Calibration device and calibration method for toxic acid gas alarm

Abstract

The invention provides a calibration device and a calibration method for a toxic acid gas alarm. The calibration device comprises a standard gas steel cylinder (1) used for storing standard gas; the pressure reducing valve (2) is used for reducing pressure and adjusting gas flow; the gas path tee joint (3) is used for shunting gas; the sealing calibration cover (4) is used for sealing and covering a sensor shell of the alarm; the flow meter (5) is used for controlling the flow of bypass gas; the anti-suck-back gas washing device (6) is used for converting toxic acid gas into salt derivatives through an acid-base reaction; the gas dryer (7) is used for drying moisture in the tail gas; the temperature and humidity monitor (8) is used for detecting the temperature and humidity of the airflow; and the toxic gas residue monitor (9) is used for detecting the content of residual toxic acid gas. The calibration device and the calibration method of the toxic acid gas alarm meet the technical requirements of metrological verification regulations or calibration specifications, can effectively avoid harm of toxic acid gas to human bodies, and reduce environmental pollution.

Description

Technical Field

[0001] The present invention relates to the field of measurement and detection, and in particular to a calibration device and a calibration method for a toxic acid gas alarm. Background Art

[0002] Some toxic acidic gases are flammable, explosive, irritating and highly toxic. Even a small amount of leakage is enough to cause immeasurable harm to life and the environment, such as hydrogen cyanide, chlorine, hydrogen fluoride and hydrogen sulfide. Under the severe challenges of production safety and environmental protection, the accurate early warning of leaked toxic acidic gases by alarms has become an indispensable safety line of defense.

[0003] In order to ensure accurate early warning of toxic acid gas alarms in industrial production, metrology verification institutions need to calibrate the alarms installed at the production site. The relevant alarm calibration devices specified in the metrology verification procedures or calibration specifications include: cylinders for storing standard gas, pressure reducing valves, float flowmeters and calibration hoods. There is no toxic gas treatment device, and toxic gases are directly discharged into the air. Long-term breathing of toxic gases can easily cause acute poisoning of metrology technicians, and pollute the environment, which is not in line with the green and environmentally friendly metrology work concept.

[0004] Alarms for detecting toxic acidic gases are divided into self-priming and diffusion types according to the gas contact mode; and into handheld and fixed types according to the structural form. Handheld or self-priming alarms are equipped with a sealed calibration cover configured by the manufacturer, which can be directly sealed and connected for ventilation calibration. The sensor of the fixed diffusion alarm is hidden in a cylindrical explosion-proof metal shell with a gas contact hole at the bottom. The manufacturer may not be equipped with a calibration cover, or the calibration cover equipped cannot meet the sealing requirements. Therefore, it is necessary to design a calibration cover that meets the sealing requirements to prevent metrological technicians from directly contacting toxic acidic gases.

[0005] In summary, the on-site calibration device of the toxic acid gas alarm needs to be simple and practical, easy to disassemble and assemble, and portable, and comply with the technical requirements of relevant metrological verification procedures or calibration specifications. It can effectively protect the bodies of metrological technicians from being harmed by toxic gases, and the derivatives produced after treatment of the emitted toxic acid gases can be recycled or treated to reduce toxicity to avoid environmental pollution. Summary of the invention

[0006] In view of the above technical problems, the present invention proposes a calibration device for a toxic acidic gas alarm, which meets the technical requirements of the metrological verification procedures or calibration specifications, can effectively prevent metrological technicians from directly contacting toxic acidic gases or prevent toxic acidic hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide gases from being directly discharged into the ambient air to cause harm to the human body and the environment, and is portable, simple, practical and has low manufacturing and use costs.

[0007] Another technical problem to be solved by the present invention is a calibration method for calibrating a toxic acid gas alarm using the calibration device.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] A calibration device for a toxic acid gas alarm comprises a shell and a cover, and is characterized in that:

[0010] 1) A standard gas cylinder, a pressure reducing valve with a flow meter, a gas line tee, and a sealed calibration cover are installed outside the shell, and a flow meter, an anti-backflow gas washing device, a gas dryer, a temperature and humidity monitor, and a toxic gas residue monitor are installed inside the shell.

[0011] 2) A pressure reducing valve with a flow meter, a gas line tee, a sealed calibration cover, an anti-backflow gas washing device, a gas dryer, a temperature and humidity monitor, and a toxic gas residue monitor are connected in sequence through a gas pipeline to form a calibration gas circuit of the calibration device.

[0012] 3) A pressure reducing valve with a flow meter, a gas line tee, a flow meter, an anti-backflow gas washing device, a gas dryer, a temperature and humidity monitor, and a toxic gas residue monitor are connected in sequence through a gas pipeline to form a bypass gas path of the calibration device.

[0013] The purpose of the present invention can also be achieved by the following technical solutions:

[0014] Furthermore, the calibration object of the calibration device is a toxic acid gas alarm for detecting hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide gas.

[0015] Furthermore, the standard gas cylinder can be replaced with a cylinder with the same interface; the cylinder with the same interface respectively stores zero-point standard gas and toxic acidic standard gases of different types and concentrations; the zero-point standard gas is pure nitrogen standard gas; the toxic acidic standard gases of different types and concentrations are standard gases of different concentrations of hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide.

[0016] Further: the sealing calibration cover is composed of an elastic adapter sleeve, a fastening ring and a cylindrical cover; the two ends of the elastic adapter sleeve have different apertures, the end with a larger aperture is connected to the cylindrical cover; the end with a smaller aperture is connected to the sensor housing of the alarm; the fastening ring is made of metal and has a fastening screw and a fastening knob; the bottom end of the cylindrical cover is provided with a calibration cover air inlet pipe and a calibration cover air outlet pipe; the calibration cover air inlet pipe is located in the middle of the bottom of the cylindrical cover and is connected to the air circuit tee; the calibration cover air outlet pipe is located beside the bottom of the cylindrical cover and is connected to the anti-backflow washing device.

[0017] Furthermore: the anti-backflow scrubbing device is composed of an alkali solution storage container, a porous partition, an anti-backflow device, a gas dispersion device and an aeration device; the alkali solution storage container is filled with alkali solution, and a calibration gas path air inlet pipe, a bypass gas path air inlet pipe, a container air outlet pipe and an alkali solution inlet pipe are arranged at the top, and an alkali solution outlet pipe is arranged at the side end; the front end of the calibration gas path air inlet pipe is connected to a sealed calibration cover, and the end is connected to an anti-backflow device; the front end of the bypass gas path air inlet pipe is connected to a flowmeter, and the end is connected to an anti-backflow device; the porous partition is horizontally separated from the alkali solution in the alkali solution storage container, and the surface is sealed A small hole is opened in the collection; the anti-backflow device is a cylindrical cavity with openings at both ends, the upper opening is connected to the bypass calibration air path inlet pipe and the bypass air path inlet pipe, and the lower opening is connected to the gas dispersion device; the gas dispersion device is a gas path multi-channel structure, which is a device with an air inlet and multiple air outlets, the air inlet is connected to the anti-backflow device, and the air outlet is connected to the aeration device; the aeration device is a fine-pore joint; the container outlet pipe is connected to a gas dryer; the calibration air path inlet pipe, the bypass air path inlet pipe, the container outlet pipe, the alkali solution inlet pipe and the alkali solution outlet pipe are all provided with switches.

[0018] Furthermore: the gas dryer is a cylindrical cavity, with a dryer air inlet pipe and a dryer air outlet pipe provided at both ends of the cavity; the cylindrical cavity is filled with water-absorbing material; the dryer air inlet pipe is connected to an anti-backflow washing device; the dryer air outlet pipe is connected to a temperature and humidity monitor.

[0019] Furthermore: the temperature and humidity monitor is equipped with a temperature and humidity sensor, a numerical display component and an audible and visual alarm component, and the alarm value can be set; the temperature and humidity sensor is built into the gas path cavity; the gas path cavity is a cylindrical cavity, and a cavity air inlet pipe and a cavity air outlet pipe are provided at both ends of the cavity, the cavity air inlet pipe is connected to the gas dryer, and the cavity air outlet pipe is connected to the toxic gas residue monitor.

[0020] Furthermore: the toxic gas residue monitor is equipped with multiple sensor components, numerical display components and sound and light alarm components, and the alarm value can be set; the multiple sensor components are provided with a sealed shell, which are sensor components for detecting hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, sulfur dioxide and chlorine respectively; the sealed shell is provided with a shell air inlet pipe and a shell air outlet pipe, the shell air inlet pipe is connected to the temperature and humidity monitor, and the shell air outlet pipe is directly connected to the ambient air.

[0021] Furthermore: the cover body includes a side cover body and a top cover body, and the side cover body and the top cover body are connected by a lock; the side cover body is located on the side of the shell and is connected to the bottom of the shell through a connecting shaft; the top cover body is located at the top of the shell and is connected to the side of the shell through a connecting shaft.

[0022] Further: the calibration method of the calibration device for calibrating a toxic acid gas alarm is characterized by comprising the following calibration objects and steps:

[0023] Calibrate the self-priming alarm:

[0024] Step S1. Select a sensor assembly corresponding to the toxic acid standard gas for calibration and install it on the toxic gas residue monitor;

[0025] Step S2. Setting the alarm values ​​of the temperature and humidity monitor and the residual gas monitor;

[0026] Step S3. Adding alkali solution into the anti-backflow scrubbing device;

[0027] Step S4. Connect the self-priming alarm to the sealed calibration cover position;

[0028] Step S5. Turn on the flow meter switch to clear the bypass air path;

[0029] Step S6. Open the valve of the standard gas cylinder, and adjust the difference between the flow rate of the pressure reducing valve with a flow meter and the flow rate of the flow meter to be equal to the pump suction flow rate of the self-priming alarm;

[0030] Step S7. According to the technical requirements of the metrological verification procedure or calibration specification, the self-priming alarm is calibrated and calibrated using the zero-point standard gas and toxic acid standard gases of different concentrations through the calibration gas circuit and the bypass gas circuit.

[0031] To calibrate a diffusion alarm:

[0032] Step S1. Select a sensor assembly corresponding to the toxic acid standard gas for calibration and install it on the toxic gas residue monitor;

[0033] Step S2. Setting the alarm values ​​of the online temperature and humidity monitor and the residual toxic gas monitor;

[0034] Step S3. Adding alkali solution into the anti-backflow scrubbing device;

[0035] Step S4. Connecting the diffusion alarm to the sealed calibration cover;

[0036] Step S5. Turn off the flow meter switch and cut off the gas bypass pipeline;

[0037] Step S6. Open the valve of the standard gas cylinder and adjust the flow rate of the pressure reducing valve with flow meter to be consistent with the instructions of the alarm. If the instructions do not have clear requirements for the flow rate, it shall be consistent with the technical requirements of the metrological verification procedures or calibration specifications;

[0038] Step S7. According to the technical requirements of the metrological verification procedure or calibration specification, the diffusion alarm is calibrated and calibrated using the zero-point standard gas and toxic acid standard gases of different concentrations through the calibration gas circuit.

[0039] The beneficial effects of the present invention include:

[0040] 1) The calibration cover is sealed and connected to the alarm sensor housing through the elastic adapter sleeve of the sealed calibration cover, and the connection port is tightened with a fastening ring to prevent the connection port from leaking due to excessive purge air pressure or the calibration cover from falling off the alarm sensor housing. It not only seals the calibration gas path, but also allows the alarm to be calibrated without the need to hold the calibration cover, thereby preventing metrology technicians from close contact with the emitted toxic acidic gas and causing physical harm.

[0041] 2) Through the anti-backflow gas washing device, the toxic acidic gas components in the calibration gas line and the bypass gas line are converted into salt derivatives that can be recycled or treated to reduce toxicity using the acid-base reaction principle, which can avoid the direct discharge of toxic acidic gases into the ambient air, basically achieving zero emissions, and further avoiding toxic acidic gas pollution of the environment and possible harm to the bodies of metrological technicians.

[0042] 3) The accuracy of the toxic gas residue monitor is ensured by using a gas dryer and a temperature and humidity monitor. The toxic gas residue monitor is used to monitor the conversion effect of the toxic acid gas after the anti-backflow scrubbing device. When the concentration of the toxic acid gas exceeds the alarm value, the sound and light alarm will be activated. At this time, the valve switch of the standard gas cylinder must be closed in time, the calibration work must be stopped, and the alkali solution must be replaced in time to further avoid toxic acid gas pollution of the environment and possible harm to the body of the metrological technicians. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the structural framework of a specific embodiment.

[0044] Figure 2 Schematic diagram of the structure of the sealed calibration cover

[0045] Figure 3 Schematic diagram of the structure of the fastening ring

[0046] Figure 4 Schematic diagram of the structure of the cylindrical cover

[0047] Figure 5 Schematic diagram of the structure of the elastic transition sleeve

[0048] Figure 6 Structural diagram of the anti-backflow scrubbing device

[0049] Figure 7 Schematic diagram of the structure of the fine-pore joint DETAILED DESCRIPTION

[0050] In order to make the purpose, technical solutions and advantages of the embodiments of the invention clearer, the technical solutions in the embodiments of the invention are clearly and completely described below in conjunction with the drawings of the invention. Obviously, the described embodiments are only part of the embodiments of the invention, not all of the embodiments. Based on the embodiments of the invention, all other embodiments obtained by metrology technicians in this field without making creative work are within the scope of protection of the invention. Specific embodiment:

[0052] like Figure 1 A calibration device for a toxic acid gas alarm is shown, comprising a shell and a cover; the cover comprises a side cover and a top cover, the side cover and the top cover are connected by a lock; the side cover is located on the side of the shell and is connected to the bottom of the shell through a connecting shaft; the top cover is located at the top of the shell and is connected to the side of the shell through a connecting shaft. The double cover design is convenient for filling alkali liquid and discharging waste liquid; it is convenient for replacing the sensor components of the water-absorbing silica gel particles and the toxic gas residue monitor 9; it is convenient for observing the numerical changes of the temperature and humidity monitor 8 and the toxic gas residue monitor 9.

[0053] 1) A standard gas cylinder 1, a pressure reducing valve with a flow meter 2, a gas line tee 3, and a sealed calibration cover 4 are arranged outside the shell, and a flow meter 5, an anti-backflow gas washing device 6, a gas dryer 7, a temperature and humidity monitor 8, and a poisonous gas residue monitor 9 are arranged inside the shell.

[0054] 2) The standard gas cylinder 1, the pressure reducing valve with flow meter 2, the gas circuit tee 3, the sealed calibration cover 4, the anti-backflow gas washing device 6, the gas dryer 7, the temperature and humidity monitor 8 and the toxic gas residue monitor 9 are connected in sequence through a gas pipeline made of stainless steel or polytetrafluoroethylene to form a calibration gas circuit of the calibration device.

[0055] 3) The pressure reducing valve 2 with flow meter, the gas circuit tee 3, the flow meter 5, the anti-backflow gas washing device 6, the gas dryer 7, the temperature and humidity monitor 8 and the toxic gas residue monitor 9 are connected in sequence through a gas pipeline made of stainless steel or polytetrafluoroethylene to form a bypass gas circuit of the calibration device.

[0056] The calibration object of the calibration device is a poisonous acid gas alarm for detecting trace gases of hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide.

[0057] The standard gas cylinder 1 can be replaced with a cylinder with the same interface; the cylinders with the same interface respectively store zero-point standard gas and toxic acidic standard gases of different types and concentrations; the zero-point standard gas is pure nitrogen standard gas; the toxic acidic standard gases of different types and concentrations are standard gases of different concentrations of hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide.

[0058] like Figures 2 to 5 The sealing calibration cover 4 shown is composed of an elastic adapter sleeve, a fastening ring and a cylindrical cover; the two ends of the elastic adapter sleeve have different apertures, the end with a larger aperture is connected to the cylindrical cover; the end with a smaller aperture is connected to the sensor housing of the alarm; the fastening ring is made of metal and has a fastening screw and a fastening knob; a calibration cover air inlet pipe and a calibration cover air outlet pipe are provided at the bottom of the cylindrical cover; the calibration cover air inlet pipe is located in the middle of the bottom of the cylindrical cover and is connected to the air path tee 3; the calibration cover air outlet pipe is located beside the bottom of the cylindrical cover and is connected to the anti-backflow washing device 6.

[0059] like Figure 6 The anti-backflow scrubbing device 6 shown is composed of an alkali solution storage container, a porous partition, an anti-backflow device, a gas dispersion device and an aeration device; the alkali solution storage container is filled with alkali solution, and the alkali solution can be added to 1 / 2 of the container, and the top of the container is provided with a calibration gas path air inlet pipe, a bypass gas path air inlet pipe, a container air outlet pipe and an alkali solution inlet pipe, and the side end is provided with an alkali solution outlet pipe; the front end of the calibration gas path air inlet pipe is connected to a sealing calibration cover 4, and the end is connected to an anti-backflow device; the front end of the bypass gas path air inlet pipe is connected to a flowmeter 5, and the end is connected to the anti-backflow device; the porous partition is horizontally separated above the alkali solution in the alkali solution storage container, and can be placed At 1 / 3 of the distance from the top of the container, there are densely opened small holes on the surface; the anti-backflow device is a cylindrical cavity with openings at both ends, the upper opening is connected to the calibration gas path inlet pipe and the bypass gas path inlet pipe, and the lower opening is connected to the gas dispersion device; the gas dispersion device is a gas path multi-channel structure, which is a device with an air inlet and multiple air outlets, the air inlet is connected to the anti-backflow device, and the air outlet is connected to the aeration device; the aeration device is a fine-pore joint; the container outlet pipe is connected to the gas dryer 7; the calibration gas path inlet pipe, the bypass gas path inlet pipe, the container outlet pipe, the alkali solution inlet pipe and the alkali solution outlet pipe are all provided with switches.

[0060] The gas dryer 7 is a cylindrical cavity, with a dryer air inlet pipe and a dryer air outlet pipe provided at both ends of the cavity; the cylindrical cavity is filled with water-absorbing material; the dryer air inlet pipe is connected to the anti-backflow washing device 6; the dryer air outlet pipe is connected to the temperature and humidity monitor 8.

[0061] The temperature and humidity monitor 8 is provided with a temperature and humidity sensor, a numerical display component and an acoustic and optical alarm component, and the alarm value can be set; the temperature and humidity sensor is built into the gas path cavity; the gas path cavity is a cylindrical cavity, and a cavity air inlet pipe and a cavity air outlet pipe are arranged at both ends of the cavity, the cavity air inlet pipe is connected to the gas dryer 7, and the cavity air outlet pipe is connected to the toxic gas residual monitor 9. The numerical display component displays the gas temperature and humidity value in real time; the alarm value is the temperature and humidity valve limit value for the normal operation of the toxic gas residual monitor 9; the acoustic and optical alarm component sends out a physical acoustic and optical warning signal when the temperature and humidity exceed the set alarm value.

[0062] The toxic gas residual monitor 9 is provided with a variety of sensor components, numerical display components and sound and light alarm components, and the alarm value can be set; the various sensor components are provided with a sealed housing, which are sensor components for detecting hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, sulfur dioxide and chlorine respectively; the sealed housing is provided with a housing air inlet pipe and a housing air outlet pipe, the housing air inlet pipe is connected to the temperature and humidity monitor 8, and the housing air outlet pipe is directly connected to the ambient air. The numerical display component displays the residual toxic acid gas concentration value in real time; the alarm value is the concentration threshold value of the residual toxic acid gas emission; the sound and light alarm component sends out a physical sound and light warning signal when the residual toxic acid gas concentration exceeds the set alarm value.

[0063] The calibration method for calibrating a toxic acid gas alarm by the calibration device is characterized by comprising the following calibration objects and steps:

[0064] 1) Calibrate the self-priming alarm:

[0065] Step S1. Select a sensor assembly corresponding to the toxic acidic standard gas for calibration and install it on the toxic gas residue monitor 9;

[0066] Step S2. Setting the alarm values ​​of the temperature and humidity monitor 8 and the residual gas monitor 9;

[0067] Step S3. Adding alkali solution into the anti-backflow scrubbing device 6;

[0068] Step S4. Connect the self-priming alarm to the sealed calibration cover 4;

[0069] Step S5. Turn on the switch of flow meter 5 to clear the bypass air path;

[0070] Step S6. Open the valve of the standard gas cylinder 1, and adjust the difference between the flow rate of the pressure reducing valve 2 with a flow meter and the flow rate of the flow meter 5 to be equal to the pump suction flow rate of the self-priming alarm;

[0071] Step S7. According to the technical requirements of the metrological verification procedure or calibration specification, the self-priming alarm is calibrated and calibrated using the zero-point standard gas and toxic acid standard gases of different concentrations through the calibration gas circuit and the bypass gas circuit.

[0072] 2) Calibrate the diffusion alarm:

[0073] Step S1. Select a sensor assembly corresponding to the toxic acidic standard gas for calibration and install it on the toxic gas residue monitor 9;

[0074] Step S2. Setting the alarm values ​​of the temperature and humidity monitor 8 and the residual gas monitor 9;

[0075] Step S3. Adding alkali solution into the anti-backflow scrubbing device 6;

[0076] Step S4. Connecting the diffusion alarm to the sealed calibration cover 4;

[0077] Step S5. Turn off the switch of the flow meter 5 and cut off the gas bypass pipeline;

[0078] Step S6. Open the valve of the standard gas cylinder 1, and adjust the flow rate of the pressure reducing valve 2 with a flow meter to be consistent with the instructions of the alarm. If the instructions do not have clear requirements for the flow rate, it shall be consistent with the technical requirements of the metrological verification procedures or calibration specifications;

[0079] Step S7. According to the technical requirements of the metrological verification procedure or calibration specification, the diffusion alarm is calibrated and calibrated using the zero-point standard gas and toxic acid standard gases of different concentrations through the calibration gas circuit.

[0080] The working principle of the calibration device in this embodiment:

[0081] 1) After the standard gas in the standard gas cylinder 1 is adjusted in flow by the pressure reducing valve 2 with flow meter, the gas line tee 3 and the flow meter 5, the alarm sensor is purged through the sealed calibration cover 4. The sealed calibration cover 4 is sealed and connected to the sensor housing of the fixed diffusion alarm through an elastic adapter sleeve, and then reinforced with a fastening ring; the toxic acidic standard gas enters the sealed calibration cover 4 through the calibration cover air inlet pipe to purge the sensor; during the purging process, the metrological technicians calibrate the alarm according to the technical requirements of the metrological verification procedures or calibration specifications; during the whole process, no toxic acidic gas leaks through the sealed calibration cover 4.

[0082] 2) The tail gas is purged or the bypass gas through the flow meter 5 enters the anti-backflow scrubber 6. The alkali in the alkali storage container converts the toxic acidic standard gas into a salt derivative that can be recycled or treated to reduce toxicity through an acid-base reaction; the porous partition can prevent the alkali from shaking, colliding and splashing, and impacting the top of the alkali storage container. The tail gas after the acid-base reaction can overflow from the small holes on the partition; the concentration of the toxic acidic standard gas is at the ppm level, and the content of the toxic acidic gas is very low, generally in the range of (10 to 100) ppm. Combined with the anti-backflow device with a thick middle and thin ends, the backflow of the alkali in When passing through the anti-backflow device, it can use its own gravity to prevent further backflow; the gas dispersion device adopts a seven-way structure to disperse the gas entering from the anti-backflow device into 6 parts, and generates small bubbles through the aeration device evenly dispersed at the bottom of the alkali solution storage container, so as to fully react with the alkali solution with acid and base; the aeration device can use a stainless steel mesh or a polytetrafluoroethylene mesh joint; when not in working state, close the switches of the calibration gas inlet pipe, the bypass gas inlet pipe, the container outlet pipe, the alkali solution inlet pipe and the alkali solution outlet pipe to prevent alkali solution leakage.

[0083] 3) After the purge tail gas flows out of the container outlet pipe of the anti-backflow scrubber 6, it passes through the temperature and humidity monitor 8. If the sound and light alarm component of the temperature and humidity monitor 8 issues a physical sound and light warning, it means that the water-absorbing material is saturated with water or the tail gas temperature is too high, and the temperature and humidity exceed the valve limit of the normal working temperature and humidity of the toxic gas residue monitor 9; at this time, the calibration work is stopped immediately, and the entire calibration gas path and bypass gas path are purged with zero-point standard gas to remove residual toxic acidic gases, and then the water-absorbing material is replaced or the temperature is purged for a long time to ensure the accuracy of the detection value of the toxic gas residue monitor 9; the water-absorbing material can be selected from molecular sieves, activated alumina, and silica gel particles, which can be reused after drying to reduce the use cost.

[0084] 4) The tail gas is purged from the temperature and humidity monitor 8 to the toxic gas residue monitor 9, and then directly discharged into the ambient air after passing through the toxic gas residue monitor 9. If the sound and light alarm component of the toxic gas residue monitor 9 emits a physical sound and light warning, it means that the effect of the alkali solution in converting toxic acidic gases through acid-base reaction has decreased, the concentration of the alkali solution has decreased, and the concentration of toxic acidic gases in the tail gas has exceeded the concentration threshold limit of toxic acidic gas emissions; at this time, the calibration work is immediately stopped, and the entire calibration gas path and bypass gas path are purged with zero-point standard gas to remove residual toxic acidic gases, and then the waste alkali solution in the alkali solution storage container is released and new alkali solution is added; the conversion effect of toxic acidic gases is ensured to avoid toxic acidic gases from polluting the environment and possible harm to the health of metrological technicians.

Claims

1. A calibration device for a toxic acid gas alarm, comprising a housing and a cover, characterized in that: 1) A standard gas cylinder (1), a pressure reducing valve with a flow meter (2), a gas line tee (3), and a sealed calibration cover (4) are arranged outside the shell, and a flow meter (5), an anti-backflow gas washing device (6), a gas dryer (7), a temperature and humidity monitor (8), and a poisonous gas residue monitor (9) are arranged inside the shell. 2) A pressure reducing valve with a flow meter (2), a gas line tee (3), a sealed calibration cover (4), an anti-backflow gas washing device (6), a gas dryer (7), a temperature and humidity monitor (8) and a toxic gas residue monitor (9) are connected in sequence through a gas pipeline to form a calibration gas line of the calibration device. 3) A pressure reducing valve with a flow meter (2), a gas line tee (3), a flow meter (5), an anti-backflow gas washing device (6), a gas dryer (7), a temperature and humidity monitor (8) and a toxic gas residue monitor (9) are connected in sequence through a gas pipeline to form a bypass gas path of the calibration device.

2. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The calibration object of the calibration device is a poisonous acid gas alarm for detecting trace gases of hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide.

3. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The standard gas cylinder (1) can be replaced with a cylinder with the same interface; the cylinder with the same interface stores zero-point standard gas and toxic acidic standard gases of different types and concentrations respectively; the zero-point standard gas is pure nitrogen standard gas; the toxic acidic standard gases of different types and concentrations are standard gases of different concentrations of hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, chlorine and sulfur dioxide.

4. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The sealing calibration cover (4) is composed of an elastic adapter sleeve, a fastening ring and a cylindrical cover; the two ends of the elastic adapter sleeve have different apertures, the end with a larger aperture is connected to the cylindrical cover; the end with a smaller aperture is connected to the sensor housing of the alarm; the fastening ring is made of metal and has a fastening screw and a fastening knob; the bottom end of the cylindrical cover is provided with a calibration cover air inlet pipe and a calibration cover air outlet pipe; the calibration cover air inlet pipe is located in the middle of the bottom of the cylindrical cover and is connected to the air circuit tee (3); the calibration cover air outlet pipe is located beside the bottom of the cylindrical cover and is connected to the anti-backflow washing device (6).

5. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The anti-backflow scrubbing device (6) is composed of an alkali solution storage container, a porous partition, an anti-backflow device, a gas dispersion device and an aeration device; the alkali solution storage container is filled with alkali solution, and a calibration gas path air inlet pipe, a bypass gas path air inlet pipe, a container air outlet pipe and an alkali solution inlet pipe are arranged at the top, and an alkali solution outlet pipe is arranged at the side; the front end of the calibration gas path air inlet pipe is connected to a sealed calibration cover (4), and the end is connected to the anti-backflow device; the front end of the bypass gas path air inlet pipe is connected to a flow meter (5), and the end is connected to the anti-backflow device; the porous partition is arranged horizontally above the alkali solution in the alkali solution storage container, and the surface The anti-backflow device is a cylindrical cavity with openings at both ends, the upper opening is connected to the calibration gas path air inlet pipe and the bypass gas path air inlet pipe, and the lower opening is connected to the gas dispersion device; the gas dispersion device is a gas path multi-channel structure, which is a device with an air inlet and multiple air outlets, the air inlet is connected to the anti-backflow device, and the air outlet is connected to the aeration device; the aeration device is a fine-pore joint; the container air outlet pipe is connected to the gas dryer (7); the calibration gas path air inlet pipe, the bypass gas path air inlet pipe, the container air outlet pipe, the alkali solution inlet pipe and the alkali solution outlet pipe are all provided with switches.

6. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The gas dryer (7) is a cylindrical cavity, with a dryer air inlet pipe and a dryer air outlet pipe provided at both ends of the cavity; the cylindrical cavity is filled with water-absorbing material; the dryer air inlet pipe is connected to an anti-backflow washing device (6); and the dryer air outlet pipe is connected to a temperature and humidity monitor (8).

7. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The temperature and humidity monitor (8) is provided with a temperature and humidity sensor, a numerical display component and an audible and visual alarm component, and an alarm value can be set; the temperature and humidity sensor is built into the gas path cavity; the gas path cavity is a cylindrical cavity, and a cavity air inlet pipe and a cavity air outlet pipe are provided at both ends of the cavity, the cavity air inlet pipe is connected to the gas dryer (7), and the cavity air outlet pipe is connected to the toxic gas residue monitor (9).

8. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The poison gas residue monitor (9) is provided with a plurality of sensor components, a numerical display component and an audible and visual alarm component, and alarm values ​​can be set; the plurality of sensor components are provided with a sealed housing, and are sensor components for detecting hydrogen sulfide, hydrogen fluoride, hydrogen cyanide, hydrogen chloride, sulfur dioxide and chlorine respectively; the sealed housing is provided with a housing air inlet pipe and a housing air outlet pipe, the housing air inlet pipe is connected to the temperature and humidity monitor (8), and the housing air outlet pipe is directly connected to the ambient air.

9. The calibration device for a toxic acid gas alarm according to claim 1, characterized in that: The cover body includes a side cover body and a top cover body, and the side cover body and the top cover body are connected by a lock; the side cover body is located on the side of the shell and is connected to the bottom of the shell through a connecting shaft; the top cover body is located at the top of the shell and is connected to the side of the shell through a connecting shaft.

10. The calibration method for calibrating a toxic acid gas alarm using a calibration device according to any one of claims 1 to 9, characterized in that: The calibration objects and steps are as follows: 1) Calibrate the self-priming alarm: Step S1. Select a sensor assembly corresponding to the toxic acidic standard gas for calibration and install it on the toxic gas residue monitor (9); Step S2. Setting the alarm values ​​of the temperature and humidity monitor (8) and the residual gas monitor (9); Step S3. Adding alkali solution into the anti-backflow scrubber (6); Step S4. Connect the self-priming alarm to the sealed calibration cover (4); Step S5. Turn on the switch of the flow meter (5) to clear the bypass air path; Step S6. Open the valve of the standard gas cylinder (1), and adjust the difference between the flow rate of the pressure reducing valve (2) with a flow meter and the flow rate of the flow meter (5) to be equal to the pump suction flow rate of the self-priming alarm; Step S7. According to the technical requirements of the metrological verification procedure or calibration specification, the self-priming alarm is calibrated and calibrated using the zero-point standard gas and toxic acid standard gases of different concentrations through the calibration gas circuit and the bypass gas circuit. 2) Calibrate the diffusion alarm: Step S1. Select a sensor assembly corresponding to the toxic acidic standard gas for calibration and install it on the toxic gas residue monitor (9); Step S2. Setting the alarm values ​​of the temperature and humidity monitor (8) and the residual gas monitor (9); Step S3. Adding alkali solution into the anti-backflow scrubber (6); Step S4. Connecting the diffusion alarm to the sealed calibration cover (4); Step S5. Turn off the switch of the flow meter (5) to cut off the gas bypass pipeline; Step S6. Open the valve of the standard gas cylinder (1), and adjust the flow rate of the pressure reducing valve (2) with a flow meter to be consistent with the instructions of the alarm. If the instructions do not have clear requirements for the flow rate, it shall be consistent with the technical requirements of the metrological verification procedures or calibration specifications; Step S7. According to the technical requirements of the metrological verification procedure or calibration specification, the diffusion alarm is calibrated and calibrated using the zero-point standard gas and toxic acid standard gases of different concentrations through the calibration gas circuit.

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