Sample pretreatment device of organic carbon analyzer

Abstract

The utility model discloses a sample pretreatment device of an organic carbon analyzer. The four-way valve comprises a valve body, three single-clack type check valves, three sealing turnbuckles, a liquid inlet, a bottle cap portion, an oxygen port and a liquid taking port, the valve body is integrally formed by the liquid inlet, the oxygen port, the liquid taking port and the bottle cap portion, the liquid inlet, the oxygen port and the liquid taking port are each internally provided with one sealing turnbuckle, the liquid taking port faces the bottle cap portion under the liquid taking port, and the bottle cap portion is provided with one sealing turnbuckle. The bottle cap part provided with the sealing rubber ring is installed outside the bottle opening of the sample bottle in a sealing mode, and the inner side of each sealing turnbuckle is provided with a matched single-clack type check valve. In the preparation process of a sample solution, pollution can be effectively reduced, the inlet directions of the solution and gas are increased, the test time is shortened, and the material cost is effectively saved.

Description

Technical Field

[0001] The utility model belongs to the technical field of preparing samples for testing, and particularly relates to a sample pretreatment device for degassing samples of an organic carbon analyzer. Background Art

[0002] Carbon elements in water are divided into total carbon (TC), inorganic carbon (IC), and total organic carbon (TOC). The sum of inorganic carbon (IC) and total organic carbon (TOC) is total carbon (TC); among them, total organic carbon is further divided into purgeable organic carbon (POC) and non-purgeable organic carbon (NPOC). Total organic carbon (TOC) is measured by a special instrument - a total organic carbon analyzer. The testing methods include the direct method and the difference method. In the direct method, the water sample is first acidified and then aerated to decompose inorganic carbonates into carbon dioxide. After the carbon dioxide is removed, the sample solution is injected into a high-temperature combustion tube and oxidized into carbon dioxide at high temperature for measurement. However, during the aeration process of the sample solution, volatile organic compounds will be lost, resulting in measurement errors. This testing method can only determine the value of non-purgeable organic carbon. The difference method is to inject the sample solution into a high-temperature combustion tube (900 °C) and a low-temperature reaction tube (150 °C) respectively. The solution is catalytically oxidized at high temperature in the high-temperature combustion tube and acidified and aerated in the low-temperature reaction tube to convert both organic compounds and inorganic carbonates into carbon dioxide. This test result is the total carbon; the secondary sample solution is acidified and aerated in the low-temperature reaction tube to decompose inorganic carbonates into carbon dioxide, and this test result is the inorganic carbon (IC); the difference between the total carbon (TC) and the inorganic carbon (IC) is the total organic carbon (TOC). Before sample injection, the sample solution will be oxygen-injected. The main purpose is to increase the oxygen content of the sample solution and drive out other gases, such as carbon dioxide in the air. However, exhausting only through the oxygen-injection method cannot drive out all the gases completely, resulting in the contamination of the sample solution when measuring inorganic carbon (IC) and total organic carbon (TOC), affecting the accuracy of the test results, with a high detection limit, serious test interference, and inaccurate results. The above situations have a great impact on the accuracy of the test results. Therefore, it is necessary to study and improve the oxygen-injection device for sample pretreatment. Content of the Utility Model

[0003] In view of the problems existing in the background art, the utility model provides a sample pretreatment device for an organic carbon analyzer. The technical solution is as follows: it includes a four-way valve and a sample bottle. The four-way valve includes a valve body, three single-flap check valves, three sealing screw threads, a liquid inlet, a bottle cap part, an oxygen port, and a liquid extraction port. The valve body is integrally formed by the liquid inlet, the oxygen port, the liquid extraction port, and the bottle cap part. A sealing screw thread is installed in each of the liquid inlet, the oxygen port, and the liquid extraction port. The liquid extraction port faces the bottle cap part directly below it, and the bottle cap part with a sealing rubber ring is hermetically installed outside the bottle mouth of the sample bottle. A matching single-flap check valve is installed inside each sealing screw thread.

[0004] The liquid inlet is connected to the sample solution container through an autosampler; the oxygen inlet is connected to an external pressurized oxygen source; the liquid sampling device extends from the liquid sampling port into the sample bottle for sampling.

[0005] The sample bottle is placed in an ultrasonic instrument.

[0006] The sealing screw buckle includes: a columnar buckle body, an external thread part, a sealing ring and a through hole. The external thread part and the sealing ring are respectively arranged at one end outside the circumferential surface of the columnar buckle body. A through hole is opened in the center of the columnar buckle body. The external thread part matches the internal thread at the installation position, and the sealing screw buckle matches the single-flap check valve inside.

[0007] The columnar buckle body and the through hole are coaxial.

[0008] The single-flap check valve includes: a valve flap, a hinge mounting part, a check valve sealing rubber ring and a spring. One end of the valve flap is mounted on the inner wall of the valve body through the hinge mounting part, and the other end of the valve flap presses on the check valve sealing rubber ring. The check valve sealing rubber ring is arranged inside the through hole of the corresponding sealing screw buckle.

[0009] The beneficial effects of the present utility model are as follows: during the preparation process of the sample solution, pollution can be effectively reduced, the directions of the solution and gas entering are increased, the degassing time of the sample is reduced, and the material cost is effectively saved. Description of the Drawings

[0010] Figure 1 It is a schematic structural diagram of an embodiment of a sample pretreatment device for an organic carbon analyzer of the present utility model;

[0011] Figure 2 It is a schematic structural diagram of the sealing screw buckle cut in the embodiment of the present utility model;

[0012] Figure 3 It is a schematic structural diagram of the single-flap check valve in the embodiment of the present utility model.

[0013] Among them: 1 - sample bottle, 2 - liquid inlet, 3 - liquid sampling port, 4 - oxygen inlet, 5 - sealing screw buckle, 6 - sealing rubber ring, 7 - sealing gasket, 8 - ultrasonic instrument, 9 - single-flap check valve, 10 - four-way valve, 11 - bottle cap part, 12 - valve body, 13 - autosampler, 14 - sample solution container, 15 - pressurized oxygen source, 52 - columnar buckle body, 53 - external thread part, 51 - sealing ring, 54 - through hole, 91 - valve flap, 92 - hinge mounting part, 93 - check valve sealing rubber ring, 94 - spring. Detailed Embodiments

[0014] The following further elaborates on the present utility model in conjunction with the drawings.

[0015] As Figures 1 to 3The embodiment of the utility model shown includes: a four-way valve 10, a sample bottle 1, an ultrasonic instrument 8, a liquid extraction device, an auto-sampler 12, and a sample solution container 14. The four-way valve 10 includes: a valve body 13, three single-flap check valves 9, three sealing screw threads 5, a liquid inlet 2, a bottle cap part 11, an oxygen port 4, and a liquid extraction port 3. The four-way valve body 13 is integrally formed by the three valve ports of the liquid inlet 2, the oxygen port 4, and the liquid extraction port 3 and a bottle cap part 11. A sealing screw thread 5 is installed in each of the liquid inlet 2, the oxygen port 4, and the liquid extraction port 3. The liquid extraction port 3 faces the bottle cap part 11 directly below it. The bottle cap part 11 provided with a sealing rubber ring 6 is hermetically installed outside the bottle mouth of the sample bottle 1. The sample bottle 1 is placed in the ultrasonic instrument 8. When testers need to perform a large number of sample tests and require long-term sample injection, the ultrasonic instrument 8 can be added to effectively accelerate the degassing speed of the sample solution and reduce the sample injection time at the same time;

[0016] A matching single-flap check valve 9 is installed inside each sealing screw thread 5, effectively avoiding sample solution contamination caused by interface contamination, reducing the error generated by detection, and reducing the repetitive workload to a certain extent, ensuring the accuracy of the test results;

[0017] The liquid inlet 2 is connected to the sample solution container 14 through the auto-sampler 12, and the sample solution at the liquid inlet 2 is injected into the sample bottle 1 from the liquid inlet. The oxygen port 4 is connected to an external pressurized oxygen source 15, and the liquid extraction device (sampling needle) extends from the liquid extraction port 3 into the sample bottle 1 for sampling.

[0018] As Figure 2 The sealing screw thread 5 shown includes: a columnar buckle body 52, an external thread part 53, a sealing ring 51, and a through hole 54. The external thread part 53 and the sealing ring 51 are respectively arranged at one end outside the circumferential surface of the columnar buckle body 52. A coaxial through hole 54 is opened in the center of the columnar buckle body 52. The external thread part 53 matches the internal thread at the installation location (the liquid inlet 2, the oxygen port 4, and the liquid extraction port 3). The sealing screw thread 5 matches the single-flap check valve 9 inside, effectively avoiding sample solution contamination caused by interface contamination, reducing the error generated by detection, and reducing the repetitive workload to a certain extent, ensuring the accuracy of the test results.

[0019] As Figure 3The shown single - flap check valve 9 includes: a valve flap 91, a hinged mounting portion 92, a check valve sealing rubber ring 93, and a spring 94. One end of the valve flap 91 is mounted on the inner wall of the valve body 13 through the hinged mounting portion 92, and the other end of the valve flap 91 presses on the check valve sealing rubber ring 93. The check valve sealing rubber ring 93 is arranged inside the through - hole 54 of the corresponding sealing screw thread 5. The spring 94 is mounted on the hinged mounting portion 92 so that the valve flap 91 can press on the check valve sealing rubber ring 93 in the natural state. The single - flap check valve 9 installed in the through - hole 54 can effectively isolate the sample solution from the outside during the degassing operation of the sample solution, thus achieving a sealing effect. The corresponding check valve sealing rubber ring 93 can effectively perform one - way sealing of the liquid inlet 2, the oxygen port 4, and the liquid sampling port 3 and prevent contamination.

[0020] In this embodiment, the valve body 13, the columnar buckle body 52, the valve flap 91, and the hinged mounting portion 92 are all made of polytetrafluoroethylene (PTFE).

[0021] In this embodiment, the sealing rings, the sealing rubber rings, and the check valve sealing rubber ring 93 are made of rubber, and have good sealing performance.

[0022] During operation, the sample solution enters the sample bottle 1 from the liquid inlet 2. The sample bottle 1 and the four - way valve designed by the present utility model are tightly connected through the interface with the sealing rubber ring 6, so there will be no leakage under pressure. Subsequently, the oxygen port 4 starts to work for oxygen injection and pressurization, and the ultrasonic instrument 8 starts ultrasonic work. When the gas pressure in the sample bottle reaches 0.1 - 0.2 MPa and is maintained for 5 min; after being ultrasonically treated by the ultrasonic instrument 8, the sample solution in the sample bottle 1 completes the degassing operation. The sampling needle transports the sample solution to the instrument through the liquid sampling port 3. The sampling needle is supplied with the instrument. At this time, the sampling operation is completed. This operation has no exposed contact throughout the process, can ensure that the sample is not contaminated, and can effectively perform the pretreatment of the sample solution, making the interference in the sample solution eliminated more completely and reducing the detection limit.

Claims

1. A sample pretreatment device for an organic carbon analyzer, characterized in that: include: A four-way valve (10) and a sample bottle (1), wherein the four-way valve (10) comprises: a valve body (13), three single-flap check valves (9), three sealing screw buckles (5), a liquid inlet (2), a bottle cap (11), an oxygen port (4) and a liquid extraction port (3), wherein the valve body (13) is integrally formed by the liquid inlet (2), the oxygen port (4), the liquid extraction port (3) and the bottle cap (11), wherein each of the liquid inlet (2), the oxygen port (4) and the liquid extraction port (3) is provided with a sealing screw buckle (5), the liquid extraction port (3) faces the bottle cap (11) directly below it, and the bottle cap (11) provided with a sealing rubber ring (6) is sealed and installed outside the bottle mouth of the sample bottle (1), and a matching single-flap check valve (9) is installed inside each sealing screw buckle (5).

2. The sample pretreatment device for an organic carbon analyzer according to claim 1, characterized in that: The liquid inlet (2) is connected to a sample solution container (14) via an automatic sample injector (12); the oxygen port (4) is connected to an external pressurized oxygen source (15); and the liquid collection device extends from the liquid collection port (3) into the sample bottle (1) for sampling.

3. The sample pretreatment device for an organic carbon analyzer according to claim 1, characterized in that: The sample bottle (1) is placed in an ultrasonic instrument (8).

4. The sample pretreatment device for an organic carbon analyzer according to claim 1 or 2, characterized in that: The sealing spiral buckle (5) comprises: a columnar buckle body (52), an external threaded portion (53), a sealing ring (51) and a through hole (54), wherein the external threaded portion (53) and the sealing ring (51) are respectively arranged at one end outside the circumference of the columnar buckle body (52), a through hole (54) is opened in the center of the columnar buckle body (52), the external threaded portion (53) matches the internal thread of the installation position, and the sealing spiral buckle (5) matches the single-flap check valve (9) on the inside.

5. The sample pretreatment device for an organic carbon analyzer according to claim 4, characterized in that: The columnar buckle body (52) and the through hole (54) are coaxial.

6. The sample pretreatment device for an organic carbon analyzer according to claim 4, characterized in that: The single-flap check valve (9) comprises: a valve plate (91), a hinged mounting portion (92), a check valve sealing rubber ring (93) and a spring (94), wherein one end of the valve plate (91) is mounted on the inner wall of the valve body (13) via the hinged mounting portion (92), and the other end of the valve plate (91) is pressed on the check valve sealing rubber ring (93), and the check valve sealing rubber ring (93) is arranged on the inner side of the through hole (54) of the corresponding sealing spiral buckle (5).

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