIGS. The electric housing 100 is formed into a cylindrical shape by die-casting aluminum, and includes a printed circuit board 101 for driving and controlling the gas chromatograph 20, such as a thermostat temperature control circuit, etc.
Board fixing bracket 10 that holds printed circuit board 101
2, 103, a decorative board 104, a grounding fitting 105, connectors 106, 107, etc. are housed. The case side connector 107 and the analyzer device 3 are electrically connected by a cord 108. Also, electric housing 100
On the upper and lower parts of the inner circumferential surface of each of the board fixing brackets 102, there are long detent/guide grooves 110 and 111 in the axial direction.
, 103. At the rear end of each of the board fixing brackets 102 and 103 are protrusions 112 and 113 that are inserted into the respective detent and guide grooves 110 and 111.
are protruding from each. In addition, 121 is the lid body 12
A glass 123 closes the opening 122 of 0, and a name plate.

In the electrical equipment section 21 having such a configuration, the electrical housing 100 of the printed circuit board 101
When installing the printed circuit board 101 into the electric housing 100, the protrusions 112 and 113 are inserted into the locking/guide grooves 110 and 111, and the printed circuit board 101 is inserted into the electric housing 100 together with the circuit board fixing brackets 102 and 103. Then, the board-side connector 106 and the case-side connector 107 are matched and connected, and when the connection is complete, the protrusions 112, 1
13 comes into contact with the inner wall of the rotation stopper/guide grooves 110 and 111, and further insertion is prevented. Next, the lid body 120
By screwing into the front opening of the electric housing 100, the installation work of the printed circuit board 101 and the lid 120 is completed. In this screwing operation of the lid body 120, the printed circuit board 101 is
A rotational moment acts on the board fixing brackets 102 and 103, but the anti-rotation and guide grooves 110 and 111
and the brackets 102 and 10 by the protrusions 112 and 113.
3 is prevented from rotating, the printed circuit board 101, brackets 102, 103, connectors 106, 107, etc. are not twisted or damaged.

According to the gas chromatograph 20 having such a configuration, the carrier gas inlet 9 is provided in the manifold 72 that closes the lower end opening 71 of the analyzer case.
1. A sample gas or standard gas inlet 92 and a sample gas outlet 93 are provided, and these are opened on the top surface of the small block 36 (FIG. 4) of the sample conditioner device 2. Since they are directly connected to the outlet port 33 and the sample gas inlet port 34, it is possible to prevent the temperature of the sample gas SG from decreasing, and since no sample piping is required, the structure is simple and parts such as fittings can be easily assembled. Work man-hours can be reduced. In addition, a detector 80 and a heater 90 are incorporated into the sample valve 73, the valve 73 and the detector 80 are connected by a fluid passage 78 formed inside the valve, and first and second columns 87 and 88 are wound around the outer circumference of the valve. Since this unit is placed inside the thermostatic oven 74, there is no need to connect the valve 73 and the detector 80 with piping. Once opened, the analyzer unit can be easily taken out, making maintenance easy. Furthermore, electrical components such as a printed circuit board 101 such as a constant temperature oven temperature control circuit, connectors 106 and 107, etc. are attached to the analyzer case 70.
Since it is housed in an electric housing 100 protruding from the front surface of the electric housing 100 and is far away from the constant temperature bath 74, the thermal influence of the constant temperature bath 74 is small, improving the reliability of the device. Further, the analyzer case 70 is formed into an elliptical spherical shape and has a large surface area, and effectively radiates the heat generated by the constant temperature bath 74. Further, since the analyzer board 75, the pressure reducing valve 76, the transformer 77, etc. are arranged at the inner bottom of the analyzer case 70, the thermal influence of the thermostatic chamber 74 can be reduced.

[0024]

Effects of the Invention As explained above, according to the gas chromatograph according to the present invention, the fluid passage ports of the analyzer device and the sample conditioner device are directly connected, eliminating the need for sample piping, which reduces the temperature of the sample gas. In addition, the assembly work is simple and the number of parts such as joints can be reduced. In addition, the present invention incorporates a detector and a heater inside the sample valve, and wraps two columns around the outer periphery to form a unit. This eliminates the need for piping between the valve and the detector, making maintenance easier. do. In addition, the amplifier, temperature control device printed circuit board, connectors, etc. are housed inside the electric housing and are separated from the thermostatic oven, so there is less thermal influence from the thermostatic oven, improving the reliability of the equipment. , the effect is great.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of a gas chromatograph according to the present invention.

FIG. 2 is an external perspective view showing the gas chromatograph attached to a stanchion.

FIG. 3 is a perspective view showing the internal structure of the sample conditioner device.

FIG. 4 is an external perspective view of the housing block.

FIG. 5 is a sectional view taken along the line V-V in FIG. 4;

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 4;

FIG. 7 is a bottom view of the manifold.

FIG. 8 is a sectional view taken along line VIII-VIII in FIG. 1;

FIG. 9 is a front view showing a conventional example of a gas chromatograph.

[Explanation of symbols]

2 Sample conditioner device 3 Analyzer device 20 Gas chromatograph 31 Housing block 32 Sample gas outlet 33 Sample gas or standard gas outlet 34 Sample gas inlet 38 Carrier gas supply port 39 Bypass vent port 40 Sample vent port 42 Sample gas supply port 43 Standard gas supply port 47 Changeover switch 50, 51 Needle valve 52, 53 Filter 57 Steam inlet 58 Steam outlet 59, 60 Rotameter 70 Analyzer case 72 Manifold 73 Sample valve 74 Constant temperature chamber 75 Analyzer board 76 Pressure reducing valve 77 Transformer 80 Detection Container 87 First column 88 Second column 90 Heater 91 Carrier gas inlet 92 Sample gas or standard gas inlet 93 Sample gas outlet 100 Electric housing 101 Printed circuit board 106 107 Connector

Claims (1)

[Claims] [Claim 1] A thermostat containing a sample valve with a built-in detector and a heater, and an analyzer unit with first and second columns wrapped around it is erected in the center; An analyzer case consisting of an elliptical spherical body with an analyzer board, a pressure reducing valve, a transformer, etc. arranged below, and a cylindrical electric housing having a printed circuit board, connectors, etc. and protruding from the outer periphery of the analyzer case. , a manifold having a carrier gas inlet, a sample gas or standard gas inlet, and a sample gas outlet and fitted into the bottom opening of the analyzer case, and a housing block closely fixed to the lower surface of the manifold. The housing block has a sample gas supply port, a standard gas supply port, a carrier gas supply port, a bypass vent port, a sample vent port, a steam inlet, a steam outlet, and a carrier gas inlet of the manifold, a sample gas a carrier gas outlet that communicates with the standard gas inlet and sample gas outlet, respectively;
A communication path is formed that communicates the sample gas or standard gas outlet and the sample gas inlet, and a filter, a rotameter, a needle valve, and a changeover switch are provided in the middle of the communication path. A gas chromatograph featuring: