KR101359903B1 - Total organic carbon and total nitrogen measurement device for minimizing deviation of the measured value by air flow variation - Google Patents

Abstract

An apparatus for measuring total organic carbon and total nitrogen content which minimizes variation in measured values due to air flow fluctuations is disclosed. The total organic carbon and total nitrogen content measuring device according to the present invention includes a sample injection device 130 continuously and quantitatively injecting the measured sample water into the non-catalytic thermal combustion oxidation reactor 120, and the sample injection device 130. And a non-catalytic thermal combustion oxidation reactor (120) for oxidizing and converting all nitrogen compounds into CO ₂ and oxidizing the carbon component contained in the measurement sample by heating the sample water supplied from the sample. It is provided between the reactor 120 and the sample injection device 130 and includes a first port P1 that is a common port, a second port P2 that is in a normal closed mode, and a third port P3 that is in a normal open mode. The main solenoid valve is made of 140A, and the bottom surface consisting of a hexahedron is tightly fixed to the main solenoid valve 140A and perforated into the body from the first side and bent vertically downward to extend to the bottom The first flow path 141 connecting the sample injection device 130 side and the first port P1, and is perforated into the body at the second side and bent vertically downward to extend to the bottom surface of the carrier gas side and the second. A second flow path 142 connecting the port P2, and is bored into the body from the third side and bent vertically downward to extend to the bottom surface to open the catalyst-free thermal combustion oxidation reactor 120 and the second port (P2) Third flow path 143 to be connected, the fourth flow path for connecting the third port (P3) in the normal open mode of the solenoid valve by being drilled into the body from the fourth side and extending vertically downward to the bottom ( 144 is formed, and a portion bent vertically downward of the second flow passage 142 and the third flow passage 143 includes a distribution jig 140B formed to cross-connect with each other.
According to the present invention, the total organic carbon and total nitrogen content are minimized by removing the deviation of the measured value caused by the variation of the air flow, which is a carrier gas that is blown in the process of supplying the sample or the wash water. An apparatus is provided.

Description

Total organic carbon and total nitrogen measurement device for minimizing deviation of the measured value by air flow variation}

The present invention relates to a total organic carbon and total nitrogen measurement device, and more particularly, to a total organic carbon and total nitrogen measurement device that minimizes the measurement value fluctuation caused by air flow fluctuations.

In various fields, the total organic carbon (TOC) content or total nitrogen (TN) content in wastewater can be measured, and the measured TOC or TN content is distributed over a wide range. A typical approach for measuring the content of TOC or TN in wastewater is to oxidize the carbon compounds in the sample into carbon dioxide and the nitrogen compounds in the form of nitrogen oxides (NOx). ) Is to measure the amount. For TOC or TN content analysis of samples with relatively high purity, the sample is typically exposed to UV energy (ie, 254 nm or less) provided by a mercury lamp, usually in the presence of TiO2 or other catalysts. Let's go.

Current broad ranges of TOC or TN content analysis methods use reagents and / or catalysts, such as sodium persulfate and phosphoric acid, to oxidize organic compounds in a sample to carbon dioxide. Alkaline potassium persulfate is used to oxidize to nitrogen oxides (NOx). In addition, in order to cause oxidation, UV energy (ie, 254 nm or less) provided by a mercury lamp is generally used, or heat of generally at least about 100 ° C. The oxidation time is generally about 30 minutes and the reagents must be replenished frequently. In general, the produced carbon dioxide (CO2) or nitrogen oxides (NOx) is diffused through the membrane into the ultrapure water sample, and the conductivity of the ultrapure water sample is measured to determine the content of carbon dioxide (CO2) or nitrogen oxides (NOx). do. Again, this method increases complexity at high concentrations of carbon dioxide (CO2) or nitrogen oxides (NOx).

As mentioned, the oxidation of carbon compounds to carbon dioxide (CO2) or the oxidation of nitrogen compounds to nitrogen oxides (NOx) can be facilitated by several methods. In addition, additional changes can be made in the treatment of the sample. The sample may remain stationary in an oxidation cell, or the carbon or nitrogen compounds in the flow stream may be oxidized while flowing through the oxidation cell. In the latter case, the amount of carbon dioxide (CO2) or nitrogen oxides (NOx) produced is usually determined by measuring the conductivity at the inlet and outlet of the cell to determine the change in conductivity. However, this method can provide precise measurement of the content of TOC or TN only when the reaction is completed or to a known degree while the sample is in the cell, neither of which can be reliably guaranteed.

In a non-catalyzed oxidation process, samples are generally contained in platinum crucibles and heated to high temperatures, such as 600 ° C to 900 ° C. The produced carbon dioxide (CO2) is generally measured by an NDIR detector and the nitrogen oxides (NOx) are measured by an ECD detector.

Korean Unexamined Patent Publication No. 10-2013-0036750 discloses a total organic carbon and total nitrogen content measuring apparatus based on a non-catalytic thermal combustion oxidation method. According to the published patent, total organic carbon (hereinafter referred to as TOC) and total nitrogen (total Nitrogen: hereinafter referred to as TN) included in the measurement water are measured, for example, a constant TN value known in the calibration process or Even when TN and TOC of a calibration solution having a TOC value were measured, it was found that the measured value was not constant and a deviation occurred. The present inventor solves this problem by discovering that the cause of the deviation of the measured value is due to the fluctuation of the air flow, the carrier gas which is blown in the process of supplying the sample or the wash water.

The technical problem to be achieved by the present invention is that through the distribution jig designed to maintain a constant air flow by finding that the cause of the deviation of the measurement value is caused by the fluctuation of the air flow, the carrier gas that is blown in the process of supplying the sample or wash water It is to provide a total organic carbon and total nitrogen content measuring device that minimizes the deviation of the measured value due to air flow fluctuations by allowing the catalyst to enter the catalyst-free thermal combustion oxidation reactor.

The total organic carbon and total nitrogen content measuring device which minimizes the deviation of the measured value due to air flow fluctuations according to the present invention for achieving the above object,

A first tank 100 storing a sample to be measured for total organic carbon and total nitrogen content, and a second tank 102 storing a cleaning solution for measuring the next sample;

A pump 104 for pumping sample water and a cleaning solution in the first tank 100 and the second tank 102;

A first solenoid valve 110 and a second solenoid valve 112 installed between the first and second tanks 100 and 102 and the pump 104 to control whether a pumping liquid is supplied;

TC port 114 for buffering the sample water or the cleaning solution supplied from the pump 104;

A TIC port 122 for mixing and buffering sample water and hydrochloric acid 121 supplied from the pump 104;

A sample injection device (130) for continuously metering the measured sample water into the non-catalytic thermal combustion oxidation reactor (120);

A catalyst-free thermal combustion oxidation reactor (120) which receives the sample water from the sample injection device (130) and heats the carbon component contained in the sample to be oxidized to CO2 and oxidizes and converts all nitrogen compounds into NOx;

A first port P1 that is installed between the non-catalytic thermal combustion oxidation reactor 120 and the sample injection device 130, a second port P2 that is in a normal close mode, and a third port that is in a normal open mode. A main solenoid valve 140A including P3;

The bottom surface is made of a hexahedron and is tightly fixed to the main solenoid valve 140A, perforated into the body at the first side, and bent vertically downward to extend to the bottom so that the sample injection device 130 side and the first port P1 are extended. The first flow path 141 to connect, the second flow path 142, the third side connecting the carrier gas side and the second port (P2) by being bored into the body from the second side and extended vertically downward to the bottom The third flow path 143 connecting the non-catalytic thermal combustion oxidation reactor 120 and the second port P2 by perforating into the body and extending vertically downward to the bottom, perforating into the body from the fourth side. And vertically bent downward to extend to a bottom surface, a fourth flow path 144 connecting the drain side and the third port P3 in the normal open mode of the solenoid valve is formed, wherein the second flow path 142 and the third flow path are formed. Euro (143) Folded vertically downward portion is the distribution that is formed so as to cross each other connected to the jig (140B);

Cooling unit 150 for cooling the gas vaporized by the non-catalyst thermal combustion oxidation reactor 120;

A discharge device 152 for discharging the condensed water by cooling by the cooling unit 150;

A carrier gas pump 162 for supplying a carrier gas 160; And

It characterized in that it comprises a detector 170 for detecting the oxidized nitrogen oxides and total organic carbon contained in the gas cooled by the cooling unit 150.

In addition, the lower cap 180 of the TIC port 122,

A lower cap body 1802 having an upper opening and an air inlet 1803 on the side thereof;

A glass filter 1804 placed on the inner bottom of the lower cap body 1802 that is open; And

More preferably, the O-ring 1806 seals the sample water in the cylindrical body 1222 so as not to leak to the outside by being placed on the upper surface of the glass filter 1804.

In addition, the distribution jig is formed with the first side to the fourth side obliquely downhill inclined and perforated toward the inside of the body in the inclined surface direction so that each flow path is bent at each port (P1, P2, P3) than 90 degrees It is more preferable that it is made larger and smaller than 180 degrees.

In addition, the dispensing jig may be configured such that the upper end of the second flow path 142 and the third flow path 143 intersect each other at an angle of 90 degrees or more and less than 180 degrees or in a straight line.

According to the present invention, the total organic carbon and total nitrogen content are minimized by removing the deviation of the measured value caused by the variation of the air flow, which is a carrier gas that is blown in the process of supplying the sample or the wash water. Provide the device.

Also,

1 is a block diagram showing the structure of a total organic carbon and total nitrogen content measuring apparatus minimizes the deviation of the measured value due to air flow variation according to an embodiment of the present invention,
2 is a perspective view showing the structure of the main solenoid valve 140A installed between the catalyst-free thermal combustion oxidation reactor 120 and the sample injection device 130;
3A is a perspective view showing the structure of the dispensing jig 140B tightly fixed to the main solenoid valve 140A,
3B is a perspective view illustrating a third solenoid valve 140 formed by coupling a main solenoid valve 140A and a dispensing jig 140B.
3C is a perspective view showing another structure of the dispensing jig 140B tightly fixed to the main solenoid valve 140A,
3D and 3E are perspective views showing another structure of the dispensing jig 140B tightly fixed to the main solenoid valve 140A,
4 is a view for explaining the process of the sample is introduced into the TC port,
5 is a view for explaining a process of injecting a sample into the non-catalyst thermal combustion oxidation reactor,
6 is a view for explaining a process of measuring TC;
7 is a view for explaining the flow of air at the time of TC measurement,
8 is a view for explaining a process of injecting a sample into the TIC port,
9 is a view for explaining a process of injecting hydrochloric acid into the TIC port,
10 is a view for explaining a process of measuring a TIC,
11 is a view for explaining the flow of air in the TIC measurement,
12 is a view for explaining the flow of the cleaning solution,
13 is a perspective view showing the structure of the TIC port 122, and
14 and 15 are a perspective view and an exploded perspective view showing the structure of the lower cap 180 provided in the TIC port 122.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

FIG. 1 is a block diagram illustrating a structure of a total organic carbon and total nitrogen content measuring apparatus which minimizes variation in measured values due to air flow variation according to an exemplary embodiment of the present invention. 1, the total organic carbon and total nitrogen content measuring apparatus according to the present invention,

A first tank 100 storing a sample to be measured for total organic carbon and total nitrogen content, and a second tank 102 storing a cleaning solution for measuring the next sample,

Pump 104 for pumping the sample water and the cleaning solution in the first tank 100 and the second tank 102,

A first solenoid valve 110 and a second solenoid valve 112 installed between the first and second tanks 100 and 102 and the pump 104 to control whether a pumping liquid is supplied;

TC port 114 for buffering the sample water or the cleaning solution supplied from the pump 104,

TIC port 122 for mixing and buffering the sample water and hydrochloric acid 121 supplied from the pump 104, and

A sample injection device 130 for continuously metering the measured sample water into the non-catalytic thermal combustion oxidation reactor 120 is provided.

In addition, the said total organic carbon and total nitrogen content measuring apparatus,

A catalyst-free thermal combustion oxidation reactor (120) which receives the sample water from the sample injection device (130) and heats the carbon component contained in the measurement sample to CO2 and oxidizes and converts all nitrogen compounds into NOx;

As shown in FIG. 2, a first port P1, which is installed between the non-catalytic thermal combustion oxidation reactor 120 and the sample injection device 130, and a second port P2 that is in a normal closed mode. And a main solenoid valve 140A having a third port P3 in a normal open mode, and

As shown in Figure 3a, the bottom surface made of a hexahedron is tightly fixed to the main solenoid valve 140A and perforated into the body from the first side and bent vertically downward to extend to the bottom surface and the sample injection device 130 side A first passage 141 connecting the first port P1, a second hole which is perforated into the body at the second side and is bent vertically downward and extends to the bottom surface to connect the carrier gas side and the second port P2; Flow passage 142, the third flow passage 143 that is perforated into the body from the third side and bent vertically downward to extend to the bottom to connect the non-catalyst thermal combustion oxidation reactor 120 and the second port (P2), A fourth flow path 144 is formed to connect the drain port and the third port P3 in the normal open mode of the solenoid valve by being drilled into the body and extending vertically downward from the fourth side to the bottom surface. U 142 and the folded portion of the vertical lower portion of the third flow path 143 is provided with a dispensing fixture (140B) which is formed such that each cross-connect.

The main solenoid valve 140A and the dispensing jig 140B form the third solenoid valve 140.

The effect of the total organic carbon and total nitrogen content measuring device comprised as mentioned above is demonstrated.

In the main solenoid valve 140A, the first port P1 is a common port, the second port P2 is a normal close mode (NC) port, and the third port P3 is a normal open mode ( Normal Open: NO) port. The main solenoid valve 140A is controlled to open and close each port by an electrical signal, which is controlled by a microcomputer (not shown).

For the measurement, if the third solenoid valve 140 is controlled to open the second port P2 in the normal closed state and the third port P3 in the normal open state is closed, the sample number is passed through the first port P1 which is the common port. Since the carrier gas is always under pressure and is directed to the second port P2, the sample water is introduced into the non-catalytic thermal combustion oxidation reactor 120. If the control is maintained so that the proper pressure is maintained, it is possible to direct the sample to the non-catalyst thermal combustion oxidation reactor 120 in the state where the water cannot go out to the carrier gas inlet, and after the measurement, the third solenoid valve 140 is controlled to normal in When the second port P2 is closed and the third port P3 that is normally open is opened, the sample water is no longer directed to the non-catalytic thermal combustion oxidation reactor 120 and is drained through the third port.

At this time, the second port (P2) is a normal closed (NC) port and the portion bent vertically downward of the second flow path 142 and the third flow path 143 is formed so as to cross-connect each other, the carrier gas is non-catalyst heat combustion It should be noted that there is always flow into the oxidation reactor 120. On the other hand, while the sample water is directed to the non-catalyzed thermal combustion oxidation reactor 120, the carrier gas is blocked from entering the non-catalytic thermal combustion oxidation reactor 120 by the sample water, and thus does not affect the temperature for oxidation in the oxidation reactor. . By maintaining a constant air flow in this way it is possible to ensure that the measured value is not changed by the sudden flow of air.

Next, the gas vaporized by the non-catalytic thermal combustion oxidation reactor 120 is introduced into the cooling unit 150 and cooled, and the discharge device 152 is cooled by the cooling unit 150 to discharge the condensed water. do. The carrier gas pump 162 supplies the carrier gas 160 to facilitate the cleaning activity during the discharge and cleaning of the sample water after the measurement. The detector 170 detects oxidized nitrogen oxides and total organic carbon contained in the gas cooled by the cooling unit 150.

3C shows another structure of the dispensing jig 140B tightly fixed to the main solenoid valve 140A as a perspective view. Referring to Figure 3c, the distribution jig, the first side to the fourth side is formed obliquely downhill inclined and perforated toward the inside of the body in the inclined surface direction each flow path is bent into the respective ports (P1, P2, P3) The angle is made larger than 90 degrees and smaller than 180 degrees. This distribution jig structure can reduce the fluctuation of the air flow by reducing the angle of the passage through which the air passes, thereby further reducing the fluctuation of the measured value.

3D and 3E show another structure of the dispensing jig 140B tightly fixed to the main solenoid valve 140A as a perspective view. 3D and 3E, the dispensing jig is formed such that the upper flow paths of the second flow path 142 and the third flow path 143 intersect with each other at least 90 degrees or less than 180 degrees or in a straight line. . This distribution jig structure can reduce the fluctuation of the air flow by reducing the angle of the flow path through which the air passes, and in particular, the oxidation reactor, that is, the non-catalyst, in which the fluctuation of air has the greatest influence on the measured value. The air is more uniformly flowed into the thermal combustion oxidation reactor 120, and the fluctuation of the flow is less, thereby reducing the fluctuation factor of the air flow that may occur for a very short time in a long time measurement.

4 shows a process in which the sample is introduced into the TC port. Referring to FIG. 4, after the first solenoid valve 110 is opened and the pump 104 is operated to transfer the sample to the TC port 114 and discharge the sample, the sample is introduced. Next, as illustrated in FIG. 5, a sample is injected into the non-catalytic thermal combustion oxidation reactor 120, and TC is measured as illustrated in FIG. 6. The CO 2 gas oxidized in the non-catalytic thermal combustion oxidation reactor 120 is detected by the detection unit 170 via the cooling unit 150.

7 is a view for explaining the flow of air at the time of TC measurement. Referring to FIG. 7, the sample is injected according to the on / off of the fourth solenoid valve. However, as described above with reference to FIGS. 2 to 4, the carrier gas 160 is supplied by the carrier gas pump 162. By maintaining a constant air flow to the catalytic thermal combustion oxidation reactor 120 and abrupt change in the air flow is reduced to reduce the temperature change in the heating device to reduce the measurement deviation.

Meanwhile, in the process of injecting the sample into the TIC port 122 as shown in FIG. 8, it is independent of the third solenoid valve 140, and thus there is no other effect. As illustrated in FIG. 9, hydrochloric acid is added to the TIC port 122. Injected (121). As shown in FIG. 10, TIC is measured while hydrochloric acid is injected. Air flow in the TIC measurement is as shown in FIG. Next, the water condensed in the cooling unit 150 and the solution overflowed from the TC port 114 is discharged.

In order to remove the influence of the previous sample when measuring the next sample, the control is made to flow the cleaning solution as shown in FIG. Referring to FIG. 12, the cleaning solution 102 is pumped by the pump 104 to flow into the TC port 114 and the carrier gas 160 is supplied by the carrier gas pump 162 while the catalyst-free thermal combustion oxidation reactor is performed. The cleaning of the entire apparatus is done via 120.

13 shows the structure of the TIC port 122 in a perspective view. Referring to FIG. 13, a sample is injected into the upper end of the upper cap 1220, and a first outlet 1224 through which the oxidized gas is ejected and a second outlet 1226 through which the sample water overflows from the cylindrical body 1222. , Hydrochloric acid inlet 1228 is provided, the lower cap is provided with an air inlet through which air is introduced to mix the sample water and hydrochloric acid. However, in the process of evenly dispersing the hydrochloric acid in the sample in the TIC port 122 and oxidizing the air, the sample water and the hydrochloric acid may not be evenly mixed to cause variation in the measurement data. In order to solve this problem, as shown in FIGS. 14 and 15, the lower cap 180 has an upper cap and a lower cap body 1802 having an air inlet 1803 on its side, and placed on an open inner bottom. A glass filter 1804 to be released and an O-ring 1806 for sealing the sample water in the cylindrical body 1222 so as not to leak to the outside by being placed on the upper surface of the glass filter 1804.

In the structure as described above, the air introduced through the air inlet 1803 passes through a plurality of filter meshes provided in the glass filter 1804, and the pressure is evenly dispersed, so that the injected hydrochloric acid is more stably mixed with the sample water. The fluctuation will be reduced. Here, it is worth noting that the glass filter 1804 does not act as a filter, and that the material is made of glass, so that the glass filter 1804 does not tear due to pressure and is excellent in durability.

100: first tank 102: second tank
104: pump
110: first solenoid valve 112: second solenoid valve
114: TC port 122: TIC port
130: sample injection device
120: non-catalytic thermal combustion oxidation reactor
P1: first port P2: second port
P3: Third port
140A: Main Solenoid Valve 140B: Distribution Jig
140: third solenoid valve
141: first flow path 142: second flow path
143: third euro 144: fourth euro
150: cooling unit 152: discharge device
160: carrier gas 162: carrier gas pump
170: detector

Claims (4)

A first tank 100 storing a sample to be measured for total organic carbon and total nitrogen content, and a second tank 102 storing a cleaning solution for measuring the next sample;
A pump 104 for pumping sample water and a cleaning solution in the first tank 100 and the second tank 102;
A first solenoid valve 110 and a second solenoid valve 112 installed between the first and second tanks 100 and 102 and the pump 104 to control whether a pumping liquid is supplied;
TC port 114 for buffering the sample water or the cleaning solution supplied from the pump 104;
A TIC port 122 for mixing and buffering sample water and hydrochloric acid 121 supplied from the pump 104;
A sample injection device (130) for continuously metering the measured sample water into the non-catalytic thermal combustion oxidation reactor (120);
A catalyst-free thermal combustion oxidation reactor (120) which receives the sample water from the sample injection device (130) and heats the carbon component contained in the sample to be oxidized to CO2 and oxidizes and converts all nitrogen compounds into NOx;
A first port P1 that is installed between the non-catalytic thermal combustion oxidation reactor 120 and the sample injection device 130, a second port P2 that is in a normal close mode, and a third port that is in a normal open mode. A main solenoid valve 140A including P3; And
The bottom surface is made of a hexahedron and is tightly fixed to the main solenoid valve 140A, perforated into the body at the first side, and bent vertically downward to extend to the bottom so that the sample injection device 130 side and the first port P1 are extended. The first flow path 141 to connect, the second flow path 142, the third side connecting the carrier gas side and the second port (P2) by being bored into the body from the second side and extended vertically downward to the bottom The third flow path 143 connecting the non-catalytic thermal combustion oxidation reactor 120 and the second port P2 by perforating into the body and extending vertically downward to the bottom, perforating into the body from the fourth side. And vertically bent downward to extend to a bottom surface, a fourth flow path 144 connecting the drain side and the third port P3 in the normal open mode of the solenoid valve is formed, wherein the second flow path 142 and the third flow path are formed. Euro (143) Folded vertically downward portion is the distribution that is formed so as to cross each other connected to the jig (140B);
Cooling unit 150 for cooling the gas vaporized by the non-catalyst thermal combustion oxidation reactor 120;
A discharge device (152) for discharging the condensed water by cooling by the cooling unit (150);
A carrier gas pump 162 for supplying a carrier gas 160;
Total organic carbon minimized the deviation of the measured value due to air flow fluctuations, characterized in that it comprises a detector 170 for detecting the oxidized nitrogen oxide and total organic carbon contained in the gas cooled by the cooling unit 150 And total nitrogen content measuring device. The lower cap 180 of the TIC port 122,
A lower cap body 1802 having an upper opening and an air inlet 1803 on the side thereof;
A glass filter 1804 placed on the inner bottom of the lower cap body 1802 that is open; And
The O-ring 1806 seals the sample water in the cylindrical body 1222 so as not to leak to the outside by being placed on the upper surface of the glass filter 1804; Organic carbon and total nitrogen content measuring device. The said dispensing jig of Claim 1 or 2,
The first to fourth side surfaces are formed at an inclined downward slope and are perforated toward the inside of the body in the inclined surface direction, so that the angles at which the flow paths are bent into the ports P1, P2, and P3 are greater than 90 degrees and smaller than 180 degrees. A total organic carbon and total nitrogen content measuring device which minimizes the deviation of the measured value due to air flow fluctuation. The said dispensing jig of Claim 1 or 2,
The upper flow paths of the second flow path 142 and the third flow path 143 are formed in such a manner that their ends intersect with each other while being at least 90 degrees or less than 180 degrees or in a straight line with each other. Minimized total organic carbon and total nitrogen content measurement device.

Images