KR20200083254A - METHOD AND APPARATUS FOR MEASURING TOTAL ORGANIC CARBON BY COMBUSTION OXIDATION USING PROPORTIONAl CONTROL SAMPLE PRECISION INJECTION METHOD AND DOUBLE COOLING GAS-LIQUID SEPARATION - Google Patents

Abstract

The present invention relates to a method and device for measuring total organic carbon by combustion oxidation. The method for measuring total organic carbon of a sample to be measured comprises: a step of removing inorganic carbon in an inorganic carbon removal tank from a sample to be measured; a step of suctioning the sample to be measured from which inorganic carbon has been removed by a syringe pump; a step of discharging a part of the sample to be measured sucked by the syringe pump; a step of injecting the sample to be measured into a pipe connected to an oxidation reaction tank; a step of discharging all the samples to be measured remaining in the syringe pump; a step of suctioning carrier gas into the syringe pump; a step of injecting the sample to be measured filled in the pipe connected to the oxidation reaction tank into the oxidation reaction tank by using the carrier gas sucked by the syringe pump; a step of generating carbon dioxide by oxidizing the sample to be measured injected into the oxidation reaction tank; a step of transferring the generated carbon dioxide to an NDIR sensor via a cooling unit by the carrier gas; and a step of measuring the amount of the carbon dioxide transferred by the NDIR sensor. By improving the sample and carrier gas injection method by the proportional control method and gas-liquid separation of water from the carrier gas by the double cooling method, the precision of carbon dioxide measurement by the NDIR sensor can be improved.

Description

METHOD AND APPARATUS OF METHOD AND APPARATUS FOR MEASURING TOTAL ORGANIC CARBON BY COMBUSTION OXIDATION USING PROPORTIONAl CONTROL SAMPLE PRECISION INJECTION METHOD AND DOUBLE COOLING GAS-LIQUID SEPARATION}

The present invention is a method of injecting a measurement target sample and a carrier gas into an oxidation reaction tank of a measuring device and transferring it to a NDIR sensor in order to increase the precision of the measurement in measuring the total organic carbon using a combustion oxidation type total organic carbon measuring device It relates to a method and apparatus for removing moisture contained in a mixed gas of carbon dioxide and carrier gas by gas-liquid separation.

Total organic carbon (TOC) is used as a contaminant indicator that can determine the degree of contamination of water quality with chemical oxygen demand (COD) and biochemical oxygen demand (BOD). Total organic carbon is a principle of direct measurement rather than indirectly measuring the degree of contamination of organic substances such as COD or BOD, and is a highly accurate pollution indicator.

The method of measuring total organic carbon includes removing inorganic carbon such as carbonate ions, oxidizing organic substances into carbon dioxide using an oxidation reaction part, and removing moisture contained in a mixed gas of oxidized carbon dioxide gas and carrier gas. It consists of a gas-liquid separation process and a process in which the mixed gas separated by gas-liquid is sent to an NDIR sensor capable of measuring carbon dioxide. That is, it consists of inorganic carbon removal-oxidation-gas-liquid separation-carbon dioxide gas measurement.

The method of removing inorganic carbon is easily removed by adding acid to the sample to lower the pH and then introducing nitrogen gas or air to disperse the acid. Methods for oxidizing organic substances are largely divided into wet oxidation and combustion oxidation. The wet oxidation method is basically a method of oxidizing an organic substance by irradiating ultraviolet rays to a sample. In order to increase the oxidizing power, a means of adding percellate, increasing temperature, or introducing ozone is used as an auxiliary. The combustion oxidation method is a method of oxidizing organic substances at a high temperature of 650 to 950°C. Wet oxidation is suitable for analysis of samples with low concentrations or low suspended solids, but it is difficult to apply to high-concentration and non-degradable samples. In the case of combustion oxidation, there is a disadvantage that maintenance is somewhat difficult, but it is generally used to properly select and use it according to the properties of the sample and the purpose of measurement, since it is advantageous for oxidizing high concentration or non-degradable organic substances.

During the oxidation process, nitrogen or air is injected into the carrier gas. The oxidized carbon dioxide gas is discharged from the oxidation reaction tank together with the carrier gas. This mixed gas is sent to an NDIR sensor capable of quantifying carbon dioxide gas, and the concentration of carbon dioxide is measured by the NDIR sensor to be converted into total organic carbon.

The mixed gas discharged from the oxidation reactor contains a large amount of moisture. When such moisture flows into the NDIR sensor, there is no problem at first, but if it is continuously measured, the inside of the NDIR sensor will corrode, causing errors in the measurement data, and if a large amount of moisture flows into the NDIR sensor, it will cause the sensor to malfunction. Therefore, it is necessary to remove as much moisture as possible from the mixed gas discharged from the oxidation reactor and send it to the NDIR sensor.

The total organic carbon measuring device of the combustion oxidation method generally oxidizes a sample using an oxidation reactor (oxidation furnace, oxidation furnace). This is a type in which a reaction tube having a closed structure is installed inside the oxidation reactor to pass a sample and a carrier gas.

The voltage signal of the NDIR sensor increases according to the concentration and injection amount of the sample injected into the oxidation reactor, and it is converted into the total organic carbon concentration. In the case of the combustion oxidation method, it is recommended to minimize the injection amount since a liquid sample at room temperature is injected into the high-temperature combustion furnace. Generally, the injection amount is about 0.02~2mL, but in the case of wastewater, it is common to inject a sample of 0.5mL or less. When the sample injection amount increases, it takes a long time to return the temperature to the oxidation furnace, and it becomes difficult to obtain a reproducible oxidation rate. In addition, since the remaining oxidized and carbonized residues continue to accumulate in the oxidation furnace, it is advantageous to measure the total organic carbon of the combustion oxidation method by minimizing the injection amount. However, the smaller the amount of the sample is, the more precise the injection amount and the injection method becomes.

The present invention improves the sample injection method when measuring the total organic carbon of the combustion oxidation method, and also efficiently removes the moisture contained in the carbon dioxide-carrier gas mixture gas discharged from the oxidation reactor to measure the high precision combustion oxidation total organic carbon. And devices.

The present inventors have confirmed that the sample injection method and the removal of moisture by gas-liquid separation are one of the most important factors in order to increase the precision of the measurement while developing the combustion organic type total organic carbon measurement device.

As a result of experiments at various angles by the present inventors to find the optimal injection method, it was confirmed that the fluid flow inside the oxidation reactor 6 should be properly controlled when the sample is injected. In particular, it was confirmed that when the sample is injected while the carrier gas is being injected, the pressure is instantaneously increased due to the pressure and flow rate generated when the sample is injected, and as a result, the precision of the data is lowered. Therefore, in the present invention, the flow rate of the carrier gas during sample injection was adjusted according to the sample injection speed so that the total flow rate into the oxidation reactor 6 was maintained to increase the precision of the measurement.

In addition, in order to efficiently separate the gas-liquid, a double cooling method in which the gas discharged from the oxidation reactor 6 is first-liquid-separated by water cooling and second-liquid separation by air-cooling is secured. Although it is a water cooling method, water is not supplied from the outside, but the cooled water is circulated using the air cooling module 16. In this way, efficient cooling is possible, and the effect of compacting the device itself can be obtained. Also, the condensate separated by gas-liquid is automatically discharged, so there is no need to remove it manually.

According to the present invention, it is possible to increase the precision of the measurement of the total organic carbon of the combustion oxidation method. In addition, the dual-cooling method removes the moisture in the mixed gas with high efficiency, making maintenance easy and reducing the failure factor of the measuring device, thereby reducing the cost of maintenance and repair.

1 is a schematic diagram of a portion of a measuring device for explaining a method for injecting a sample and a carrier gas in a proportional control method of the present invention.
2 is a schematic diagram of a cooling unit which is a gas-liquid separation device of the present invention.
3 is a schematic diagram of an existing cooling unit which is a conventional gas-liquid separation device.
4 is a graph showing the voltage signal measured by the NDIR sensor according to the measurement time after the sample is injected into the oxidation reactor.
5 is a graph showing the number of NDIR voltage signals measured to confirm the performance of the cooling unit of the present invention.
6 is a graph showing NDIR voltage signal counts to check the performance of a conventional cooling unit.

Hereinafter, with reference to the accompanying drawings, the method and apparatus for measuring combustion oxidized total organic carbon using the proportional control sample precision injection method and the dual cooling gas-liquid separation of the present invention will be described in detail. The drawings introduced below are provided as examples in order to sufficiently convey the spirit of the present invention to those skilled in the art.

Therefore, the present invention is not limited to the drawings presented below, and may be embodied in other forms, and the drawings presented below may be exaggerated to clarify the spirit of the present invention. At this time, if there is no other definition in the technical terms and scientific terms to be used has the meaning commonly understood by those of ordinary skill in the art to which this invention belongs, and the subject matter of the present invention is unnecessary in the following description and accompanying drawings Descriptions of well-known functions and configurations that may be blurred will be omitted.

First, when the injection of the sample to be measured is described, the injection of the sample injects a small amount of the sample, so the syringe pump 2 is generally used. In addition, it is also common to use a multi-port valve 3 capable of switching channels to perform various roles such as sample injection, reagent injection, and waste liquid discharge with one syringe pump 2. The inventors also constructed and tested a measuring device using a syringe pump (2) and a multi-port valve (3). The multi-port valve (3) has a common port (port 0) and slave ports (ports 1 to 7), and a multi-port valve (3) has a disk inside to rotate the disk so that the common port 0 and each slave port If you connect it, the flow path is connected.

The method of injecting the sample to be measured first devised by the present inventors is as follows. First, after connecting the common port 0 and the subordinate port 1 to form a flow path, the sample in which the inorganic carbon is removed from the inorganic carbon removal tank 1 is sucked by the syringe pump 2. Then, connect the common port 0 and the subordinate port 6, and consider the pipe length from the syringe pump (2) to the oxidation reaction tank (6), so that the sample to be measured is injected into the oxidation reaction tank (6) by 0.1 to 0.2 mL. Infuse. In this way, the sample is filled up to the end of the injector tip installed in the oxidation reactor 6. After the oxidation reaction tank 6 is stabilized in the same manner as above, the syringe pump 2 is operated to inject 0.1 to 0.5 mL of the sample into the oxidation reaction tank 6. At this time, the voltage change over time is graphed using the voltage data of the obtained NDIR sensor, and the peak area of the graph is calculated. The area of this graph can be converted to the amount of total organic carbon, and after the calibration curve is drawn, it can be converted to the total organic carbon concentration. However, when the measurement was repeated 10 times in the same manner as above, the coefficient of variation (CV%) of the peak area data was calculated, confirming that the precision was low.

As a result of examining various factors to increase the precision, it can be seen that the sample to be measured filled in the injector tip mounted inside the oxidation reactor 6 after pre-injection does not remain stable inside the injector tip until the next injection. there was. Since the temperature inside the oxidation reactor was very high (above 650 degrees), it was confirmed that the sample inside the injector tip was pushed toward the syringe pump 2 and oxidized little by little.

Therefore, the developers have devised the following more complete injection method for stable injection of the sample to be measured without pre-injection. First, connect 1 subordinate port and 0 common port, and then aspirate 1 to 2 mL of sample with a syringe pump (2). Then, after connecting the 7th subordinate port and the 0th common port, 0.5 to 1 mL of sample is discharged. Again, connect the 6th subordinate port and the 0th common port to inject the desired sample injection amount in the range of 0.1 to 0.5mL. At this time, the sample to be measured is not injected into the oxidation reaction tank 6 and is filled in a pipe connecting the multi-port valve 3 and the oxidation reaction tank 6. After connecting the 7th subordinate port and the 0th common port, the remaining sample in the syringe pump (2) is discharged and discarded. Next, the common port 0 and the dependent port 5 are connected to aspirate 2.5 to 3.5 mL of carrier gas into the syringe pump 2. Then, the 6th subordinate port and the 0th common port are connected to inject carrier gas sucked into the syringe pump. Then, the sample to be measured filled in the pipe connecting the multi-port valve and the oxidation reactor is neatly injected into the oxidation reactor (6).

When the sample to be measured is injected as described above, the sample does not remain inside the pipe or the multiport valve 3 and is precisely injected into the oxidation reactor 6.

However, by adopting the improved precision injection method of the above-described sample to be measured, the reproducibility of the oxidation peak of the NDIR sensor was improved compared to the method before the improvement, but it was confirmed that it was still not satisfactory, so that the cause was variously investigated. As the study was conducted, one of the studies was to immerse and observe the gas piping discharged from the oxidation reactor in the water of the water tank. That is, as a result of observing by immersing the pipe about 20 centimeters from the water level, it was confirmed that an important fact was observed, and it was confirmed that strong bubbles were generated at the moment of injecting the sample while the bubbles were constantly generated according to the injection of the carrier gas. It was confirmed that this instantaneous change in pressure and flow caused a problem in measuring the NDIR sensor signal.

In order to solve this problem, it was confirmed that the reproducibility of the measurement can be increased by maintaining a constant flow rate from the oxidation reactor 6 to the cooling unit 7 through the oxidation reactor 6 while conducting continuous studies at various angles. .

That is, as a result of proportional control so that the'flow rate of carrier gas before sample injection' and'the flow rate of carrier gas flow rate after sample injection and the flow rate due to the injected sample' are always kept constant, the precision of the measurement signal of the NDIR sensor increases. Was confirmed.

In addition, as described above, since the carrier gas contains a large amount of moisture, it is difficult to measure the NDIR sensor as the number of measurements increases. The simplest and easiest method is that when the carrier gas having a high moisture content continuously flows into the NDIR sensor, the baseline of the voltage signal of the NDIR sensor rises. When the baseline of the voltage signal continues to rise, the reproducibility of the voltage signal is increased. Will be lowered.

In the present invention, this was solved by using a dual cooling method to remove all of the moisture contained in the carrier gas by gas-liquid separation. 2 is a schematic diagram of such a dual cooling cooling unit (7). The carrier gas discharged from the oxidation reaction tank 6 flows into the water cooling module 10. The water cooling module 10 is a glass material, and a water cooling coil tube 11 of a glass material is mounted therein. In the upper left and lower sides of the water cooling module 10, there is a connector through which water can be injected and withdrawn. The water cooling coil pipe 11 is cooled while circulating cold water through this connector. The gas discharged from the oxidation reaction tank 6 and flowing through the water cooling coil pipe inlet 9 is cooled and condensed while passing through the water cooling coil pipe 11. Again, the carrier gas flows into the air cooling module 16. The air cooling module is a Y tube 14 and a U tube 17 mounted as shown in FIG. 2 inside the aluminum block to which the thermoelectric element cooling module 13 is attached. The aluminum block and the Y pipe 14 and the U pipe 17 are in close contact, so that the cold air of the aluminum block is well transmitted. As the condensate and carrier gas flowing into the Y pipe 14 are separated, the condensed water goes down to the bottom of the Y pipe 14 and the carrier gas rises above the Y pipe 14 and gas-liquid separation is performed. The water collected under the Y pipe 14 does not accumulate inside the air cooling module 16 because the pump 15 is driven and discharged when the measuring device is being cleaned.

From the U pipe 17 to the pipe between the water cooling module 10 and the inside, all of the water is filled. The water cooled in the air cooling module 16 is injected into the water cooling module 10 to cool the water cooling coil pipe 11. The water with the increased temperature is cooled again while being returned to the air cooling module 16.

As described above, the carrier gas and carbon dioxide transferred from the oxidation reaction tank 6 are first cooled in the water cooling module and secondly cooled in the air cooling module 16, and then gas-liquid is separated, so that moisture can be stably removed.

When explaining the present invention by way of example for the sample injection method is as follows. 2 mL of the water quality sample from which the inorganic carbon has been removed from the inorganic carbon removal tank 1 is sucked into the syringe pump 2. After connecting 0th common port and 7th subordinate port, discharge 1mL of sample filled in syringe. Again, connect 6 subordinate ports and 0 common ports, and inject 0.4 mL of the sample to be measured into the pipe connecting the multiport valve and the oxidation reactor. After connecting the No. 7 sub-port and the No. 0 common port, discharge all the remaining sample in the syringe pump (2) and discard it. Connect the common port 0 and the dependent port 5 to suck 3 mL of carrier gas into the syringe pump (2). Thereafter, the target sample filled in the pipe connecting the multi-port valve and the oxidation reactor is injected into the oxidation reactor by using the carrier gas drawn into the syringe pump by connecting the 6th subordinate port and the 0th common port. At this time, proportional control is performed so that the total flow rate of the gas flowing into the oxidation reactor 6 is always constant. When the sample is injected for 20 seconds, the flow rate generated by the sample injection is 9 mL/minute. When the flow rate of the carrier gas is 150 mL before the sample is injected, the sample is injected with the carrier gas flow rate at 141 ml/min. In this way, the total flow rate of the injected sample and the carrier gas after the sample injection is 150 mL/min, which is maintained the same as before the sample injection. After the sample injection, the carrier gas flow rate is returned to 150 mL/min.

KHP was dissolved in ultrapure water to prepare a total organic carbon standard solution having concentrations of 1 mg/L, 10 mg/L, and 20 mg/L to prepare three measurement samples. The measurement sample was removed from the inorganic carbon removal tank. Aspirate 2 mL of the standard solution from which inorganic carbon has been removed is aspirated with a syringe pump (2). After connecting 0th common port and 7th subordinate port, discharge 1mL of sample filled in syringe. Again, connect the 6th subordinate port and the 0th common port and inject 0.4mL. After connecting the 7th subordinate port and the 0th common port, the remaining sample in the syringe pump (2) is discharged and discarded. Connect the common port 0 and the dependent port 5 to suck 3 mL of carrier gas into the syringe pump (2). After that, the carrier gas is injected by connecting the 6th subordinate port and the 0th common port.

At this time, proportional control is performed so that the total flow rate of the gas flowing into the oxidation reactor 6 is always constant. When the sample is injected for 20 seconds, the flow rate generated by the sample injection is 9 mL/minute. When the flow rate of the carrier gas is 150 mL before the sample injection, when the sample is injected, the flow rate of the carrier gas is 141 ml/min, and the sample is injected for 20 seconds to generate a flow rate of 9 mL/min through the sample injection. In this way, the flow rate generated by the sample injected after the sample injection and the total flow rate of the carrier gas are 150 mL/min, which is maintained the same as before the sample injection.

The area of the peak is obtained by measuring the voltage signal of the NDIR sensor over time. The injection flow rate of the carrier gas was tested 10 times while adjusting to 100 mL/min, 150 mL/min, 200 mL/min, 250 mL/min, and 300 mL/min. As a result, the standard deviation of the peak area was very excellent at 0.8% or less. Table 1 shows the experimental results. The temperature of the oxidation reactor was 680 degrees, and the dual cooling device of the present invention was installed to remove moisture. Table 1 shows the results.

A total organic carbon standard solution having a concentration of 20 mg/L was prepared by dissolving KHP in ultrapure water, and used as a measurement sample. Total organic carbon was continuously measured. When the total organic carbon was measured, the voltage value of the NDIR sensor increased and then decreased after sample injection, and it was assumed that the voltage value of the baseline was maintained. While continuously measuring the total organic carbon, the voltage value of the baseline was measured for each measurement to observe the change according to the number of measurements.

4 is a graph showing the variation of the voltage signal of the NDIR sensor over time after the sample is injected into the oxidation reactor 6. In this graph, the voltage of the NDIR sensor was kept stable 10 minutes after sample injection, and this was assumed as the baseline voltage. The results are shown in FIG. 5. As a result of observing the variation of the baseline according to the total number of organic carbon measurements, the variation width of the baseline did not exceed 0.088 to 0.092V until 500 measurements, and it was confirmed that moisture was well removed from the dual cooling apparatus of the present invention. .

[Comparative Example 1]

When the sample was injected, it was tested in the same manner as in Example 1, except that the sample was injected while injecting the same flow rate as before the sample injection without proportional control of the carrier gas flow rate. As a result, the coefficient of variation (CV%) was high and the precision was low compared to Example 1. Especially, when the concentration of the sample was low or the flow rate of the carrier gas was low, the precision was lower. Table 2 shows the results.

[Comparative Example 2]

When the sample was injected, the carrier gas flow rate was proportionally controlled, but it was tested in the same manner as in Example 1, except that the carrier gas was flowed by reducing the flow rate by twice the sample injection rate. As a result, the coefficient of variation (CV%) was high and the precision was low compared to Example 1. Especially, when the concentration of the sample was low or the flow rate of the carrier gas was low, the precision was lower. In particular, the precision was lower than that of Comparative Example 1. Table 3 shows the results.

[Comparative Example 3]

Experiments were carried out in the same manner as in Example 2, except that the conventional cooling apparatus shown in FIG. 3 was used. Initially, the baseline of the NDIR sensor voltage did not change significantly, but the baseline started to rise from 140 measurements and the baseline increased by about 0.3 V or more from 200 times. In the case of a normal cooling device, it was confirmed that the moisture was easily removed at the beginning of use, but the water removal performance decreased as the number of uses increased. Fig. 6 shows this result.

As described above, the present invention has been described based on the embodiments, but the spirit of the present invention should not be limited to the described embodiments, and not only the claims to be described later, but also all equivalent or equivalent modifications to the claims It will be said to fall within the scope of the inventive idea.

1 Inorganic carbon removal tank 2 Syringe pump
3 Multi-port valve 4 Flow regulator (MFC)
5 Carrier gas supply device 6 Oxidation reactor
7 Cooling unit 8 NDIR sensor
9 Water cooling coil pipe Inlet 10 Water cooling module
11 Water cooling coil tube 12 Water cooling coil tube Outlet
13 Thermoelectric element cooling module 14 Y tube
15 Discharge Pump 16 Air Cooling Module
17 U tube 18 Circulation pump
19 Existing cooling unit

Claims (12)

The method of measuring the total organic carbon of the sample to be measured is
1) removing the inorganic carbon from the inorganic carbon removal tank from the sample to be measured;
2) aspirating the measurement target sample from which the inorganic carbon has been removed into a syringe pump;
3) discharging a portion of the sample to be measured that is sucked into the syringe pump;
4) injecting the sample to be measured into the pipe connected to the oxidation reactor;
5) discharging all remaining measurement target samples in the syringe pump;
6) sucking the carrier gas into the syringe pump;
7) using a carrier gas drawn into a syringe pump, injecting a sample to be measured filled in a pipe connected to an oxidation reactor into an oxidation reactor;
8) oxidizing the measurement target sample injected into the oxidation reactor to generate carbon dioxide;
9) The generated carbon dioxide is transferred to the NDIR sensor via a cooling unit by a carrier gas; And
10) Measuring the amount of carbon dioxide transferred by the NDIR sensor; Combustion oxidation total organic carbon measuring method comprising a. According to claim 1, The total organic carbon measurement method of the sample to be measured,
1) removing the inorganic carbon from the inorganic carbon removal tank from the sample to be measured;
2) aspirating the sample to be measured from which the inorganic carbon has been removed into a syringe pump using a multiport valve;
3) discharging a portion of the sample to be measured, which is charged in the syringe pump, using a multiport valve;
4) injecting the sample to be measured into the pipe connecting the multi-port valve and the oxidation reactor;
5) discharging all the measurement target sample remaining in the syringe pump to the discharge pipe using a multiport valve;
6) suctioning the carrier gas to the syringe pump using a multi-port valve;
7) using a carrier gas sucked into a syringe pump, injecting a measurement target sample filled in a pipe connecting between the multi-port valve and the oxidation reactor into the oxidation reactor;
8) oxidizing the measurement target sample injected into the oxidation reactor to generate carbon dioxide;
9) the generated carbon dioxide is transferred to the NDIR sensor via a cooling unit by a carrier gas; And
10) measuring the voltage signal generated by the NDIR sensor according to the amount of carbon dioxide transferred to obtain an area of a peak; a method for measuring total organic carbon combustion. According to claim 2, The total organic carbon measurement method of the sample to be measured,
1) removing the inorganic carbon from the inorganic carbon removal tank from the sample to be measured;
2) connecting the subordinate port 1 connected to the inorganic carbon removal tank and the common port 0 connected to the syringe pump using a multi-port valve, and then suctioning the sample to be measured with the inorganic carbon removed into the syringe pump;
3) connecting the common port 0 connected to the syringe pump and the 7 dependent port connected to the discharge pipe using a multi-port valve, and then discharging a portion of the sample to be measured filled in the syringe pump to the discharge pipe;
4) connecting the common port 0 connected to the syringe pump and the 6 subordinate port connected to the oxidation reactor using a multiport valve, and then injecting a sample to be measured into the pipe connecting the multiport valve and the oxidation reactor;
5) After connecting the common port 0 connected to the syringe pump and the 7 dependent port connected to the discharge pipe using a multi-port valve, discharging all the samples to be measured remaining in the syringe pump to the discharge pipe;
6) connecting the common port 0 connected to the syringe pump and the slave port 5 connected to the flow controller using a multi-port valve, and then sucking the carrier gas into the syringe pump;
7) Connect the common port 0 connected to the syringe pump and the 6 dependent port connected to the oxidation reactor using a multiport valve, and then connect the multiport valve to the oxidation reactor using the carrier gas drawn into the syringe pump. Injecting a sample to be measured filled in the piping into an oxidation reactor;
8) oxidizing the measurement target sample injected into the oxidation reactor to generate carbon dioxide;
9) the generated carbon dioxide is transferred to the NDIR sensor via a cooling unit by a carrier gas; And
10) measuring the voltage signal generated by the NDIR sensor according to the amount of carbon dioxide transferred to obtain an area of a peak; a method for measuring total organic carbon combustion. According to claim 3, After the '2) connecting the 1st subordinate port connected to the inorganic carbon removal tank and the 0th common port connected to the syringe pump using a multi-port valve, the sample pump from which the inorganic carbon is removed is syringe pump. In the step of aspirating to'the sample to be aspirated is a combustion oxidation total organic carbon measuring method, characterized in that 1 to 2mL. According to claim 3, After the '3) common port 0 connected to the syringe pump and 7 subordinate ports connected to the discharge pipe are connected using a multi-port valve, a portion of the sample to be measured charged in the syringe pump is discharged. The method of measuring combustion organic carbon, characterized in that the sample to be discharged in the step of discharging to is 0.5 to 1 mL. According to claim 3, After connecting the common port No. 0 connected to the syringe pump and the subordinate port No. 6 connected to the oxidation reactor using a multiport valve, connect the sample to be measured between the multiport valve and the oxidation reactor. The method of measuring combustion oxidation total organic carbon, characterized in that the sample to be injected in the step of injecting into the connecting piping is 0.1 to 0.5 mL. According to claim 3, After the '6) connecting the common port 0 connected to the syringe pump and the 5 dependent port connected to the flow regulator using a multi-port valve, suction the carrier gas in the syringe pump' The sample to be measured is 2.5 to 3.5mL combustion oxidation total organic carbon measurement method, characterized in that. According to claim 3, After the '7) connecting the common port 0 connected to the syringe pump and the 6 subordinate port connected to the oxidation reactor using a multi-port valve, the multi-port using the carrier gas sucked in the syringe pump Combustion oxidation characterized in that the total flow rate of the gas flowing into the oxidation tank is always kept constant by proportional control in the step of injecting the sample to be measured filled in the pipe connecting the valve and the oxidation tank into the oxidation tank. How to measure total organic carbon. The method according to any one of claims 3 to 8, wherein the '9) generated carbon dioxide is transported to the NDIR sensor via a cooling unit by a carrier gas' in order to separate the liquid contained in the carrier gas from gas. Combustion oxidation total organic carbon measurement method characterized by using the double cooling method. The method of claim 9, wherein the dual cooling method is a method of condensing while passing through a water cooling module first and then passing through an air cooling module. The apparatus for measuring total organic carbon of a sample to be measured includes: an inorganic carbon removal tank for removing inorganic carbon from a sample to be measured; Syringe pump to suck or inject the sample to be measured or carrier gas from which the inorganic carbon has been removed; A discharge pipe for discharging a portion of the sample to be measured sucked into the syringe pump; An oxidation reaction tank for oxidizing the sample to be measured; Flow regulator for adjusting the flow rate of the carrier gas; A carrier gas supply device for supplying carrier gas to a flow regulator; A cooling unit cooling the carrier gas and carbon dioxide transferred from the oxidation reactor; A multi-port valve selectively connecting a syringe pump and an inorganic carbon removal tank, a discharge pipe, an oxidation reactor, or a flow regulator; And NDIR sensor; Combustion oxidation total organic carbon measuring device comprising a. 11. The method of claim 10, The cooling unit is a combustion oxidation total organic carbon measuring device, characterized in that consisting of a water cooling module and the air cooling module.

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