A wall-mounted constant temperature control box with calibration function

Abstract

The invention relates to a wall-mounted thermostatic control box with a calibration function, which comprises a calibration system and a mixing system, wherein the calibration system is connected to a chromatograph via the mixing system; the mixing system of the invention fundamentally mixes liquid nitrogen and sample gas into a self-circulating mixing pipeline mechanism, and is released by heating and gasification, so that the liquid nitrogen and the sample gas are fully mixed; the self-circulating mixing pipeline mechanism utilizes a combination of an arc section and a trumpet section to utilize liquid nitrogen gasification to promote the mutual flow of internal gas, so that the sample gas and nitrogen generated by liquid nitrogen gasification are fully mixed, especially the organic phase in the sample gas is well released into the nitrogen atmosphere during the process of heating from low temperature; the mixed gas after such a mixing treatment can reduce the fluctuation of the detection value of the chromatograph, so that the detection data is more credible and the data processing is easier.

Description

Technical Field

[0001] The invention belongs to the technical field of gas online monitoring, and in particular relates to a wall-mounted constant temperature control box with a calibration function. Background Art

[0002] Volatile Organic Compounds (VOC) are referred to as VOC. At present, the VOC online monitoring system is an integrated system that provides gas monitoring services for the environmental monitoring industry, which can realize online monitoring of the main components and total amount of organic waste gas. The online monitor adopts advanced intelligent component analysis algorithms and FID technology, collects, processes, analyzes, stores and uploads real-time measurement data of gas through high-precision AD sampling, and monitors the total VOC concentration, main component concentration, and total emission in real time.

[0003] Gas online monitoring equipment generally needs to be equipped with a constant temperature control box. The constant temperature control box is a standard pretreatment equipment. Its main function is to maintain the temperature stability of the gas entering the VOC online monitoring equipment to prevent the sample temperature from being too high or too low, which may cause damage to the internal detection unit of the VOC online monitoring equipment. The problem with the constant temperature control box in the prior art is that the standard gas and the sample gas are not mixed sufficiently when they are mixed into the VOC online monitoring equipment. Therefore, when the mixed gas passes through the detection unit, its composition is in a fluctuating state, resulting in fluctuations in the detection data, and multiple algorithm processing is required to obtain reliable data. Summary of the invention

[0004] The purpose of the present invention is to provide a wall-mounted constant temperature control box with calibration function, which can mix the calibration gas and the sample gas evenly, in order to solve the above problems.

[0005] The present invention achieves the above-mentioned purpose through the following technical solutions:

[0006] A wall-mounted constant temperature control box with a calibration function comprises a calibration system and a mixing system, wherein the calibration system comprises an air extraction pump, a six-way valve and a quantitative ring, wherein the inlet of the air extraction pump is connected to the sample gas inlet through a pipeline, the outlet is connected to port 5 of the six-way valve through a pipeline, port 6 of the six-way valve is connected to the full-course calibration outlet through a pipeline, a quantitative ring is connected between port 4 and port 1 of the six-way valve, port 2 of the six-way valve is connected to the inlet of the mixing system, and port 3 of the six-way valve is connected to the calibration gas inlet through a pipeline; the mixing system comprises a No. 1 three-way valve, a self-circulating mixing pipeline mechanism, a heating unit, an air inlet nozzle, an air outlet nozzle, an air inlet valve and an air outlet valve, the self-circulating mixing pipeline mechanism is a symmetrical structure, comprising an upper unit and a lower unit, and both the upper unit and the lower unit comprise an arc segment, a connecting The arc section comprises a section, a trumpet section, a connecting section and a middle section, the two ends of the arc section are respectively connected to the wide-mouth ends of the two trumpet sections through the connecting section, the narrowed sections of the two trumpet sections are directly connected through the connecting section, the middle part of the connecting section is connected to one end of the middle section, and the other end of the middle section is connected to the middle part of the arc section, the arc sections of the upper unit and the lower unit are connected as a whole to form a connected part, the two sides of the connected part are respectively connected to the air inlet nozzle and the air outlet nozzle, the air outlet nozzle and the air inlet nozzle are both connected to the internal space of the arc section, the air inlet nozzle is provided with an air inlet valve, the air outlet pipe is provided with an air outlet valve, the air inlet nozzle is connected to the lower port of No. 1 three-way valve, the left port of No. 1 three-way valve is connected to the outlet of the calibration system, the right port of No. 1 three-way valve is connected to the carrier gas inlet, and the air outlet nozzle is connected to the sample gas inlet of the chromatograph; a heating unit is provided on the arc section.

[0007] As a further optimization solution of the present invention, the calibration gas is liquid nitrogen.

[0008] As a further optimization solution of the present invention, the internal spaces of the arc-shaped segments of the upper unit and the lower unit are interconnected.

[0009] As a further optimization solution of the present invention, the heating unit is an electric heating wire, and the electric heating wire is surrounded by the outside of the arc segment.

[0010] As a further optimization scheme of the present invention, the chromatograph adopts a gas chromatograph in the prior art. The detection return port of the chromatograph is connected to the inlet of the water-gas separator through a pipeline, and the water outlet of the water-gas separator is connected to the wastewater collection pipeline. The detection return port discharges the waste gas after the detection, and the gas phase of the waste gas after water-gas separation is discharged into the atmosphere from the gas outlet, and the water outlet is discharged into the wastewater collection pipeline for collection.

[0011] As a further optimization scheme of the present invention, the calibration system is also connected to a backflush system, and the backflush system is used to backflush the pipeline of the calibration system. The backflush system includes a compressed air source, a solenoid valve and a No. 2 three-way valve. The compressed air source is connected to the upper port of the No. 2 three-way valve through a pipeline and a solenoid valve, and the left and right ports of the No. 2 three-way valve are respectively connected to the sample gas inlet and the suction pump inlet. The No. 2 three-way valve switches the two gas sources of compressed air and sample gas to enter the suction pump. When the left port is switched to be connected with the right port, the sample gas enters the suction pump. When the upper port is switched to be connected with the right port, the compressed air enters the suction pump, and the calibration system pipeline is backflush cleaned.

[0012] The beneficial effects of the present invention are:

[0013] 1) The mixing system of the present invention is fundamentally to mix liquid nitrogen and sample gas into a self-circulating mixing pipeline mechanism, and to release the liquid nitrogen and sample gas by heating and gasification, so that the liquid nitrogen and sample gas are fully mixed. The self-circulating mixing pipeline mechanism utilizes the combination of the arc section and the trumpet section to utilize the liquid nitrogen gasification to promote the mutual flow of the internal gas, so that the sample gas and the nitrogen generated by the liquid nitrogen gasification are fully mixed, especially the organic phase in the sample gas is well released into the nitrogen atmosphere during the process of heating from low temperature. The mixed gas after such a mixing treatment can reduce the fluctuation of the detection value of the chromatograph, make the detection data more reliable, and make the data processing easier;

[0014] 2) The present invention uses a six-way valve in conjunction with a quantitative ring structure to calibrate the sample gas, and can conveniently switch to the standard gas channel, so that the standard gas can be better mixed with the sample gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic diagram of the system structure of the present invention in Example 1;

[0016] Figure 2 Schematic diagram of the valve port of the six-way valve when the quantitative loop of the present invention in Example 1 intercepts the sample gas;

[0017] Figure 3 Schematic diagram of the valve port of the six-way valve when the standard gas of the present invention is mixed with the sample gas in the first embodiment;

[0018] Figure 4 It is a structural schematic diagram of the self-circulating mixing pipeline mechanism of the present invention in embodiment 1.

[0019] In the figure: an air pump 101, a six-way valve 102, and a quantitative ring 103;

[0020] Three-way valve No. 1 201, self-circulating mixing pipeline mechanism 202, heating unit 203, air inlet nozzle 204, air outlet nozzle 205, air inlet valve 206, air outlet valve 207;

[0021] The arc section 2021, the connecting section 2022, the trumpet section 2023, the connecting section 2024, the middle section 2025, and the connected part 2026;

[0022] Solenoid valve 301, three-way valve No. 2 302. DETAILED DESCRIPTION

[0023] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0024] Embodiment 1

[0025] like Figure 1-4 As shown, a wall-mounted constant temperature control box with a calibration function includes a calibration system and a mixing system. The calibration system is connected to a chromatograph via the mixing system. The calibration system calibrates the sample gas, obtains a calibration amount of the sample gas, and after preliminary mixing with the standard gas in the calibration system, the sample gas enters the mixing system and is fully mixed with the standard gas, and then is sent to the chromatograph via the carrier gas to monitor the sample gas.

[0026] The calibration system includes an air pump 101, a six-way valve 102 and a quantitative ring 103. The inlet of the air pump 101 is connected to the sample gas inlet through a pipeline, the outlet is connected to port 5 of the six-way valve 102 through a pipeline, port 6 of the six-way valve 102 is connected to the full calibration outlet through a pipeline, a quantitative ring 103 is connected between ports 4 and 1 of the six-way valve 102, port 2 of the six-way valve 102 is connected to the inlet of the mixing system, and port 3 of the six-way valve 102 is connected to the calibration gas inlet through a pipeline.

[0027] The method of calibrating the sample gas of the calibration system is as follows: the valve port of the six-way valve 102 is switched to connect port 2 with port 3, port 1 with port 6, and port 5 with port 4; the vacuum pump 101 draws the sample gas into port 6; the sample gas passes through port 6, port 1, quantitative ring 103, port 4, and port 5 in sequence; a quantitative amount of the sample gas is intercepted by the quantitative ring 103, and the remaining sample gas is discharged from the full-course calibration outlet;

[0028] Method for mixing sample gas and standard gas of calibration system: valve port of six-way valve 102 is switched to connect port 2 with port 1, port 3 with port 4, port 5 with port 6; standard gas enters port 3, passes through port 3, port 4, quantitative ring 103, port 1 and port 2 in sequence; when standard gas passes through quantitative ring 103, it is mixed with quantitative sample gas retained in quantitative ring 103 and finally output from port 2 to the mixing system.

[0029] The mixing system includes a No. 1 three-way valve 201, a self-circulating mixing pipeline mechanism 202, a heating unit 203, an air inlet nozzle 204, an air outlet nozzle 205, an air inlet valve 206 and an air outlet valve 207. The self-circulating mixing pipeline mechanism 202 is a symmetrical structure, including an upper unit and a lower unit. The upper unit and the lower unit both include an arc section 2021, a connecting section 2022, a trumpet section 2023, a connecting section 2024 and a middle section 2025. The two ends of the arc section 2021 are respectively connected to the wide-mouth ends of the two trumpet sections 2023 through the connecting section 2022, the narrowed sections of the two trumpet sections 2023 are directly connected through the connecting section 2024, the middle part of the connecting section 2024 is connected to one end of the middle section 2025, and the middle section 2025 is connected to the middle section 2025. The other end of 025 is connected to the middle part of the arc segment 2021, and the arc segments 2021 of the upper unit and the lower unit are connected as a whole to form a connected part 2026. The two sides of the connected part 2026 are respectively connected to the air inlet nozzle 204 and the air outlet nozzle 205. The air outlet nozzle 205 and the air inlet nozzle 204 are both connected to the internal space of the arc segment 2021. The air inlet nozzle 204 is provided with an air inlet valve 206, and the air outlet pipe is provided with an air outlet valve 207. The air inlet nozzle 204 is connected to the lower port of the No. 1 three-way valve 201, the left port of the No. 1 three-way valve 201 is connected to the No. 2 port of the six-way valve 102, the right port of the No. 1 three-way valve 201 is connected to the carrier gas inlet, and the air outlet nozzle 205 is connected to the sample gas inlet of the chromatograph; a heating unit 203 is provided on the arc segment 2021.

[0030] If necessary, the standard gas is liquid nitrogen and the carrier gas is nitrogen.

[0031] The mixing principle of the mixing system: First, the No. 1 three-way valve 201 is switched to connect the left and lower ports, and the mixed gas of the standard gas and the sample gas enters the arc section 2021 of the upper unit and the lower unit from the air inlet nozzle 204, and then is heated and vaporized by the heating unit 203 from the liquid nitrogen. The vaporization increases the total amount of gas phase, and the internal air pressure of the arc section 2021 increases. The airflow flows through the connecting section 2022 to the wide-mouth end of a trumpet section 2023, and the airflow enters the contracted section through the wide-mouth end of the trumpet section 2023. Due to the change in the caliber, the connecting section in the middle Negative pressure is generated in the connecting section 2024, and gas is drawn in from the middle section 2025, and then flows out from another trumpet section 2023. The kinetic energy of the gas flow is actually provided by the gasification of liquid nitrogen. Before the liquid nitrogen is completely gasified, the internal gasification will continuously cause the internal airflow to flow between the arc section 2021 and the trumpet section 2023, producing a good mixing effect in the completely sealed space. Only after the liquid nitrogen is completely gasified can the gas inside the self-circulating mixing pipeline mechanism 202 enter a stable state.

[0032] After a certain period of time (preferably 30 seconds) during the above-mentioned intake process, the mixed gas containing the sample gas completely enters the annular tube. At this time, the valve on the intake nozzle 204 is closed, and the valve on the outlet nozzle 205 is initially in a closed state. At this time, the mixed gas is enclosed in the self-circulating mixing pipeline mechanism 202.

[0033] After a certain period of time (preferably 1 to 2 minutes), the liquid nitrogen in the mixed gas is fully vaporized. At this time, the outlet valve 207 is opened, and the gas in the self-circulating mixing pipeline mechanism 202 is discharged from the outlet nozzle 205 due to the high pressure and enters the sample gas inlet of the chromatograph, and the amount of volatile organic matter is monitored online by the chromatograph.

[0034] When the chromatograph needs to be cleaned, the No. 1 three-way valve 201 is switched to connect the right port and the lower port, and then the air inlet valve 206 and the air outlet valve 207 are opened. The carrier gas enters the self-circulating mixing pipeline mechanism 202 through the No. 1 three-way valve 201, and then enters the chromatograph sample gas inlet, and the chromatograph is cleaned by a pure carrier gas.

[0035] In this embodiment, the inner spaces of the arc segments 2021 of the upper unit and the lower unit are connected to each other.

[0036] In this embodiment, the heating unit 203 is a heating wire, and the heating wire surrounds the outside of the arc segment 2021 .

[0037] In this embodiment, the chromatograph adopts a gas chromatograph in the prior art. The detection return port of the chromatograph is connected to the inlet of the water-gas separator through a pipeline, and the water outlet of the water-gas separator is connected to the wastewater collection pipeline. The detection return port discharges the waste gas after the detection, and the gas phase of the waste gas after water-gas separation is discharged into the atmosphere from the gas outlet, and the water outlet is discharged into the wastewater collection pipeline for collection.

[0038] The calibration system is also connected to a backflush system, which is used to backflush the pipeline of the calibration system. The backflush system includes a compressed air source, a solenoid valve 301 and a No. 2 three-way valve 302. The compressed air source is connected to the upper port of the No. 2 three-way valve 302 through a pipeline and the solenoid valve 301, and the left and right ports of the No. 2 three-way valve 302 are respectively connected to the sample gas inlet and the inlet of the suction pump 101. The No. 2 three-way valve 302 switches the two gas sources of compressed air and sample gas to enter the suction pump 101. When the left port is switched to be connected with the right port, the sample gas enters the suction pump 101. When the upper port is switched to be connected with the right port, the compressed air enters the suction pump 101, and the calibration system pipeline is backflush cleaned.

[0039] Necessarily, a constant temperature system is provided in the same manner as the constant temperature control box in the prior art, but it only acts on the section after the gas outlet nozzle 205, that is, only the gas discharged from the gas outlet nozzle 205 is subjected to constant temperature treatment.

[0040] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A wall-mounted constant temperature control box with calibration function, characterized in that: The invention comprises a calibration system and a mixing system, wherein the calibration system comprises an air pump, a six-way valve and a quantitative ring, the inlet of the air pump is connected to the sample gas inlet through a pipeline, the outlet is connected to port 6 of the six-way valve through a pipeline, port 5 of the six-way valve is connected to the full calibration outlet through a pipeline, a quantitative ring is connected between port 4 and port 1 of the six-way valve, port 2 of the six-way valve is connected to the inlet of the mixing system, and port 3 of the six-way valve is connected to the calibration gas inlet through a pipeline; the mixing system comprises a No. 1 three-way valve, a self-circulating mixing pipeline mechanism, a heating unit, an air inlet nozzle, an air outlet nozzle, an air inlet valve and an air outlet valve, the self-circulating mixing pipeline mechanism is a symmetrical structure, comprising an upper unit and a lower unit, and the upper unit and the lower unit both comprise an arc section, a connecting section, a horn section, a connecting section, a The arc section and the middle section, the two ends of the arc section are connected to the wide-mouth ends of the two trumpet sections through the connecting section respectively, the contracted sections of the two trumpet sections are directly connected through the connecting section, the middle part of the connecting section is connected to one end of the middle section, and the other end of the middle section is connected to the middle part of the arc section, the arc sections of the upper unit and the lower unit are connected as a whole to form a connected part, the two sides of the connected part are respectively connected to the air inlet nozzle and the air outlet nozzle, the air outlet nozzle and the air inlet nozzle are both connected to the internal space of the arc section, the air inlet nozzle is provided with an air inlet valve, the air outlet pipe is provided with an air outlet valve, the air inlet nozzle is connected to the lower port of No. 1 three-way valve, the left port of No. 1 three-way valve is connected to the outlet of the calibration system, the right port of No. 1 three-way valve is connected to the carrier gas inlet, and the air outlet nozzle is connected to the sample gas inlet of the chromatograph; a heating unit is provided on the arc section; The calibration gas is liquid nitrogen, and the inner spaces of the arc-shaped sections of the upper unit and the lower unit are interconnected.

2. A wall-mounted constant temperature control box with calibration function according to claim 1, characterized in that: The heating unit is an electric heating wire, which surrounds the outside of the arc segment.

3. A wall-mounted constant temperature control box with calibration function according to claim 1, characterized in that: The detection return port of the chromatograph is connected to the inlet of the water-gas separator through a pipeline, and the water outlet of the water-gas separator is connected to the wastewater collection pipeline.

4. A wall-mounted constant temperature control box with calibration function according to claim 1, characterized in that: The calibration system is also connected to a backflush system, which is used to backflush the pipeline of the calibration system. The backflush system includes a compressed air source, a solenoid valve and a No. 2 three-way valve. The compressed air source is connected to the upper port of the No. 2 three-way valve through a pipeline and a solenoid valve. The left and right ports of the No. 2 three-way valve are respectively connected to the sample gas inlet and the vacuum pump inlet.

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