Device for detecting flammable gas release rate of chemical substance when meeting water

Abstract

The invention discloses a device for detecting the flammable gas release rate of a chemical substance when meeting water, and belongs to the field of dangerous chemical identification classification and safety management, the main body structure of the detection device is a constant temperature box body, and the whole constant temperature box body is integrally formed by processing stainless steel; two reaction containers are designed in a cavity of the constant-temperature box body, one reaction container is a test reaction container used for actually testing a sample, and the other reaction container is a reference reaction container used for blank control to eliminate environmental signal interference. According to the invention, the whole reaction container is arranged in a constant temperature box, so that the temperature of the whole system is controlled at 20 DEG C, and the result error caused by the fluctuation of the volume of gas discharged by a test sample when the outside air temperature is changed is avoided. According to the invention, the reference test container is additionally arranged, and the micro-differential pressure sensor is used, so that the influence of external atmospheric pressure change on the detected gas release rate is avoided to the greatest extent, and the test result is high in accuracy.

Description

Technical Field

[0001] The invention belongs to the field of identification, classification and safety management of hazardous chemicals, and in particular relates to a device for detecting the rate at which a chemical substance releases flammable gas when in contact with water. Background Art

[0002] When certain substances in chemicals come into contact with water, they may react and release gases. These gases may form explosive compounds when mixed with air and are easily ignited and exploded. The resulting shock waves and flames may cause harm to operators and the surrounding environment. In order to ensure the safety of dangerous goods during transportation, dangerous goods must be correctly classified according to the international dangerous goods regulations before packaging, and appropriate packaging categories must be selected according to their hazard classification. In recent years, there have been many safety accidents caused by incorrect classification of dangerous goods, resulting in incorrect selection of packaging categories.

[0003] The main basis for testing substances that release flammable gases when in contact with water in the field of identification, classification and safety management of hazardous chemicals is the United Nations Manual of Tests and Criteria 33.5.4 Test N.5: Test Methods for Substances that Release Flammable Gases When in Contact with Water, referred to as the Standard Manual. The Standard Manual sets up preliminary tests, filter paper tests, stacking tests and gas volume measurement tests per unit time for hazardous substances that can release flammable gases when in contact with water. The first three tests are relatively simple and do not require specific test equipment. They are aimed at substances that can react with water to release gases that can spontaneously combust in the air. For the remaining substances that release a large amount of flammable but non-self-igniting gases when in contact with water, the maximum rate of gas generation is used as the basis for hazard classification.

[0004] Such equipment and existing technologies on the market usually have the following three disadvantages: First, the temperature control part only controls the temperature of the reaction container part, and does not control the temperature of the entire system. According to PV=nRT, when the temperature changes by 1°C, the volume change of 1 mol of gas is about 82mL. Therefore, if there are no strict temperature control measures, when the outside temperature changes, the volume of gas released by the test sample will fluctuate, causing error in the results, and seriously affecting the classification level of dangerous goods. Second, some specific samples will react violently with water, releasing a large amount of heat and generating a large amount of water vapor. This part of water vapor may first condense in the pipeline and flow back into the reaction container, seriously affecting the accuracy of the test results. Secondly, during long-term use, more or less corrosive substances will enter the instrument along with water vapor, causing corrosion damage to the instrument. Third, the equipment currently used to detect the rate at which a substance releases flammable gases when in contact with water mainly uses the water displacement method or the gas flow rate method. The gas volume is calculated by the volume of water or the gas flow rate, which results in large errors. Furthermore, because the "Standard Manual" requires that the test be conducted for at least seven hours, the test results are easily affected by changes in external atmospheric pressure, making it almost impossible to accurately collect and detect the volume of the gas. Summary of the invention

[0005] In order to solve the above problems, the present invention proposes a detection device for the rate at which a chemical substance releases flammable gas when in contact with water, which is used to accurately evaluate the risk level of the tested chemical substance in terms of releasing flammable gas when in contact with water.

[0006] The technical solution of the present invention is as follows:

[0007] A detection device for the rate at which a chemical substance releases flammable gas when in contact with water, wherein the main structure of the detection device is a constant temperature box, and the entire constant temperature box is integrally formed by processing with stainless steel;

[0008] The entire detection device can be divided into three parts: upper, middle and lower parts, which are: data processing and display part, detection and signal collection part, and detection temperature control part. The relevant components in the three parts are connected through signal control lines and power lines;

[0009] The detection temperature control part is used to ensure that the test substance is controlled to react with water at an ambient temperature of 20°C, and maintain stable cooling and heating of the constant temperature box, including a heater, a compressor, an adjustable air outlet, an air inlet in the constant temperature box, a circulating fan, a compressor storage tank, a connecting pipe, and an exhaust pipe of the temperature control system;

[0010] The detection and signal collection part consists of two reaction containers with lids on the top, one of which is a test reaction container for the actual test sample, and the other is a reference reaction container for blank control to eliminate environmental signal interference;

[0011] The data processing and display part is used for setting relevant parameters in the detection process and processing and displaying relevant detection data, including equipment switches and touch screens.

[0012] Furthermore, the touch screen is internally connected to an embedded intelligent processor, which adopts Panasonic GT32-E programmable intelligent operation panel, and uses its own Terminal GTWIN operation language to program, design and develop special detection software; after the test starts, the embedded intelligent processor continuously collects the real-time changes of pressure in the test reaction container and the reference reaction container through the data port, and obtains the increase in gas volume corresponding to the pressure change through analysis and calculation by the special detection software, and displays the cumulative volume of released gas and the release rate-time trend chart on the touch screen.

[0013] Furthermore, the detection-specific software consists of five modules, namely: a sample information input module, a test condition setting module, a real-time detection module, a data management module, and a data analysis module; wherein the sample information input module is used to input the information of the corresponding substance that the tester needs to detect, including the name, chemical formula, and sample number; the test condition setting module is used for the tester to set the test conditions according to the specific situation, including temperature, sample addition mass, and test time; the real-time detection module is used to collect data that needs to be monitored in real time, including gas release volume, gas release speed, and test duration; the data management module is used for the tester to view historical test data or manage saved data; the data analysis module is used to provide charts and reports.

[0014] Furthermore, the detection software automatically calculates the release rate and the cumulative gas release once every hour, and saves them in the test table; the detection software can obtain the current deflation rate, current deflation volume, maximum deflation rate and test time, and automatically analyze the test results according to the set test parameters to determine the hazard category.

[0015] Furthermore, the device switch and the touch screen are both embedded in the constant temperature box.

[0016] Furthermore, a cavity is provided in the middle of the thermostatic box, and two grooves are reserved in the bottom surface of the cavity, a reaction bottle is placed in each groove, and each reaction bottle is covered with a sealing cover, and the groove of the sealing cover is embedded with a sealing rubber ring, and the sealing cover is thread-sealed and connected with the reaction bottle through the sealing rubber ring;

[0017] One of the sealing covers is used as a test sealing cover, and the other sealing cover is used as a reference sealing cover; the test sealing cover and the reaction bottle constitute a test reaction container; the reference sealing cover and the reaction bottle constitute a reference reaction container;

[0018] The test sealing cover is divided into an upper and lower cover structure, and the two covers are connected by threads; the outer surface of the upper cover of the test sealing cover is embedded with a micro pressure sensor, and two through holes are opened at the same time, a stainless steel air pipe is buried in one through hole, and a temperature sensor is buried in the other through hole, the stainless steel air pipe and the temperature sensor are both extended into the glass reaction bottle through the through hole of the sealing cover, the stainless steel air pipe connects the inside and outside of the reaction container and the micro pressure sensor, and the upper cover is equipped with a data line and a power line connecting the temperature sensor and the micro pressure sensor; the lower cover body of the test sealing cover is a measuring cup, which is threadedly connected to the upper cover through a connecting part, a vent is left at the bottom of the connecting part, and a circular hole for controlling the opening and closing of an electromagnetic valve is left at the bottom of the measuring cup, and the data transmission line of the electromagnetic valve is connected to the sealing cover through a waterproof quick plug connector and connected to the data transmission line;

[0019] The reference sealing cover only has an upper cover structure, which is also connected with a micro pressure sensor, a stainless steel air pipe, and a temperature sensor, but does not have a measuring cup and its related connection lines.

[0020] There is a vent on each of the left and right sides of the thermostatic box, which is connected to the outside and is controlled by a solenoid valve. The vent is connected to one end of the dryer through a hose, and the other end of the dryer is connected to a stainless steel air pipe through a hose.

[0021] A waterproof power socket is provided on each of the side walls on both sides of the cavity;

[0022] A constant temperature box door is arranged on the front of the constant temperature box body.

[0023] Furthermore, the cavity volume is set to 50L; the reaction bottle is made of high borosilicate glass with a volume of 600mL; the sealing cover is made of polytetrafluoroethylene supplemented with stainless steel; the hose is made of transparent polytetrafluoroethylene material and can be removed from the connection; the measuring cup is made of polytetrafluoroethylene material with a volume of 250mL, with a scale mark at 200mL and a liquid level sensor; the circular hole at the bottom of the measuring cup is 0.8cm, and the circular hole is initially sealed with a solenoid valve. When the power is not turned on, the circular hole is closed and watertight. After the power is turned on, the solenoid valve opens to allow the substance in the measuring cup to slowly flow into the reaction bottle; the thermostat door adopts a double-door structure with double-layer sealing, the outer door is sealed and opened with a magnetic rubber strip, the inner door is an oversized tempered glass door, and the glass door and the box body are sealed with a silicone strip.

[0024] Furthermore, the lower part of the constant temperature box is also an internal cavity structure, in which a heater and a compressor are arranged, and the heater and the compressor are connected by a connecting pipe; a circulating fan is connected above the heater, and an adjustable air outlet is connected above the circulating fan; a compressor liquid storage tank is also connected above the compressor, and an air inlet in the constant temperature box is connected above the compressor liquid storage tank; a temperature control system exhaust pipe is also connected between the compressor and the inner wall of the box.

[0025] Furthermore, each of the four corners of the outer bottom surface of the thermostatic box is provided with a universal wheel for facilitating the overall movement of the device; and a lighting lamp is also provided inside the thermostatic box.

[0026] Furthermore, the detection process of the detection device is as follows:

[0027] Step 1: Sample pretreatment;

[0028] Step 1.1: For solid substances, check whether there are any particles with a diameter of less than 500 microns in the package. If such powder accounts for more than 1% of the total mass of the substance, or the substance is friable, grind the entire sample into powder before testing;

[0029] Step 1.2: Perform a preliminary screening test on the substance to be tested according to the following steps. If spontaneous combustion occurs at any of the following stages, no further testing is required;

[0030] Step 1.2.1. Place a small amount of the test substance in a sink containing 20°C distilled water;

[0031] Step 1.2.2: Place a small amount of the test substance at the center of a piece of filter paper floating flat on the surface of 20°C distilled water in a suitable container;

[0032] Step 1.2.3, make a pile of the test substance with a height of about 20 mm and a diameter of about 30 mm, make a groove on the top of the pile, and add a few drops of water into the groove;

[0033] Step 2: Perform the test according to the following process;

[0034] Step 2.1, during the test, the test reaction container is added with the sample for testing, and the reference reaction container is not added with the sample but only with 200 ml of distilled water as a control reference;

[0035] Step 2.2, turn on the power of the equipment, open the thermostat, unplug the line quick plug connectors and dryers on each reaction container, and take out the two reaction containers;

[0036] Step 2.3, weigh the sample to be tested using a balance. The sample mass cannot exceed 25 grams;

[0037] Step 2.4, unscrew the test sealing cover, add up to 25g of the substance to be tested into the reaction bottle; unscrew the polytetrafluoroethylene measuring cup under the sealing cover, add 200ml of distilled water into it, and then screw it back into the lower layer of the sealing cover; put the test sealing cover on the reaction bottle containing the sample and tighten it to make it sealed;

[0038] Step 2.5, unscrew the reference sealing cap, add 200 mL of distilled water to the reaction bottle, and then install the reference sealing cap on the reaction bottle and tighten it to make it sealed;

[0039] Step 2.6, place the two sealed reaction bottles into the grooves on the bottom of the cavity of the constant temperature box and fix them, connect the dryer and the quick-connect connector, and then close the door of the constant temperature box;

[0040] Step 2.7, open the detection software, select the corresponding connection port, and set the water bath temperature to 20℃;

[0041] Step 2.8, enter the sample number, sample material and customer object information in the corresponding interface of the detection software, set the file storage path, click the start button and automatically balance, after the temperature in the reaction bottle stabilizes at 20°C, the solenoid valve opens, the water in the test reaction container begins to flow down slowly, and the device automatically starts testing;

[0042] Step 2.9: After the test, save the test data, turn off the equipment, disassemble and clean the reaction bottle and dry it;

[0043] Step 3: Determine the test results;

[0044] Step 3.1. Substances meeting the following conditions are classified as hazard types: in contact with water, they emit flammable gases: spontaneous combustion occurs at any step of the test procedure, or the rate of release of flammable gases is greater than 1 litre per kilogram of substance per hour;

[0045] Step 3.2: Materials that meet the following conditions are classified in Packing Group I / Category 1: They react violently with water at ambient temperature and the gases produced usually show a tendency to spontaneous combustion, or they react readily with water at ambient temperature and release flammable gases at a rate greater than or equal to 10 litres per kilogram of material in any one minute;

[0046] Step 3.3: Materials that meet the following conditions are classified in Packing Group II / Category 2: They react readily with water at ambient temperature, release flammable gases at a maximum rate greater than or equal to 20 litres per kilogram of material per hour, and do not meet the criteria for Packing Group I / Category 1;

[0047] Step 3.4: Materials that meet the following conditions are classified in Packing Group III / Category 3: They react slowly with water at ambient temperature, the maximum rate of release of flammable gas is greater than 1 litre per kilogram of material per hour, and do not meet the criteria for Packing Groups I and II / Categories 1 and 2.

[0048] Beneficial technical effects brought by the present invention:

[0049] The present invention designs a new device for detecting the rate of flammable gas released when in contact with water in accordance with the relevant requirements of the United Nations Recommendations on the Transport of Dangerous Goods. A micro-pressure difference sensing method is used to replace the existing drainage method and flow rate measurement method to calculate the release rate of flammable gas. Through the setting of a reference reaction container, the connection of a drying tube and strict temperature control measures, three common problems of similar equipment on the market are solved, and accurate measurement of the rate of flammable gas released when a substance reacts with water is achieved. The entire device has a compact structure, and all components are integrated into a constant temperature box, which is easy to move and carry. The entire device can be placed in a fume hood to avoid possible harm to the experimenters caused by the generated gas. Glass containers or corrosion-resistant polytetrafluoroethylene hoses are used as much as possible to connect the containers in the reaction system, which not only improves the accuracy of the test data, but also extends the service life of the experimental device.

[0050] The present invention is mainly used in the field of identification, classification and safety management of hazardous chemicals to test the rate of flammable gas released by substances in water. A highly modularized and integrated high-precision detection device for the rate of flammable gas released in water has been developed to determine the hazard of gas released by substances in water reaction, automatically determine the applicable transport hazard category of the substances, and is applicable to the identification and appraisal of the hazard of substances that release flammable gas in water as specified in the United Nations Recommendations on the Transport of Dangerous Goods.

[0051] This invention proposes an effective solution to the three major problems commonly found in similar equipment currently used in the industry: the difficulty in accurately controlling the reaction temperature, the inability to avoid the negative impact of water vapor generated during the test, and the test results being easily affected by changes in atmospheric pressure. All components of the device can be integrated into a portable constant temperature box, which is easy to use, highly automated, and has high detection accuracy. It can achieve full-process real-time monitoring of the gas rate generated by the test substance during the water reaction. It not only has broad application prospects in the commercial field of hazardous chemical identification, but also has obvious demand for this patent from scientific research institutions that study the release of gas by substances in water reactions. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a front structural diagram of a device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to the present invention;

[0053] Figure 2 for Figure 1 A front view of a reaction vessel consisting of a test sealing cover and a glass reaction bottle;

[0054] Figure 3 for Figure 1 A top view of the upper portion of the middle sealing cover;

[0055] Figure 4 for Figure 1 The front structure diagram without the sealing cover and the glass reaction bottle;

[0056] Among them, 1-equipment switch; 2-touch screen; 3-dryer; 4-vent; 5-test sealing cover; 6-reference sealing cover; 7-constant temperature box door; 8-constant temperature box; 9-reaction bottle; 10-data transmission line; 11-heater; 12-compressor; 13-universal wheel; 14-micro pressure sensor; 15-quick plug connector; 16-stainless steel air pipe; 17-temperature sensor; 18-connecting part; 19-vent; 20-measuring cup; 21-solenoid valve; 22-waterproof power socket; 23-adjustable air outlet; 24-air inlet in the constant temperature box; 25-circulating fan; 26-compressor liquid storage tank; 27-connecting pipe; 28-temperature control system exhaust pipe. DETAILED DESCRIPTION

[0057] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0058] like Figures 1 to 4 As shown, the present invention proposes a detection device for the rate of flammable gas released by chemical substances when in contact with water. The main structure of the detection device is a constant temperature box 8, and the entire constant temperature box 8 is made of stainless steel and is integrally formed. The entire detection device can be divided into three parts, namely: a data processing and display part, a detection and signal collection part, and a detection temperature control part. The relevant components in the three parts are connected through signal control lines and power lines and cooperate with each other.

[0059] The core function of the detection temperature control part is to ensure that the test substance is controlled to react with water at an ambient temperature of 20°C. The detection temperature control part mainly includes a heater 11, a compressor 12, an adjustable air outlet 23, an air inlet 24 in a constant temperature box, a circulating fan 25, a compressor liquid storage tank 26, a connecting pipe 27, a temperature control system exhaust pipe 28 and other conventional refrigeration cycle devices. The connection of the above components can ensure stable cooling and heating of the constant temperature box 8.

[0060] The detection and signal collection part is mainly composed of two special cylindrical reaction containers with covers on the top. One reaction container is a test reaction container for actual test samples, and the other is a reference reaction container for blank control to eliminate environmental signal interference. The reaction containers are composed of a sealing cover and a reaction bottle. The detection and signal collection part mainly includes a dryer 3, a vent 4, a test sealing cover 5, a reference sealing cover 6, a constant temperature box door 7, a glass reaction bottle 9, a data transmission line 10, a micro pressure sensor 14, a quick connector 15, a stainless steel air pipe 16, a temperature sensor 17, a connection part 18, a vent 19, a measuring cup 20, a solenoid valve 21, and a waterproof power socket 22.

[0061] The data processing and display part is used for setting relevant parameters in the detection process and processing and displaying relevant detection data, mainly including equipment switch 1 and touch screen 2. The touch screen 2 is internally connected to an embedded intelligent processor, using the Panasonic GT32-E programmable intelligent operation panel, and using its own Terminal GTWIN operation language for programming, designing and developing the detection-specific software. Its main working principle is to use the gas micro-pressure sensor to detect the pressure changes in the test reaction bottle and the reference reaction bottle in real time, and output the digital signal to the intelligent processor through the signal conditioning and analog-to-digital conversion circuit. The intelligent processor obtains the real-time pressure signal comparison in the two reaction bottles. According to the change of the pressure difference between the two reaction bottles, the ideal gas state equation PV=nRT (P represents the pressure of the ideal gas, V represents the volume of the ideal gas, n represents the amount of gas substance, R is the ideal gas constant, and T represents the thermodynamic temperature of the ideal gas) is used to calculate the gas volume generated every 10 seconds in the test reaction bottle. After further visualization processing by the compiled detection-specific software, the cumulative volume of the released gas (accurate to 0.01ml) and the release rate-time trend chart are displayed on the display. The volume L (ml) of the gas released by the reaction, the speed v (ml / s) of the gas released by the reaction and the reaction time t (s) have the following relationship: L = v·t, and the total amount of the generated gas can be obtained.

[0062] The detection software is mainly composed of 5 modules, namely: sample information input module, test condition setting module, real-time detection module, data management module, and data analysis module. Among them, the sample information input module is used to input the information of the corresponding substance that the tester needs to detect, including name, chemical formula, sample number, etc. The test condition setting module is used for the tester to set the test conditions according to the specific situation, including temperature, sample addition mass, test time, etc. The real-time detection module is used to collect data that needs to be monitored in real time, including gas release volume, gas release rate, test time duration and other data. This module provides a visual monitoring interface and monitoring data. The data management module is used for testers to view historical test data or manage saved data, including deleted and exported data. The data analysis module is used to provide charts and reports to facilitate data visualization and analysis.

[0063] After the test begins, the embedded intelligent processor continuously collects the real-time changes in the pressure in the test reaction container and the reference reaction container through the data port, and obtains the gas volume increase corresponding to the pressure change through analysis and calculation by the dedicated detection software, and displays the cumulative volume of the released gas (accurate to 0.01ml) and the release rate-time trend chart on the touch screen 2.

[0064] The detection software automatically calculates the release rate and cumulative gas release once an hour and saves them in the test table. The detection software can obtain the current gas release rate, current gas release volume, maximum gas release rate and test time, and can automatically analyze the test results according to the set test parameters to determine the hazard category. The detection instrument and the detection process can also be remotely controlled by a computer via a data cable, which greatly facilitates the safety supervision of the production and transportation of substances that release flammable gases when in contact with water.

[0065] The following describes the related connection relationships of the components in each part:

[0066] The device switch 1 and the touch screen 2 are both embedded in the constant temperature box 8 and are located at the upper front side of the constant temperature box 8 .

[0067] The middle position of the thermostatic box 8 is provided with a cavity with a volume of about 50L, and two grooves are reserved on the bottom surface of the cavity. A glass reaction bottle 9 with a volume of about 600mL made of high borosilicate glass is placed in each groove. A sealing cover made of polytetrafluoroethylene supplemented with stainless steel is covered on the top of each glass reaction bottle 9, and the sealing cover is connected with the glass reaction bottle thread seal. One of the sealing covers is used as a test sealing cover 5, and the other sealing cover is used as a reference sealing cover 6. The test sealing cover 5 and the glass reaction bottle 9 constitute a test reaction container for actual test samples, and the reference sealing cover 6 and the glass reaction bottle 9 constitute a reference reaction container for blank control to eliminate environmental signal interference. The inner side wall of the sealing cover is provided with an internal thread, and the bottle mouth position of the glass reaction bottle 9 is provided with an external thread matching the internal thread. The sealing rubber ring is located at the spiral sealing connection between the sealing cover and the glass reaction bottle 9, and is embedded in the groove of the sealing cover. The sealing rubber ring can ensure the sealing effect of the glass reaction bottle. The test sealing cover 5 and the reference sealing cover 6 are both tightly connected to the glass reaction bottle 9 through a threaded structure.

[0068] The left and right sides of the thermostatic box 8 are each provided with a vent 4 controlled by a solenoid valve. The vent 4 is located at the upper position and communicates with the outside. The vent 4 is connected to one end of the dryer 3 through a section of a polytetrafluoroethylene transparent hose, and the other end of the dryer 3 is connected to the stainless steel air pipe 16 through a section of a polytetrafluoroethylene transparent hose. The polytetrafluoroethylene transparent hose can be removed from the connection.

[0069] like Figure 1As shown, the test sealing cover 5 on the left side is divided into an upper and lower cover structure, and the two covers are connected by threads. The upper cover of the test sealing cover 5 is equipped with a temperature sensor and a micro pressure sensor and corresponding data lines and power lines. A 4-point stainless steel air pipe 16 is buried inside the upper cover to connect the inside and outside of the reaction container and the micro pressure difference sensor 14, which can monitor the changes in the gas pressure inside the reaction container in real time. The main body of the lower cover of the test sealing cover 5 is a special polytetrafluoroethylene measuring cup 20 with a content of about 250mL, with a scale mark at 200mL and a liquid level sensor. The solenoid valve 21 installed on the lower cover is connected to the upper cover by a waterproof quick-plug connector 15. The reference sealing cover on the right has only an upper structure and only includes an upper cover. At the beginning of the test, the gas generated in the glass reaction container first enters the drying tube 3 through the 4-point stainless steel air pipe 16, and then is discharged into the atmosphere through the vent 4 of the thermostat.

[0070] The detailed connection structure of the test sealing cover 5 and the reference sealing cover 6 is as follows: a micro pressure sensor 14 is embedded in the central position of the outer surface of the test sealing cover 5 and the reference sealing cover 6, and the micro pressure sensor 14 protrudes from the outer surface of the sealing cover. The micro pressure sensor 14 is used to detect the pressure change in the glass reaction bottle 9 through the pipeline. There are also two through holes on the sealing cover, one through hole is used to accommodate the stainless steel air pipe 16, and the other through hole is used to accommodate the temperature sensor 17. The stainless steel air pipe 16 and the temperature sensor 17 are both extended into the glass reaction bottle 9 through the through hole of the sealing cover. The stainless steel air pipe 16 and the temperature sensor 17 are sealed and connected to the through hole to ensure that no gas leaks, so as to ensure that after the entire reaction container is sealed, the gas generated by the test can only be discharged through the stainless steel air pipe 16. The temperature sensor 17 is used to detect the temperature change in the reaction bottle. The sealing cover is equipped with a temperature sensor and a micro pressure difference sensor and corresponding data lines and power lines.

[0071] In the present invention, only a polytetrafluoroethylene measuring cup 20 with scale lines and a capacity of more than 200 mL is threadedly connected below the test sealing cover 5. Specifically, a connecting portion 18 with an external thread is connected below the test sealing cover 5, and the measuring cup 20 is provided with an internal thread matching the external thread of the connecting portion 18. A vent 19 is left at the bottom of the connecting portion 18, and the vent 19 can ensure that the gas in the measuring cup 20 and the glass reaction bottle 9 can flow normally. A circular hole with a diameter of 0.8 cm is left at the center of the bottom of the measuring cup 20, and the opening and closing of the circular hole is controlled by a solenoid valve. The circular hole is sealed with a water-blocking solenoid valve 21. When the power is not turned on, the circular hole is closed and watertight. After the power is turned on, the water-blocking solenoid valve 21 is opened to allow the distilled water in the measuring cup 20 to slowly flow into the glass reaction bottle 9. The data transmission line of the water-blocking solenoid valve 21 is connected to the sealing cover through a waterproof quick-plug connector 15, and then connected to the data transmission line 10. The reference sealing cover as a blank reference is not provided with a measuring cup 20, a connecting part 18, etc. and related connecting line structures. A connected data transmission line 10 is buried in the side wall of the constant temperature box 8, and the data transmission line 10 is connected to an external power supply. The micro pressure sensor 14 and the temperature sensor 17 on the test sealing cover 5 and the reference sealing cover 6 are connected to the data transmission line 10 through a waterproof quick plug connector 15.

[0072] A waterproof power socket 22 is provided on each side wall of the cavity, which can be placed at the lower side, and the waterproof power socket 22 is set close to the inner wall of the box. A thermostatic box door 7 is provided on the front of the thermostatic box 8. The thermostatic box door 7 on the front of the box adopts a double-door structure with double-layer sealing, the outer door is sealed and opened with a magnetic rubber strip, and the inner door is an oversized tempered glass door, and the glass door and the box are sealed with a silicone strip.

[0073] The lower part of the constant temperature box 8 is also an internal cavity structure, in which a heater 11 and a compressor 12 are arranged, and the heater 11 and the compressor 12 are connected by a connecting pipe 27; a circulating fan 25 is connected above the heater 11, and an adjustable air outlet 23 is connected above the circulating fan 25; a compressor liquid storage tank 26 is also connected above the compressor 12, and an air inlet 24 in the constant temperature box is connected above the compressor liquid storage tank 26; a temperature control system exhaust pipe 28 is also connected between the compressor 12 and the inner wall of the box.

[0074] The four corners of the outer bottom surface of the thermostatic box 8 are respectively provided with a universal wheel 13 for facilitating the overall movement of the device.

[0075] The interior of the constant temperature box 8 is also provided with an illuminating lamp for convenient observation of the test situation.

[0076] The thermostatic box 8 of the present invention is a single-machine compressor refrigeration, and adopts a refrigeration system of an evaporator and condenser made of pure copper and a heater balanced temperature control. A breeze circulation is also provided in the box to ensure that the temperature in the box is uniform. The temperature control accuracy of the thermostatic box is ±0.5°C, and the uniformity is ±1°C. The equipment is equipped with a waterproof power socket 22, and signal control lines and power lines for accessories such as micro pressure sensors, temperature sensors, and solenoid valves are buried. There are many models of this type of thermostatic box on the market that meet the basic requirements, and you can modify it yourself after purchase without redesigning and customizing.

[0077] The above device is a special detection device that complies with the requirements of "United Nations Manual of Tests and Criteria 33.5.4 Test N.5: Test method for substances that release flammable gases when in contact with water". It is used to test the rate at which solid and liquid substances release flammable gases when in contact with water, and uses the container micro-pressure difference induction method to calculate the release rate of flammable gases.

[0078] The detection device of the present invention places the reaction container as a whole in a constant temperature box so that the temperature of the entire system is controlled at 20°C, and a reference reaction container is set for comparison, thereby avoiding as much as possible the result error caused by fluctuations in the volume of gas released by the test sample when the external temperature changes.

[0079] The present invention installs a dryer outside the reaction container, which solves the problem that part of the samples release heat and generate a large amount of water vapor when they come into contact with water during the test, thus causing adverse effects on the accuracy of the test results and the service life of the equipment.

[0080] In addition to the water-contacting reaction container that is usually possessed by such equipment, the present invention additionally adds a reference test container and uses a micro-pressure difference sensor to avoid the influence of external atmospheric pressure changes on the detected gas release rate to the greatest extent, and the test result is highly accurate.

[0081] The present invention uses dedicated detection software for analysis and calculation to deduct the gas volume fluctuation caused by the change of the air pressure in the reference test container, thereby avoiding the influence of the external atmospheric pressure change on the detected gas release rate to the greatest extent.

[0082] The present invention uses special detection software and a visual touch screen to implement monitoring of test results, and no personnel need to be on standby during the test.

[0083] The test standards that the detection device designed by the present invention complies with are as follows:

[0084] 1. "United Nations Manual of Tests and Criteria 33.5.4 Test N.5: Test method for substances which emit flammable gases in contact with water";

[0085] 2. GB / T 21619-2008 “Test method for flammable gases released by dangerous flammable solids in contact with water”.

[0086] The detection device of the present invention is not suitable for testing pyrophoric substances. The detection process of the detection device of the present invention specifically includes the following steps:

[0087] Step 1: Sample pretreatment;

[0088] Procedure 1.1: For solid substances, check whether there are any particles with a diameter of less than 500 microns in the package. If such powder accounts for more than 1% of the total mass of the substance, or the substance is friable, all samples should be ground into powder before testing to take into account the reduction of particle size during loading, unloading and transportation. Otherwise, the substance should be tested in commercial form as for liquids.

[0089] Step 1.2: The substance to be tested should be subjected to a preliminary screening test according to the following steps. If spontaneous combustion occurs at any of the following stages, no further testing is required. The preliminary screening test is to prevent the test substance from reacting too violently when it comes into contact with water, exceeding the upper limit of the measurement of the detection device of the present invention and damaging the equipment. The test substance that spontaneously combusts at this stage cannot be tested using the detection device of the present invention.

[0090] Step 1.2.1. Place a small amount of the test substance (about 2 mm in diameter) in a sink containing distilled water at 20°C.

[0091] Step 1.2.2: Place a small amount of the test substance (about 2 mm in diameter) at the center of a piece of filter paper floating flat on the surface of 20°C distilled water in a suitable container (such as an evaporating dish with a diameter of 100 mm).

[0092] Step 1.2.3: Make a pile of the test substance with a height of about 20 mm and a diameter of about 30 mm, make a groove on the top of the pile, and add a few drops of water in the groove.

[0093] Step 2: Perform the test according to the following process;

[0094] Step 2.1: During the test, the sample is added to the test reaction container for testing, and no sample is added to the reference reaction container but only 200 ml of distilled water is added as a control reference.

[0095] Step 2.2, turn on the power of the equipment, open the thermostat, unplug the line quick plug connectors and dryers on each reaction container, and take out the two reaction containers;

[0096] Step 2.3, weigh the sample to be tested using a balance. The sample mass cannot exceed 25 grams;

[0097] Step 2.4, unscrew the test seal cap and add up to 25g of the substance to be tested into the reaction bottle. Unscrew the polytetrafluoroethylene measuring cup under the seal cap, add 200ml of distilled water into it and screw it back into the seal cap. Be careful not to let water splash out through the vent during this process. Put the test seal cap on the reaction bottle containing the sample and tighten it to make it sealed.

[0098] Step 2.5, unscrew the reference sealing cap, add 200 mL of distilled water to the reaction bottle, and then install the reference sealing cap on the reaction bottle and tighten it to make it sealed.

[0099] Step 2.6: Place the two sealed reaction bottles into the grooves on the bottom of the thermostat cavity and fix them. After connecting the dryer and quick-connect connector, close the thermostat door.

[0100] Step 2.7. Open the detection software, select the corresponding connection port, and set the water bath temperature to 20°C.

[0101] For example, in the relevant interface of the detection software, set the X-coordinate and Y-coordinate of the real-time flow curve adjustment, where the X-coordinate interval is set to 1, the X-coordinate range is 10, the Y-coordinate spacing is 0.5ml / min, and the Y-coordinate mileage is 30ml / min. Set the connection port of the device information to COM1, the water bath temperature to 20℃, the flow alarm value to 50ml / min, and the time interval to 10 seconds.

[0102] Step 2.8. Enter the sample number, sampling material and customer object information in the corresponding interface of the detection software, set the file storage path, click the start button and automatically balance. After the temperature in the reaction bottle stabilizes at 20°C, the solenoid valve opens, the water in the test reaction container begins to flow slowly, and the device automatically starts testing.

[0103] For example, in the relevant interface, set the sample number to A210115-11-052, the sampling material to ferrosilicon 02, the customer object to the customer name, the file storage path is selected according to the required location, the balance time is set to 30 minutes, and the interface also includes the test start time, running time, cumulative volume and instantaneous flow rate.

[0104] Step 2.9: After the test, save the test data, turn off the equipment switch, disassemble and clean the reaction bottle and dry it.

[0105] Step 3: Determine the test results.

[0106] Step 3.1. Substances that meet the following conditions should be classified into the hazard category of releasing flammable gases in contact with water:

[0107] (a) Spontaneous combustion occurs at any step in the test procedure, or,

[0108] (b) the rate of evolution of flammable gas is greater than 1 litre per kilogram of the substance per hour.

[0109] Step 3.2. Any substance which reacts violently with water at ambient temperature and the gases produced generally show a tendency to spontaneous combustion, or which reacts readily with water at ambient temperature with a maximum rate of release of flammable gases greater than or equal to 10 litres per kilogram of substance in any one minute, should be assigned to Packing Group I / Category 1.

[0110] Step 3.3: Any substance that reacts readily with water at ambient temperature and releases flammable gas at a maximum rate greater than or equal to 20 litres per kilogram of substance per hour and does not meet the criteria for packing group I / category 1 should be classified in packing group II / category 2.

[0111] Step 3.4: Any substance that reacts slowly with water at ambient temperature, releases flammable gas at a maximum rate greater than 1 litre per kilogram of substance per hour, and does not meet the criteria for packing groups I and II / categories 1 and 2, should be assigned to packing group III / category 3.

[0112] In order to demonstrate the feasibility and superiority of the present invention, the following examples are given.

[0113] Example 1: Test on the rate at which calcium powder releases flammable gas when in contact with water.

[0114] Test sample: metallic calcium powder with a median particle size of about 150 μm, a calcium content greater than or equal to 90%, and the rest being impurities such as calcium oxide and calcium hydroxide.

[0115] According to the operation method of step 1 to step 3, the equipment was used for testing. Two different experimenters A and B used the same sample to repeat the test 5 times respectively. The test results are as follows:

[0116] Table 1 Calcium powder water test results

[0117]

[0118]

[0119] In the test results of the two experimenters A and B, the maximum rate of the sample releasing flammable gas was greater than 20L / (kg·h), and according to the requirements of the United Nations Manual of Tests and Criteria, it should be classified as Category 2 of substances and mixtures that emit flammable gas when in contact with water; in addition, according to the Annex "Hazardous Chemical Classification Information Table" of the "Guidelines for the Implementation of the Catalog of Hazardous Chemicals (2015 Edition)" issued by the Ministry of Emergency Management, metallic calcium powder belongs to Category 2 of substances and mixtures that emit flammable gas when in contact with water. Comparison between the two proves the accuracy of the test results of this experimental device.

[0120] In the five independent tests conducted by experimenters A and B, the standard deviation and relative error were extremely close, indicating that the results of the two types of substances that release flammable gases when in contact with water detected by the present invention have high accuracy and stability, and the error of the sample detection result is more affected by the uniformity of the sample rather than the equipment detection error.

[0121] Example 2: Test on the rate at which calcium-manganese-silicon alloy powder releases flammable gas when in contact with water.

[0122] Test sample: calcium-manganese-silicon alloy powder with a median particle size of about 150 μm (containing about 17-19% calcium, 55-60% silicon, 10-16% manganese, and 10-14% iron).

[0123] According to the operation method of steps 1 to 3, the equipment was used for testing. Two different experimenters A and B used the same sample to repeat the test 5 times respectively. The test results are as follows:

[0124] Table 2 Calcium manganese silicon alloy powder water test results

[0125] Test personnel Experimenter A Experimenter B Test result 1 (L / (kg·h)) 3.856 3.701 Test result 2 (L / (kg·h)) 3.534 4.132 Test result 3 (L / (kg·h)) 3.459 3.589 Test result 4 (L / (kg·h)) 4.013 3.759 Test result 5 (L / (kg·h)) 3.758 3.592 The mean of the results 3.724 3.755 Standard Deviation 0.204 0.200 Relative error 5.483％ 5.316％

[0126] In the test results of the two experimenters A and B, the maximum rate of the sample releasing flammable gas was greater than 1L / (kg·h), and according to the requirements of the United Nations Manual of Tests and Criteria, it should be classified as flammable gas category 3; in addition, according to the "Dangerous Chemicals Classification Information Table" in the annex of the "Dangerous Chemicals Catalog (2015 Edition) Implementation Guide" issued by the Ministry of Emergency Management, calcium manganese silicon alloy belongs to the category 3 of substances and mixtures that release flammable gas when in contact with water. The comparison between the two proves the accuracy of the test results of this experimental device.

[0127] In the five independent tests conducted by experimenters A and B, the standard deviation and relative error were extremely close, indicating that the results of the three types of substances that release flammable gases when in contact with water detected by the present invention have high accuracy and stability, and the error of the sample detection results is more affected by the uniformity of the sample rather than the equipment detection error.

[0128] Example 3: Test on the rate at which flammable gas is released from magnesium-aluminum mixed powder when in contact with water.

[0129] Test sample: magnesium-aluminum powder with a median particle size of about 100 μm, with aluminum accounting for about 80% and magnesium accounting for about 20%.

[0130] According to the requirements of the United Nations Manual of Tests and Criteria 33.5.4 Test N.5: Test method for substances which release flammable gases when in contact with water, a temporary device for detecting the rate at which substances release flammable gases when in contact with water is built to test the maximum gas release rate of magnesium-aluminum powder. At the same time, the detection device of the present invention is also used to test the maximum gas release rate of magnesium-aluminum powder.

[0131] The two sets of detection devices were placed in the same fume hood in the same laboratory, and the same tester started the test at the same time. The sample was used to repeat the test 5 times. The test results of the two sets of detection devices are compared as shown in Table 3 below:

[0132] Table 3 Comparison of test results of two groups of detection devices 1

[0133] Test equipment Temporary construction of detection device Detection device of the present invention Test result 1 (L / (kg·h)) 112.6 108.534 Test result 2 (L / (kg·h)) 97.2 106.375 Test result 3 (L / (kg·h)) 105.8 115.128 Test result 4 (L / (kg·h)) 119.4 113.280 Test result 5 (L / (kg·h)) 102.5 110.817 The mean of the results 107.5 110.026 Standard Deviation 8.68 3.809

[0134] The test results of the two sets of detection devices are consistent with the hazardous chemical classification information of magnesium aluminum powder given in the "Hazardous Chemicals Catalog", which verifies the accuracy of the testing technology. At the same time, the test results of the detection device of the present invention have higher accuracy (reaching 0.001LL / (kg·h)), and the standard deviation of the 5 test results is significantly lower than that of the temporary detection device. The results show that the gas release rate detected by the detection device of the present invention has higher accuracy and better repeatability, which further verifies the stability and superiority of the detection device and technology.

[0135] Example 4: Test results of flammable gas release rate under unstable atmospheric pressure conditions.

[0136] Test sample: manganese powder with a median particle size of about 75 μm and a manganese content greater than or equal to 95%.

[0137] The same experimenter used the existing Laoying 7001 water-reacting gas measuring instrument produced by the Qingdao Laoshan Institute of Applied Technology in the laboratory to compare the test results with those of the detection device of the present invention. The test results are as follows:

[0138] Table 4 Comparison of test results of two groups of detection devices 2

[0139] Test equipment Existing detection equipment Detection device of the present invention Test result 1 (L / (kg·h)) 0.901 0.849 Test result 2 (L / (kg·h)) 0.645 0.789 Test result 3 (L / (kg·h)) 0.874 0.895 Test result 4 (L / (kg·h)) 0.739 0.842 Test result 5 (L / (kg·h)) 0.915 0.735 Test result 6 (L / (kg·h)) 0.764 0.823 Test results 7 (L / (kg·h)) 0.811 0.875 Test results 8 (L / (kg·h)) 0.765 0.735 Test results 9 (L / (kg·h)) 0.698 0.764 Test results 10 (L / (kg·h)) 0.854 0.805 The mean of the results 0.797 0.811 Standard Deviation 0.085 0.053 Relative error 10.688％ 6.521％

[0140] The test results of the two sets of detection devices are consistent with the hazardous chemical classification information of magnesium aluminum powder given in the "Hazardous Chemicals Catalog", which verifies the accuracy of the testing technology. The standard deviation and relative error of the 10 test results of the detection device of the present invention are significantly lower than those of the existing detection device. The results show that the gas release rate detected by the detection device of the present invention has better repeatability than the equipment currently used in the laboratory, which further verifies the stability and superiority of the detection device and technology.

[0141] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A device for detecting the rate at which a chemical substance releases flammable gas when in contact with water, characterized in that: The main structure of the detection device is a constant temperature box, and the entire constant temperature box is made of stainless steel and formed in one piece; The entire detection device can be divided into three parts: upper, middle and lower parts, which are: data processing and display part, detection and signal collection part, and detection temperature control part. The relevant components in the three parts are connected through signal control lines and power lines; The detection temperature control part is used to ensure that the test substance is controlled to react with water at an ambient temperature of 20°C, and maintain stable cooling and heating of the constant temperature box, including a heater, a compressor, an adjustable air outlet, an air inlet in the constant temperature box, a circulating fan, a compressor storage tank, a connecting pipe, and an exhaust pipe of the temperature control system; The detection and signal collection part consists of two reaction containers with lids on the top, one of which is a test reaction container for the actual test sample, and the other is a reference reaction container for blank control to eliminate environmental signal interference; The data processing and display part is used for setting relevant parameters in the detection process and processing and displaying relevant detection data, including equipment switches and touch screens.

2. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1 is characterized in that: The touch screen is internally connected to an embedded intelligent processor, which adopts a Panasonic GT32-E programmable intelligent operation panel, and uses its own Terminal GTWIN operation language to program, design and develop special detection software; after the test starts, the embedded intelligent processor continuously collects the real-time changes of the pressure in the test reaction container and the reference reaction container through the data port, and obtains the increase in gas volume corresponding to the pressure change through analysis and calculation by the special detection software, and displays the cumulative volume of the released gas and the release rate-time trend chart on the touch screen.

3. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1 is characterized in that: The detection-specific software consists of five modules, namely: a sample information input module, a test condition setting module, a real-time detection module, a data management module, and a data analysis module; wherein the sample information input module is used to input the information of the corresponding substance that the tester needs to detect, including the name, chemical formula, and sample number; the test condition setting module is used for the tester to set the test conditions according to the specific situation, including temperature, sample addition mass, and test time; the real-time detection module is used to collect data that needs to be monitored in real time, including gas release volume, gas release speed, and test time duration; the data management module is used for the tester to view historical test data or manage saved data; the data analysis module is used to provide charts and reports.

4. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1 is characterized in that: The detection-specific software automatically calculates the release rate and the cumulative gas release amount once every hour and saves them in a test table; the detection-specific software can obtain the current deflation rate, the current deflation volume, the maximum deflation rate and the test time, and automatically analyze the test results according to the set test parameters to determine the hazard category.

5. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1 is characterized in that: The device switch and the touch screen are both embedded in the constant temperature box.

6. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1, characterized in that: A cavity is provided in the middle of the thermostatic box, and two grooves are reserved in the bottom surface of the cavity. A reaction bottle is placed in each groove, and each reaction bottle is covered with a sealing cover. The groove of the sealing cover is embedded with a sealing rubber ring, and the sealing cover is thread-sealed and connected with the reaction bottle through the sealing rubber ring; One of the sealing covers is used as a test sealing cover, and the other sealing cover is used as a reference sealing cover; the test sealing cover and the reaction bottle constitute a test reaction container; the reference sealing cover and the reaction bottle constitute a reference reaction container; The test sealing cover is divided into an upper and lower cover structure, and the two covers are connected by threads; the outer surface of the upper cover of the test sealing cover is embedded with a micro pressure sensor, and two through holes are opened at the same time, a stainless steel air pipe is buried in one through hole, and a temperature sensor is buried in the other through hole, the stainless steel air pipe and the temperature sensor are both extended into the glass reaction bottle through the through hole of the sealing cover, the stainless steel air pipe connects the inside and outside of the reaction container and the micro pressure sensor, and the upper cover is equipped with a data line and a power line connecting the temperature sensor and the micro pressure sensor; the lower cover body of the test sealing cover is a measuring cup, which is threadedly connected to the upper cover through a connecting part, a vent is left at the bottom of the connecting part, and a circular hole for controlling the opening and closing of an electromagnetic valve is left at the bottom of the measuring cup, and the data transmission line of the electromagnetic valve is connected to the sealing cover through a waterproof quick plug connector and connected to the data transmission line; The reference sealing cover only has an upper cover structure, which is also connected with a micro pressure sensor, a stainless steel air pipe, and a temperature sensor, but does not have a measuring cup and its related connection lines. There is a vent on each of the left and right sides of the thermostatic box, which is connected to the outside and is controlled by a solenoid valve. The vent is connected to one end of the dryer through a hose, and the other end of the dryer is connected to a stainless steel air pipe through a hose. A waterproof power socket is provided on each of the side walls on both sides of the cavity; A constant temperature box door is arranged on the front of the constant temperature box body.

7. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 6, characterized in that: The volume of the cavity is set to 50L; the reaction bottle is made of high borosilicate glass with a volume of 600mL; the sealing cover is made of polytetrafluoroethylene supplemented with stainless steel; the hose is made of transparent polytetrafluoroethylene material and can be removed from the connection; the measuring cup is made of polytetrafluoroethylene material with a volume of 250mL, with a scale mark at 200mL and a liquid level sensor; the circular hole at the bottom of the measuring cup is 0.8cm, and the circular hole is initially sealed with a solenoid valve. When the power is not turned on, the circular hole is closed and watertight. After the power is turned on, the solenoid valve opens to allow the substance in the measuring cup to slowly flow into the reaction bottle; the thermostat door adopts a double-door structure with double-layer sealing, the outer door is sealed and opened with a magnetic rubber strip, the inner door is an oversized tempered glass door, and the glass door and the box body are sealed with a silicone strip.

8. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1 is characterized in that: The lower part of the constant temperature box is also an internal cavity structure, in which a heater and a compressor are arranged, and the heater and the compressor are connected by a connecting pipe; a circulating fan is connected above the heater, and an adjustable air outlet is connected above the circulating fan; a compressor liquid storage tank is also connected above the compressor, and an air inlet in the constant temperature box is connected above the compressor liquid storage tank; a temperature control system exhaust pipe is also connected between the compressor and the inner wall of the box.

9. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1, characterized in that: Each of the four corners of the outer bottom surface of the constant temperature box is provided with a universal wheel for facilitating the overall movement of the equipment; and a lighting lamp is also provided inside the constant temperature box.

10. The device for detecting the rate at which a chemical substance releases flammable gas when in contact with water according to claim 1, characterized in that: The detection process of the detection device is as follows: Step 1: Sample pretreatment; Step 1.1: For solid substances, check whether there are any particles with a diameter of less than 500 microns in the package. If such powder accounts for more than 1% of the total mass of the substance, or the substance is friable, grind all the samples into powder before testing; Step 1.2: Perform a preliminary screening test on the substance to be tested according to the following steps. If spontaneous combustion occurs at any of the following stages, no further testing is required; Step 1.2.

1. Place a small amount of the test substance in a sink containing 20°C distilled water; Step 1.2.2: Place a small amount of the test substance at the center of a piece of filter paper floating flat on the surface of 20°C distilled water in a suitable container; Step 1.2.3, make a pile of the test substance with a height of about 20 mm and a diameter of about 30 mm, make a groove on the top of the pile, and add a few drops of water into the groove; Step 2: Perform the test according to the following process; Step 2.1, during the test, the test reaction container is added with the sample for testing, and the reference reaction container is not added with the sample but only with 200 ml of distilled water as a control reference; Step 2.2, turn on the power of the equipment, open the thermostat, unplug the line quick plug connectors and dryers on each reaction container, and take out the two reaction containers; Step 2.3, weigh the sample to be tested using a balance. The sample mass cannot exceed 25 grams; Step 2.4, unscrew the test sealing cover, add up to 25g of the substance to be tested into the reaction bottle; unscrew the polytetrafluoroethylene measuring cup under the sealing cover, add 200ml of distilled water into it, and then screw it back into the lower layer of the sealing cover; put the test sealing cover on the reaction bottle containing the sample and tighten it to make it sealed; Step 2.5, unscrew the reference sealing cap, add 200 mL of distilled water to the reaction bottle, and then install the reference sealing cap on the reaction bottle and tighten it to make it sealed; Step 2.6, place the two sealed reaction bottles into the grooves on the bottom of the cavity of the constant temperature box and fix them, connect the dryer and the quick-connect connector, and then close the door of the constant temperature box; Step 2.7, open the detection software, select the corresponding connection port, and set the water bath temperature to 20℃; Step 2.8, enter the sample number, sample material and customer object information in the corresponding interface of the detection software, set the file storage path, click the start button and automatically balance, after the temperature in the reaction bottle stabilizes at 20°C, the solenoid valve opens, the water in the test reaction container begins to flow down slowly, and the device automatically starts testing; Step 2.9: After the test, save the test data, turn off the equipment, disassemble and clean the reaction bottle and dry it; Step 3: Determine the test results; Step 3.

1. Substances meeting the following conditions are classified as hazard types: in contact with water, they emit flammable gases: spontaneous combustion occurs at any step of the test procedure, or the rate of release of flammable gases is greater than 1 litre per kilogram of substance per hour; Step 3.2: Materials that meet the following conditions are classified in Packing Group I / Category 1: They react violently with water at ambient temperature and the gases produced usually show a tendency to spontaneous combustion, or they react readily with water at ambient temperature and release flammable gases at a rate greater than or equal to 10 litres per kilogram of material in any one minute; Step 3.3: Materials that meet the following conditions are classified in Packing Group II / Category 2: They react readily with water at ambient temperature, release flammable gases at a maximum rate greater than or equal to 20 litres per kilogram of material per hour, and do not meet the criteria for Packing Group I / Category 1; Step 3.4: Materials that meet the following conditions are classified in Packing Group III / Category 3: They react slowly with water at ambient temperature, the maximum rate of release of flammable gas is greater than 1 litre per kilogram of material per hour, and do not meet the criteria for Packing Groups I and II / Categories 1 and 2.

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