JP2001249140A - Dropping device, oxidation reaction device and analysis device using the same - Google Patents

Abstract

(57) [Problem] To provide an analyzer for oxidizing and measuring a sample liquid to continuously obtain measurement data. Therefore, the sample liquid can be supplied as a very small amount of droplets,
Provided are a liquid dropping device in which liquid replacement is quick, and an oxidizing device capable of oxidizing a sample liquid in a short time. SOLUTION: A nozzle 1 through which a sample liquid flows, a nozzle 1
A pump 6 for continuously supplying a sample liquid to the nozzle 1, a shield 11 below the nozzle 1 and having a slit 12, and a motor 14 for driving the shield 11 are provided. By driving, a small amount of droplets are intermittently supplied to the combustion tube 31 from a droplet dropping device that limits the time during which the slit 12 in the shield 11 is located immediately below the tip of the nozzle 1. The sample liquid burns in the combustion tube 31 to become a sample gas. This sample gas is analyzed by the analysis unit 42.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid dropping device suitable for dropping a small amount of a sample liquid, an oxidation reaction device using the same, and an analyzer for measuring a sample liquid by burning and oxidizing the same. More specifically, analyzers for determining total nitrogen, total organic carbon, total oxygen demand, and the like by measuring nitrogen monoxide, carbon dioxide, oxygen, and the like contained in the gas obtained by burning the sample liquid, and The present invention relates to a droplet dropping device and an oxidation reaction device that can be suitably used for the present invention.

[0002]

2. Description of the Related Art From the viewpoint of preventing eutrophication of closed water bodies,
It is required to control the total amount of nitrogen in the inflow and outflow of public water and wastewater treatment facilities. Also, an index representing the amount of organic matter in various sample liquids, such as raw water and treated water of sewage and sewage, inflow and outflow of wastewater treatment, environmental water such as rivers and lakes, washing water, and various types of plant water such as cooling water. As the total oxygen demand (TO
D) and total organic carbon (TOC) are used.

[0003] As an analyzer for the total nitrogen, total organic carbon, and total oxygen demand, there is known an apparatus for measuring nitrogen monoxide, carbon dioxide, oxygen or the like contained in a gas obtained by burning a sample liquid. I have. Specifically, in the total nitrogen analyzer,
Nitrogen in the sample liquid is oxidized to nitric oxide, and the total amount of nitrogen in the sample liquid is analyzed by measuring the nitric oxide in a chemiluminescent gas analyzer. In addition, the total organic carbon analyzer oxidizes the carbon in the sample solution to carbon dioxide, and measures the carbon dioxide in the infrared gas analyzer to obtain
Analyze the total organic carbon in the sample solution. In the total oxygen demand analyzer, the total oxygen demand of the sample liquid is analyzed by measuring the amount of oxygen consumed when the sample liquid is burned by the oxygen gas analyzer.

As an oxidizing device for burning a sample liquid, a combination of a combustion tube into which the sample liquid is introduced and a heating device for heating the same is used. The combustion tube is usually filled with a catalyst for assisting combustion, and a carrier gas is introduced. The carrier gas supplies oxygen gas necessary for combustion into the combustion tube and introduces the burned gas into the analyzer.

The smaller the amount of the sample liquid introduced into the combustion tube, the more it can be completely burned in a shorter time.
For this reason, a sample liquid is dripped into a combustion tube as a very small amount of liquid droplet using a liquid dropping device.

Conventionally, in a total nitrogen analyzer or the like, a slider valve type dropping device has been used in which a minute length portion of a circulating sample liquid stream is cut off by a slider valve and supplied to a nozzle. FIG. 8 is an example of a total nitrogen analyzer using a valve type dropping device as a slider.

In FIG. 8, reference numeral 101 denotes a slider valve,
A slider 104 is slidably inserted between the upper plate 102 and the lower plate 103. The slider 104 has flow paths 104a, 1
04b and 104c are formed, and the position with respect to the upper plate 102 and the lower plate 103 can be changed in the horizontal direction by the driving device 105.

In the upper plate 102, flow paths 104a,
Tube mounting holes that can communicate with 104b and 104c are formed. In the illustrated position, a tube forming the sample flow path 111 is mounted in a mounting hole communicating with the flow path 104a. In addition, a tube forming the gas flow path 121 is mounted in a mounting hole communicating with the flow path 104b. Further, a tube forming the cleaning liquid flow path 131 is mounted in the mounting hole communicating with the flow path 104c.

Similarly, the flow path 10 is also provided in the lower plate 103.
Tube mounting holes that can communicate with 4a, 104b, and 104c are formed. In the illustrated position, the flow path 104a
A tube forming the sample channel 112 is attached to the attachment hole communicating with the tube. In addition, a tube having a nozzle 122 at its tip is attached to the attachment hole communicating with the flow path 104b. Further, a tube forming the cleaning liquid flow path 132 is mounted in the mounting hole communicating with the flow path 104c.

A sample liquid flow path 114 and a standard liquid flow path 115 are connected to the sample liquid flow path 112 via a switching valve 113, and a pump 116 provided in the sample liquid flow path 111 is provided.
By operating, either the sample liquid or the standard liquid is introduced, and is discharged after passing through the slider valve 101. Note that 117 is the sample liquid flow path 1
14 is a defoaming tank. In addition, the gas passage 121
, The carrier gas purified by the air purification column 123 is supplied through the on-off valve 124. The ends of the cleaning liquid flow paths 131 and 132 are respectively inserted into the cleaning liquid flow path 133, and the pump 134 disposed in the cleaning liquid flow path 132 is operated so that the cleaning liquid in the cleaning liquid flow path 133 causes the slider valve 101 to move. It is designed to discharge while passing.

The tip of the nozzle 122 is inserted into the upper end of the reaction tube 141. The catalyst 1 is contained in the reaction tube 141.
The sample liquid dropped inside the reaction tube 141 is oxidized by heating in the heating furnace 143. The sample gas where the sample liquid is oxidized,
The lower end of the reaction tube 141 is introduced into the sample gas tube 151 via a dehumidifying unit 152. In addition,
Reference numeral 153 denotes a trap for absorbing a sudden volume expansion accompanying the gasification of the sample liquid and discharging the water removed by the dehumidifying unit 152.

A chemiluminescent cell 161 is provided at the end of the sample gas tube.
Is provided. An ozone generator 162 generates ozone gas using a carrier gas as a material, and supplies the ozone gas to the chemiluminescence cell 161. Also, a pump 163 is used to introduce the sample gas into the chemiluminescent cell 161.
Are provided on the exit side of the chemiluminescent cell 161. An ozone decomposition tank 164 for decomposing excess ozone gas is interposed between the chemiluminescent cell 161 and the pump 163.

In this total nitrogen analyzer, first, the pump 1
With the 16 operated, the slider 104 of the slider valve 101 is kept at the illustrated position, and the sample liquid is passed through the flow path 104a. At this time, the cleaning liquid is passing through the flow path 104c by the pump 134. Thereafter, when the slider 104 is shifted to the right, the flow path 10 filled with the sample liquid is moved.
4a comes to a position communicating with the nozzle 122. In this state, the on-off valve 124 is opened to allow the carrier gas to flow through the gas passage 1.
When supplied from 21, the sample liquid filling the flow path 104 a is extruded and drops from the nozzle 122 onto the reaction tube 141. At this time, the cleaning liquid is flowing through the flow path 104b. Thereafter, when the slider valve 104 is returned to the position shown in the figure, the flow path 10
4b comes. Then, in this state, the on-off valve 124 is opened, and the carrier gas is supplied from the gas channel 121. Then, the cleaning water filling the flow path 104b is pushed out, and drops into the reaction tube 141 while cleaning the inside of the nozzle 122. After that, the operation from the beginning is repeated.

The sample liquid dropped into the reaction tube 141 is heated and oxidized in the heating furnace 143 to become a sample gas. At this time, nitrogen in the sample liquid becomes nitric oxide gas. Chemiluminescent cell 1
In 61, the nitric oxide in the sample gas reacts with the ozone gas to generate chemiluminescence. By detecting this, the nitrogen in the sample solution can be analyzed.

On the other hand, in addition to the slider valve type liquid dropping device, a piezo pump conventionally used for application of a small amount of chemicals is known. The principle of the piezo pump will be described with reference to FIG. In the piezo pump 200, a pump chamber 204 is formed between an inlet 202 and an outlet 203 each having a check valve 201 for stopping the flow in the downward direction in the drawing. The pump chamber 204 is open at a central portion thereof, and the opened portion is closed by a diaphragm 205. The holding bar 206 presses the diaphragm 205. The holding rod 206 is given a pulling force by the spring 207 in a direction away from the diaphragm 205. Further, the laminated piezoelectric actuator 2 transmitted by the connecting rod 208
A stretching force of 09 is also provided.

In the piezo pump 200, when a driving voltage is applied to the laminated piezoelectric actuator 209, the entire length thereof is slightly increased. This extension is expanded by the connecting bar 208 and transmitted to the holding bar 206, and a pressing force is applied to the diaphragm 205. When the driving voltage is cut off, the connecting rod 2
By utilizing the tensile force of the spring 207 transmitted at 08, the length of the laminated piezoelectric actuator 209 is returned to the original length, and the pressing force of the pressing bar 206 on the diaphragm 205 is also eliminated. Therefore, every time the drive voltage is turned on / off once, the liquid corresponding to the volume fluctuation of the pump chamber 204 is transferred from the inlet 202 to the outlet 203,
It can be dropped every drop.

[0017]

In the slider valve 101 shown in FIG. 8, the amount of one drop is usually about 30 μm.
Before and after L, even if the device is formed as small as possible, about 20
Droplets can only be reduced to around μL.
Therefore, it takes one minute or more for one drop of the sample liquid to completely burn in the reaction tube 141, and when the washing step is included, the dropping of the next sample liquid must be performed within about 4 minutes. Can not. Therefore, the analysis of the sample liquid cannot be performed continuously.

Since the sample gas generated over one minute or more is sequentially introduced into the chemiluminescent cell 161, the chemiluminescence in the chemiluminescent cell 161 is also reduced to 1 as shown in FIG.
Continue for more than a minute. Therefore, unless this continuous chemiluminescence is integrated, nitrogen in the sample solution cannot be obtained, and a complicated data processing mechanism is required.

Further, since the slider valve 101 is a device that is precisely rubbed and the rubbing portion is driven, it is difficult and expensive to manufacture, and there is a high risk of failure. Further, the carrier gas for extruding the droplet needs to flow gently enough to allow the droplet to freely fall. This is because if the droplets fly out vigorously, they are scattered. Therefore, since it is difficult to give the droplet an initial velocity, the droplet may not be introduced straight into the reaction tube 141 due to the influence of static electricity. In this case, the droplet adheres to the wall surface of the reaction tube 141. It may remain unburned and cause a measurement error.

On the other hand, the piezo pump 200 shown in FIG.
In this case, the amount of one drop can be reduced to about 1 μL. With a sample solution of about 1 μL, the reaction tube 141 can be completely burned in a short time without imposing too much load on the reaction tube 141. Therefore, the next sample liquid can be dropped after about 4 seconds. In that case, the chemiluminescence in the chemiluminescent cell 161 is also observed as a substantially continuous signal, and it is considered possible to simplify the data processing mechanism. Further, since the droplet is dropped at an initial velocity, there is an advantage that the droplet is easily introduced straight into the reaction tube 141.

However, when this piezo pump 200 was used in place of the slider valve 101 in a total nitrogen analyzer as shown in FIG. 8, it was found that it took a very long time to replace the liquid. That is, even if the pipes at both the inlet and the outlet of the piezo pump 200 are formed as thin and short as possible, the total volume of these pipes and the piezo pump 200 itself is about 500 μL. Therefore, it takes 30 minutes or more for the sample liquid introduced from the inlet pipe to be dropped from the tip of the outlet pipe, assuming that 1 μL is dropped once every 4 seconds.

For this reason, even if the concentration of the sample liquid changes on the inlet side, it can be detected on the analyzer side after 30 minutes or more. This causes not only the problem of data time lag but also the problem of extremely long maintenance work. That is, as shown in FIG. 8, even if a mechanism for switching between the sample and the standard solution is provided, the calibration work must be started after waiting for 30 minutes or more as the time required for replacing the sample with the standard solution. . Therefore, although the piezo pump has the advantage of obtaining a small amount of droplets, it has been practically difficult to use it for supplying a sample liquid.

The present invention has been made in view of the above circumstances, and a first object of the present invention is to supply a sample liquid as a very small amount of liquid droplets, to quickly replace the liquid, and to manufacture the liquid with a simple configuration at a low cost. It is an object of the present invention to provide a dropping device.
A second object is to provide an oxidation reaction apparatus that can oxidize a sample solution in a short time, can quickly respond to replacement of the sample solution, and can be manufactured at a low cost with a simple configuration. . A third object is that measurement data of a sample liquid can be obtained continuously or intermittently at short intervals, the replacement of the sample liquid is good, and a complicated data processing mechanism and a mechanical configuration are not required. It is an object of the present invention to provide an analyzer which can be manufactured at low cost and can measure with high accuracy.

[0024]

Means for Solving the Problems In order to solve the above problems, the present inventor has proposed, as an invention according to claim 1, a nozzle through which a sample liquid flows, and a liquid feeder for continuously supplying the sample liquid to the nozzle. Means, a shield which is located below the nozzle and has a region through which the sample liquid can partially pass, and a drive means for driving the shield, and the shield is driven by the drive means, so that the Provided is a liquid dropping device that limits the time during which a region through which a sample liquid can pass is located immediately below a tip of a nozzle.

According to the present invention, a continuously flowing sample liquid stream is chopped by a shield having an area through which the sample liquid can partially pass, thereby forming fine droplets. It is possible. Further, since the sample liquid flowing out of the nozzle is continuous, the liquid replacement is quick. The size of the droplet is controlled by the time during which the region through which the sample liquid can partially pass is located immediately below the nozzle, that is, by the size of the region through which the sample liquid can partially pass and the moving speed of the shield. be able to.

In the first aspect of the present invention, the shield does not necessarily need to be physically composed of a single member, but the sample is formed by the gap between the two shield units separated as in the second aspect of the present invention. It may be a shield in which a region through which the liquid can pass is formed. In this case, it is necessary to keep the gap between the two shielding units constant in order to keep the region through which the sample liquid can pass.

According to the first or second aspect of the present invention, as described in the third aspect, the area of the shield that allows the sample liquid to pass therethrough has a slit shape, and the driving means connects the shield with the slit. It is desirable to drive in a right angle or substantially right angle direction. Accordingly, the size of the droplet can be controlled by the time during which the slit is located immediately below the nozzle, that is, the slit width and the moving speed of the slit. In this case, since the shield is driven in the width direction of the slit, even when the driving direction does not maintain a strictly right angle with respect to the slit, the time that the slit is located immediately below the tip of the nozzle is substantially ignored. It can be constant within a possible fluctuation range.

In the liquid dropping device according to any one of the first to third aspects, the shield may be driven by a linear drive or a curved drive such as rotation. Of these, when driving to rotate,
Intermittent dropping is possible without reciprocating movement.
That is, since the driving direction can be set to a single direction as described in claim 4, the temporarily shielded sample liquid is prevented from dropping directly below the nozzle due to the inertial force when the direction is changed. Cheap. As described above, when the shield is rotated in one direction by the driving unit, the shield may be intermittently rotated instead of being uniformly rotated.
In this case, independently of the time required for one rotation, the moving speed at which the slit crosses directly below the nozzle can be adjusted. For this reason, it is possible to independently control the drop interval and the size of one drop.

On the other hand, when the shield is driven in the linear direction by the drive means, the shield must be reciprocated for intermittent dropping. In this case, as described in claim 6, it is desirable that the shield is constituted by two shield units in which a gap between them is kept constant, and that a rotating means for rotating the respective shield units is provided. This allows the shielded sample liquid to move in the rotation direction, thereby preventing the temporarily shielded sample liquid from dropping directly below the nozzle due to the inertial force when the direction is changed.

The danger that the sample liquid once shielded falls directly below the nozzle may be such that the upper surface of the shield is inclined with respect to the horizontal plane as described in claim 7 or as described in claim 8.
By providing a wiper for removing the sample liquid adhering to the surface of the shield other than immediately below the nozzle, it can be more effectively prevented.

According to the present invention, the present invention is also directed to a ninth aspect of the present invention, in which a nozzle through which a sample liquid flows, a liquid feeding means for continuously supplying the sample liquid to the nozzle, and a partial nozzle located below the nozzle. A shield having an area through which the sample liquid can pass, and driving means for driving the tip of the nozzle, and the driving means driving the tip of the nozzle causes the area of the shield to allow the sample liquid to pass through the tip of the nozzle. A dropping device characterized by limiting the time located immediately below the dropping device.

According to the present invention, the continuously flowing sample liquid flow is chopped by the shield by moving the nozzle side instead of the shield, and the chopped droplet is dropped as minute droplets. Also in this case, since the sample liquid flow flowing out of the nozzle is continuous, the liquid is quickly replaced. The size of the droplet is controlled by the time during which the area through which the sample liquid can partially pass is located immediately below the nozzle, that is, the size of the area through which the sample liquid can partially pass and the moving speed of the tip of the nozzle. be able to.

The invention according to claim 9 is the first invention.
As described in Item 0, it is desirable that the region of the shield through which the sample liquid can pass has a slit shape, and that the driving means drives the tip of the nozzle in a direction perpendicular or substantially perpendicular to the slit. Thus, the size of the droplet can be controlled by the time during which the slit is located immediately below the tip of the nozzle, that is, the slit width and the moving speed of the tip of the nozzle. In this case, since the tip of the nozzle is driven in the width direction of the slit, even if the driving direction is slightly deviated, the time for the slit to be located immediately below the nozzle,
It can be constant within a substantially negligible variation range.

In the case where the tip side of the nozzle is driven, the danger that the sample liquid once shielded falls directly below the nozzle is reduced by inclining the upper surface of the shield with respect to the horizontal plane. , Can be effectively prevented.

The present inventor also provides a combustion tube having an inlet and an outlet, a droplet supply means for supplying droplets of a sample liquid to the inlet of the combustion tube, Carrier gas supply means for supplying a carrier gas to the inlet;
A heating means for heating the combustion tube is provided, and the droplet supply means is the droplet dropping device according to any one of claims 1 to 11. According to the present invention, since the sample liquid can be dropped as a minute amount of droplets,
It can be oxidized in a short time. Further, it is possible to quickly respond to the replacement of the sample liquid. Furthermore, since the droplet has an initial velocity due to the dripping, the droplet is introduced straight into the combustion tube. Therefore, there is no possibility that the droplets adhere to the wall surface of the combustion tube and remain without being burned to cause an error.

According to a twelfth aspect of the present invention, as set forth in the thirteenth aspect, the carrier gas supply means includes a housing, and a gas inflow pipe through which the carrier gas flows into the housing. In this case, the shield of the dropping device is housed in an airtight manner, the tip of the nozzle of the droplet dropper and the inlet side of the combustion tube are inserted in an airtight manner, and the sample liquid removed by the shield is discharged. A configuration in which a water-sealed discharge port is provided can be suitably adopted. In this case, the carrier gas does not need to be supplied directly to the inlet of the combustion tube, so that the shape of the inlet of the combustion tube does not need to be complicated.

The present inventor further provides a combustion tube having an inlet and an outlet, a droplet supply means for supplying droplets of a sample liquid to the inlet of the combustion tube, Carrier gas supply means for supplying a carrier gas to the inlet;
12. The droplet supply means according to claim 1, further comprising: a heating unit for heating the combustion tube; and an analysis unit configured to generate a measurement signal by introducing a gas flowing out from an outlet side of the combustion tube. The present invention provides an analyzer characterized by being an apparatus for dropping liquid.

According to the present invention, since the sample liquid can be dropped as a very small amount of droplets, it can be oxidized in a short time.
Therefore, measurement data can be obtained intermittently or continuously at short intervals. Further, it is possible to quickly respond to the replacement of the sample liquid. Further, since the droplet is introduced straight into the combustion tube, accurate measurement can be performed without the droplet remaining without being burned.

The present inventor also provides a combustion tube having an inlet and an outlet, a droplet supply means for supplying droplets of a sample liquid to the inlet of the combustion tube, Carrier gas supply means for supplying a carrier gas to the inlet;
A heating unit that heats the combustion tube, and an analysis unit that generates a measurement signal by introducing a gas flowing out from the outlet side of the combustion tube, and the measurement signal obtained due to one droplet of the sample liquid is continued. The present invention provides an analyzer characterized in that the supply of droplets by the droplet supply means is performed continuously at intervals shorter than the time required for the analysis.

According to the present invention, by superimposing signals obtained from one drop of the sample liquid, it is possible to obtain measurement data that is continuously continuous as a whole. Therefore, the concentration of the target component in the sample liquid can be directly converted without integrating the measurement data, so that a complicated data processing mechanism is not required. In addition, the larger the overlap,
That is, as the supply interval of the droplets is shorter, data with less ripple can be obtained. However, the supply interval cannot be shortened so as to exceed the combustion capacity of the combustion tube.

The present inventor also provides a combustion tube having an inlet and an outlet, a droplet supply means for supplying droplets of a sample liquid to the inlet of the combustion tube, Carrier gas supply means for supplying a carrier gas to the inlet;
Heating means for heating the combustion tube, and an analyzer for introducing a gas flowing out from the outlet of the combustion tube to generate a measurement signal, and between the outlet of the combustion tube and the analyzer, the outlet of the combustion tube An analyzer is provided, wherein a buffer in which gas flowing out of the buffer temporarily stays is provided.

According to the present invention, the gas flowing out of the combustion tube is temporarily retained in the buffer, so that the combustion gas of the sample liquid is widely dispersed in the carrier gas, and the measurement data continuously continuous as a whole is obtained. Can be obtained.
Therefore, no complicated data processing mechanism is required. In this case, as the buffer is larger, data with less ripple can be obtained. However, if the buffer is too large, the response speed is delayed.

The present inventor also provides a combustion tube having an inlet and an outlet, a droplet supply means for supplying droplets of a sample liquid to the inlet of the combustion tube, Carrier gas supply means for supplying a carrier gas to the inlet;
A heating unit that heats the combustion tube, and an analysis unit that generates a measurement signal by introducing a gas flowing out from the outlet side of the combustion tube, and the measurement signal obtained due to one droplet of the sample liquid is continued. The droplets are continuously supplied by the droplet supply means at intervals shorter than the time required to perform the process, and the gas flowing out from the outlet side of the combustion tube temporarily flows between the outlet of the combustion tube and the analyzer. An analyzer provided with a buffer for staying is provided.

According to the present invention, the signal obtained from one drop of the sample liquid is superimposed, the gas flowing out of the combustion tube is temporarily retained in the buffer, and the combustion gas of the sample liquid is transferred to the carrier gas. The measurement data can be widely dispersed in the measurement data and continuously obtained as a whole.
Therefore, no complicated data processing mechanism is required. In this case, data with less ripple can be obtained due to the superposition of signals and the synergistic effect of the buffer.

In the invention according to any one of the fifteenth to seventeenth aspects, as described in the eighteenth aspect, the droplet supply means is provided with the droplet descent device according to any one of the first to eleventh aspects. It is desirable to do. In this case, since the droplets to be supplied to the combustion tube can be made very small, the supply interval of the droplets can be shortened without exceeding the combustion capacity of the combustion tube, and the capacity of the buffer can be reduced. Even if not so large, the combustion gas of the sample liquid can be sufficiently dispersed in the carrier gas. Therefore, the ripple can be reduced without significantly delaying the response time. Furthermore, as described in the fourteenth aspect of the present invention, it is possible to quickly respond to the replacement of the sample liquid, and since the droplets do not remain without burning, accurate measurement can be performed.

According to a fourteenth aspect of the present invention, as set forth in the nineteenth aspect, the carrier gas supply means includes a housing and a gas inflow pipe through which the carrier gas flows into the housing. The shield of the droplet dropping device is housed in the housing in an airtight manner, and the tip of the nozzle of the droplet dropping device and the inlet side of the combustion tube are hermetically inserted and removed by the shield. A mode in which a water-sealed outlet for discharging the sample liquid is provided can be suitably adopted. In this case, the carrier gas does not need to be supplied directly to the inlet of the combustion tube, so that the shape of the inlet of the combustion tube does not need to be complicated.

The invention according to any one of the fourteenth to nineteenth aspects can be configured as various specific analyzers by appropriately specifying the configuration of the analyzer. For example, if a chemiluminescent gas analyzer capable of measuring nitric oxide is provided as described in claim 20, a total nitrogen analyzer for a sample liquid can be obtained. In addition, if an infrared gas analyzer capable of measuring carbon dioxide is provided as described in claim 21, an apparatus for analyzing total organic carbon of a sample liquid can be obtained. In addition, if an oxygen gas analyzer for measuring oxygen is provided as described in claim 22, a total oxygen demand analyzer of the sample liquid can be obtained. In addition, as the oxygen gas analyzer,
A solid electrolyte fuel cell (zirconia battery), a liquid electrolyte fuel cell, a magnetic wind oxygen detector, and the like are used.

[0048]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration of a total nitrogen analyzer according to one embodiment of the present invention. In FIG. 1, a liquid supply pipe 2 is connected to a nozzle 1, and liquid is supplied to the liquid supply pipe 2 from a sample liquid supply pipe 4 or a standard liquid supply pipe 5 via a three-way valve 3. It is supposed to be.
The liquid supply pipe 2 is provided with a pump 6, and the sample liquid supply pipe 4 is provided with a defoaming tank 7.

Below the nozzle 1, a disk-shaped shield 11 is provided.
Are arranged substantially horizontally. The shield 11 is provided with a slit 12 and a rotating shaft 13 is integrally mounted at the center. The rotating force of the motor 14 is transmitted to the rotating shaft 13 via the belt 15 and the pulley 16. By operating the motor 14, the shield 11 can be rotated while the slit 12 passes just below the tip of the nozzle 1. In addition, on the upper and lower surfaces of the shield 11 at a position away from immediately below the nozzle,
A wiper 17 for wiping off the attached sample liquid is provided. Reference numeral 18 denotes a locus of the sample liquid, and shows a state in which the sample liquid flowing out of the nozzle 1 sequentially reaches the position of the wiper 17 on the upper surface side as the shield 11 rotates, and is wiped off there. In addition, the wiper 17 provided on the lower surface side of the shield 11 is for wiping off the sample liquid flowing to the lower surface side.

The shield 11 and the wiper 17 are accommodated in a housing 21, and the sample liquid wiped off by the wiper 17 falls on the bottom surface of the housing 21 and is discharged from a drain pipe 22. It has become. The tip of the drain pipe 22 is sealed by a trap 23 with water. The tip of the nozzle 1 is inserted into the housing 21, but the nozzle 1 is inserted into the housing 21 while keeping the airtight. The upper end of the rotating shaft 13 is
Although it protrudes to the outside, the confidentiality is also maintained at the insertion point of the rotating shaft 13.

Reference numeral 31 denotes a combustion tube having a main body 33 supporting a catalyst 32, an inlet pipe 34, and an outlet pipe 35. The inlet pipe 34 is located immediately below the nozzle 1 so that the droplets 37 that have passed through the slits 12 of the shield 11 pass therethrough.
Then, the droplets 37 fall onto the catalyst 32, and are burned and gasified by heating the electric furnace 38 at that location.

The tip of the outlet pipe 35 is connected to the trap 23
, So that rapid volume expansion accompanying gasification of the sample liquid can be absorbed. The sample gas obtained by oxidizing the sample liquid is introduced into the analyzer 42 via a sample gas pipe 41 branched from the outlet pipe 35.

The sample gas introduced into the analysis section 42 is dehumidified by the dehumidifier 44 by operating the pump 43, and then introduced into the chemiluminescence cell 45. A buffer 46 is appropriately interposed between the dehumidifier 44 and the chemiluminescent cell 45. In addition, the chemiluminescent cell 4
The ozone necessary for 5 is supplied from an ozone generator 47. Also, the chemiluminescent cell 45 and the pump 4
An ozone decomposing tank 48 for decomposing surplus ozone gas is interposed between the apparatus and the apparatus 3.

Air, which is a material gas of the carrier gas and the ozone gas, is introduced from an air supply passage 51 and is purified by an air purification column 52. The purified air is supplied to the carrier gas passage 53 and the material gas passage 5.
4 respectively. An opening / closing valve 55 is interposed in the carrier gas channel 53,
Its end is inserted into the housing 21 and the on-off valve 5
When the valve 5 is opened, the carrier gas can be supplied from the housing 21 to the analysis section 42 via the combustion tube 31. On the other hand, the clean air supplied to the material gas flow path 54 is introduced into the ozone generator 47 and is used as a material of the ozone gas.

In this total nitrogen analyzer, when the three-way valve 3 is on the sample liquid supply pipe 4 side, the sample liquid is continuously supplied to the nozzle 1 via the liquid supply pipe 2. Most of the sample liquid flowing out of the nozzle 1 is eliminated by the shield 11, but the shield 11 rotates and passes through the slit only when the slit 12 is located immediately below the nozzle.
Drop into.

The size of one drop of the sample liquid to be dropped is controlled by the width of the slit and the rotation speed of the shield when the slit passes. In addition, the time during which the shield 11 makes one rotation is the drop interval. If it is desired to increase the drop interval without changing the size of one drop, the rotation of the shield 11 may be temporarily stopped when the slit 12 is not located immediately below the nozzle 1. Then, after stopping for a predetermined time, it is rotated again, and the time required for one rotation as a whole may be set so as to be a desired dropping interval.

The sample liquid dropped on the combustion tube 31 is supplied to the nozzle 1
As it falls while maintaining the flow velocity flowing out of the
It reaches the position where the catalyst 32 is supported. Then, it is heated and oxidized there to become a sample gas. At this time,
Nitrogen contained in the sample liquid becomes nitric oxide gas. This reaction can be completed in a very short time because the amount of one drop can be made extremely small, and does not exceed the combustion capacity of the combustion tube 31 even if it is dropped one after another at short intervals.

The on-off valve 55 is always open during the analysis operation, and the sample gas generated by the carrier gas is passed through the dehumidifier 44 and the buffer 46 to the chemiluminescence cell 4.
5 is introduced. At this time, nitric oxide in the sample gas is dispersed in the carrier gas by the buffer 46.

In the chemiluminescent cell 45, the nitric oxide in the sample gas reacts with the ozone gas to generate chemiluminescence. By detecting this, the nitrogen contained in the sample solution can be analyzed. The chemiluminescence signal is obtained by dropping the sample solution at intervals shorter than the time during which the chemiluminescence signal obtained from one drop of the sample solution continues.
Signals resulting from multiple droplets overlap. And, combined with the operation of the buffer 46, a continuous signal with little ripple can be obtained. Therefore, the signal can be immediately converted to the nitrogen amount without integrating the signal.

To perform the standard solution calibration, the three-way valve 3 is switched to the standard solution supply pipe 5 side. Since the switched standard solution is continuously sent to the nozzle 1, the output of the chemiluminescent cell 45 when the standard solution is measured can be quickly obtained. Therefore, the calibration work can be performed in a short time.

Next, the configuration of a total nitrogen analyzer according to another embodiment of the present invention will be described with reference to FIG.
2, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In the analyzer according to the present embodiment, the shield 11 in the analyzer of FIG. 1 is arranged to be inclined with respect to the horizontal plane. At the same time, peripheral members such as the motor 14 and the housing 21 are also inclined. In the present embodiment, since the shield 11 is inclined so as to descend as the distance from the nozzle 1 increases, the shielded sample liquid flows in a direction away from the nozzle 1. Therefore, the danger that the sample liquid that should have been shielded falls directly below the nozzle 1 can be further reduced. Further, since the housing 21 is also inclined, the sample liquid dropped on the bottom surface is quickly discharged to the drain pipe 22.

Next, the configuration of a total nitrogen analyzer according to another embodiment of the present invention will be described with reference to FIG.
3, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In the analyzer according to the present embodiment, the shield 11 in the analyzer of FIG. As shown in the figure, the shielding body 61 has a substantially frustoconical shape with an open lower part, and has a slit 62 on a side surface thereof. In the present embodiment, since the side surface of the shield 61 is inclined so as to be lowered as it moves away from the rotation axis 13, the shielded sample liquid is quickly moved to the outside of the shield 61 together with the centrifugal force accompanying the rotation. To be eliminated. Therefore, also in the present embodiment, the danger of the sample liquid that should have been shielded from dropping directly below the nozzle 1 can be further reduced.

Next, the configuration of a total nitrogen analyzer according to another embodiment of the present invention will be described with reference to FIG.
4, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In the analyzer according to the present embodiment, the shield 11 in the analyzer of FIG. 1 is changed to a shield composed of shield units 71 and 72. The gap 73 between the shielding units 71 and 72 is kept constant by a connecting member 74 as shown in the figure. Then, instead of the motor 14, the connecting member 74 is reciprocated using a drive source (not shown) for performing a linear reciprocating motion.
The shielding units 71 and 72 are reciprocated while maintaining the gap 73. In addition, independent of this reciprocating motion, a rotation unit (not shown) for rotating the shielding units 71 and 72 is provided. In the present embodiment, since the shielded sample liquid is quickly separated from immediately below the nozzle 1 by rotation, even if the slit 73 reciprocates, the once shielded sample liquid does not drop directly below the nozzle due to inertial force.

Next, the configuration of a total nitrogen analyzer according to another embodiment of the present invention will be described with reference to FIG.
5, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In the analyzer according to the present embodiment, the shield 11 in the analyzer of FIG. 1 is changed to a shield composed of shield units 81 and 82. The gap 83 between the shielding units 81 and 82 is kept constant by a connecting member 84 as shown in the figure. Then, instead of the motor 14, the connecting member 84 is reciprocated using a drive source (not shown) for performing a linear reciprocating motion.
The shielding units 81 and 82 are reciprocated while maintaining the gap 83. In addition, the shielding unit 8
1 and 82 are inclined so as to decrease as they move away from the nozzle 1, so that the shielded sample liquid
Flows away from Therefore, even in the case of reciprocating motion, there is little danger that the shielded sample liquid falls directly below the nozzle 1.

Next, the configuration of a total nitrogen analyzer according to another embodiment of the present invention will be described with reference to FIG.
6, the same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In the analyzer according to the present embodiment, the shield 11 in the analyzer of FIG. As shown in the figure, the shield 91 has a curved plate shape with a recessed lower portion, and has a slit 92 at substantially the center thereof.

In this embodiment, the time during which the slit 91 is located immediately below the tip of the nozzle 1 is limited by moving the nozzle 1 instead of driving the shield side. Here, the nozzle 1 does not move the whole, but moves only the tip part like a pendulum. Therefore, it is not necessary to move the connected pipes while dragging them. Further, in the present embodiment, since the upper surface of the shield 91 is inclined so as to lower as the distance from the slit 92 increases, the shielded sample liquid is quickly removed to the outside of the shield 91. Therefore, also in the present embodiment, the danger of the sample liquid that should have been shielded from dropping directly below the nozzle 1 can be further reduced.

In the embodiment described with reference to FIGS. 3 to 6, it is needless to say that a wiper can be appropriately used. Also, the bottom surface of the housing 21 can be made to have an appropriate height difference by being inclined, for example, as shown in FIG.

The housing 21 is preferably provided for facilitating the introduction of the carrier gas, but is not essential. If this is omitted, a branch pipe is attached to the inlet pipe 34 of the combustion pipe 31 and the carrier gas flow path 53 is directly connected thereto, and the introduced carrier gas does not flow out from the upper part of the inlet pipe 31. A configuration such as providing such a backflow prevention means is required.

In the above embodiments, the analyzer is configured as a total nitrogen analyzer using the chemiluminescent cell 45. However, as described above, by changing the configuration of the analyzer 42, various analyzers for burning and measuring the sample liquid can be used. Can be configured as For example, if you provide an infrared gas analyzer that can measure carbon dioxide,
Since the carbon in the sample liquid is burned into carbon dioxide, it can be used as a total organic carbon analyzer. In addition, if an oxygen gas analyzer such as a zirconia battery for measuring oxygen is provided, the amount of oxygen consumed during combustion can be obtained, so that a total oxygen demand analyzer for a sample liquid can be obtained.

[0070]

EXAMPLE As an example, a total nitrogen analyzer in which the shield 11 in FIG. 1 is arranged so as to be inclined with respect to the horizontal plane as shown in FIG. 2 will be described. In the present embodiment, the nozzle 1 having an inner diameter of 0.16 mm and a length of 10 mm has a diameter of 3.6 m.
The sample liquid was continuously flowed at L / min. As the sample liquid, 0
A standard solution of an aqueous potassium nitrate solution of mg / L to 100 mg / L was used. The sample liquid supply pipe 4 from the three-way valve 3 to the nozzle 1 had an inner diameter of 0.5 mm and a length of 200 mm. Then, the nozzle 1 was arranged above the position 5 mm from the rotation axis of the shield 11 made of a disk having a diameter of 65 mm. The width of the slit 12 was 1 mm. Rotating body 11
Repeatedly rotated for 3 seconds and then stopped for 5 seconds so as to rotate once every 8 seconds. In addition,
The rotation and the stop are timings when the slit 12 stops at a position not directly below the nozzle 1.

From the liquid dropping device thus constructed, about 2.5 μL of sample liquid could be dropped at a rate of once every 8 seconds. This one drop of sample solution is about 30
Since it is oxidized in seconds, the nitrogen monoxide gas mixed into the carrier gas overlaps one after another and is substantially homogenized in the buffer 46. The capacity of the buffer 46 is 100 mL.
And As a result, as shown in FIG. 7, almost constant data corresponding to the concentration of the sample solution could be directly and continuously obtained. Therefore, the total nitrogen amount could be immediately obtained from the indicated value.

In the apparatus of the present embodiment, when the three-way valve 3 was switched to introduce sample liquids having different concentrations, the magnitude of the signal obtained from the chemiluminescent cell 45 changed about 3 minutes after the switching.

[0073]

According to the present invention, it is possible to provide a liquid dropping device which can supply a sample liquid as a very small amount of liquid droplets, can replace liquid quickly, and can be manufactured at a low cost with a simple structure. In addition, it is possible to provide an oxidation reaction apparatus which can oxidize a sample solution in a short time, can quickly respond to replacement of the sample solution, and can be manufactured at a low cost with a simple configuration. In addition, an analyzer that can continuously obtain measurement data of sample liquids, has good replacement of sample liquids, can be manufactured at low cost without complicated data processing mechanisms and mechanical configurations, and can measure accurately. Can be provided. According to the present invention, it is possible to provide an apparatus having extremely high practicality for continuous analysis of total nitrogen, total organic carbon, and total oxygen demand.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a total nitrogen analyzer according to an embodiment of the present invention, in which (a) is a configuration diagram in which a part is shown in a vertical cross-sectional view, and (b) is a cross-sectional view in which the vicinity of a shield is viewed from above. .

FIG. 2 is a side view near a shield of a total nitrogen analyzer according to another embodiment of the present invention.

FIG. 3 is a perspective view near a shield of a total nitrogen analyzer according to another embodiment of the present invention.

4A and 4B show the vicinity of a shield of a total nitrogen analyzer according to another embodiment of the present invention, wherein FIG. 4A is a front view and FIG. 4B is a plan view.

5A and 5B show the vicinity of a shield of a total nitrogen analyzer according to another embodiment of the present invention, wherein FIG. 5A is a front view and FIG. 5B is a plan view.

6A and 6B show the vicinity of a shield of a total nitrogen analyzer according to another embodiment of the present invention, wherein FIG. 6A is a front view and FIG. 6B is a plan view.

FIG. 7 is data obtained by a total nitrogen analyzer according to an example of the present invention.

FIG. 8 is a configuration diagram of a total nitrogen analyzer according to the related art.

FIG. 9 is a configuration diagram of a piezo pump.

FIG. 10 is data obtained by a total nitrogen analyzer according to the related art.

[Explanation of symbols]

 Reference Signs List 1 nozzle 2 liquid supply pipe 11 shield 12 slit 14 motor 17 wiper 21 housing 31 combustion pipe 32 catalyst 38 electric furnace 45 chemiluminescence cell 53 carrier gas flow path

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G01N 33/18 103 G01N 35/08 A 35/08 35/06 D (72) Inventor Megumi Ichioka Musashino, Tokyo 4-13-14, Kichijoji-Kitacho, Ichichi-shi Electrochemical Instruments Co., Ltd. (72) Inventor Setuko Kamata 4-13-14, Kichijoji-Kitacho, Musashino-shi, Tokyo F-term in Electrochemical Instruments Co., Ltd. 2G042 AA01 BA01 BA05 BA07 CA02 CB03 DA04 HA02 2G058 AA01 AA03 BA01 BB02 EA11 EA14 EC07 ED01 FB27 GA06 GD02

Claims (22)

[Claims] 1. A nozzle from which a sample liquid flows out, a liquid feeding means for continuously supplying the sample liquid to the nozzle, and a shield provided below the nozzle and having a region through which the sample liquid can partially pass. A driving unit for driving the shield, wherein the driving of the shield by the driving unit limits a time during which a region in the shield that can pass the sample liquid is located immediately below the tip of the nozzle. Dropping device. 2. The liquid dropping device according to claim 1, wherein the region of the shield through which the sample liquid can pass is formed by a gap between two shielding units in which a gap between them is kept constant. 3. The shield according to claim 1, wherein the region through which the sample liquid can pass is slit-shaped, and the driving means drives the shield in a direction perpendicular or substantially perpendicular to the slit. Or the dropping device according to claim 2. 4. The liquid dropping device according to claim 1, wherein the driving means rotates the shield in one direction. 5. The liquid dropping device according to claim 1, wherein the driving means rotates the shield intermittently in one direction. 6. The droplet dropping device according to claim 2, wherein the driving means reciprocates the shielding body on a straight line and includes a rotating means for rotating each of the two shielding units. 7. The liquid dropping device according to claim 1, wherein an upper surface of the shield is inclined with respect to a horizontal plane. 8. The liquid dropping device according to claim 1, further comprising a wiper for removing a sample liquid adhering to the surface of the shield other than immediately below the tip of the nozzle. . 9. A nozzle from which a sample liquid flows out, a liquid feeding means for continuously supplying the sample liquid to the nozzle, and a shield which is located below the nozzle and has a region where the sample liquid can partially pass therethrough. Driving means for driving the tip of the nozzle, wherein the drive of the tip of the nozzle by the driving means limits the time during which the area in the shield body through which the sample liquid can pass is located immediately below the tip of the nozzle. Dropping device. 10. The shield according to claim 1, wherein the area through which the sample liquid can pass is slit-shaped, and the driving means drives the tip of the nozzle in a direction perpendicular or substantially perpendicular to the slit of the shield. 10. The liquid dropping device according to item 9. 11. The liquid dropping device according to claim 9, wherein an upper surface of the shield is inclined with respect to a horizontal plane. 12. A combustion tube having an inlet and an outlet, droplet supply means for supplying sample liquid droplets to the entrance of the combustion tube, carrier gas supply means for supplying carrier gas to the entrance of the combustion tube, An oxidation reactor, comprising: heating means for heating the combustion tube; and the droplet supply means being the droplet dropping device according to any one of claims 1 to 11. 13. The carrier gas supply means includes a housing and a gas inflow pipe through which a carrier gas flows into the housing. The housing accommodates a shield of the liquid dropping device in an airtight manner. In addition, the tip of the nozzle of the droplet dropping device and the inlet side of the combustion tube are hermetically inserted, and a water-sealed outlet for discharging the sample liquid removed by the shield is provided. Claim 1
3. The oxidation reactor according to 2. 14. A combustion tube having an inlet and an outlet, droplet supply means for supplying sample liquid droplets to the entrance of the combustion tube, carrier gas supply means for supplying carrier gas to the entrance of the combustion tube, 12. The droplet supply means according to claim 1, further comprising: a heating unit for heating the combustion tube; and an analysis unit configured to generate a measurement signal by introducing a gas flowing out from an outlet side of the combustion tube. An analyzer characterized by being a droplet dropping device. 15. A combustion tube having an inlet and an outlet, droplet supply means for supplying a droplet of a sample liquid to the entrance of the combustion tube, carrier gas supply means for supplying a carrier gas to the entrance of the combustion tube, A heating unit that heats the combustion tube, and an analysis unit that generates a measurement signal by introducing a gas flowing out from the outlet side of the combustion tube, and the measurement signal obtained due to one droplet of the sample liquid is continued. An analyzer for continuously supplying droplets by said droplet supply means at intervals shorter than the time required for the analysis. 16. A combustion tube having an inlet and an outlet, a droplet supply unit for supplying a droplet of a sample liquid to the entrance of the combustion tube, a carrier gas supply unit for supplying a carrier gas to the entrance of the combustion tube, Heating means for heating the combustion tube, and an analyzer for introducing a gas flowing out from the outlet of the combustion tube to generate a measurement signal, and between the outlet of the combustion tube and the analyzer, the outlet of the combustion tube An analyzer provided with a buffer in which gas flowing out of the buffer temporarily stays. 17. A combustion tube having an inlet and an outlet, droplet supply means for supplying a droplet of a sample liquid to the entrance of the combustion tube, carrier gas supply means for supplying a carrier gas to the entrance of the combustion tube, A heating unit that heats the combustion tube, and an analysis unit that generates a measurement signal by introducing a gas flowing out from the outlet side of the combustion tube, and the measurement signal obtained due to one droplet of the sample liquid is continued. The droplets are continuously supplied by the droplet supply means at intervals shorter than the time required to perform the process, and the gas flowing out from the outlet side of the combustion tube temporarily flows between the outlet of the combustion tube and the analyzer. An analyzer comprising a buffer for staying. 18. The liquid supply device according to claim 1, wherein
The analyzer according to any one of claims 15 to 17, wherein the analyzer is the droplet dropping device according to any one of the preceding claims. 19. The carrier gas supply means includes a housing and a gas inflow pipe through which a carrier gas flows into the housing. The housing accommodates a shield of the liquid dropping device in an airtight manner. In addition, the tip of the nozzle of the droplet dropping device and the inlet side of the combustion tube are hermetically inserted, and a water-sealed outlet for discharging the sample liquid removed by the shield is provided. Claim 1
An analyzer according to claim 4 or claim 18. 20. The analyzer according to claim 1, wherein the analyzer is a chemiluminescent gas analyzer that generates a measurement signal corresponding to the amount of nitric oxide, and analyzes total nitrogen in the sample liquid based on the measurement signal. The analyzer according to any one of claims 14 to 19. 21. The method according to claim 21, wherein the analyzer is an infrared gas analyzer that generates a measurement signal corresponding to the amount of carbon dioxide, and analyzes all organic carbon in the sample liquid based on the measurement signal. The analyzer according to any one of claims 14 to 19. 22. The analyzer according to claim 14, wherein the analyzer is an oxygen gas analyzer that generates a measurement signal according to the amount of oxygen, and analyzes the total oxygen demand of the sample liquid based on the measurement signal. An analyzer according to any one of claims 1 to 19.