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HJ 760-2015 English PDF

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HJ 760-2015: Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography method
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Basic data

Standard ID HJ 760-2015 (HJ760-2015)
Description (Translated English) Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography method
Sector / Industry Environmental Protection Industry Standard
Word Count Estimation 19,173
Date of Issue 2015-10-22
Date of Implementation 2015-12-01
Quoted Standard HJ/T 20; HJ/T 298; HJ/T 299; HJ/T 300
Regulation (derived from) ?Ministry of Environment Protection Bulletin 2015 No.62
Issuing agency(ies) Ministry of Ecology and Environment
Summary This standard specifies the headspace of solid waste in volatile organic compounds - Gas Chromatography. This standard applies to solid waste leachate of solid wastes and the determination of 37 volatile organic compounds.

HJ 760-2015: Solid waste. Determination of volatile organic compounds. Headspace-gas chromatography method


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Solid waste.Determination of volatile organic compounds.Headspace-gas chromatography method National Environmental Protection Standard of the People's Republic Determination of volatile organic compounds in solid waste Headspace-gas chromatography Solid waste-Determination of volatile organic compounds - Headspace-gas chromatography method Published on.2015-10-22 2015-12-01 Implementation Ministry of Environmental Protection release i directory Foreword... II 1 Scope of application ... 1 2 Normative references... 1 3 Principles of the method ... 1 4 Reagents and materials... 1 5 Instruments and Equipment... 2 6 Samples... 2 7 Analysis steps... 4 8 Results Calculation and Representation... 9 Precision and Accuracy... 10 Quality Assurance and Quality Control... 11 废物处理...7 12 Precautions...7 Appendix A (Normative) The detection limit and the lower limit of the measurement method...9 Appendix B (informative) The precision and accuracy of the method... 11

Foreword

To implement the Environmental Protection Law of the People's Republic of China and the Law of the People's Republic of China on the Prevention and Control of Environmental Pollution by Solid Waste This standard is formulated to protect the environment, protect human health, and regulate the determination of volatile organic compounds in solid waste. This standard specifies headspace-gas chromatography for the determination of volatile organic compounds in solid waste. This standard is the first release. Appendix A of this standard is a normative appendix, and Appendix B is an informative appendix. This standard was formulated by the Science and Technology Standards Department of the Ministry of Environmental Protection. This standard is mainly drafted by. Anshan Environmental Monitoring Center Station. This standard is verified by. Liaoning Provincial Environmental Monitoring Experimental Center, Shenyang Environmental Monitoring Center Station, Dalian Environmental Monitoring Center, Harbin Environmental Monitoring Center Station, Fushun Environmental Monitoring Center Station and Liaoyang Environmental Monitoring Station. This standard was approved by the Ministry of Environmental Protection on October 22,.2015. This standard has been implemented since December 1,.2015. This standard is explained by the Ministry of Environmental Protection. 1 Determination of volatile organic compounds in solid waste - Headspace - gas chromatography Warning. The reagents and standard solutions used in the test are volatile toxic compounds. The preparation process should be in the fume hood. Carry out the operation; wear protective equipment as required to avoid contact with skin and clothing.

1 Scope of application

This standard specifies headspace-gas chromatography for the determination of volatile organic compounds in solid waste. This standard applies to the determination of 37 volatile organic compounds in solid waste and solid waste leachate. Other volatility If the machine is verified, it is also applicable to this standard. When the amount of solid waste sample is 2 g, the detection limit of 37 target methods is 0.003 mg/kg ~ 0.04 mg/kg. The lower limit is 0.02 mg/kg ~ 0.2 mg/kg. Method detection limit for 37 targets when the volume of solid waste leachate is 10 ml The measurement limit is from 0.6 μg/L to 10.2 μg/L, and the lower limit of measurement is from 2.4 μg/L to 40.8 μg/L. See Appendix A for details.

2 Normative references

The contents of this standard refer to the following documents or their terms. For undated references, the valid version is appropriate. Used in this standard. HJ/T 20 Technical Specifications for Sampling and Sample Preparation of Industrial Solid Waste HJ/T 298 Hazardous Waste Identification Technical Specification HJ/T 299 solid waste leaching toxicity leaching method sulfuric acid nitric acid method HJ/T 300 solid waste leaching toxicity leaching method acetic acid buffer solution method

3 Principle of the method

At a certain temperature, the volatile organic compounds in the sample in the headspace bottle volatilize into the liquid space, generating vapor pressure, in the gas and liquid. After the solid three-phase reaches the thermodynamic equilibrium, the volatile organic compounds in the gas phase are separated by gas chromatography and detected by flame ionization. Detection. Characterize by retention time and quantify by external standard method.

4 reagents and materials

4.1 Experimental water. double distilled water or water prepared by ultrapure water meter. A blank test is required before use to confirm There is no interference peak in the retention time interval of the standard. 4.2 Methanol (CH3OH). pesticide residue level or equivalent. Confirm by the blank test within the retention time interval of the target No interference peaks appear. 4.3 Sodium chloride (NaCl). excellent grade pure. Burn in a muffle furnace (or box furnace) at 400 ° C for 4 h, place in a desiccator and cool to room temperature, transfer to the ground glass Store in a glass bottle. 4.4 Phosphoric acid (H3PO4). excellent grade pure. 4.5 Saturated sodium chloride solution Measure 500 ml of experimental water (4.1), add a few drops of phosphoric acid (4.4) to adjust pH ≤ 2, add 180 g of sodium chloride (4.3), Dissolve and mix. Store at 4 ° C for 6 months. 4.6 Standard stock solution. ρ = 1 000 mg/L ~ 5 000 mg/L. 2 can directly purchase certified standard solution, can also be prepared with standard materials. 4.7 Standard use solution. ρ=10 mg/L～100 mg/L. The standard use solution of the target is stored in a compact bottle with a shelf life of one month or prepared according to the manufacturer's instructions. 4.8 Quartz sand. analytically pure. 20 mesh ~ 50 mesh. Before use, it is necessary to pass the test to confirm that the concentration of the target compound or target compound is lower than the method detection limit. 4.9 Carrier gas. High-purity nitrogen (≥99.999%), deoxidized by deoxidizer and dehydrated by molecular sieve. 4.10 Gas. High purity hydrogen (≥99.999%), dehydrated by molecular sieve. 4.11 Gas-assisted gas. air, dehydrated by silica gel and deactivated by activated carbon. Note 1. All the above standard solutions are treated with methanol as the solvent. The standard solution after preparation or unsealing should be placed in a compact bottle, and protected from light under 4 °C. The storage period is generally 30 days. Recover to room temperature and mix before use.

5 Instruments and equipment

5.1 Gas Chromatograph. with capillary column split/splitless inlet, programmable temperature, flame ionization detector (FID). 5.2 Column. Quartz capillary column, column 1. 60 m × 0.25 mm, film thickness 1.4  m (6% nitrile propyl, 94% dimethyl Other polysiloxane columns can also be used. Column 2. 30 m × 0.32 mm, film thickness 0.25 m (poly Ethylene glycol 20 M), other equivalent capillary columns can also be used. 5.3 Automatic Headspace Sampler. Headspace Bottle (22 ml), Gasket (Teflon/Siloxane), Cap (Spiral Cover or One) The gland used for the second time). 5.4 Reciprocating Oscillator. The oscillation frequency is 150 times/min, which can fix the headspace bottle. 5.5 Balance. Accuracy is 0.01 g. 5.6 Sampling bottle. 60 ml or.200 ml threaded brown wide-mouth glass bottle with Teflon-silica liner screw cap. 5.7 Sampling equipment. shovel and stainless steel medicine spoon. 5.8 Portable refrigerator. 20 L, temperature 4 ° C or less. 5.9 Disposable Pasteur glass pipettes. 5.10 Microinjectors. 5 μl, 10 μl, 25 μl, 100 μl, 500 μl, 1000 μl. 5.11 Brown compact bottle. 2 ml with Teflon liner and solid screw cap. 5.12 Common instruments and equipment used in general laboratories.

6 samples

6.1 Sample collection and preservation 6.1.1 Collect and store solid waste samples in accordance with the relevant provisions of HJ/T 20 and HJ/T 298. Collecting samples With a shovel and stainless steel medicine spoon (5.7). At least 3 representative samples should be collected for all samples. 6.1.2 Use a shovel and stainless steel spoon (5.7) to collect the sample into the sample bottle (5.6) as soon as possible and fill it as much as possible. Quick clear Remove the sample from the sample bottle (5.6) and the adhered sample on the outer surface and seal the sample bottle (5.6). Placed in a portable freezer (5.8) Brought back to the laboratory. 6.1.3 Samples should be analyzed as soon as they are sent to the laboratory. If it can not be analyzed immediately, it should be sealed and protected from light at 4 °C, and the storage period should be saved. The limit is no more than 14 days. The sample storage area should be free of organic interference. Note 2. When the concentration of volatile organic compounds in the sample is greater than 1 000 μg/kg, the sample is regarded as a high content sample. Note 3. Do not stir solid waste during sample collection to avoid volatilization of organic matter in solid waste. 3 Note 4. If necessary, the sample can be screened at a high concentration and low concentration using a portable instrument for the determination of volatile organic compounds. 6.2 Preparation of samples 6.2.1 Low-volume samples of solid waste Take out the sample bottle (5.6) in the laboratory. After returning to room temperature, weigh 2 g (accurate to 0.01 g) and place the sample in the headspace. In a bottle (22 ml), quickly add 10.0 ml of saturated sodium chloride solution (4.5) to the headspace bottle (22 ml) and seal immediately. Oscillating at 150 times/min for 10 min on a reciprocating oscillator (5.4), to be tested. 6.2.2 High-volume samples of solid waste If the initial screening of volatile organic compounds at the site is high or low, the results are greater than 1 000 μg/kg. It is a high content sample. The high content sample is prepared as follows. Take out the sample bottle (5.6), and after returning to room temperature, weigh 2 g (fine As far as 0.01 g), the sample was placed in a headspace vial (22 ml) and 10.0 ml of methanol (4.2) was quickly added to the headspace vial (22 ml). Immediately sealed and oscillated on a reciprocating oscillator (5.4) at a frequency of 150 times/min for 10 min. After standing still, use Dispense approximately 1 ml of the extract into a 2 ml brown compact bottle (5.11) in a disposable Pasteur glass pipette (5.9). The extraction The solution can be stored in a freezer at 4 ° C for a period of 14 days. After returning the extract to room temperature before analysis, add 2 g (accurate to 0.01 g) to an empty headspace vial (22 ml) Quartz sand (4.8), 10.0 ml saturated sodium chloride solution (4.5) and 0.010 to 0.100 ml methanol extract. Seal immediately, Oscillating at 150 times/min for 10 min on a reciprocating oscillator (5.4), to be tested. Note 5. If the concentration of volatile organic compounds in the methanol extract is high, it can be diluted appropriately by adding methanol. Note 6. If the concentration value is too low or not detected by the high content method, the sample should be re-analyzed using the low content method. 6.2.3 Solid waste leachate sample Weighing a solid waste sample with a dry basis mass of 40-50 g, and preparing a solid waste water leaching solution according to the HJ/T 299 method Sample, weigh the dry basis mass of 20 ~ 25 g solid waste, according to HJ/T 300 method to prepare solid waste acetic acid leaching solution Sample. Transfer 10.0 ml of the leachate into the headspace bottle (22 ml) and seal immediately for testing. 6.3 Preparation of blank samples 6.3.1 Blank sample for solid waste transportation 10.0 ml of saturated sodium chloride solution (4.5) and 2 g (accurate to 0.01 g) of quartz sand (4.8) in the laboratory before sampling Place in a headspace bottle (22 ml) and seal it to the sampling site. The sample is not opened when it is sampled, and then shipped back to the laboratory with the sample. Oscillating at 150 times/min for 10 min on a reciprocating oscillator (5.4), to be tested. 6.3.2 Low content blank sample of solid waste Weigh 2 g (accurate to 0.01 g) quartz sand (4.8) instead of low-level sample, and prepare low-level empty according to step 6.2.1. White sample. 6.3.3 Solid waste high content blank sample Weigh 2 g (accurate to 0.01 g) of quartz sand (4.8) instead of high-content samples, and prepare high-content empty according to the procedure of 6.2.2. White sample. 6.3.4 Blank sample of solid waste leaching solution According to the extraction method of HJ/T 299 or HJ/T 300, take 10.0 ml of leaching agent into the headspace bottle and seal immediately. Measurement. 47 Analysis steps 7.1 Instrument Reference Conditions Different models of headspace sampler and gas chromatograph have different working conditions, and should be operated according to the instrument manual. Work. The reference conditions for the recommended instruments of this standard are as follows. 7.1.1 Headspace Sampler Reference Conditions Heating equilibrium temperature 85 ° C; heating equilibrium time 50 min; sampling needle temperature 100 ° C; transmission line temperature 110 ° C; The transmission line is a deactivated quartz capillary column with an inner diameter of 0.32 mm; the pressure equalization time is 1 min; the injection time 0.2 min; the needle removal time was 0.4 min. Note 7. Other injection methods are also available. 7.1.2 Gas Chromatograph Reference Conditions Temperature programmed. 40 ° C (for 5 min) 8 ° C/min 100 ° C (for 5 min) 6 ° C/min.200 ° C (maintained 10 min); inlet temperature. 220 ° C; detector temperature. 240 ° C; carrier gas. nitrogen; column flow. 1.0 ml/min; Hydrogen flow rate. 45 ml/min; air flow rate. 450 ml/min; injection method. split injection; split ratio. 10.1. 7.2 Calibration curve drawing 7.2.1 Drawing of calibration curve for solid waste Add 2 g (accurate to 0.01 g) quartz sand (4.8) and 10.0 ml to 5 headspace bottles (22 ml). And sodium chloride solution (4.5), then add a certain amount of standard use solution (4.7) to each bottle, seal immediately, and configure the target The mass of the compound was a 5-point calibration curve series of 0.10 μg, 0.20 μg, 0.50 μg, 1.00 μg, and 2.00 μg, respectively. Will match The sample of the set calibration curve was oscillated on the reciprocating oscillator (5.4) at a frequency of 150 times/min for 10 min. According to the instrument reference conditions (7.1), the sample is injected in sequence, with the peak area or peak height as the ordinate and the mass (μg) as the abscissa. Draw a calibration curve. 7.2.2 Calibration curve of solid waste leachate Add 10.0 ml of extractant to 5 headspace bottles (22 ml), and add a certain amount of standard use to each bottle. Liquid (4.7), immediately sealed, with target compounds of 10.0 μg/L, 20.0 μg/L, 50.0 μg/L, 100 μg/L, and A 5-point calibration curve series of.200 μg/L. Inject the sample according to the instrument reference conditions (7.1), with peak area or peak height. For the ordinate, the concentration (μg/L) is plotted on the abscissa and a calibration curve is drawn. 7.3 Determination Place the prepared sample (6.2) on the automatic headspace sampler (5.3) and follow the instrument reference conditions (7.1). Determination. 7.4 Blank test Place the prepared blank sample (6.3) on the automatic headspace sampler (5.3) according to the instrument reference conditions (7.1) The measurement was carried out.

8 Calculation and representation of results

8.1 Qualitative analysis Prepare a standard solution with a target concentration of 0.200 mg/L. Separate using column 1 and follow the automatic headspace. The sampler and gas chromatograph are measured with reference conditions to characterize retention time. Column 1 Standard for Analysis of Volatile Organic Compounds The chromatogram is shown in Figure 1. The standard chromatogram of column 2 for the analysis of volatile organic compounds is shown in Figure 2. When using this method is not qualitative, 5 can be aided by column 2 or GC/MS. 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 min 0.0 1.0 2.0 3.0 4.0 5.0μV (x10,000) chromatography 1-chloroethylene; 2-1,1-dichloroethylene; 3-dichloromethane; 4-trans-1,2-dichloroethylene; 5-1,1-dichloroethane; 6-cis-1, 2-dichloroethylene; 7-chloroform; 8-1,1,1-trichloroethane; 9-carbon tetrachloride; 10-1,2-dichloroethanebenzene; 11-trichloroethylene; 12-1,2-dichloro Propane; 13-bromo Dichloromethane; 14-toluene; 15-1,1,2-trichloroethane; 16-tetrachloroethylene; 17-dibromochloromethane; 18-1,2-dibromoethane; 19-chloro Benzene; 20-1,1,1,2-tetrachloroethane; 21-ethylbenzene; 22-m-xylene p-xylene; 23-o-xylene styrene; 24-bromoform; 25-1 ,1,2,2- Tetrachloroethane; 26-1,2,3-trichloropropane; 27-1,3,5-trimethylbenzene; 28-1,2,4-trimethylbenzene; 29-1,3-di Chlorobenzene; 30-1,4-dichlorobenzene; 31-1,2-dichlorobenzene; 32-1,2,4-trichlorobenzene; 33-hexachlorobutadiene; 34-naphthalene Figure 1 Column 1 analysis of 37 volatile organic compounds standard chromatogram 1-chloroethylene; 2-cis-1,2-dichloroethylene 1,1-dichloroethylene; 3-trans-1,2-dichloroethylene; 4-carbon tetrachloride 1,1,1-trichloro Ethane; 5-1, 1- Dichloroethane; 6-dichloromethane; 7-benzene; 8-trichloroethylene; 9-tetrachloroethylene; 10-chloroform; 11-toluene; 12-1,2-dichloropropane; - Dichloroethane; 14-ethylbenzene; 15-p-xylene; 16-m-xylene; 17-bromodichloromethane; 18-o-xylene; 19-chlorobenzene; 20-1,3,5 - Trimethylbenzene; 21-1,2-dibromoethane; 22-styrene; 23-1,1,1,2-tetrachloroethane; 24-1,2,4-trimethylbenzene 1, 1,2-trichloroethane; 25- Dibromochloromethane; 26-1,3-dichlorobenzene; 27-1,4-dichlorobenzene; 28-bromoform; 29-1,2,3-trichloropropane; 30-1,2-di Chlorobenzene; 31-hexachloro Butadiene; 32-1,1,2,2-tetrachloroethane; 33-1,2,4-trichlorobenzene; 34-naphthalene Figure 2 Column 2 analysis of 37 volatile organic compounds standard chromatograms 5.0 10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 min 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 μV (x1,000) 68.2 Quantitative analysis The target compound was detected using a flame ionization detector and quantified by external standard method. Volatile organic content in the sample according to the formula (1) Calculate with equation (2). 8.3 Calculation of results of volatile organic compounds in solid waste 8.3.1 The content of volatile organic compounds (mg/kg) in low-content solid waste is calculated according to formula (1). M (1) Where. --the content of the target compound in the sample, mg/kg; M0 - calculate the mass of the target compound based on the calibration curve, μg; M1 - sample size (wet weight), g. 8.3.2 The content of volatile organic compounds (mg/kg) in high-content solid waste is calculated according to formula (2). SV Fm  0.10 (2) Where. --the content of the target compound in the sample, mg/kg; M0--calculate the mass of the target compound according to the calibration curve, μg; 10.0 - extract volume, ml; M1--sample amount (wet weight), g; Vs--the volume of methanol extract used for headspace determination, ml; f - dilution factor of the extract. 8.3.3 Calculation of results of volatile organic compounds in solid waste leachate When measuring solid waste leachate samples, the concentration of volatile organic compounds was directly determined from the calibration curve and expressed in μg/L. 8.4 Results The number of decimal places and the method detection limit are consistent, and up to three significant digits are reserved.

9 Precision and accuracy

9.1 precision Six laboratories were fixed at concentrations of 0.25 mg/kg (0.1 mg/kg) and 1.0 mg/kg (0.5 mg/kg), respectively. The body waste samples were tested for precision. The relative standard deviations in the laboratory ranged from 1.5% to 38.9%. 1.1%~32.2%; the relative standard deviations between laboratories are. 5.1%~26.8%, 1.5%~29.8%; repeatability limit The ranges are. 0.008 mg/kg to 0.05 mg/kg, 0.06 mg/kg to 0.3 mg/kg; the reproducibility limits are. 0.008 Mg/kg to 0.1 mg/kg, 0.06 mg/kg to 0.4 mg/kg. Six laboratories for solid waste at concentrations of 50 μg/L (20 μg/L) and.200 μg/L (100 μg/L) The water leaching samples were tested for precision. The relative standard deviations in the laboratory ranged from 1.0% to 9.9%. 0.7%~9.2%; the relative standard deviations between laboratories are. 0.3%~15.1%, 0.1%~9.1%; repeatability limit The circumference is. 1.2 μg/L to 6.5 μg/L, 4.1 μg/L to 22.6 μg/L; the reproducibility limits are. 27.6 μg/L to 104 Gg/L, 146 μg/L to 447 μg/L. Six laboratories for solid waste at concentrations of 50 μg/L (20 μg/L) and.200 μg/L (100 μg/L) The sample of acetic acid leaching solution was tested for precision. The relative standard deviations in the laboratory ranged from 1.1% to 9.8%. 0.5%~9.7%; the relative standard deviations between laboratories are. 0.02%~13.5%, 0.8%~20.7%; repeatability limit The ranges are. 1.5 μg/L to 7.3 μg/L, 2.8 μg/L to 24.7 μg/L; the reproducibility limits are. 28.7 μg/L~ 105 μg/L, 138 μg/L to 428 μg/L. 9.2 Accuracy Six laboratories tested the solid waste matrix spiked sample with a spiked sample content of 0.25 mg/kg (0.10). Mg/kg), the recovery rate of the corresponding target of 37 kinds of target is 13.0%~116%; the spiked content of the sample is 1.0 mg/kg (0.5) Mg/kg), the recovery rate of the corresponding target of 37 kinds of target is 13.0%~106%. Six laboratories tested the spiked sample of solid waste water leaching matrix with a spiked sample content of 50 μg/L (20 Μg/L), the recovery of the corresponding target of 37 kinds of target ranged from 90.7% to 108%; the sample spiked content was.200 μg/L (100 Μg/L), the recoveries of the corresponding targets for the 37 targets ranged from 98.5% to 108%. Six laboratories tested the spiked sample of solid waste acetic acid leaching solution with a spiked sample content of 50 μg/L (20 Μg/L), the recoveries ranging from 37 targets to the target ranged from 93.1% to 110%; the sample spiked at.200 μg/L (100) Μg/L), the recovery rate of the corresponding target of 37 kinds of targets is 89.2%~105%. The summary data of precision and accuracy is detailed in Appendix B. 10 Quality Assurance and Quality Control 10.1 Calibration curve A calibration curve is drawn according to the concentration and response value of the target, and the correlation coefficient should be greater than 0.99. If the requirements are not met, Replace the column or take other measures and redraw the calibration curve. 10.2 Calibration Confirmation Before each batch of samples is analyzed or within 24 h, the calibration is confirmed by the intermediate concentration point of the standard curve. The relative deviation between the measured value and the standard value should be ≤ 20%. Otherwise, the calibration curve should be redrawn. 10.3 Sample 10.3.1 All the targets to be tested in the laboratory blank test analysis results.

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