Total Organic Carbon Dioxide Analyzer and Combustion Reaction Unit

Abstract

In order to enable a vaporizing member and a catalyst to be disposed close to one another in a configuration in which a sample vaporized by the vaporizing member is caused to pass through the catalyst, a total organic carbon meter 100 for measuring the total organic carbon contained in a liquid sample includes a combustion reaction portion 32 for burning the total organic carbon contained in the liquid sample to generate carbon dioxide, and a carbon dioxide detecting portion X for detecting the carbon dioxide generated by the combustion reaction portion 32, wherein the combustion reaction portion 32 includes a combustion furnace main body 33, a vaporizing member 34 accommodated inside the combustion furnace main body 33, a heating mechanism for heating the vaporizing member 34, and the catalyst, disposed below the vaporizing member.

Description

Technical Field

[0001] The present invention relates to a total organic carbon meter used for analyzing, for example, water quality, and a combustion reaction unit used therefor.

Background Art

[0002] Some total organic carbon meters of this type are configured to guide a liquid sample to a combustion furnace made of ceramics to burn all the organic carbon contained in the liquid sample, and detect the carbon dioxide generated thereby, as shown in Patent Document 1.

[0003] Specifically, the heating furnace of this total organic carbon meter has a double-tube structure consisting of an outer cylinder and an inner cylinder provided inside the outer cylinder. A vaporization member is disposed below the inner cylinder, and a catalyst is provided between the outer cylinder and the inner cylinder. With this configuration, the sample is introduced from the upper part of the inner cylinder and dropped onto the vaporization member. After being vaporized by this vaporization member, it rises toward the space between the inner cylinder and the outer cylinder and passes through the catalyst.

[0004] However, with such a configuration, a space (air layer) for raising the vaporized sample and guiding it to the catalyst is required between the vaporization member and the catalyst, and the vaporization member and the catalyst are arranged separately, so there is concern about a decrease in vaporization efficiency.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Therefore, the present invention has been made to solve the above problems, and its main problem is to enable the vaporization member and the catalyst to be arranged closer to each other in a configuration in which the sample vaporized by the vaporization member is passed through the catalyst. [Means for solving the problem]

[0007] In other words, the total organic carbon meter according to the present invention is a total organic carbon meter for measuring the total organic carbon contained in a liquid sample, and comprises a combustion reaction unit that burns the total organic carbon contained in the liquid sample to generate carbon dioxide, and a carbon dioxide detection unit that detects the carbon dioxide generated by the combustion reaction unit, wherein the combustion reaction unit comprises a combustion furnace body, a vaporization member housed inside the combustion furnace body, a heating mechanism for heating the vaporization member, and a catalyst disposed below the vaporization member.

[0008] In a total organic carbon monoxide analyzer configured in this way, the catalyst is positioned below the vaporizing element. This eliminates the need to raise the vaporized sample towards the catalyst, allowing the vaporizing element and catalyst to be placed closer together. This improves the combustion efficiency of organic matter in the liquid sample, and consequently, improves measurement accuracy.

[0009] In order to more significantly exhibit the effects described above, it is preferable that the catalyst is in contact with the vaporization member inside the combustion furnace body. With this arrangement, the catalyst and vaporizing component can be placed without an air layer in between, making the aforementioned improvements in combustion efficiency more effective.

[0010] A more specific embodiment is one in which the vaporizing member and the catalyst are made of different materials.

[0011] Preferably, the combustion furnace body has an inner furnace body into which the liquid sample is introduced and an outer furnace body surrounding the inner furnace body. With this configuration, the heating furnace body has an inner furnace body into which the liquid sample is introduced and an outer furnace body surrounding the inner furnace body. Therefore, the inner furnace body can suppress cracking and other damage caused by the expansion of the outer furnace body.

[0012] To prevent the cracks and other damage mentioned above, it is preferable to form the outer and inner cylinders from ceramics. However, when attempting to form a heating furnace from ceramic outer and inner cylinders, problems such as poor workability arise. Therefore, the outer furnace body is characterized in that its inner circumferential surface has the same cross-sectional shape as a straight tube from one end opening to the other end opening.

[0013] With this configuration, the outer furnace body has a straight tubular shape with the same cross-sectional shape on its inner circumferential surface from one end opening to the other end opening. This allows the outer furnace body to be easily molded, for example, by drawing, thus improving workability.

[0014] Preferably, the vaporizing member is a granular body made of ceramics, the heating mechanism has a heater surrounding the axial center of the outer furnace body, and a holding member is provided inside the inner furnace body to hold the granular body in the axial center of the combustion furnace body. With this configuration, the ceramic granular material can be held near the heater by the retaining member.

[0015] In order to allow the carbon dioxide vaporized by the granular material to pass through the holding member, it is preferable that the holding member has a passage for passing the gas generated from the liquid sample.

[0016] Preferably, the inner furnace body, the vaporization member, and the holding member are integrated into a single unit and configured to be detachable from the outer furnace body as a whole. This configuration allows for improved maintainability, such as replacement work.

[0017] Preferably, the outer furnace body has a metal introduction flange connected to the end on the one-end opening side, a resin sample introduction tube for introducing the liquid sample into the combustion furnace body is connected to the introduction flange, and a cooling mechanism is provided outside the introduction flange to cool the sample introduction tube by cooling the introduction flange. With this configuration, since a resin sample introduction tube is used, a predetermined amount of liquid sample can be introduced into the combustion furnace body without any residue remaining in the sample introduction tube, and the sample introduction tube can be efficiently cooled by the cooling mechanism.

[0018] As a specific embodiment, the outer furnace body has a metal inlet flange portion detachably connected to the end with one opening, and a metal outlet flange portion detachably connected to the end with the other opening.

[0019] Preferably, a gas return mechanism is provided on the upstream or downstream side of the combustion reaction section to return the gas flowing out of the combustion reaction section back to the combustion reaction section. With this configuration, it is possible to improve the combustion efficiency in the combustion reaction section.

[0020] Preferably, the system is separated into a sampling unit for sampling the liquid sample, a combustion reaction unit having the combustion reaction section, a dehumidification unit having a dehumidification section for dehumidifying the gas flowing out of the combustion reaction section, and a control unit having a control unit for controlling the total organic carbon meter. With this configuration, each function is unitized and separated, which increases the flexibility in arranging each unit.

[0021] As a specific embodiment of the unitization, one of the units may have a support with a roughly U-shaped cross-section, which has a pair of side plates and a front plate connecting the pair of side plates, and the components constituting the unit are supported by the support.

[0022] However, in the total organic carbon meter according to the present invention, various components such as multiple valves and sample weighing units are connected by numerous pipes. For example, when a user assembles each unit, there is a risk that they may mistakenly connect a component to a component other than the one they are supposed to connect. This can lead to malfunctions such as incorrect weighing, and the measurement accuracy cannot be guaranteed. Therefore, it is preferable to further provide a diagnostic function for diagnosing the connection point between the sampling unit and the combustion reaction unit, and the diagnostic function compares the actual pressure, which is the pressure when gas is introduced into the diagnostic area including the connection point, with the reference pressure, which is the pressure when gas is introduced into the diagnostic area during normal operation, to diagnose the connection point. With such a configuration, it is possible to notify the user of connection defects or incorrect connections during assembly.

[0023] The combustion reaction unit according to the present invention is used in a total organic carbon meter for measuring all organic carbon contained in a liquid sample, and is a combustion reaction unit that burns all organic carbon contained in the liquid sample to generate carbon dioxide, and includes a combustion furnace body, a vaporization member housed inside the combustion furnace body, a heating mechanism for heating the vaporization member, and a catalyst disposed below the vaporization member. According to the combustion reaction unit configured as described above, the same operational effects as those of the total organic carbon meter described above can be achieved.

Advantages of the Invention

[0024] According to the present invention configured as described above, in the configuration in which the sample vaporized by the vaporization member is passed through the catalyst, the vaporization member and the catalyst can be arranged close to each other.

Brief Description of the Drawings

[0025] [Figure 1] Schematic diagram showing the configuration of a total organic carbon meter according to an embodiment of the present invention. [Figure 2] Schematic diagram showing the flow path configuration of the embodiment. [Figure 3] Schematic diagram showing the configuration of the sampling unit of the embodiment. [Figure 4] Schematic diagram showing the peripheral structure of the sample introduction tube of the embodiment. [Figure 5] Schematic diagram showing the internal structure of the combustion reaction unit of the embodiment. [Figure 6]A schematic diagram showing the unitized inner furnace body, vaporization member, and holding part of the same embodiment. [Figure 7] A schematic diagram showing the configuration of the dehumidification unit of the same embodiment. [Figure 8] A schematic diagram showing the flow path configuration of another embodiment. [Figure 9] A schematic diagram showing the flow path configuration of another embodiment. [Figure 10] A schematic diagram showing the flow path configuration of another embodiment. [Explanation of Symbols]

[0026] 100... Total Organic Carbon Dioxide 10 ···Main unit of the device 20 ···Sampling Unit 30 ···Combustion reaction unit 40 ···Dehumidifying Unit 50 ···Control Unit 31 ···Sample weighing section 311... Sample introduction tube 312... Blower fan 32 ···Combustion reaction section 33... Combustion furnace body 331...Inner furnace body 332...Outer furnace body 34 ···Vaporizing component 35 ···Retaining member [Modes for carrying out the invention]

[0027] An embodiment of the total organic carbon meter according to the present invention will be described below with reference to the drawings.

[0028] The total organic carbon meter 100 according to this embodiment indicates the total amount of organic matter contained in a liquid sample, such as tap water or sewage, as the amount of carbon contained in the organic matter. Specifically, as shown in Figure 1, it comprises a main body 10, a sampling unit 20, a combustion reaction unit 30, a dehumidification unit 40, and a control unit 50.

[0029] [Device body 10] As shown in Figure 1, the main body of the device 10 is equipped with a housing 11 that accommodates the aforementioned units 20 to 50, and the units 20 to 50 are attached to this housing 11 by fasteners such as screws. These units 20 to 50 are detachable from the housing 11, allowing the user to customize the arrangement of the units 20 to 50 within a certain degree of freedom. Figure 1 shows an example of such an arrangement, where the housing 11 is divided into upper, middle, and lower sections, with the control unit 50 in the upper section, the sampling unit 20 on the right side of the middle section (viewed from the front), the combustion reaction unit 30 on the left side of the middle section (viewed from the front), and the dehumidification unit 40 in the lower section. However, the arrangement of the units is not limited to this.

[0030] In this embodiment, the main body 10 and each of the units 20-50, or the units 20-50 to each other, are connected via, for example, electrical wiring or piping through which liquids or gases flow. More specifically, each of the units 20-50 is configured to be connected to the main body 10 or another unit 20-50 with a single touch via a connector having multiple connection pins, such as a 20-pin connector.

[0031] [Sampling Unit 20] As shown in Figure 2, the sampling unit 20 comprises a sample container 21 in which a liquid sample is stored, a pre-processing unit having a valve 22 for supplying an acid such as hydrochloric acid to the sample container 21, and a carrier gas supply unit 23 for supplying a carrier gas. By making the liquid sample acidic and performing aeration treatment, inorganic carbon contained in the liquid sample is released, and the liquid sample is then sent to the combustion reaction unit 30 by the carrier gas.

[0032] More specifically, as shown in Figure 3, the sampling unit 20 has a support 24 with a roughly U-shaped cross-section, which has a pair of side plates 241 and a front plate 242 connecting the pair of side plates 241. Various components that constitute the sampling unit 20, such as a sample container 21, a pump, an on / off valve, and a filter, are supported on this support 24. In this embodiment, the support 24 is made by bending a single sheet of metal, and replacement parts that are removed during maintenance are attached to the front surface 24a of the front plate 242, while standard components such as piping, electrical wiring, and connectors are attached to the back surface 24b of the front plate 242.

[0033] [Combustion reaction unit 30] As shown in Figure 2, the combustion reaction unit 30 includes a sample measuring unit 31 that measures a predetermined amount of the liquid sample sampled by the sampling unit 20 described above, and a combustion reaction unit 32 into which the measured predetermined amount of liquid sample is injected.

[0034] The sample measuring unit 31 measures a predetermined amount of liquid sample using, for example, a component with a known volume. In this embodiment, as shown in Figure 2, a measuring container capable of measuring a predetermined amount of liquid sample is used, and the predetermined amount of liquid sample can be stored in this measuring container.

[0035] The predetermined amount of liquid sample measured in this manner is injected into the combustion reaction section 32 together with the carrier gas supplied by the carrier gas supply section 23 by switching a three-way valve, which is an on / off valve connected downstream of the sample measuring section 31. Here, a buffer tank T is provided in the carrier gas flow path where the carrier gas is stored, and the carrier gas stored in this buffer tank T is poured in all at once. However, this buffer tank T is not necessarily required.

[0036] As shown in Figure 4, a predetermined amount of liquid sample is introduced into the combustion reaction section 32 from the sample introduction tube 311. However, if a sample introduction tube 311 made of, for example, highly heat-resistant ceramic is used, the liquid sample may adhere to and remain on its inner surface, making it impossible to inject the entire predetermined amount of liquid sample.

[0037] Therefore, in this embodiment, the sample weighing unit 31 is connected to a resin sample introduction tube 311 made of, for example, fluororesin, and a cooling mechanism, a blower fan 312, is provided to cool the sample introduction tube 311 in order to reduce the thermal influence of the combustion reaction unit 32 on the sample introduction tube 311. Furthermore, the sample introduction tube 311 does not necessarily have to be made of resin; for example, a tube made of ceramic or metal with a water-repellent coating on its inner surface may also be used.

[0038] The combustion reaction section 32 receives a predetermined amount of liquid sample from the sample introduction tube 311 and burns all the organic carbon contained in this liquid sample to generate carbon dioxide.

[0039] Specifically, as shown in Figure 5, the combustion reaction unit 32 comprises a combustion furnace body 33, a vaporization member 34 housed inside the combustion furnace body 33, a holding member 35 for holding the vaporization member 34, and a heating mechanism 36 for heating the vaporization member 34.

[0040] The combustion furnace body 33 is cylindrical in shape, into which a liquid sample is introduced through an opening at one end and carbon dioxide is discharged through an opening at the other end. Specifically, it has a double-tube structure consisting of an inner furnace body 331 into which the liquid sample is introduced and an outer furnace body 332 surrounding the inner furnace body 331.

[0041] The inner furnace body 331 is made of, for example, ceramics and is interposed between the outer furnace body 332 and the vaporization member 34 to prevent cracking or other damage caused by the expansion of the outer furnace body 332.

[0042] In this embodiment, the inner furnace body 331 has a straight tubular shape with the same cross-sectional shape on both its inner circumferential surface 331a and outer circumferential surface 331b from one end opening to the other end opening, and is formed, for example, by drawing. However, the inner furnace body 331 may have parts of its inner circumferential surface 331a or outer circumferential surface 331b cut out, and does not necessarily have to be a straight tubular shape.

[0043] The outer furnace body 332 is made of, for example, ceramics and is provided with a gap between it and the outer circumferential surface 331b of the inner furnace body 331, where the central axis of the outer furnace body 332 and the central axis of the inner furnace body 331 are arranged coaxially.

[0044] In this embodiment, the outer furnace body 332 has an inner circumferential surface 332a that is straight and tubular in shape from one end opening to the other end opening, and is formed by, for example, drawing. However, the outer furnace body 332 may have a portion of its inner circumferential surface 332a cut out, and does not necessarily have to be straight and tubular.

[0045] The outer furnace body 332 has a metal inlet flange portion 37 detachably connected to one end with an opening, and a metal outlet flange portion 38 detachably connected to the other end with an opening.

[0046] The introduction-side flange portion 37 is, for example, annular in shape, and in this case has a pair of opposing annular elements 371 and 372 (hereinafter referred to as the first element 371 and the second element 372) and fasteners B1 such as bolts that fasten them together.

[0047] The first element 371 is made of metal and is provided at the upper end of the outer furnace body 332 via a sealing member S1. The resin sample introduction tube 311 described above is fixed to this first element 371. Specifically, a screw hole H1 is formed in this first element 371 that communicates with the internal space of the outer furnace body 332, and the sample introduction tube 311 described above is held by a bolt member B that is screwed into this screw hole H1 (see Figure 4).

[0048] With this configuration, the sample introduction tube 311 is connected to the introduction-side flange portion 37, for example, along the tube axis of the inner furnace body 331, by screwing the bolt member B, to which the sample introduction tube 311 is fixed, into the screw hole H1 of the first element 371.

[0049] The second element 372 is made of metal and has an inner diameter slightly larger than the outer diameter of the outer furnace body 332, and is fixed to the first element 371 using fasteners B1. More specifically, a downward step portion D1 is formed on one of the inner circumferential surface of the second element 372 and the outer circumferential surface 332b of the outer furnace body 332 on the one-end opening side, and an upward step portion D2 is formed on the other, with an upper intermediate member 373 interposed between these downward step portion D1 and upward step portion D2.

[0050] This upper intermediate member 373 is composed of, for example, a pair of halved elements obtained by cutting a ring plate in half, and its inner diameter is equal to the outer diameter of the downward step portion D1 formed on the outer circumferential surface 332b on one end opening side of the outer furnace body 332.

[0051] The following procedure is an example of a connection method for connecting the introduction flange portion 37 to the opening at one end of the outer furnace body 332.

[0052] First, the second element 372 is passed through the opening at one end of the outer furnace body 332, and each of the pair of split elements is fitted onto the downward step portion D1 formed on the outer peripheral surface of the opening at one end of the outer furnace body 332 to form an annular upper intermediate member 373. Next, this upper intermediate member 373 is sandwiched between the downward step portion D1 and the upward step portion D2 of the second element 372, and the second element 372 is fixed to the first element 371 with a fastener B1.

[0053] Outside the introduction-side flange portion 37 configured in this manner, a blower fan 312, which is the cooling mechanism described above, is provided. The blower fan 312 cools the metal first element 371 and the bolt member B that holds the sample introduction tube 311, thereby cooling the sample introduction tube 311.

[0054] The outlet flange portion 38 is, for example, annular in shape, and in this case has a pair of opposing annular elements 381 and 382 (hereinafter referred to as the third element 381 and the fourth element 382) and fasteners B2 such as bolts that fasten them together.

[0055] The third element 381 is made of metal and is provided at the lower end of the outer furnace body 332 via a sealing member S2. A gas outlet pipe (not shown here) is fixed to this third element 381. Specifically, a screw hole H2 is formed in this third element 381 that communicates with the internal space of the outer furnace body 332, and the gas outlet pipe is connected to this screw hole H2, for example, via a fitting.

[0056] The fourth element 382 is made of metal and has an inner diameter slightly larger than the outer diameter of the outer furnace body 332, and is fixed to the third element 381 using fasteners B2. More specifically, a downward step portion D3 is formed on one of the inner circumferential surface of the fourth element 382 and the outer circumferential surface 332b on the other end opening side of the outer furnace body 332, and an upward step portion D4 is formed on the other side, with a lower intermediate member 383 interposed between these downward step portion D3 and upward step portion D4.

[0057] This lower intermediate member 383 is composed of, for example, a pair of halved elements obtained by cutting a ring plate in half, and its inner diameter is equal to the outer diameter of the upward step portion D4 formed on the outer circumferential surface 332b on the other end opening side of the outer furnace body 332.

[0058] As an example of a connection method for connecting the introduction-side flange portion 37 to the other end opening side of the outer furnace body 332, the following procedure can be given.

[0059] First, the fourth element 382 is passed through the other end opening of the outer furnace body 332, and each of the pair of split elements is fitted onto the upward step portion D4 formed on the outer peripheral surface of the other end opening of the outer furnace body 332 to form an annular lower intermediate member 383. Next, this lower intermediate member 383 is sandwiched between the upward step portion D4 and the downward step portion D3 of the fourth element 382, ​​and the fourth element 382 is fixed to the third element 381 with fasteners B2.

[0060] The vaporization member 34 is located inside the inner furnace body 331 and vaporizes the liquid sample. In this embodiment, it is, for example, a granular body made of ceramics.

[0061] In this embodiment, the combustion reaction section 32 is further equipped with a catalyst Z below the vaporization member 34, as shown in Figures 5 and 6.

[0062] This catalyst Z is a layered structure made of a different material from the vaporizing member 34, such as CeO2 (cerium oxide), CuO (copper oxide), Pt (platinum), Pd (palladium), or ZrO2 (zirconia), and is positioned in contact with the vaporizing member 34. By providing such a catalyst, the combustion efficiency of organic matter in the liquid sample can be improved, and consequently, the measurement accuracy can be improved. In addition to this layered catalyst Z, another catalyst layer may be provided inside or above the vaporizing member 34, or the catalyst may be mixed (added) to all or part of the vaporizing member 34.

[0063] As shown in Figure 5, the holding member 35 is located below the vaporizing member 34 of the inner furnace body 331 and holds the granular material in the axial center of the combustion furnace body 33. This holding member 35 is made of ceramic and has passage channels for passing gas generated from the liquid sample. Specific examples include honeycomb plates with multiple passage channels.

[0064] In this embodiment, as shown in Figure 6, the inner furnace body 331, the vaporization member 34, and the holding member 35 are integrated into a single unit and are configured to be detachably attached to the outer furnace body 332 as a whole. To facilitate attachment and detachment, one or more holes h are provided in the upper part of the inner furnace body 331, and other members can be hooked into these holes h. However, the inner furnace body 331, the vaporization member 34, and the holding member 35 do not necessarily need to be unitized.

[0065] The heating mechanism 36 has a heater surrounding the axial center of the outer furnace body 332 and heats the vaporizing member 34 to, for example, about 1000°C. However, the heating temperature may be lowered by using a catalyst.

[0066] [Dehumidifying Unit 40] As shown in Figure 2, the dehumidification unit 40 includes a dehumidifier 41 to which the gas generated by the combustion reaction unit 30 described above is introduced, and an absorber 42 that removes the corrosive gas, which is the vaporized acid used in the pretreatment described above, from the gas after it has passed through the dehumidifier 41.

[0067] More specifically, as shown in Figure 7, the dehumidification unit 40 has a support 43 with a roughly U-shaped cross-section, which has a pair of side plates 431 and a front plate 432 connecting the pair of side plates 431. Various components that make up the dehumidification unit 40, such as a dehumidifier 41 and an absorber housing 44, are supported on this support 43. In this embodiment, the support 43 is made by bending a single sheet of metal, and replacement parts that are removed during maintenance are attached to the front surface 43a of the front plate 432, while standard parts such as piping, electrical wiring, and connectors are attached to the back surface 43b of the front plate 432.

[0068] The gas that has passed through the dehumidification unit 40 is guided to the carbon dioxide detection unit X after passing through a filter, as shown in Figure 2. The carbon dioxide detection unit X here is equipped with a detector that detects carbon dioxide contained in the combustion gas by, for example, NDIR (non-dispersive infrared absorption spectroscopy), and is located near the control unit 50. However, the type and arrangement of the detector are not limited to this and may be changed as appropriate.

[0069] [Control Unit 50] Physically, the control unit 50 is a dedicated or general-purpose computer equipped with a CPU, memory, AD converter, input / output means, etc. Functionally, it operates according to an analysis program stored in a predetermined area of ​​the memory, and at least performs the function of calculating the amount and concentration of total organic carbon contained in a liquid sample based on the light intensity signal detected by the detection unit described above.

[0070] According to the total organic carbon meter 100 described above, since the catalyst Z is positioned below the vaporizing member 34, there is no need to raise the sample vaporized by the vaporizing member 34 towards the catalyst. This allows the vaporizing member 34 and the catalyst Z to be positioned closer together, improving the combustion efficiency of organic matter in the liquid sample and, consequently, improving measurement accuracy.

[0071] Furthermore, since the catalyst Z is positioned in contact with the vaporizing member 34, the catalyst Z and the vaporizing member 34 can be positioned without an air layer in between them, thus making the improvements in combustion efficiency and other aspects mentioned above more effective.

[0072] Furthermore, since the heating furnace body has an inner furnace body 331 into which the liquid sample is introduced and an outer furnace body 332 surrounding the inner furnace body 331, the inner furnace body 331 can suppress cracking and other damage caused by the expansion of the outer furnace body 332. Furthermore, since the inner circumferential surface 332a of the outer furnace body 332 has the same cross-sectional shape as a straight tube from one end opening to the other end opening, the outer furnace body 332 can be easily molded by processes such as drawing, thereby improving workability.

[0073] Furthermore, the inner furnace body 331, the vaporization member 34, and the holding member 35 are integrated into a single unit and are configured to be detachably attached to the outer furnace body 332 as a whole. This improves maintainability, such as the replacement of the vaporization member 34.

[0074] Furthermore, since a resin sample introduction tube 311 is used, a predetermined amount of liquid sample can be introduced into the combustion furnace body 33 without any remaining in the sample introduction tube 311. Moreover, since the sample introduction tube 311 is cooled by the cooling mechanism, thermal damage to the sample introduction tube 311 can be prevented.

[0075] In addition, since the sampling unit 20, the combustion reaction unit 30, the dehumidification unit 40, and the control unit 50 are separated, the degree of freedom in arranging each unit can be improved.

[0076] However, the present invention is not limited to the embodiments described above.

[0077] For example, a gas return mechanism 39 may be provided upstream of the combustion reaction section 32, as shown in Figure 8, to return the gas flowing out of the combustion reaction section 32 back into the combustion reaction section 32. The gas return mechanism 39 may also be provided downstream of the combustion reaction section 32.

[0078] One example of this gas return mechanism 39 is shown in Figure 8, in which the gas vaporized in the combustion reaction section 32 is returned to the sample introduction tube 311, and then returned to the combustion reaction section 32 again via the sample introduction tube 311. In this case, a specific configuration may be provided that includes a backflow channel 39L communicating with the sample introduction tube 311, and a pump P provided in the backflow channel 39L.

[0079] Another example of the gas return mechanism 39 is a configuration in which the gas discharged from the combustion reaction section 32 is returned to the combustion reaction section 32 without being passed to the dehumidification unit 40. In this case, a specific configuration could be described as one that includes a circulation channel and a switching valve for selectively passing the gas to either the circulation channel or the dehumidification unit 40.

[0080] The combustion reaction section 32 may also be equipped with a position adjustment mechanism for adjusting the position of the sample introduction tube 311 relative to the heating furnace body. Specifically, examples of position adjustment mechanisms include those utilizing a moving stage, and those configured to allow adjustment of the position of the sample introduction tube 311 so that the tube axis of the sample introduction tube 311 is located on the central axis of the inner furnace body 331.

[0081] Furthermore, the combustion reaction unit 30 may also include, for example, a mounting platform located at the bottom of the heating furnace body on which used vaporizing members 34 can be temporarily placed when the vaporizing members 34 are replaced.

[0082] In the above embodiment, the supports 24 and 43 constituting the sampling unit 20 and the dehumidification unit 40 were described as having a roughly U-shaped cross-section, but the shape of the supports 24 and 43 is not limited to this, and they may also have a roughly L-shaped cross-section, for example.

[0083] Although the vaporizing member 34 in the above embodiment was described as a granular body made of ceramics, the shape and material of the vaporizing member 34 may be changed as appropriate, for example, by using a flat plate-shaped vaporizing member made of ceramics.

[0084] Here, a specific embodiment for measuring a predetermined amount of liquid sample using the sample measuring unit 31 is shown in Figure 9, which includes a liquid sample line L1 with one end connected to the sample container 21 and the other end connected to the sample measuring unit 31, a pump P such as a tubing pump provided on the liquid sample line L1, a three-way valve V0 provided on the liquid sample line L1, and an introduction line L2 connected to the liquid sample line L1 via the three-way valve V0 to guide the measured liquid sample to the combustion reaction unit 32.

[0085] With the configuration described above, the liquid sample stored in the sample container 21 is pressurized by the pump P and sent to the sample metering unit 31, so that a predetermined amount of liquid sample remains in the piping T from the three-way valve V0 to the sample metering unit 31 in the liquid sample line L1. Then, by switching the three-way valve V0, this predetermined amount of liquid sample can be guided to the combustion reaction unit 32 via the introduction line L2.

[0086] However, with the above configuration, the pulsation of the pump P causes the liquid sample to fill or not fill the tip of the pipe T connected to the sample measuring unit 31, resulting in variability in the amount of liquid that fills the pipe T, i.e., the amount of liquid after measuring. In addition, droplets may adhere to the tip of the pipe T, and these droplets will further cause variability in the amount of liquid.

[0087] Therefore, the total organic carbon analyzer 100 according to the present invention may be configured to send a liquid sample to the sample metering unit 31 using a carrier gas, as shown in Figure 10. More specifically, a branch line L4, which branches off from the carrier gas line L3 that supplies carrier gas to the sample weighing unit 31 and is connected to the sample container 21, and the aforementioned liquid sample line L1 are connected by a connecting line L5. This branch line L4 is a line for removing inorganic carbon from the liquid sample stored in the sample container 21 by sending carrier gas to the sample container 21. Furthermore, one end of the connecting line L5 does not necessarily have to be connected to the branch line L4, but may also be connected to the carrier gas line L3.

[0088] In the configuration described above, the connection line L5 and the branch line L4 are connected via the first three-way valve V1, and the connection line L5 and the liquid sample line L1 are connected via the second three-way valve V2. Furthermore, an on / off valve V3, such as a solenoid valve, is provided either upstream or downstream of the second three-way valve V2 in the liquid sample line L1.

[0089] Next, we will explain the weighing method using the configuration described above.

[0090] First, the pump P sends the liquid sample stored in the sample container 21 to the sample weighing unit 31.

[0091] Subsequently, the pump P is stopped, and the first three-way valve V1 and the second three-way valve V2 are switched to send the carrier gas to the liquid sample line L1 via the connection line L5. At this time, the on / off valve V3 is in the open state.

[0092] As a result, the carrier gas flowing through the liquid sample line L1 pushes the liquid sample into the sample metering unit 31.

[0093] Next, by closing the on / off valve V3, a predetermined amount of liquid sample remains in the piping T from the three-way valve V0 to the sample metering unit 31 in the liquid sample line L1.

[0094] Next, carrier gas is introduced into the sample weighing unit 31 via the carrier gas line L3, pressurizing the inside of the sample weighing unit 31.

[0095] Then, by switching the three-way valve V0 of the liquid sample line L1, a predetermined amount of liquid sample remaining in the aforementioned piping T is guided to the combustion reaction section 32 by the internal pressure of the sample metering unit 31.

[0096] With this configuration, the carrier gas pushes the liquid sample to the sample metering unit 31, and since there is no pulsation in the flow velocity of this carrier gas, the liquid sample can be delivered to the sample metering unit 31 at a constant speed. Furthermore, since the on-off valve V3 is closed while the liquid sample is being pushed into the sample metering unit 31, it is possible to prevent liquid droplets from remaining at the tip of the piping T as described above. As a result, a predetermined amount of liquid sample can be reproducibly left in this pipe T, and the liquid sample can be accurately measured.

[0097] However, in the total organic carbon meter 100 according to the present invention, various components such as multiple valves and sample weighing units 31 are connected by numerous pipes. For example, when a user assembles each unit 20 to 50, there is a risk that they may mistakenly connect a component to a component other than the one they are supposed to connect. This can lead to malfunctions such as incorrect weighing, and the measurement accuracy cannot be guaranteed.

[0098] Therefore, the total organic carbon meter 100 according to the present invention may be configured to allow confirmation of the connections between each unit 20 to 50 after assembly of each unit 20 to 50, and in this case, it is configured to allow confirmation of whether the connection between the sampling unit 20 and the combustion reaction unit 30 is correct or incorrect.

[0099] A specific embodiment involves introducing gas into a diagnostic area that includes one or more connection points (specifically, piping components) connecting the sampling unit 20 and the combustion reaction unit 30, while simultaneously creating a closed space within the diagnostic area and measuring the pressure within that area. The pressure can be measured using a pressure sensor mounted on the detection unit X, or a separate pressure sensor can be provided for measuring the pressure in the diagnostic area.

[0100] The connection points between the sampling unit 20 and the combustion reaction unit 30 are piping that connects the components of the sampling unit 20 and the components of the combustion reaction unit 30. Specifically, in Figure 10, these include piping that connects the combustion reaction section 32 and the three-way valve V0, piping that connects the second three-way valve V2 and the on-off valve V3, and piping that is connected to the sample metering section 31 and introduces a liquid sample or carrier gas.

[0101] Then, the actual pressure in the diagnostic area at the time of diagnosis is compared with the reference pressure, which is the pressure of the area to be diagnosed that was previously acquired under normal conditions. If, for example, the difference or ratio between the reference pressure and the measured pressure exceeds a predetermined threshold, it is determined that there is a malfunction or error in the piping connection included in that diagnostic area. This determination may be made by an operator, or it may be made possible to automate the diagnosis by equipping a control unit 50 or the like with this diagnostic function.

[0102] By switching the opening and closing of various valves V0 to V3, the diagnostic area can be changed, and by performing the aforementioned diagnostics for each diagnostic area, the faults and incorrect connection points can be narrowed down. Of course, the valves that can be switched are not limited to valves V0 to V3 shown in Figure 10; valves (not shown) installed in various locations can also be switched.

[0103] Furthermore, it goes without saying that the present invention is not limited to the embodiments described above, and various modifications are possible without departing from its spirit. [Industrial applicability]

[0104] In the present invention, in a configuration in which a sample vaporized by a vaporizing member is passed through a catalyst, the vaporizing member and the catalyst can be placed close together.

Claims

1. A total organic carbon meter for measuring the total organic carbon contained in a liquid sample, A combustion reaction section that burns all the organic carbon contained in the liquid sample to generate carbon dioxide, A carbon dioxide detection unit for detecting carbon dioxide generated by the combustion reaction unit, A sample introduction tube for introducing the liquid sample into the combustion reaction section, It has a cooling mechanism for cooling the sample introduction tube, The aforementioned combustion reaction section is The combustion furnace body, A vaporizing member housed inside the combustion furnace body, A holding member which holds the vaporizing member and is a honeycomb plate having a plurality of passage channels, A heating mechanism for heating the vaporizing member, The vaporizing member comprises a catalyst positioned below the vaporizing member, The sample introduction tube is made of resin, or of ceramic or metal with a water-repellent coating on its inner surface, in a total organic carbon analyzer.

2. The total organic carbon meter according to claim 1, wherein the catalyst is in contact with the vaporizing member inside the combustion furnace body.

3. The total organic carbon meter according to claim 1 or 2, wherein the vaporizing member and the catalyst are made of different materials.

4. The aforementioned combustion furnace body is The inner furnace body into which the liquid sample is introduced, A total organic carbon analyzer according to any one of claims 1 to 3, comprising an outer furnace body surrounding the inner furnace body.

5. The total organic carbon meter according to claim 4, wherein the outer furnace body has a straight tubular shape with the same cross-sectional shape on its inner circumferential surface from one end opening to the other end opening.

6. The vaporizing member is a granular body made of ceramics, The heating mechanism has a heater surrounding the axial central portion of the outer furnace body, The total organic carbon meter according to claim 4 or 5, wherein the holding member is provided inside the inner furnace body and holds the granular material in the axial center of the combustion furnace body.

7. The total organic carbon meter according to claim 6, wherein the holding member has a passage for passing gas generated from the liquid sample.

8. The total organic carbon meter according to claim 7, wherein the inner furnace body, the vaporization member, and the holding member are unitized and configured to be detachably attached to the outer furnace body as a whole.

9. The outer furnace body has a metal introduction flange portion connected to the end on the one-end opening side. The sample introduction tube is connected to the introduction side flange portion. The total organic carbon analyzer according to any one of claims 5 to 8, wherein the cooling mechanism is provided outside the introduction flange portion and is configured to cool the sample introduction tube by cooling the introduction flange portion.

10. The total organic carbon analyzer according to any one of claims 5 to 8, wherein the outer furnace body has a metal inlet flange detachably connected to the end on the one-end opening side and a metal outlet flange detachably connected to the end on the other-end opening side.

11. A total organic carbon meter according to any one of claims 1 to 10, wherein a gas return mechanism is provided downstream of the combustion reaction section to return the gas flowing out of the combustion reaction section back to the combustion reaction section.

12. A sampling unit for sampling the liquid sample, A combustion reaction unit having the aforementioned combustion reaction section, A dehumidification unit having a dehumidification section for dehumidifying the gas flowing out from the combustion reaction section, The total organic carbon meter according to any one of claims 1 to 11, wherein the total organic carbon meter is separated from a control unit having a control unit for controlling the total organic carbon meter.

13. The total organic carbon meter according to claim 12, wherein any one of the units has a support having a roughly U-shaped cross-section with a pair of side plates and a front plate connecting the pair of side plates, and the components constituting the unit are supported on the support.

14. The system further includes a diagnostic function for diagnosing the connection point between the sampling unit and the combustion reaction unit. The total organic carbon meter according to claim 12 or 13, wherein the diagnostic function diagnoses the connection point by comparing the actual pressure, which is the pressure when gas is flowed into the diagnostic area including the connection point, with the reference pressure, which is the pressure when gas is flowed into the diagnostic area under normal conditions.

15. A combustion reaction unit used in a total organic carbon analyzer for measuring the total organic carbon contained in a liquid sample, which burns the total organic carbon contained in the liquid sample to generate carbon dioxide, The combustion furnace body, The combustion furnace body includes a sample introduction tube for introducing the liquid sample, A cooling mechanism for cooling the sample introduction tube, A vaporizing member housed inside the combustion furnace body, A holding member which holds the vaporizing member and is a honeycomb plate having a plurality of passage channels, A heating mechanism for heating the vaporizing member, The vaporizing member comprises a catalyst positioned below the vaporizing member, The aforementioned sample introduction tube is made of resin, or of ceramic or metal with a water-repellent coating on its inner surface, in a combustion reaction unit.

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