GB 18098-2000 Determination of toxic gas content after explosion of industrial explosives
Some standard content:
GB18098-2000
The toxic gas content after the explosion of industrial explosives is an important indicator to ensure the safety of mining operations, and strict tests and inspections are required. This standard is formulated on the basis of WJ1977-1990 "Method for Determination of Toxic Gas Content after Explosion of Industrial Explosives" and MT60--1995 "Method for Determination of Toxic Gas Content after Explosion of Permissible Explosives in Coal Mines and Judgment Rules", and in accordance with the requirements of the GB/T1 series of standards. This standard is proposed by the National Defense Science, Technology and Industry Commission. This standard is under the jurisdiction of the China Ordnance Industry Standardization Research Institute. The drafting units of this standard are: National Civilian Explosives Quality Supervision and Inspection Center, National Civilian Explosives Product Changsha Quality Supervision and Inspection Station, Coal Industry Zhunbei Explosives Product Quality Supervision and Inspection Center, National Coal Mine Explosion-proof Safety Product Quality Supervision and Inspection Center, China Ordnance Industry Standardization Research Institute.
The main drafters of this standard are: Wu Weiqin, Li Jianxiang, Ni Ouqi, Xia Bin, Duan, Yang Jinxia, Zheng Xiuying. 820
1 Scope
National Standard of the People's Republic of China
Determination of the toxic gases formedby detonation of industrial explosivesGB 18098—2000
This standard specifies the preparation method of gas samples after explosion of industrial explosives, the reagents and materials, instruments and equipment used for the determination of toxic gas content, the test procedures and the expression of test results. This standard is applicable to the determination of toxic gas (carbon monoxide and nitrogen oxides) content after explosion of industrial explosives. 2 Referenced Standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and parties using this standard should explore the possibility of using the latest versions of the following standards. Chemical reagent sulfuric acid
GB/T 625--1989
GB/T 629—1997
GB/T 631—1989
GB/T 633—1994
GB/T 658-1988
GB/T678
—1990
GB/T 1266—1986
GB/T 1282—1996
GB/T 1294—1993
GB/T 2306—1997
GB/T 6684—1986
GB/T 8031—1987
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Chemical reagents
Sodium hydroxide
Sodium nitrite
Ammonium chloride
Ethanol (anhydrous ethanol)
Sodium chloride
Tartaric acid
Potassium hydroxide
30% hydrogen peroxide
Chemical reagents
Industrial lightning
GB/T15349--1994
HG/T3-95—1976
Chemical reagent
Methyl red
HG/T3-1287--1980
Chemical reagent
3 Summary of method
Potassium bromophenol green
Curous chloride
Under certain conditions, a certain amount of explosives is exploded in an explosive shell of a certain volume to obtain a gas sample after the explosion of the explosives. The contents of carbon monoxide and nitrogen oxides in the gas sample are determined respectively and then converted into the total content of toxic gases. 4 Preparation of gas samples
4.1 Method - (Arbitration method)
4.1.1 Reagents and materials
Approved by the State Administration of Quality and Technical Supervision on May 9, 2000 and implemented on July 1, 2000
GB 180982000
a) Detonator: GB/T8031, No. 8 metal shell instantaneous detonator; b) Quartz sand: silicon dioxide content not less than 90%, particle size 0.40mm~~0.63mm. 4.1.2 Instruments and devices
4.1.2.1 Instruments
a) Moving tank mercury pressure gauge: measurement accuracy is 0.04kPa; b) Thermometer: graduation value is 0.2℃;
c) Balance: sensitivity is 0.5g;
d) Sampler; sampling bottle, ball bladder, etc.
4.1.2.2 Preparation device
The schematic diagram of the gas sample preparation device (1) is shown in Figure 1. a) Explosive shell: a steel cylinder with an outer diameter of 600mm, an inner diameter of 350mm and an inner depth of 550mm; b) Steel cannon: a cylinder with an outer diameter of 240mm and a height of 300mm, with a central hole diameter of 45mm and a depth of 200mm; c) Vacuum pump;
d) Pressure gauge: measuring range of 0MPa~0.1MPa, 1.5 level; e) Vacuum gauge 1.5 level;
f) U-type mercury differential pressure gauge: the graduation value is 0.133kPa. 4.1.3 Preparation steps
4.1.3.1 Check the preparation device. The inner wall of the explosive shell should be clean, there should be no dust and rust on the terminal, and all valves should be unobstructed. 4.1.3.2 Weigh 110.0g ± 0.5g of the original explosive roll (if the diameter is greater than 35mm, it should be modified to a diameter of 35mm), insert the detonator into the center of the explosive roll, the insertion depth is 2/3 of the total length of the detonator, and then install it into the inner hole of the steel cannon. Then weigh 300.0g ± 0.5g of quartz sand, naturally fill it around and on the top of the explosive roll, and connect the detonator legs to the two terminals respectively. 4.1.3.3 Close the cover of the explosive cartridge, start the vacuum pump to exhaust, and stop exhausting when the residual pressure in the explosive cartridge is no more than 4.0kPa. 4.1.3.4 Detonate the explosive, wait for the gas in the explosive cartridge to cool to room temperature, and read the atmospheric pressure, room temperature and U-type mercury differential pressure gauge pressure difference. The atmospheric pressure should be corrected for temperature and latitude. 4.1.3.5 Collect gas samples with a sampler. 1-explosive cartridge 2-steel cannon; 3-powder roll; 4-detonator; 5---explosive cartridge cover; 6--main valve; 7-pressure gauge; 8-three-way valve; 9-vacuum gauge; 10-vacuum pump; 11--U-type mercury differential pressure gauge; 12-sampling valve Figure 1 Schematic diagram of gas sample preparation device (1) 822
4.2 Method 2
4.2.1 Reagents and materials
GB 18098--2000
a) Detonator: GB/T8031, No. 8 metal shell instantaneous detonator; b) Quartz sand: silicon dioxide content not less than 90%, particle size 0.40mm~~0.63mm, clean; c) Glass cartridge: use 95 glass to make a flat-bottomed round cartridge corresponding to the outer diameter of the test powder roll. 4.2.2 Instruments and devices
4.2.2.1 Instruments
a) Moving tank mercury pressure gauge: measuring accuracy is 0.04 kPa; b) Absorbance meter: graduation value is 0.2℃;
c) Balance: sensitivity is 0.5g;
d) Sampler: sampling bottle, bladder, etc.
4.2.2.2 Devices
The schematic diagram of the gas sample preparation device (2) is shown in Figure 2. a) Explosive shell: a steel cylinder with a volume of not less than 15L; b) Vacuum pump;
c) Pressure gauge: measuring range is 0MPa～0.1MPa, 1.5 level; d) Vacuum gauge: 1.5 level;
e) U-type mercury differential pressure gauge: graduation value is 0.133 kPa. 8
1—explosive cartridge; 2—explosive cartridge cover; 3—detonating plug; 4—main valve; 5—pressure gauge; 6—three-way valve; 7—vacuum gauge; 8—vacuum pump; 9—U-type mercury differential pressure gauge; 10—sampling valve Figure 2 Schematic diagram of gas sample preparation device (2) 4.2.3 Preparation steps
4.2.3.1 Check the preparation device. The inner wall of the explosive cartridge should be clean, the sealing gasket should be intact, and all valves should be unobstructed. 4.2.3.2 Weigh 110.0g ± 0.5g of the original explosive roll (if the diameter is greater than 35mm, it should be modified to a diameter of 35mm), and put it into a glass cylinder of corresponding diameter 823
GB18098-2000
and known mass to make a powder bag. Insert the detonator into the center of the powder bag to a depth of 2/3 of the total length of the detonator. Then weigh a certain amount of quartz sand (the total mass of quartz sand and glass cylinder is about 110g) and cover it on the top of the charge. Stack it naturally and do not allow pressurization. 4.2.3.3 Suspend the powder bag in the explosive shell, and connect the detonator leg wire to the detonating electrode. 4.2.3.4 Close the cover of the explosive shell, start the vacuum pump to evacuate, and stop evacuating when the residual pressure in the explosive shell is no more than 4.0kPa. 4.2.3.5 Detonate the explosives, and after the gas in the explosive shell cools to room temperature, read the atmospheric pressure, room temperature, and the pressure difference of the U-type mercury differential pressure gauge. The atmospheric pressure should be corrected for temperature and latitude. 4.2.3.6 Use a bladder to collect gas samples for the determination of carbon monoxide content. Before collection, the bladder should be rinsed three times with the gas sample; use a sampling bottle to collect gas samples for the determination of nitrogen oxide content. 5 Determination of toxic gas content
5.1 Determination of carbon monoxide content
5.1.1 Chemical absorption method (arbitration method)
5.1.1.1 Principle
In the gas sample, carbon dioxide is absorbed by potassium hydroxide solution, oxygen is absorbed by pyrogallic acid solution, and carbon monoxide is absorbed by cuprous chloride ammonia solution. The volume fraction of carbon monoxide can be calculated by measuring the volume change before and after. 5.1.1.2 Reagents and materials
a) Copper filings: copper filings;
b) Liquid paraffin;
c) Pyrogallic acid;
d) Methyl orange;
e) Potassium hydroxide solution: Use potassium hydroxide (GB/T2306) to prepare a solution with a mass fraction of 25% to 33%; f) Cuprous chloride ammonia solution: Weigh about 250g of ammonium chloride (GB/T658) and dissolve it in 750mL of water, add about 200g of cuprous chloride (HG/T3-1287) and stir thoroughly, then add about 1/8 of the volume of the solution of ammonia water (GB /T631), add 2g~3g copper chips and liquid paraffin with a thickness of 2cm~3cm;
g) Potassium pyrogallate solution: weigh about 28g pyrogallate, dissolve in 50mL hot water, cool, add 130mL potassium hydroxide solution,
h) Sulfuric acid solution: use sulfuric acid (GB/T625) to prepare a solution with a mass fraction of 10%;i) Methyl orange solution: use methyl orange to prepare a solution with a mass fraction of 0.2%;j) Sealing solution: use sulfuric acid solution and sodium chloride (GB/T1266) to prepare a saturated solution, and then add a few drops of methyl orange solution. 5.1.1.3 Instruments and equipment
The schematic diagram of the gas analyzer is shown in Figure 3.
5.1.1.4 Test steps
GB 18098--2000
1, 2, 3, 4—Absorption bottle; 5—Gas inlet pipe; 6—Filter tube; 7—Three-way valve; 8—Comb tube; 9—Double-arm gas tube; 10—Level bottle Figure 3 Schematic diagram of gas analyzer
5.1.1.4.1 Fill absorption bottle 1 with potassium hydroxide solution, absorption bottle 2 with potassium pyrogallate solution, absorption bottle 3 with cuprous chloride ammonium solution, absorption bottle 4 with sulfuric acid solution, and place liquid paraffin on the liquid surface of each absorption bottle. Fill the sealing liquid into the level bottle, and fill the water jacket of the double-arm gas tube with distilled water. 5.1.1.4.2 Check whether the measurement system is leaking according to the operating instructions of the gas analyzer. 5.1.1.4.3 Pass 100.0mL±0.1mL of gas sample into the double-arm gas measuring tube. 5.1.1.4.4 Press the gas sample in the double-arm gas measuring tube into absorption bottle 1 and absorption bottle 2 in turn, and absorb repeatedly until carbon dioxide and oxygen are completely absorbed. Then press it into absorption bottle 3 to absorb carbon monoxide, and press it into absorption bottle 4 to remove ammonia. Measure the volume of the remaining gas after absorption.
5.1.1.5 Expression of test results
The carbon oxide content in the gas sample is calculated according to formula (1). 9
Where: 9
Volume fraction of carbon oxide in the gas sample, %; V1—Volume of gas before passing through absorption bottle 3, mL; V2—Volume of gas after passing through absorption bottle 4, mL; V2—Volume of gas sample, mL.
Perform two parallel determinations, and the allowable difference should not be greater than 0.5%. Take the arithmetic mean as the result, and the result is accurate to 0.1%. 5.1.2 Infrared gas analyzer method
5.1.2.1 Principle
GB 18098-2000
According to the characteristic absorption of carbon monoxide to infrared light of a certain wavelength, and the carbon monoxide content and energy loss conform to Beer's law, the result is directly measured by calibration with carbon monoxide standard gas. 5.1.2.2 Reagents and materials
Carbon monoxide standard gas: The carbon monoxide content in the standard gas should be close to the carbon monoxide content in the measured component. 5.1.2.3 Instruments and equipment
Infrared gas analyzer: The accuracy should not be less than 0.1%. 5.1.2.4 Test steps
5.1.2.4.1 Start the infrared gas analyzer, wait for it to stabilize, calibrate the zero point, and pass carbon monoxide standard gas to calibrate the full scale. 5.1.2.4.2 Pass a certain amount of gas sample into the infrared gas analyzer and measure the volume fraction of carbon monoxide. 5.1.2.5 Expression of test results
Parallel determination is performed twice, and the allowable difference should not be greater than 0.5%. Take the arithmetic mean as the result, and the result is accurate to 0.1%. 5.1.3 Gas chromatography
5.1.3.1 Principle
Different substances have different distribution coefficients in different two phases (gas, solid or liquid). When the two phases move relative to each other, these substances are repeatedly distributed in the two phases, so that those components with only slight differences in distribution coefficients have a great separation effect. 5.1.3.2 Reagents and materials
a) Stationary phase: 13X molecular sieve, pore size 0.15mm~0.20mm; b) Carrier gas: fluorine gas, purity 99.99%; c) Carbon monoxide standard gas: The carbon monoxide content in the standard gas should be close to the carbon monoxide content in the measured component. 5.1.3.3 Instruments and equipment
a) Gas chromatograph;
b) Chromatographic column: inner diameter 3mm, length 2m, filled with 13X molecular sieve; c) Detector: thermal conductivity detector;
d) Chromatographic data processor: dedicated microcomputer. 5.1.3.4 Chromatographic conditions
a) Column temperature: 50℃;
b) Detector temperature: 100℃;
c) Carrier gas flow rate: 20 mL/min～40 mL/min; d) Column head pressure: 0.1MPa.
5.1.3.5 Test steps
5.1.3.5.1 Start the gas chromatograph according to the steps in the instrument manual, adjust the gas chromatograph to a usable state according to the chromatographic conditions, and set the working parameters of the chromatographic data processor after the baseline is stable. 5.1.3.5.2 Pass carbon monoxide standard gas into the gas chromatograph three times and calculate the correction factor of carbon monoxide (calculated automatically by the chromatographic data processor).
5.1.3.5.3 Pass a certain amount of gas sample into the gas chromatograph and measure the carbon monoxide content and measurement error. 5.1.3.6 Expression of test results
Perform three parallel determinations, and the allowable difference should not be greater than 0.5%. Take the arithmetic mean of the three parallel determinations as the result, and the result is accurate to 0.1%.
5.2 Determination of nitrogen oxide content
5.2.1 Volumetric analysis method (arbitration method)
5.2.1.1 Principle
GB 18098 ---2000
The nitrogen oxides contained in the explosive gas are mainly nitrogen monoxide and nitrogen dioxide. The nitrogen monoxide is oxidized to nitrogen dioxide by hydrogen peroxide, and the nitrogen dioxide is absorbed by water to form acid, which is titrated with a standard alkaline solution. The content of nitrogen oxides in the product can be calculated based on the consumption of the alkaline solution.
5.2.1.2 Reagents and materials
a) Anhydrous ethanol: GB/T 678;
b) Sodium dodecylbenzene sulfonate solution: the mass fraction of sodium dodecylbenzene sulfonate is 1%; c) Hydrogen peroxide solution: the mass fraction is 3%, prepared with 30% hydrogen peroxide (GB/T6684); d) Bromocresol green ethanol solution: use bromocresol green (GB/T15349) to prepare a bromocresol green ethanol solution with a mass fraction of 0.1%; e) Methyl red ethanol solution: use methyl red (HG/T3-95) to prepare a methyl red ethanol solution with a mass fraction of 0.2%; f) Sodium hydroxide standard solution: use sodium hydroxide (GB/T629) to prepare a sodium hydroxide standard solution with a concentration of 0.1 mol/L; g) Mixed indicator: Bromocresol green ethanol solution and methyl red ethanol solution are mixed in a volume ratio of 3:1. 5.2.1.3 Instruments and equipment
Sampling bottle: 1000mL~3000mL
5.2.1.4 Test steps
5.2.1.4.1 Fill the sampling bottle with 100mL hydrogen peroxide solution and 2mL sodium dodecylbenzene sulfonate solution, evacuate the sampling bottle until the residual pressure is no more than 4.0kPa, fill it with 1000mL~3000mL gas sample, shake it vigorously for 10min, and let it stand for 5min~10min.
5.2.1.4.2 Transfer the absorption liquid in the sampling bottle to a 500mL conical flask, rinse the sampling bottle with water, heat it to boil, cool it to room temperature, add 2~3 drops of mixed indicator, and use 0.1mol/L sodium hydroxide standard solution is titrated until the green color is the end point. 5.2.1.5 Expression of test results
The content of nitrogen oxides in the gas sample is calculated according to formula (2). 22. 4 Xg×V: × 100
Wherein: 92—nitrogen oxide volume fraction, %; c,—concentration of sodium hydroxide standard solution, mol/L; V3-volume of sodium hydroxide standard solution consumed in titration, mL; V\—volume of gas sample under standard conditions, mL. Parallel determination is performed twice, and the allowable difference should not be greater than 0.2%. The arithmetic mean is taken as the result, and the result is accurate to 0.01%. 5.2.2 Spectrophotometry
5.2.2.1 Principle
When explosives explode, the nitrogen oxides generated are nitric oxide and nitrogen dioxide. The nitric oxide is oxidized into nitrogen dioxide by oxygen in the air, and the nitrogen dioxide is absorbed by the sodium hydroxide solution to generate nitrate and nitrite. When a color developer is added, it turns pink. The degree of color development is proportional to the nitrogen dioxide content, and the nitrogen dioxide content can be measured by spectrophotometry. 5.2.2.2 Reagents and materials
a) Sodium hydroxide solution: Prepare a solution with a concentration of 0.1 mol/L using sodium hydroxide (GB/T629); b) Absorption solution: Prepare a solution by mixing sodium hydroxide solution with anhydrous ethanol (GB/T678) in a volume ratio of 1:2; c) Sodium nitrite stock solution: Weigh 0.1500 g ± 0.0010 g of sodium nitrite (GB/T633) and put it into a 1000 mL volumetric flask, dilute it to the mark with distilled water, shake it to obtain solution A; pipette 100 mL of solution A and transfer it to another 1000 mL volumetric flask, dilute it to the mark with distilled water, shake it to obtain solution B; d) Sodium nitrite standard solution (1 ml. The solution contains 0.0015 mg NaNOz, equivalent to 0.002 mg NOz): Use a pipette to transfer 10 ml of sodium nitrite stock solution (solution B) into a 100 ml volumetric flask, dilute to the scale with absorption liquid, and shake well; e) Color developer: Mix naphthyl diaminoethylene hydrochloride (chemically pure), p-aminobenzenesulfonamide and tartaric acid (GB/T1294) in a mass ratio of 1:4:95, grind and mix evenly in a mortar, put into a brown bottle, and place in a desiccator for use; 827
GB18098—2000
f) Color developer solution: Weigh about 30 g of color developer and dissolve it in 100 ml of 4% phosphoric acid (GB/T1282) solution by mass fraction, and prepare it when used.
5.2.2.3 Instruments and equipment
a) Analytical balance: sensitivity 0.1 mg;
b) Pipette: 10 mL, 25 mL;
c) Graduated pipette: 1 mL (minimum graduation value is 0.01 mL), 5 mL (minimum graduation value is 0.05 mL), 10 mL (minimum graduation value is 0.1 mL);
d) Spectrophotometer;
e) Sampling bottle.
5.2.2.4 Test steps
5.2.2.4.1 Drawing of working curve
Use a graduated pipette to draw 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 6.0, 7.0 mL of sodium nitrite standard solution into a colorimetric tube (the corresponding nitrogen dioxide mass is 0, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.008, 0.010, 0.012, 0.014 mg), and add absorption liquid to the 15 mL scale. Use a pipette to draw 5 mL of color developer solution and add it to the colorimetric tube. Then, place the colorimetric tube in a constant temperature water bath at 25°C ± 1°C and keep it warm for about 30 minutes to allow it to fully develop color. On a spectrophotometer, use 1 cm colorimetric blood and zero standard solution as reference to determine the absorbance of each standard solution at a wavelength of 545 nm. Draw a working curve with the mass of nitrogen dioxide as the horizontal axis and the absorbance as the vertical axis. 5.2.2.4.2 Determination of nitrogen dioxide
Take 40 mL of gas sample respectively and inject it into two vacuum sampling bottles containing 15 mL of nitrogen dioxide absorption liquid. After 24 hours of oxidation and absorption, the gas sample is used for determination.
Accurately pipette 5 mL of color developer solution into the sampling bottle and determine the absorbance according to the method described in 5.2.2.4.1 with the reagent blank solution as reference. According to the absorbance, find the mass of nitrogen dioxide corresponding to the sample on the working curve and then convert it into the volume fraction of nitrogen dioxide. 5.2.2.5 Expression of test results
The content of nitrogen oxides in the gas sample is calculated according to formula (3). = a×64×10 × 100
Wherein: 9—
—Volume fraction of nitrogen oxides in the gas sample, %; a—-—Mass of NOz obtained from the working curve, mg; 6.4×10-5——Conversion coefficient, L/mg; V. \—-Volume of the gas sample under standard conditions, L. Parallel determination is performed twice, and the allowable difference should not be greater than 0.3%. The arithmetic mean is taken as the result, and the result is accurate to 0.01%. 5.3 Calculation of the total amount of toxic gas
5.3.1 Under standard conditions, the total volume of gas after explosion per kilogram of explosive is calculated according to formula (4). Ve=
Wherein: V-
V, × (P. + P, - P, - P,) × 273 × 1 000101.3 X (273 + t)m
-The volume of gas produced after the explosion of each kilogram of explosive under standard conditions, L/kg; (3)
Gas sample preparation method 1 is the actual volume of the explosive shell after deducting the volume occupied by the steel cannon, L; Gas sample preparation method 2 is the actual volume of the explosive shell, L; P.--The pressure difference value of the U-type mercury differential pressure gauge, kPa; P,-The atmospheric pressure during measurement, kPa;
P,The residual pressure in the shell when evacuated, kPa; P
The saturated water vapor pressure of air at temperature t, kPa; 828
GB18098-2000
Conversion constant for absolute temperature and Celsius temperature; Conversion factor for kilogram and gram;
The product of the conversion factor of 0.1333 between millimeters of mercury and kilopascals and the atmospheric pressure of 760 mmHg under standard conditions. Room temperature during measurement, C;
Mass of the test roll, g.
5.3.2 The volume of carbon monoxide and nitrogen oxides generated after the explosion of each kilogram of explosive is calculated according to formula (5) and (6) respectively. =V×
V\= V. × P
Where: V!
The volume of carbon monoxide generated after the explosion of each kilogram of explosive, L/kg; V. The volume of gas generated after the explosion of each kilogram of explosive under standard conditions, L/kg; 9
The volume fraction of carbon monoxide in the gas sample, %; -The volume of nitrogen oxides generated after the explosion of each kilogram of explosive, L/kg; The volume fraction of nitrogen oxides in the gas sample, %. ...( 5)
·(6)
5.3.3 The total amount of toxic gas generated after the explosion of each dry gram of explosive (converted into carbon monoxide under standard conditions) is calculated according to formula (7). V=V+ 6.5V\
Wherein, V-
The total amount of toxic gas generated after the explosion of each kilogram of explosives, L/kg; -The volume of carbon monoxide generated after the explosion of each kilogram of explosives, L/kg; 6.5-The toxicity coefficient when converting nitrogen oxides into carbon monoxide; \-The volume of nitrogen oxides generated after the explosion of each dry gram of explosives, L/kg. Parallel determination is performed twice, and the allowable difference should not exceed 10L/kg. The larger value is taken as the final result and rounded to the nearest digit. (7)1mol/L solution; b) Absorption solution: Mix sodium hydroxide solution and anhydrous ethanol (GB/T678) in a volume ratio of 1:2; c) Sodium nitrite stock solution: Weigh 0.1500g ± 0.0010g sodium nitrite (GB/T633), put it into a volumetric flask with a volume of 1000mL, dilute it to the mark with distilled water, shake it, and use it as solution A; use a pipette to draw 100mL solution A, transfer it to another volumetric flask with a volume of 1000mL, dilute it to the mark with distilled water, shake it, and use it as solution B; d) Sodium nitrite standard solution (1ml. This solution contains 0.0015mgNaNOz, equivalent to 0.00 2mgNOz): Use a pipette to transfer 10ml of sodium nitrite stock solution (solution B) into a 100ml volumetric flask, dilute to the mark with absorption solution, and shake well; e) Color developer: Mix naphthyl diaminoethylene hydrochloride (chemically pure), p-aminobenzenesulfonamide and tartaric acid (GB/T1294) in a mass ratio of 1:4:95, grind and mix evenly in a mortar, put into a brown bottle, and place in a desiccator for use; 827
GB18098—2000
f) Color developer solution: Weigh about 30g of color developer and dissolve it in 100ml of 4% phosphoric acid (GB/T1282) solution by mass fraction, and prepare it before use.
5.2.2.3 Instruments and equipment
a) Analytical balance: sensitivity 0.1 mg;
b) Pipette: 10 mL, 25 mL;
c) Graduated pipette: 1 mL (minimum graduation value is 0.01 mL), 5 mL (minimum graduation value is 0.05 mL), 10 mL (minimum graduation value is 0.1 mL);
d) Spectrophotometer;
e) Sampling bottle.
5.2.2.4 Test steps
5.2.2.4.1 Drawing of working curve
Use a graduated pipette to draw 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 6.0, 7.0 mL of sodium nitrite standard solution into a colorimetric tube (the corresponding nitrogen dioxide mass is 0, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.008, 0.010, 0.012, 0.014 mg), and add absorption liquid to the 15 mL scale. Use a pipette to draw 5 mL of color developer solution and add it to the colorimetric tube. Then, place the colorimetric tube in a constant temperature water bath at 25°C ± 1°C and keep it warm for about 30 minutes to allow it to fully develop color. On a spectrophotometer, use 1 cm colorimetric blood and zero standard solution as reference to determine the absorbance of each standard solution at a wavelength of 545 nm. Draw a working curve with the mass of nitrogen dioxide as the horizontal axis and the absorbance as the vertical axis. 5.2.2.4.2 Determination of nitrogen dioxide
Take 40 mL of gas sample respectively and inject it into two vacuum sampling bottles containing 15 mL of nitrogen dioxide absorption liquid. After 24 hours of oxidation and absorption, the gas sample is used for determination.
Accurately pipette 5 mL of color developer solution into the sampling bottle and determine the absorbance according to the method described in 5.2.2.4.1 with the reagent blank solution as reference. According to the absorbance, find the mass of nitrogen dioxide corresponding to the sample on the working curve and then convert it into the volume fraction of nitrogen dioxide. 5.2.2.5 Expression of test results
The content of nitrogen oxides in the gas sample is calculated according to formula (3). = a×64×10 × 100
Wherein: 9—
—Volume fraction of nitrogen oxides in the gas sample, %; a—-—Mass of NOz obtained from the working curve, mg; 6.4×10-5——Conversion coefficient, L/mg; V. \—-Volume of the gas sample under standard conditions, L. Parallel determination is performed twice, and the allowable difference should not be greater than 0.3%. The arithmetic mean is taken as the result, and the result is accurate to 0.01%. 5.3 Calculation of the total amount of toxic gas
5.3.1 Under standard conditions, the total volume of gas after explosion per kilogram of explosive is calculated according to formula (4). Ve=
Wherein: V-
V, × (P. + P, - P, - P,) × 273 × 1 000101.3 X (273 + t)m
-The volume of gas produced after the explosion of each kilogram of explosive under standard conditions, L/kg; (3)
Gas sample preparation method 1 is the actual volume of the explosive shell after deducting the volume occupied by the steel cannon, L; Gas sample preparation method 2 is the actual volume of the explosive shell, L; P.--The pressure difference value of the U-type mercury differential pressure gauge, kPa; P,-The atmospheric pressure during measurement, kPa;
P,The residual pressure in the shell when evacuated, kPa; P
The saturated water vapor pressure of air at temperature t, kPa; 828
GB18098-2000
Conversion constant for absolute temperature and Celsius temperature; Conversion factor for kilogram and gram;
The product of the conversion factor of 0.1333 between millimeters of mercury and kilopascals and the atmospheric pressure of 760 mmHg under standard conditions. Room temperature during measurement, C;
Mass of the test roll, g.
5.3.2 The volume of carbon monoxide and nitrogen oxides generated after the explosion of each kilogram of explosive is calculated according to formula (5) and (6) respectively. =V×
V\= V. × P
Where: V!
The volume of carbon monoxide generated after the explosion of each kilogram of explosive, L/kg; V. The volume of gas generated after the explosion of each kilogram of explosive under standard conditions, L/kg; 9
The volume fraction of carbon monoxide in the gas sample, %; -The volume of nitrogen oxides generated after the explosion of each kilogram of explosive, L/kg; The volume fraction of nitrogen oxides in the gas sample, %. ...( 5)
·(6)
5.3.3 The total amount of toxic gas generated after the explosion of each dry gram of explosive (converted into carbon monoxide under standard conditions) is calculated according to formula (7). V=V+ 6.5V\
Wherein, V-
The total amount of toxic gas generated after the explosion of each kilogram of explosives, L/kg; -The volume of carbon monoxide generated after the explosion of each kilogram of explosives, L/kg; 6.5-The toxicity coefficient when converting nitrogen oxides into carbon monoxide; \-The volume of nitrogen oxides generated after the explosion of each dry gram of explosives, L/kg. Parallel determination is performed twice, and the allowable difference should not exceed 10L/kg. The larger value is taken as the final result and rounded to the nearest digit. (7)1mol/L solution; b) Absorption solution: Mix sodium hydroxide solution and anhydrous ethanol (GB/T678) in a volume ratio of 1:2; c) Sodium nitrite stock solution: Weigh 0.1500g ± 0.0010g sodium nitrite (GB/T633), put it into a volumetric flask with a volume of 1000mL, dilute it to the mark with distilled water, shake it, and use it as solution A; use a pipette to draw 100mL solution A, transfer it to another volumetric flask with a volume of 1000mL, dilute it to the mark with distilled water, shake it, and use it as solution B; d) Sodium nitrite standard solution (1ml. This solution contains 0.0015mgNaNOz, equivalent to 0.00 2mgNOz): Use a pipette to transfer 10ml of sodium nitrite stock solution (solution B) into a 100ml volumetric flask, dilute to the mark with absorption solution, and shake well; e) Color developer: Mix naphthyl diaminoethylene hydrochloride (chemically pure), p-aminobenzenesulfonamide and tartaric acid (GB/T1294) in a mass ratio of 1:4:95, grind and mix evenly in a mortar, put into a brown bottle, and place in a desiccator for use; 827
GB18098—2000
f) Color developer solution: Weigh about 30g of color developer and dissolve it in 100ml of 4% phosphoric acid (GB/T1282) solution by mass fraction, and prepare it before use.
5.2.2.3 Instruments and equipment
a) Analytical balance: sensitivity 0.1 mg;
b) Pipette: 10 mL, 25 mL;
c) Graduated pipette: 1 mL (minimum graduation value is 0.01 mL), 5 mL (minimum graduation value is 0.05 mL), 10 mL (minimum graduation value is 0.1 mL);
d) Spectrophotometer;
e) Sampling bottle. bzxZ.net
5.2.2.4 Test steps
5.2.2.4.1 Drawing of working curve
Use a graduated pipette to draw 0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 6.0, 7.0 mL of sodium nitrite standard solution into a colorimetric tube (the corresponding nitrogen dioxide mass is 0, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.008, 0.010, 0.012, 0.014 mg), and add absorption liquid to the 15 mL scale. Use a pipette to draw 5 mL of color developer solution and add it to the colorimetric tube. Then, place the colorimetric tube in a constant temperature water bath at 25°C ± 1°C and keep it warm for about 30 minutes to allow it to fully develop color. On a spectrophotometer, use 1 cm colorimetric blood and zero standard solution as reference to determine the absorbance of each standard solution at a wavelength of 545 nm. Draw a working curve with the mass of nitrogen dioxide as the horizontal axis and the absorbance as the vertical axis. 5.2.2.4.2 Determination of nitrogen dioxide
Take 40 mL of gas sample respectively and inject it into two vacuum sampling bottles containing 15 mL of nitrogen dioxide absorption liquid. After 24 hours of oxidation and absorption, the gas sample is used for determination.
Accurately pipette 5 mL of color developer solution into the sampling bottle and determine the absorbance according to the method described in 5.2.2.4.1 with the reagent blank solution as reference. According to the absorbance, find the mass of nitrogen dioxide corresponding to the sample on the working curve and then convert it into the volume fraction of nitrogen dioxide. 5.2.2.5 Expression of test results
The content of nitrogen oxides in the gas sample is calculated according to formula (3). = a×64×10 × 100
Wherein: 9—
—Volume fraction of nitrogen oxides in the gas sample, %; a—-—Mass of NOz obtained from the working curve, mg; 6.4×10-5——Conversion coefficient, L/mg; V. \—-Volume of the gas sample under standard conditions, L. Parallel determination is performed twice, and the allowable difference should not be greater than 0.3%. The arithmetic mean is taken as the result, and the result is accurate to 0.01%. 5.3 Calculation of the total amount of toxic gas
5.3.1 Under standard conditions, the total volume of gas after explosion per kilogram of explosive is calculated according to formula (4). Ve=
Wherein: V-
V, × (P. + P, - P, - P,) × 273 × 1 000101.3 X (273 + t)m
-The volume of gas produced after the explosion of each kilogram of explosive under standard conditions, L/kg; (3)
Gas sample preparation method 1 is the actual volume of the explosive shell after deducting the volume occupied by the steel cannon, L; Gas sample preparation method 2 is the actual volume of the explosive shell, L; P.--The pressure difference value of the U-type mercury differential pressure gauge, kPa; P,-The atmospheric pressure during measurement, kPa;
P,The residual pressure in the shell when evacuated, kPa; P
The saturated water vapor pressure of air at temperature t, kPa; 828
GB18098-2000
Conversion constant for absolute temperature and Celsius temperature; Conversion factor for kilogram and gram;
The product of the conversion factor of 0.1333 between millimeters of mercury and kilopascals and the atmospheric pressure of 760 mmHg under standard conditions. Room temperature during measurement, C;
Mass of the test roll, g.
5.3.2 The volume of carbon monoxide and nitrogen oxides generated after the explosion of each kilogram of explosive is calculated according to formula (5) and (6) respectively. =V×
V\= V. × P
Where: V!
The volume of carbon monoxide generated after the explosion of each kilogram of explosive, L/kg; V. The volume of gas generated after the explosion of each kilogram of explosive under standard conditions, L/kg; 9
The volume fraction of carbon monoxide in the gas sample, %; -The volume of nitrogen oxides generated after the explosion of each kilogram of explosive, L/kg; The volume fraction of nitrogen oxides in the gas sample, %. ...( 5)
·(6)
5.3.3 The total amount of toxic gas generated after the explosion of each dry gram of explosive (converted into carbon monoxide under standard conditions) is calculated according to formula (7). V=V+ 6.5V\
Wherein, V-
The total amount of toxic gas generated after the explosion of each kilogram of explosives, L/kg; -The volume of carbon monoxide generated after the explosion of each kilogram of explosives, L/kg; 6.5-The toxicity coefficient when converting nitrogen oxides into carbon monoxide; \-The volume of nitrogen oxides generated after the explosion of each dry gram of explosives, L/kg. Parallel determination is performed twice, and the allowable difference should not exceed 10L/kg. The larger value is taken as the final result and rounded to the nearest digit. (7)Add absorption liquid to the 15mL mark respectively. Then use a pipette to draw 5mL of colorimetric solution and add it to the colorimetric tube. Then, place the colorimetric tube in a constant temperature water bath at 25℃±1℃ and keep it warm for about 30 minutes to make it completely colorized. On the spectrophotometer, use 1cm of colorimetric blood and zero standard solution as reference to measure the absorbance of each standard solution at a wavelength of 545nm. Draw a working curve with the mass of nitrogen dioxide as the horizontal axis and the absorbance as the vertical axis. 5.2.2.4.2 Determination of nitrogen dioxide
Take 40mL of gas sample respectively and inject it into two vacuum sampling bottles containing 15mL of nitrogen dioxide absorption solution. After the gas sample is oxidized and absorbed for 24 hours, it is used for determination.
Accurately draw 5mL of colorimetric solution into the sampling bottle and measure the absorbance with the reagent blank solution as reference according to the method described in 5.2.2.4.1. According to the absorbance, the mass of nitrogen dioxide corresponding to the sample is obtained on the working curve, and then converted into the volume fraction of nitrogen dioxide. 5.2.2.5 Expression of test results
The content of nitrogen oxides in the gas sample is calculated according to formula (3). = a×64×10 × 100
Wherein: 9—
-The volume fraction of nitrogen oxides in the gas sample, %; a—-—The mass of NOz obtained from the working curve, mg; 6.4×10-5——Conversion coefficient, L/mg; V. \—-The volume of the gas sample under standard conditions, L. Parallel determination is performed twice, and the allowable difference should not be greater than 0.3%. The arithmetic mean is taken as the result, and the result is accurate to 0.01%. 5.3 Calculation of the total amount of toxic gas
5.3.1 Under standard conditions, the total volume of gas after explosion per kilogram of explosive is calculated according to formula (4). Ve=
Where: V-
V, × (P. + P, - P, - P,) × 273 × 1 000101.3 X (273 + t)m
-The volume of gas produced after the explosion of each kilogram of explosive under standard conditions, L/kg; (3)
Gas sample preparation method 1 is the actual volume of the explosive shell after deducting the volume occupied by the steel cannon, L; Gas sample preparation method 2 is the actual volume of the explosive shell, L; P.--The pressure difference value of the U-type mercury differential pressure gauge, kPa; P,-The atmospheric pressure during measurement, kPa;
P,The residual pressure in the shell when evacuated, kPa; P
The saturated water vapor pressure of air at temperature t, kPa; 828
GB18098-2000
Conversion constant for absolute temperature and Celsius temperature; Conversion factor for kilogram and gram;
The product of the conversion factor of 0.1333 between millimeters of mercury and kilopascals and the atmospheric pressure of 760 mmHg under standard conditions. Room temperature during measurement, C;
Mass of the test roll, g.
5.3.2 The volume of carbon monoxide and nitrogen oxides generated after the explosion of each kilogram of explosive is calculated according to formula (5) and (6) respectively. =V×
V\= V. × P
Where: V!
The volume of carbon monoxide generated after the explosion of each kilogram of explosive, L/kg; V. The volume of gas generated after the explosion of each kilogram of explosive under standard conditions, L/kg; 9
The volume fraction of carbon monoxide in the gas sample, %; -The volume of nitrogen oxides generated after the explosion of each kilogram of explosive, L/kg; The volume fraction of nitrogen oxides in the gas sample, %. ...( 5)
·(6)
5.3.3 The total amount of toxic gas generated after the explosion of each dry gram of explosive (converted into carbon monoxide under standard conditions) is calculated according to formula (7). V=V+ 6.5V\
Wherein, V-
The total amount of toxic gas generated after the explosion of each kilogram of explosives, L/kg; -The volume of carbon monoxide generated after the explosion of each kilogram of explosives, L/kg; 6.5-The toxicity coefficient when converting nitrogen oxides into carbon monoxide; \-The volume of nitrogen oxides generated after the explosion of each dry gram of explosives, L/kg. Parallel determination is performed twice, and the allowable difference should not exceed 10L/kg. The larger value is taken as the final result and rounded to the nearest digit. (7)Add absorption liquid to the 15mL mark respectively. Then use a pipette to draw 5mL of colorimetric solution and add it to the colorimetric tube. Then, place the colorimetric tube in a constant temperature water bath at 25℃±1℃ and keep it warm for about 30 minutes to make it completely colorized. On the spectrophotometer, use 1cm of colorimetric blood and zero standard solution as reference to measure the absorbance of each standard solution at a wavelength of 545nm. Draw a working curve with the mass of nitrogen dioxide as the horizontal axis and the absorbance as the vertical axis. 5.2.2.4.2 Determination of nitrogen dioxide
Take 40mL of gas sample respectively and inject it into two vacuum sampling bottles containing 15mL of nitrogen dioxide absorption solution. After the gas sample is oxidized and absorbed for 24 hours, it is used for determination.
Accurately draw 5mL of colorimetric solution into the sampling bottle and measure the absorbance with the reagent blank solution as reference according to the method described in 5.2.2.4.1. According to the absorbance, the mass of nitrogen dioxide corresponding to the sample is obtained on the working curve, and then converted into the volume fraction of nitrogen dioxide. 5.2.2.5 Expression of test results
The content of nitrogen oxides in the gas sample is calculated according to formula (3). = a×64×10 × 100
Wherein: 9—
-The volume fraction of nitrogen oxides in the gas sample, %; a—-—The mass of NOz obtained from the working curve, mg; 6.4×10-5——Conversion coefficient, L/mg; V. \—-The volume of the gas sample under standard conditions, L. Parallel determination is performed twice, and the allowable difference should not be greater than 0.3%. The arithmetic mean is taken as the result, and the result is accurate to 0.01%. 5.3 Calculation of the total amount of toxic gas
5.3.1 Under standard conditions, the total volume of gas after explosion per kilogram of explosive is calculated according to formula (4). Ve=
Where: V-
V, × (P. + P, - P, - P,) × 273 × 1 000101.3 X (273 + t)m
-The volume of gas produced after the explosion of each kilogram of explosive under standard conditions, L/kg; (3)
Gas sample preparation method 1 is the actual volume of the explosive shell after deducting the volume occupied by the steel cannon, L; Gas sample preparation method 2 is the actual volume of the explosive shell, L; P.--The pressure difference value of the U-type mercury differential pressure gauge, kPa; P,-The atmospheric pressure during measurement, kPa;
P,The residual pressure in the shell when evacuated, kPa; P
The saturated water vapor pressure of air at temperature t, kPa; 828
GB18098-2000
Conversion constant for absolute temperature and Celsius temperature; Conversion factor for kilogram and gram;
The product of the conversion factor of 0.1333 between millimeters of mercury and kilopascals and the atmospheric pressure of 760 mmHg under standard conditions. Room temperature during measurement, C;
Mass of the test roll, g.
5.3.2 The volume of carbon monoxide and nitrogen oxides generated after the explosion of each kilogram of explosive is calculated according to formula (5) and (6) respectively. =V×
V\= V. × P
Where: V!
The volume of carbon monoxide generated after the explosion of each kilogram of explosive, L/kg; V. The volume of gas generated after the explosion of each kilogram of explosive under standard conditions, L/kg; 9
The volume fraction of carbon monoxide in the gas sample, %; -The volume of nitrogen oxides generated after the explosion of each kilogram of explosive, L/kg; The volume fraction of nitrogen oxides in the gas sample, %. ...( 5)
·(6)
5.3.3 The total amount of toxic gas generated after the explosion of each dry gram of explosive (converted into carbon monoxide under standard conditions) is calculated according to formula (7). V=V+ 6.5V\
Wherein, V-
The total amount of toxic gas generated after the explosion of each kilogram of explosives, L/kg; -The volume of carbon monoxide generated after the explosion of each kilogram of explosives, L/kg; 6.5-The toxicity coefficient when converting nitrogen oxides into carbon monoxide; \-The volume of nitrogen oxides generated after the explosion of each dry gram of explosives, L/kg. Parallel determination is performed twice, and the allowable difference should not exceed 10L/kg. The larger value is taken as the final result and rounded to the nearest digit. (7)
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