Device and method capable of cleaning double-valve sampling air bags in batches

Abstract

The invention provides a device and method capable of cleaning double-valve sampling air bags in batches, the device comprises an air path system, an air pump and a controller, a plurality of double-valve air bags and a three-way valve are arranged on a main air conveying pipeline, the main air conveying pipeline is connected with an auxiliary air conveying pipeline through the three-way valve, and a valveless tee joint and the air pump are respectively arranged on the auxiliary air conveying pipeline. A controller is adopted to control an electromagnetic valve and a three-way valve which are arranged on a main gas conveying pipeline and a valveless tee joint and a gas pump which are arranged on an auxiliary gas conveying pipeline, and the operation of the gas pump is controlled according to a preset gear and gas extraction time. Therefore, the air bags are cleaned in batches, and working efficiency is improved. The utilization rate of cleaning gas is improved, and gas is saved; gas homogeneous phases are formed in the air bags, so that blank levels in the air bags cleaned in the same batch are close, errors caused by the air bags and parallel sample result deviation increase caused by the errors are reduced, and it is ensured that ecological environment monitoring data are comprehensive, accurate, objective and real; the number of the air bag connectors can be expanded according to needs, and use is flexible.

Description

Technical Field

[0001] The invention relates to the field of ecological environment monitoring, and in particular to a device and method for batch cleaning of double-valve sampling air bags. Background Art

[0002] When ecological and environmental monitoring personnel conduct gas monitoring, pollutants that cannot be monitored on site must be sampled and sent back to the laboratory for analysis. Air bag sampling is one of the sampling methods, which specifically involves sucking the measured gas into a clean air bag and transporting it back to the laboratory. The most critical point in this process is that the air bag must be clean, that is, it cannot affect the concentration of the pollutant being measured. Therefore, before sampling, the air bag must be cleaned with the specified gas multiple times (generally at least 3 times) until the blank test value meets the standard requirements. When there are many air bags, it will take a lot of time to clean each air bag separately. At the same time, the type of residual gas concentration after each air bag is used is different. For the air bag with lower residual gas concentration, it is cleaned 3 times, resulting in a waste of cleaning gas, and it may also make the blank level in the cleaned air bag uneven, which to a certain extent leads to an increase in the deviation of the test results between parallel samples. Summary of the invention

[0003] In view of the above problems, the present invention proposes a device and method for batch cleaning of double-valve sampling air bags. The air bags are connected in series to perform batch cleaning of the double-valve air bags. A mobile phase can be formed in the air bags to quickly carry away the residue in the air bags, saving gas used for cleaning the air bags. At the same time, it is also beneficial to form a uniform gas phase in the air bags, so that the blank levels in the air bags cleaned in the same batch are close, reducing the errors caused by the air bags and the increase in the deviation of parallel sample results caused by them, thereby ensuring that the ecological environment monitoring data is comprehensive, accurate, objective and true.

[0004] To achieve the above object, the present invention adopts the following technical solutions: The present invention provides a device capable of batch cleaning of double-valve sampling air bags, comprising: an air circuit system, an air pump and a controller. The air circuit system comprises an air inlet interface, a solenoid valve, a main air pipeline, an air bag interface and a three-way valve, an auxiliary air pipeline, a connecting pipeline, a valveless three-way, and a closed pipe section; the air bag interface is divided into an air inlet nozzle and an air outlet nozzle, which are respectively connected to the two interfaces on the double-valve air bag with a hose; the main air pipeline comprises several sections of pipelines, and an air inlet interface and an air bag interface are provided on the pipe section, which is connected to the solenoid valve at the air inlet end, and each pipe section is connected by a valveless three-way, and the end is a straight pipe; the auxiliary air pipeline comprises several The three-way valve is arranged on the main gas pipeline at the rear end of each air bag along the gas flow direction, and is connected to the auxiliary gas pipeline; the three-way valve on the main gas pipeline and the valveless three-way valve on the auxiliary gas pipeline are connected through a connecting pipe section; the controller is connected to the solenoid valve, the three-way valve on the main gas pipeline, the valveless three-way valve on the auxiliary gas pipeline and the air pump, and controls the operation of the air pump according to the preset gear position and air extraction time.

[0005] The air inlet interface is made of polytetrafluoroethylene and its size is consistent with that of the air bag interface.

[0006] The main gas transmission pipeline is made of polytetrafluoroethylene.

[0007] The air inlet nozzle and the air outlet nozzle are made of the same material and have the same inner diameter as the air inlet interface, and are respectively connected to the two interfaces on the double-valve air bag with hoses. The gas for cleaning the air bag enters the air bag from the air inlet nozzle, and then flows out from the air outlet nozzle into the main gas pipeline.

[0008] The air inlet of the three-way valve is connected to the air outlet nozzle end of the previous double-valve air bag, and the two air outlets are respectively connected to the main gas pipeline and the connecting pipeline connected to the valveless three-way on the secondary gas pipeline. The gas direction is adjusted according to usage requirements to keep the gas path unobstructed.

[0009] The air pump is a type of pump that prevents the pump body from directly contacting the gas.

[0010] The controller includes a flow adjustment gear and a time controller. The flow adjustment gear includes three gears, namely fast, medium and slow, and the corresponding flow rates are 1L / min, 3L / min and 10L / min respectively; the time controller is used to control the air intake time, and automatically stops the air intake after a certain time is set.

[0011] Preferably, the gas circuit system is expandable by sequentially adding a main gas pipeline section, an air bag interface, a three-way valve, a connecting pipeline, a valveless tee and an auxiliary gas pipeline section as needed.

[0012] The present invention also provides a method for batch cleaning of double-valve sampling air bags, which is processed by using the above-mentioned device for batch cleaning of double-valve sampling air bags, and comprises the following steps: S1. Connect the cleaning gas cylinder and turn on the pressure reducing valve switch on the cylinder to check whether there is enough gas; S2. Connect the pre-cleaned double-valve air bag, open the two valves on the air bag, adjust the three-way valve after the last air bag to the outlet to connect to the auxiliary gas pipeline, and adjust the three-way valve before it to the outlet to connect to the main gas pipeline; S3. Adjust the air intake position. The pressure in the gas cylinder presses the gas into the main gas pipeline, and then enters the connected air bags in turn and flows out through the auxiliary gas pipeline. S4, close the air inlet switch, turn on the air pump to start pumping air, and then turn off the air pump after all the air in the air bag is completely evacuated, thus completing one air bag cleaning; S5. If multiple cleanings are required, repeat the steps S2-S4 for multiple times. Later, the gas usage can be reduced by shortening the air intake time or turning on the air pump at the same time during air intake. S6. The gas outlet can be connected to an analytical instrument to analyze whether the gas blank value meets the standard requirements to determine whether the air bag needs to be cleaned further; S7. The number of air bags can be selected from 1 to more according to demand, and the corresponding three-way valve outlet is directly connected to the auxiliary gas pipeline.

[0013] Compared with the prior art, the beneficial effects achieved by the present invention are: 1. The air bags can be cleaned in batches to improve work efficiency; 2. The utilization rate of the cleaning gas can be improved to save gas; 3. It is conducive to forming a uniform gas phase in the air bags, so that the blank levels in the air bags cleaned in the same batch are close, reducing the errors caused by the air bags and the increase in the deviation of the parallel sample results caused by them, and ensuring that the ecological environment monitoring data is comprehensive, accurate, objective and true; 4. The number of air bag interfaces can be expanded as needed, and it is flexible to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of a device capable of batch cleaning of double-valve sampling air bags according to the present invention.

[0015] Legend: 1. Air inlet interface; 2. Main gas pipeline; 3. Air inlet nozzle; 4. Air outlet nozzle; 5. Hose; 6. Double-valve air bag; 7. Three-way valve; 8. Air pump; 9. Auxiliary gas pipeline; 10. Solenoid valve; 11. Valveless three-way valve; 12. Connecting pipeline; 13. Closed pipeline. DETAILED DESCRIPTION

[0016] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0017] like Figure 1As shown, a device capable of batch cleaning of double-valve sampling air bags of the present invention comprises three parts: an air circuit system, an air pump and a controller. The air circuit system comprises an air inlet interface 1, a solenoid valve 10, a main air pipeline 2, an air bag interface and a three-way valve 7, an auxiliary air pipeline 9, a connecting pipeline 12, a valveless three-way 11, and a closed pipe section 13; the air bag interface is divided into an air inlet nozzle 3 and an air outlet nozzle 4, which are respectively connected to the two interfaces on the double-valve air bag 6 by a hose 5; the main air pipeline comprises several sections of pipelines, and an air inlet interface and an air bag interface are provided on the pipe section, which are connected to the solenoid valve at the air inlet end, and each pipe section is connected by a three-way valve, and the end is a straight pipe; the auxiliary air pipeline is connected to the air bag interface by a three-way valve, and the end is a straight pipe; The gas pipeline includes several sections of pipelines, which are connected to the three-way valve and the air pump, and the sections are connected by valveless three-way valves; the three-way valve is arranged on the main gas pipeline at the rear end of each air bag along the gas flow direction, and is connected to the auxiliary gas pipeline; the three-way valve on the main gas pipeline and the valveless three-way valve on the auxiliary gas pipeline are connected by a connecting pipeline; the controller is connected to the solenoid valve, the three-way valve on the main gas pipeline, and the valveless three-way valve and the air pump on the auxiliary gas pipeline, and controls the operation of the air pump according to the preset gear position and air extraction time.

[0018] The air inlet interface 1 is made of polytetrafluoroethylene and has the same size as the air bag interface.

[0019] The main gas pipeline 2 is made of polytetrafluoroethylene.

[0020] The inlet nozzle 3 and the outlet nozzle 4 are made of the same material and have the same inner diameter as the inlet interface 1, and are respectively connected to the two interfaces on the double-valve air bag with hoses. The gas for cleaning the air bag enters the air bag from the inlet nozzle 3, and then flows out from the outlet nozzle 4 into the main gas pipeline.

[0021] The air inlet of the three-way valve 7 is connected to the air outlet nozzle end of the previous double-valve air bag, and the two air outlets are respectively connected to the main gas pipeline and the connecting pipeline connected to the valveless three-way on the secondary gas pipeline. The gas direction is adjusted according to the use requirements to keep the gas path unobstructed.

[0022] The air pump 8 is a type of pump that prevents the pump body from directly contacting the gas.

[0023] The controller includes flow adjustment gears and a time controller. The flow adjustment gears include three gears, namely fast, medium and slow, and the corresponding flow rates are 1 L / min, 3 L / min and 10 L / min respectively; the time controller is used to control the air intake time, and automatically stops the air intake after a certain time is set.

[0024] Preferably, the gas circuit system is expandable by sequentially adding a main gas pipeline section, an air bag interface, a three-way valve, a connecting pipeline, a valveless tee and an auxiliary gas pipeline section as needed. Example

[0025] A method for batch cleaning of double-valve sampling air bags is implemented by a device for batch cleaning of double-valve sampling air bags. This embodiment is carried out with three 3 L double-valve sampling air bags, and the specific operation steps are as follows: 1. Take a 4L high-pressure steel cylinder of hydrocarbon-removing air and connect the cylinder to the air inlet of the device through a pressure reducing valve and a polytetrafluoroethylene tube; 2. Connect the three air bags to the air bag interfaces on the main gas pipeline through hoses one by one. There should be no empty air bag interfaces between the three air bags on the main gas pipeline. 3. Adjust the three-way valve after the third air bag to the outlet to connect to the auxiliary gas pipeline, and adjust the three-way valves after the first and second air bags to the outlet to connect to the main gas pipeline; 4. Adjust the air intake position to "medium" and set the air intake time to 1 minute; 5. After the air intake is completed, the gas fills the three air bags, and then the air pump is turned on to extract the gas in the air bags and pipelines to complete the first air bag cleaning; 6. Adjust the air intake gear to "medium", do not set the air intake time, and turn on the air pump at the same time; 7. After continuous cleaning for 1 minute, turn off the air intake, and turn off the air pump after the air in the air bag and pipeline is completely pumped out; 8. The gas tail gas is connected to a portable gas chromatography-hydrogen flame ionization detector to detect the blank value. The total hydrocarbon mass concentration is 0.29 mg / m 3 (in terms of carbon), i.e. 0.39 mg / m 3 (measured in methane), less than the requirement of total hydrocarbon mass concentration ≤ 0.4 mg / m3 (measured in methane) in the blank test given in the "Determination of Total Hydrocarbons, Methane and Non-methane Total Hydrocarbons in Waste Gas from Stationary Pollution Sources by Portable Gas Chromatography-Hydrogen Flame Ionization Detector Method" (HJ 1332-2023); 9. After cleaning the air bag, close the air bag valve and remove it for later use. Comparative Example

[0026] When the three ordinary 3L air bags are cleaned by the traditional air bag cleaning device, each air bag needs to be cleaned at least three times, and about 9L of hydrocarbon-free air is used; when the device and method of the present invention are used, about 6L of hydrocarbon-free air is used, which reduces the cost and waste. At the same time, the air bags can be cleaned in batches, reducing manpower input and improving the work efficiency of the experimenters.

Claims

1. A device for batch cleaning of double-valve sampling air bags, comprising: An air circuit system, an air pump and a controller, characterized in that the air circuit system comprises an air inlet interface (1), a solenoid valve (10), a main air supply pipeline (2), an air bag interface and a three-way valve (7), an auxiliary air supply pipeline (9), a connecting pipeline (12), a valveless three-way (11), and a sealed pipe section (13); the air bag interface is divided into an air inlet nozzle (3) and an air outlet nozzle (4), which are respectively connected to two interfaces on a double-valve air bag (6) by a hose (5); the main air supply pipeline comprises a plurality of pipeline sections, each of which is provided with an air inlet interface and an air bag interface, which is connected to the solenoid valve at the air inlet end, and each of the pipeline sections is connected by a three-way valve. The auxiliary gas pipeline comprises a plurality of pipeline sections, which are connected to a three-way valve and an air pump, and each pipeline section is connected by a valveless three-way valve; the three-way valve is arranged on the main gas pipeline at the rear end of each air bag along the gas flow direction, and is connected to the auxiliary gas pipeline; the three-way valve on the main gas pipeline and the valveless three-way valve on the auxiliary gas pipeline are connected by a connecting pipe section; the controller is connected to the solenoid valve (10) and the three-way valve (7) on the main gas pipeline (2), and the valveless three-way valve (11) and the air pump (8) on the auxiliary gas pipeline (9), and controls the operation of the air pump according to a preset gear position and air extraction time.

2. The device according to claim 1, characterized in that: The air inlet interface (1) is made of polytetrafluoroethylene and has a size consistent with that of the air bag interface.

3. The device according to claim 1 or 2, characterized in that: The main gas transmission pipeline (2) is made of polytetrafluoroethylene.

4. The device according to claim 1 or 2, characterized in that: The material and inner diameter of the air inlet nozzle (3) and the air outlet nozzle (4) are the same as those of the air inlet interface (1), and are respectively connected to the two interfaces on the double-valve air bag by means of hoses. The gas for cleaning the air bag enters the air bag from the air inlet nozzle (3) and then flows out from the air outlet nozzle (4) into the main gas pipeline (2).

5. The device according to claim 1 or 2, characterized in that: The air inlet of the three-way valve (7) is connected to the air outlet nozzle (4) of the previous double-valve air bag, and the two air outlets are respectively connected to the main gas pipeline (2) and the connecting pipeline (11) connected to the valveless three-way valve (11) on the auxiliary gas pipeline (9), so as to adjust the gas flow according to the use requirements and keep the gas path unobstructed.

6. The device according to claim 1 or 2, characterized in that: The air pump (8) is a type of pump that prevents the pump body from directly contacting the gas.

7. The device according to claim 1 or 2, characterized in that: The controller includes flow adjustment gears and a time controller. The flow adjustment gears include three gears, namely fast, medium and slow, and the corresponding flow rates are 1L / min, 3L / min and 10L / min respectively; the time controller is used to control the air intake time, and automatically stops the air intake after a certain time is set.

8. The device according to claim 1 or 2, characterized in that: The gas circuit system can sequentially add a main gas pipeline section, an air bag interface, a three-way valve, a connecting pipeline, a valveless three-way valve and an auxiliary gas pipeline section as needed.

9. A method for batch cleaning of double-valve sampling air bags, using the device for batch cleaning of double-valve sampling air bags as claimed in any one of claims 1 to 8, comprising the following steps: S1. Connect the batch cleaning device of the double-valve sampling gas bag to the cleaning gas cylinder, and turn on the pressure reducing valve switch on the gas cylinder to check whether there is enough gas; S2, connect the pre-cleaned double-valve air bag (6), open the two valves on the double-valve air bag (6), adjust the three-way valve (7) after the last double-valve air bag (6) to the outlet connected to the auxiliary gas pipeline (9), and adjust the three-way valve (7) before it to the outlet connected to the main gas pipeline (2); S3, adjusting the air inlet gear position, the pressure in the gas cylinder presses the gas into the main gas pipeline (2), and then enters the connected double-valve air bag (6) in turn and then flows out through the auxiliary gas pipeline (9); S4, close the switch of the air inlet (1), turn on the air pump (8) to start pumping air, and then turn off the air pump (8) until all the air in the double-valve air bags (6) is completely evacuated, thereby completing one air bag cleaning; S5. When multiple cleaning is required, repeat the steps S2-S4 for multiple times. In the later stage, the gas intake time can be shortened or the gas pump (8) can be turned on simultaneously during the intake to reduce the gas consumption. S6. Connect the gas outlet to the analytical instrument to analyze whether the gas blank value meets the standard requirements, and determine whether the air bag needs to be cleaned further; S7. The number of air bags is selected from 1 to more than one according to the demand, and the corresponding three-way valve outlet is directly connected to the auxiliary air supply pipeline (9).

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