Combustible and explosive gas on-line monitoring system

Abstract

The utility model discloses a combustible and explosive gas on-line monitoring system which comprises an FID (Flame Ionization Detector), a jet pump, a first pressure controller, a second pressure controller, a first negative pressure control module, a second negative pressure control module, a gas resistor and a pipeline for gas transmission among all parts. An inlet and an outlet of the FID detector are respectively connected with a first negative pressure control module and a second negative pressure control module, the inlet and the outlet are communicated with each other through a quick bypass and then are connected with the jet pump at the outlet, and by adjusting the power air pressure of the jet pump and adjusting the first negative pressure control module and the second negative pressure control module, the air pressure of the jet pump can be adjusted. And the vacuum degree and the pressure difference of the inlet and the outlet of the FID detector are ensured. The accuracy and the stability in the monitoring process can be ensured by accurately controlling the vacuum degrees of the inlet and the outlet, the whole set of system can realize online long-term continuous automatic operation monitoring, and the system is quick in response, low in cost, simple and convenient to operate and easy to maintain.

Description

Technical Field

[0001] The utility model relates to the technical field of online monitoring, in particular to an online monitoring system for flammable and explosive gases. Background Art

[0002] As we all know, with the development of science and technology, the atmospheric environment is also polluted. The culprit of pollution is volatile organic compounds (VOCs). Now RTO, DTO, CRO and other treatment equipment are widely used in the field of VOCs treatment in various industries. Their main function is to burn or catalyze at high temperature, and through chemical or biochemical reactions, convert VOCs into carbon dioxide and water to meet environmental protection requirements.

[0003] Usually, flammable and explosive gas monitoring systems mostly use infrared detectors. However, infrared detectors do not absorb all compounds, so they are only suitable for measuring one or several combustible gases in mixed combustible gases. In actual working conditions, the composition of the monitored object is complex and changeable, and the infrared gas detector cannot detect many gases, which will make the measured value lower than the actual value. This will result in the inability to alarm when the gas reaches the alarm threshold and take emergency measures, which may cause danger. Therefore, the infrared gas detectors currently used in large quantities for combustible gas detection cannot meet the requirements for monitoring the lower explosion limit of combustible gases with complex compositions.

[0004] Secondly, some monitoring systems using FID detectors require the assistance of a diaphragm pump or other external power equipment to introduce the sample to be tested into the system for testing. However, the use of a diaphragm pump will cause large fluctuations in the pressure in the injection tube, resulting in a large deviation between the measurement result and the actual result. At the same time, the risk of accidents such as explosions and fires caused by electric sparks generated by its power supply cannot be avoided. Utility Model Content

[0005] The purpose of this section is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and utility model name of this application to avoid blurring the purpose of this section, specification abstract and utility model name, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0006] In view of the above problems existing in the existing on-line monitoring system for flammable and explosive gases, the present utility model is proposed.

[0007] Therefore, the purpose of the utility model is to provide an online monitoring system for flammable and explosive gases, which solves the shortcomings of the existing infrared detection technology, such as strict requirements on the gas to be measured, inability to monitor flammable and explosive gases with complex components, frequent maintenance of optical equipment and high cost, large pressure fluctuations and inability to accurately measure, while completely avoiding the risk of accidents such as explosions and fires caused by sparks generated by its power supply.

[0008] In order to solve the above technical problems, the utility model provides the following technical solutions: an online monitoring system for flammable and explosive gases, comprising an FID detector, a jet pump, a first pressure controller, a second pressure controller, a first negative pressure control module, a second negative pressure control module, an air resistor and a pipeline for gas transmission between the components, characterized in that the inlet and outlet of the FID detector are respectively connected to the first negative pressure control module and the second negative pressure control module, and the inlet and outlet are interconnected by a quick bypass, and then connected to the jet pump at the outlet, and the vacuum degree and pressure difference between the inlet and outlet of the FID detector are ensured by adjusting the pressure of the jet pump power gas and the adjustment of the first negative pressure control module and the second negative pressure control module, so as to monitor the flammable and explosive gases in real time.

[0009] As a preferred solution of the online monitoring system for flammable and explosive gases described in the utility model, wherein: the first negative pressure control module and the second negative pressure control module respectively control the pressure at the inlet and outlet of the FID detector; by adjusting the front-end air supply volume, different vacuum degrees are provided for the inlet and outlet of the first negative pressure control module and the second negative pressure control module respectively.

[0010] As a preferred solution of the on-line monitoring system for flammable and explosive gases described in the utility model, the FID detector is connected to two gas sources, the first one is a hydrogen pipeline, and the second one is an air pipeline. The two gas sources include hydrogen, air, range gas, zero gas and gas to be measured, and the two gas sources respectively provide the fuel gas and combustion-supporting gas required for combustion. The hydrogen pipeline is connected to a second pressure controller for adjusting and controlling the pressure of the hydrogen; the air pipeline is connected to a first pressure controller for adjusting and controlling the pressure.

[0011] As a preferred solution of the on-line monitoring system for flammable and explosive gases described in the utility model, the jet pump is connected with a power gas pipeline to provide high-speed fluid for the jet pump, so that negative pressure is generated in the jet pump to form a vacuum, thereby sucking the gas to be measured into the combustion chamber of the FID detector. The jet pump, driven by the power gas source, provides different vacuum degrees for the inlet and outlet of the first negative pressure control module and the second negative pressure control module respectively. The power gas pipeline includes but is not limited to compressed air and cylinder nitrogen.

[0012] As a preferred solution of the on-line monitoring system for flammable and explosive gases described in the utility model, the hydrogen pipeline of the FID detector is connected with a range gas pipeline and a zero gas pipeline, and after being mixed with hydrogen, the range gas and the zero gas enter the combustion chamber. The range gas and the zero gas are used for calibration of the system to ensure that the measured value truly reflects the actual situation of the sample.

[0013] As a preferred solution of the online monitoring system for flammable and explosive gases of the utility model, the hydrogen pipeline of the FID detector is also connected to a pipeline of gas to be tested, and after being mixed with hydrogen, the gas enters the combustion chamber from the hydrogen interface of the FID detector and is then detected after combustion.

[0014] As a preferred solution of the online monitoring system for flammable and explosive gases described in the utility model, wherein: a first air resistance is arranged and connected between the second negative pressure control module and the hydrogen pipeline interface; a second air resistance is arranged and connected between the second negative pressure control module and the junction of the range gas pipeline, the zero point gas pipeline and the gas pipeline to be measured.

[0015] As a preferred solution of the on-line monitoring system for flammable and explosive gases of the utility model, a fast bypass is arranged between the inlet and the outlet of the FID detector, and a third gas resistance is arranged and connected to the fast bypass.

[0016] As a preferred solution of the on-line monitoring system for flammable and explosive gases described in the utility model, the range gas or zero-point gas or the gas to be measured is divided into two paths after passing through the second gas block, a small amount of gas is mixed with hydrogen after passing through the first gas block and enters the combustion chamber of the FID detector, the output end of the jet pump is connected to the tail exhaust pipeline, and a large amount of gas flows directly out of the tail exhaust pipeline of the jet pump from the fast bypass through the third gas block.

[0017] Beneficial effects of the utility model: The utility model solves the shortcomings of the infrared detection technology in the prior art, such as strict requirements on the gas to be measured, inability to monitor flammable and explosive gases with complex components, frequent maintenance of optical equipment and high cost, large pressure fluctuations and inability to accurately measure, while completely avoiding the risk of accidents such as explosions and fires caused by electric sparks generated by its power supply. In addition, the precise control of the inlet and outlet vacuum degrees in the system can ensure the accuracy and stability of the monitoring process. The entire system can realize online long-term continuous automatic operation monitoring, and has fast response, low cost, simple operation and easy maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following briefly introduces the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0019] Figure 1 The figure is a schematic diagram of the system structure of the on-line monitoring system for flammable and explosive gases of the utility model. DETAILED DESCRIPTION

[0020] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0022] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0023] Secondly, the present invention is described in detail with reference to the schematic diagram. When describing the embodiments of the present invention, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present invention. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0024] Reference Figure 1 , provides an online monitoring system for flammable and explosive gases, including an FID detector 1, a jet pump 2, a first pressure controller 3, a second pressure controller 4, a first negative pressure control module 5, a second negative pressure control module 6, an air resistor and a pipeline for gas transmission between the various components, characterized in that the inlet and outlet of the FID detector 1 are respectively connected to the first negative pressure control module 5 and the second negative pressure control module 6, the inlet and outlet are interconnected by a fast bypass, and are connected to the jet pump 2 at the outlet, and the vacuum degree and pressure difference between the inlet and outlet of the FID detector 1 are ensured by adjusting the power gas pressure of the jet pump 2, as well as the adjustment of the first negative pressure control module 5 and the second negative pressure control module 6, so as to monitor the flammable and explosive gases in real time.

[0025] Among them, the first negative pressure control module 5 and the second negative pressure control module 6 respectively control the pressure at the inlet and outlet of the FID detector 1; by adjusting the front-end air supply volume, different vacuum degrees are provided for the inlet and outlet of the first negative pressure control module 5 and the second negative pressure control module 6 respectively.

[0026] Among them, the FID detector 1 is connected to two gas sources, the first one is a hydrogen pipeline 23, and the second one is an air pipeline 22. The two gas sources include hydrogen, air, range gas, zero gas and gas to be measured. The two gas sources respectively provide the fuel gas and combustion-supporting gas required for combustion. The hydrogen pipeline 23 is connected to a second pressure controller 4 for adjusting and controlling the pressure of the hydrogen; the air pipeline 22 is connected to a first pressure controller 3 for adjusting and controlling the pressure.

[0027] Furthermore, the jet pump 2 is connected to a power gas pipeline 21 to provide high-speed fluid for the jet pump, so that negative pressure is generated in the jet pump to form a vacuum, thereby sucking the gas to be tested into the combustion chamber of the FID detector 1. Driven by the power gas source, the jet pump 2 provides different vacuum degrees for the inlet and outlet of the first negative pressure control module 5 and the second negative pressure control module 6 respectively. The power gas pipeline 21 includes but is not limited to compressed air and cylinder nitrogen.

[0028] Among them, the hydrogen pipeline 23 of the FID detector 1 is connected to the range gas pipeline 24 and the zero gas pipeline 25, and after being mixed with hydrogen, the range gas and the zero gas are used for calibration of the system to ensure that the measured value truly reflects the actual situation of the sample. The hydrogen pipeline 23 of the FID detector 1 is also connected to the test gas pipeline 26, and after being mixed with hydrogen, the gas enters the combustion chamber from the hydrogen interface of the FID detector 1 and is detected after combustion.

[0029] Specifically, a first air resistor 7 is provided between the second negative pressure control module 6 and the interface of the hydrogen pipeline 23; a second air resistor 8 is provided between the second negative pressure control module 6 and the confluence of the range gas pipeline 24, the zero point gas pipeline 25 and the gas to be measured 26; a quick bypass is provided between the inlet and the outlet of the FID detector 1, and a third air resistor 9 is provided on the quick bypass; the range gas or the zero point gas or the gas to be measured is divided into two paths after passing through the second air resistor 8, a small amount of gas is mixed with hydrogen after passing through the first air resistor 7 and enters the combustion chamber of the FID detector 1; the output end of the jet pump 2 is connected to the tail exhaust pipeline, and a large amount of gas flows directly out from the tail exhaust pipeline 27 of the jet pump 2 after passing through the third air resistor 9 from the quick bypass.

[0030] The utility model solves the shortcomings of the infrared detection technology in the prior art, such as strict requirements on the gas to be measured, inability to monitor flammable and explosive gases with complex components, frequent maintenance of optical equipment and high cost, large pressure fluctuations and inability to accurately measure, and the like. At the same time, it completely avoids the risk of accidents such as explosions and fires caused by electric sparks generated by its power supply. In addition, the precise control of the inlet and outlet vacuum degrees in the system can ensure the accuracy and stability of the monitoring process. The entire system can realize online long-term continuous automatic operation monitoring, and has fast response, low cost, simple operation and easy maintenance.

[0031] It should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model has been described in detail with reference to the preferred embodiments, ordinary technicians in the field should understand that the technical solution of the utility model can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the utility model, which should be included in the scope of the claims of the utility model.

Claims

1. An online monitoring system for flammable and explosive gases, comprising an FID detector (1), a jet pump (2), a first pressure controller (3), a second pressure controller (4), a first negative pressure control module (5), a second negative pressure control module (6), a gas block and a pipeline for gas transmission between the components, characterized in that: The inlet and outlet of the FID detector (1) are connected to a first negative pressure control module (5) and a second negative pressure control module (6) respectively. The inlet and outlet are interconnected via a quick bypass and are connected to a jet pump (2) at the outlet. By adjusting the pressure of the power gas of the jet pump (2) and the first negative pressure control module (5) and the second negative pressure control module (6), the vacuum degree and pressure difference between the inlet and outlet of the FID detector (1) are ensured, and flammable and explosive gases are monitored in real time.

2. The on-line monitoring system for flammable and explosive gases according to claim 1 is characterized in that: The first negative pressure control module (5) and the second negative pressure control module (6) respectively control the pressure at the inlet and outlet of the FID detector (1); and different vacuum degrees are provided at the inlet and outlet of the first negative pressure control module (5) and the second negative pressure control module (6) respectively by adjusting the front-end air supply volume.

3. The on-line monitoring system for flammable and explosive gases according to claim 2 is characterized in that: The FID detector (1) is connected to two gas sources, the first of which is a hydrogen pipeline (23) and the second is an air pipeline (22). The two gas sources include hydrogen, air, span gas, zero gas and gas to be measured, and the two gas sources respectively provide fuel gas and combustion-supporting gas required for combustion. The hydrogen pipeline (23) is connected to a second pressure controller (4) for adjusting and controlling the pressure of the hydrogen; and the air pipeline (22) is connected to a first pressure controller (3) for adjusting and controlling the pressure.

4. The on-line monitoring system for flammable and explosive gases according to claim 3 is characterized in that: The jet pump (2) is connected to a power gas pipeline (21) to provide high-speed fluid to the jet pump, so that negative pressure is generated in the jet pump to form a vacuum, thereby sucking the gas to be tested into the combustion chamber of the FID detector (1). The jet pump (2) is driven by a power gas source to provide different vacuum degrees for the inlet and outlet of the first negative pressure control module (5) and the second negative pressure control module (6). The power gas pipeline (21) includes but is not limited to compressed air and cylinder nitrogen.

5. The on-line monitoring system for flammable and explosive gases according to claim 4 is characterized in that: The hydrogen pipeline (23) of the FID detector (1) is connected to a span gas pipeline (24) and a zero gas pipeline (25), and after being mixed with hydrogen, the span gas and the zero gas are introduced into the combustion chamber. The span gas and the zero gas are used for calibration of the system to ensure that the measured value truly reflects the actual situation of the sample.

6. The on-line monitoring system for flammable and explosive gases according to claim 5 is characterized in that: The hydrogen pipeline (23) of the FID detector (1) is also connected to a test gas pipeline (26), and after being mixed with hydrogen, the gas enters the combustion chamber from the hydrogen interface of the FID detector (1) and is then burned and detected.

7. The on-line monitoring system for flammable and explosive gases according to claim 6 is characterized in that: A first air resistor (7) is provided between the second negative pressure control module (6) and the interface of the hydrogen gas pipeline (23); and a second air resistor (8) is provided between the second negative pressure control module (6) and the junction of the range gas pipeline (24), the zero point gas pipeline (25), and the gas pipeline to be measured (26).

8. The on-line monitoring system for flammable and explosive gases according to claim 7 is characterized in that: A quick bypass is provided between the inlet and the outlet of the FID detector (1), and a third gas resistance (9) is provided and connected to the quick bypass.

9. The on-line monitoring system for flammable and explosive gases according to claim 8 is characterized in that: The span gas or zero-point gas or gas to be measured is divided into two paths after passing through the second gas block (8); a small amount of gas passes through the first gas block (7) and mixes with hydrogen to enter the combustion chamber of the FID detector (1); the output end of the jet pump (2) is connected to a tail exhaust pipeline, and a large amount of gas passes through the third gas block (9) from the fast bypass and directly flows out from the tail exhaust pipeline (27) of the jet pump (2).

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