VOCs gas monitoring device

Abstract

The utility model relates to the technical field of gas monitoring, and particularly discloses a VOCs (volatile organic compounds) gas monitoring device which comprises a main pipeline, a plurality of electromagnetic air valves communicated with the bottom of the main pipeline, an axial flow fan communicated with the top end of the middle of the main pipeline, a guide cylinder communicated with the exhaust end of the axial flow fan, and a monitoring cavity shell sleeved outside the guide cylinder. A flow guide pipe A and a flow guide pipe B are arranged on the circumferential surface of the flow guide cylinder in a communicating manner, a VOCs gas concentration electrochemical sensor is detachably mounted at the top of an inner cavity of the monitoring cavity shell, and a controller electrically connected with the VOCs gas concentration electrochemical sensor is arranged outside the monitoring cavity shell. The main pipeline of the device is provided with a plurality of electromagnetic air valves, a plurality of monitoring points are covered, when the specific area where the VOCs gas concentration exceeds the standard is detected, all the areas are tested in sequence in the mode that only one electromagnetic air valve is opened, the flow guide efficiency can be improved by only opening one electromagnetic air valve, and the detection accuracy is improved. Meanwhile, whether the concentration of the VOCs gas in the area exceeds the standard or not can be accurately and quickly obtained.

Description

Technical Field

[0001] This utility model relates to the field of gas monitoring technology, and more specifically, to a monitoring device for VOCs gas. Background Technology

[0002] High concentrations of VOCs (such as benzene and formaldehyde) can irritate the respiratory mucosa, causing symptoms such as dizziness and nausea. For example, when the benzene concentration in a furniture factory workshop exceeded the standard by 10 times, workers experienced acute poisoning reactions after short-term exposure. Monitoring can provide timely warnings and allow for protective measures. VOCs concentration monitoring is a core link connecting environmental management, health protection, and industrial development, providing early warnings of acute and chronic exposure risks and protecting the public and occupational groups. Currently, there are many high-risk points for VOCs gas leaks in workshops, requiring the installation of multiple VOCs gas sensors for monitoring. While installing too many VOCs gas sensors can solve the problem of multi-point monitoring, it is too costly. It may require multiple controllers to handle the fluctuations in electrical signals from multiple VOCs gas sensors, further increasing costs. Therefore, we propose a VOCs gas monitoring device. Utility Model Content

[0003] In view of the above-mentioned technical problems in related technologies, this utility model provides a VOCs gas monitoring device that can solve the above problems.

[0004] To achieve the above-mentioned technical objectives, the technical solution of this utility model is implemented as follows:

[0005] The VOCs gas monitoring device includes a main pipeline. Several electromagnetic valves are connected to the bottom of the main pipeline. An axial flow fan is connected to the top of the middle section of the main pipeline. A guide tube is installed at the exhaust end of the axial flow fan. A monitoring chamber shell is fitted outside the guide tube. Guide tube A and guide tube B are connected to the circumference of the guide tube. An electrochemical sensor for VOCs gas concentration is detachably installed at the top of the inner cavity of the monitoring chamber shell. A controller electrically connected to the electrochemical sensor for VOCs gas concentration is installed outside the monitoring chamber shell.

[0006] Furthermore, the top of the electromagnetic valve is connected to the connecting cylinder by bolts, and an indicator light is fixedly installed on the outer surface of the connecting cylinder. The top of the connecting cylinder is connected to the bottom of the main pipe.

[0007] Furthermore, inside the guide tube, from bottom to top, there are right-angle tube B and right-angle tube A, with right-angle tube B connected to guide tube B and right-angle tube A connected to guide tube A.

[0008] Furthermore, both right-angle tube B and right-angle tube A have tapered flares at their bottoms, with the maximum diameter of the tapered flares being two-thirds of the diameter of the inner cavity of the guide tube.

[0009] Furthermore, a hemispherical cover is fixedly installed on the top of the guide tube by a bracket.

[0010] Furthermore, a cover is detachably installed at the top of the monitoring chamber shell via bolts, the VOCs gas concentration electrochemical sensor is fixed to the bottom of the cover with screws, and the controller is fixed to the top of the cover.

[0011] The beneficial effects of this utility model are as follows: The main pipeline of the device of this application is equipped with multiple electromagnetic air valves, covering multiple monitoring points. When detecting which area has excessive VOCs gas concentration by the electrochemical sensor, each area can be tested sequentially by opening only one electromagnetic air valve. Opening only one electromagnetic air valve can improve the flow efficiency and at the same time, it can accurately and quickly determine whether the VOCs gas concentration in that area exceeds the standard.

[0012] By setting diversion guide pipes and hemispherical covers on both the side wall and top of the guide tube, the airflow guided by the axial flow fan is buffered, allowing the airflow to slowly fill the monitoring chamber. This facilitates sufficient contact and reaction between the VOCs gas concentration electrochemical sensor and the inhaled guided gas, thereby ensuring the VOCs gas concentration electrochemical sensor and gas detection reaction time. Attached Figure Description

[0013] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0014] The present invention will now be described in further detail with reference to the accompanying drawings.

[0015] Figure 1 This is a schematic diagram of a VOCs gas monitoring device;

[0016] Figure 2 It is a cross-sectional view of the inside of the monitoring chamber and the guide tube;

[0017] Figure 3 This is a schematic diagram of the flow guide tube.

[0018] In the picture:

[0019] 1. Main pipe; 2. Connecting cylinder; 3. Indicator light; 4. Electromagnetic valve; 5. Axial flow fan; 6. Flow guide tube; 7. Monitoring chamber shell; 701. Through groove; 8. Controller; 9. Cover; 10. VOCs gas concentration electrochemical sensor; 11. Hemispherical cover; 12. Flow guide tube A; 1201. Right angle tube A; 13. Flow guide tube B; 1301. Right angle tube B. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model are within the protection scope of the present utility model.

[0021] like Figure 1-3 As shown, the present invention discloses a VOCs gas monitoring device, including a main pipeline 1. Several electromagnetic valves 4 are connected to the bottom of the main pipeline 1. An axial flow fan 5 is connected to the top of the middle part of the main pipeline 1. A guide tube 6 is installed at the exhaust end of the axial flow fan 5. A monitoring chamber shell 7 is sleeved on the outside of the guide tube 6. A guide pipe A12 and a guide pipe B13 are connected to the circumferential surface of the guide tube 6. A VOCs gas concentration electrochemical sensor 10 is detachably installed at the top of the inner cavity of the monitoring chamber shell 7. A controller 8 is provided on the outside of the monitoring chamber shell 7 and is electrically connected to the VOCs gas concentration electrochemical sensor 10.

[0022] Example 1: The electromagnetic valve 4 is a valve body assembly driven by a motor to rotate the valve plate. The servo controllers driving the motor of the electromagnetic valve 4 are integrated on the controller 8 via wires. The VOCs gas concentration electrochemical sensor 10 is a detection device that converts gas concentration into an electrical signal output through an electrochemical reaction. The electrochemical sensor works by reacting with the gas being measured and generating an electrical signal proportional to the gas concentration. A typical electrochemical sensor consists of a sensing electrode (or working electrode) and a counter electrode, separated by a thin electrolytic layer. The gas first passes through a tiny capillary-shaped opening and reacts with the sensing electrode. The gas diffuses through the barrier and reacts with the sensing electrode. The sensing electrode can employ an oxidation or reduction mechanism. Through the resistor connected between the electrodes, a current proportional to the concentration of the gas being measured flows between the positive and negative electrodes. Measuring this current determines the gas concentration. The VOCs gas concentration electrochemical sensor 10 is electrically connected to the controller 8. The controller 8 receives the current value change of the VOCs gas concentration electrochemical sensor 10, thereby determining the gas concentration. In the initial state, each electromagnetic valve 4 is opened, and the main pipeline 1 covers each high-risk area for VOCs gas leakage. In the area where electromagnetic valve 4 is located, which is prone to VOCs gas leakage, axial flow fan 5 is running continuously, generating negative pressure at each electromagnetic valve 4. When the electrochemical sensor 10 detects a VOCs gas leak, staff close all electromagnetic valves 4 and open only one at a time to investigate each area. When the electrochemical sensor 10 detects a high VOCs gas concentration at the point where electromagnetic valve 4 is open (according to the "Emission Standard of Pollutants for Synthetic Resin Industry" (GB31572-2015): NM The emission limit for HC is 60-100 mg / m³; the emission limit for NMHC in the "Emission Standard of Pollutants for Petrochemical Industry" (GB31571-2015) is 60-120 mg / m³; the emission limit for NMHC in the "Emission Standard of Air Pollutants for Coatings, Inks and Adhesives Industry" (GB37824-2019) is 50-60 mg / m³ under specific processes (exceeding the minimum value of the range is considered as a high gas concentration). In this case, the indicator light 3 on the corresponding connecting cylinder 2 will be turned on to mark the area, which will facilitate the staff to conduct a detailed inspection of the area.

[0023] In the preferred technical solution, the top of the electromagnetic valve 4 is connected to the connecting cylinder 2 by bolts. An indicator light 3 is fixedly installed on the outer surface of the connecting cylinder 2. The top of the connecting cylinder 2 is connected to the bottom of the main pipe 1. When the VOCs gas concentration in the test area is too high, the indicator light 3 on the corresponding connecting cylinder 2 is turned on to mark the area, so that personnel can quickly obtain the location of the area with high VOCs gas concentration.

[0024] In the preferred technical solution, right-angle tubes B1301 and A1201 are arranged sequentially from bottom to top inside the flow guide tube 6. Right-angle tube B1301 is connected to flow guide tube B13, and right-angle tube A1201 is connected to flow guide tube A12. Both right-angle tubes B1301 and A1201 have tapered flares at their bottoms. The maximum diameter of the tapered flares is two-thirds of the inner diameter of the flow guide tube 6. The right-angle tubes, together with the tapered flares and the angled flow guide tubes, can turbulently slow down the airflow, allowing the airflow to slowly fill the monitoring chamber shell 7. This is beneficial for the VOCs gas concentration electrochemical sensor 10 to fully contact and react with the inhaled guided gas.

[0025] In the preferred technical solution, a hemispherical cover 11 is fixedly installed on the top of the guide tube 6 by a bracket, and the hemispherical cover 11 can also buffer the airflow.

[0026] In the preferred technical solution, a cover 9 is detachably installed at the top of the monitoring chamber shell 7 by bolts. The VOCs gas concentration electrochemical sensor 10 is fixed to the bottom of the cover 9 by screws, and the controller 8 is fixed to the top of the cover 9. The VOCs gas concentration electrochemical sensor 10 has a short service life. The cover 9 is detachable, which facilitates the replacement and maintenance of the VOCs gas concentration electrochemical sensor 10.

[0027] In practical use, each electromagnetic valve 4 is opened, the main pipeline 1 covers each high-risk area for VOCs gas leakage, the electromagnetic valve 4 is located in the high-risk area for VOCs gas leakage, the axial flow fan 5 is running continuously, and negative pressure is generated at each electromagnetic valve 4. When a VOCs gas leakage occurs in a certain area, the negative pressure airflow will fill the monitoring chamber shell 7 with VOCs gas after passing through the electromagnetic valve 4, connecting cylinder 2, main pipeline 1, axial flow fan 5, guide cylinder 6, and buffered by guide pipe A12, guide pipe B13 and hemispherical cover 11. The VOCs gas concentration value is detected by the VOCs gas concentration electrochemical sensor 10. Then, the staff will close all electromagnetic valves 4 and open only one electromagnetic valve 4 at a time to check each area. When the VOCs gas concentration electrochemical sensor 10 detects that the VOCs gas concentration at the opening of the electromagnetic valve 4 is high, the indicator light 3 on the corresponding connecting cylinder 2 will be turned on to mark the area, which will facilitate the staff to carry out detailed investigation of the area.

[0028] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A VOCs gas monitoring device, characterized in that, The system includes a main pipe (1), with several electromagnetic air valves (4) connected to the bottom of the main pipe (1), an axial flow fan (5) connected to the top of the middle part of the main pipe (1), a guide tube (6) connected to the exhaust end of the axial flow fan (5), a monitoring chamber shell (7) sleeved on the outside of the guide tube (6), a guide pipe A (12) and a guide pipe B (13) connected to the circumferential surface of the guide tube (6), a VOCs gas concentration electrochemical sensor (10) detachably installed on the top of the inner cavity of the monitoring chamber shell (7), and a controller (8) electrically connected to the VOCs gas concentration electrochemical sensor (10) is provided on the outside of the monitoring chamber shell (7).

2. The VOCs gas monitoring device according to claim 1, characterized in that, The top of the electromagnetic air valve (4) is connected to the connecting cylinder (2) by bolts. An indicator light (3) is fixedly installed on the outer surface of the connecting cylinder (2). The top of the connecting cylinder (2) is connected to the bottom of the main pipe (1).

3. The VOCs gas monitoring device according to claim 1, characterized in that, Inside the guide tube (6), right-angle tube B (1301) and right-angle tube A (1201) are arranged sequentially from bottom to top. Right-angle tube B (1301) is connected to guide tube B (13), and right-angle tube A (1201) is connected to guide tube A (12).

4. The VOCs gas monitoring device according to claim 3, characterized in that, Both the right-angle tube B (1301) and the right-angle tube A (1201) are provided with tapered flares at the bottom, and the maximum diameter of the tapered flares is two-thirds of the inner diameter of the guide tube (6).

5. The VOCs gas monitoring device according to claim 1, characterized in that, The top of the guide tube (6) is fixed with a hemispherical cover (11) by a bracket.

6. The VOCs gas monitoring device according to claim 1, characterized in that, The top of the monitoring chamber shell (7) is detachably fitted with a cover (9) by bolts. The VOCs gas concentration electrochemical sensor (10) is fixed to the bottom of the cover (9) by screws. The controller (8) is fixed to the top of the cover (9).

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