GB/T 19277.2-2013 English PDF (GBT19277.2-2013)
GB/T 19277.2-2013 English PDF (GBT19277.2-2013)
GB/T 19277.2-2013: Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions -- Method by analysis of evolved carbon dioxide -- Part 2: Gravimetric measurement of carbon dioxide evolved in a laboratory-scale test
Determination of the ultimate aerobic biodegradability of plastic materials under controlled composting conditions - Method by analysis of evolved carbon dioxide - Part 2. Gravimetric measurement of carbon dioxide evolved in a laboratory-scale test ICS 83.080.01
National Standards of People's Republic of China
Final aerobic organisms under controlled composting conditions
Method of carbon dioxide Part 2. Weight
Analytical method for the determination of carbon dioxide under laboratory conditions Release amount
evolvedcarbondioxide-Part 2. Gravimetricmeasurementof
(ISO 14855-2.2007, IDT)
2013-09-06 released.2014-01-31 implementation
General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China China National Standardization Administration issued
GB/T 19277 "Determination of the final aerobic biodegradability of materials under controlled composting conditions using the method of determining the released carbon dioxide The Law is divided into the following sections.
--- Part 1. General method;
--- Part 2. Determination of carbon dioxide emissions under laboratory conditions by gravimetric analysis. This part is the second part of GB/T 19277.
This part is drafted in accordance with the rules given in GB/T 1.1-2009. This section uses the translation method equivalent to the ISO 14855-2.2007 "measurement of the final aerobic biodegradability of materials under controlled composting conditions" Methods of determining the release of carbon dioxide - Part 2. Determination of carbon dioxide release under laboratory conditions by gravimetric method the amount".
The documents of our country that have a consistent correspondence with the international documents referenced in this part are as follows. ---GB/T 19277.1-2011 Determination of the final aerobic biodegradability of materials under controlled composting conditions Methods of carbon dioxide Part 1. General methods (ISO 14855-1.2005, IDT). This part is under the jurisdiction of the National Biomaterials and Degradation Products Standardization Technical Committee (SAC/TC380). This section drafted by. Suzhou Hanfeng New Materials Co., Ltd., Beijing Technology and Business University Light Industrial Plastics Processing Application Research Institute, Shenzhen City Dajie Plastic Products Co., Ltd., National Plastic Products Quality Supervision and Inspection Center (Beijing). The main drafters of this section. Yan Yujuan, Jiang Kai, Huang Xiangqiu, Chen Mingxing, Wei Wenchang, Li Ziyi. introduction
Waste plastics management is a serious problem worldwide. Plastic recycling technology includes material recovery (mechanical recycling, chemical or Crude recovery, biological or organic recovery) and energy recovery (thermal, steam or electrical energy as a substitute for fossil fuels and other fuel resources). The use of biodegradable plastics is a valuable option for recycling (biological or organic recycling). Some international standards for measuring the ultimate aerobic/anaerobic biodegradability of plastics have been published. In particular, ISO 14855-1 is adopted The use of continuous infrared analysis, gas chromatography or titration to determine the amount of carbon dioxide released is a common test method. ISO 14855- 1.2005 has been equivalently adopted as China's standard GB/T 19277.1-2011. Compared with GB/T 19277.1-2011, this part makes The ratio of compost inoculum to test sample used was 1.10. In order to ensure the activity of the compost inoculum, inert materials are mixed into the inoculum. In order to give the mixture the same texture as the soil. The amount of carbon dioxide released from the experimental container is measured by a carbon dioxide absorption device, The absorbent is then subjected to gravimetric analysis. ISO 14855 uses a closed system to collect the released carbon dioxide, which can be determined by isotope calibration Research has obtained useful information, including the way in which the molecular structure of the copolymer is decomposed. WARNING. Wastewater, activated sludge, soil, and compost may contain potential pathogens, so appropriate precautions should be taken when handling. Special care must be taken when handling toxicity test compounds or compounds of unknown nature. Final aerobic organisms under controlled composting conditions
Method of carbon dioxide Part 2. Weight
Analytical method for the determination of carbon dioxide under laboratory conditions Release amount
This part of GB/T 19277 specifies a test method for determining the discharge of a material under controlled composting conditions. The amount of carbon dioxide is used to determine its ultimate aerobic biodegradability. This method regulates the humidity, aerobic concentration and temperature in the compost container Equal conditions to achieve the best rate of biodegradation.
This section applies to the following materials.
--- natural and/or synthetic polymers, copolymers and mixtures thereof; ---Plastics containing additives such as plasticizers and pigments;
---Water soluble polymer;
--- Materials that do not inhibit microbial activity in the inoculum under the experimental conditions. If the test material has an inhibitory effect on the microorganisms in the inoculum, other types of compost compost or pre-exposure compost can be used. 2 Normative references
The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article. Pieces. For undated references, the latest edition (including all amendments) applies to this document. ISO 5663 Water quality-Determination
ISO 8245 Water quality-Guidelines for the determination of total organic carbon (TOC) and dissolved organic carbon (DOC) in water quality ISO 14855-1 Determination of the ultimate aerobic biodegradability of materials under controlled composting conditions - Part 1. General method 3 Terms and definitions
The following terms and definitions apply to this document.
An organic soil conditioner obtained by biological decomposition of the mixture. The mixture consists mainly of plant residues and sometimes some organic materials. Material and certain inorganic substances.
An aerobic treatment method that produces compost.
Total dry solids totaldrysolids
A known volume of material or compost is dried to a constant amount of solids at a temperature of 105 °C. 3.4
Volatile solid volatilesolids
The difference between the total dry solids of a known volume of material or compost minus the amount of residual solids obtained after incineration at a temperature of 550 °C. Note. The volatile solids content is used to characterize the organic content of the material. 3.5
Ultimate aerobic biodegradation ultimateaerobicbiodegradation
Under aerobic conditions, organic compounds are decomposed by microorganisms into carbon dioxide (CO2), water (H2O) and mineralized inorganic salts of the elements contained therein. And new biomass.
Theoretical release of carbon dioxide theoreticalamountofevolvedcarbondioxide m(ThCO2)
The theoretical maximum value of carbon dioxide that can be generated when the test material is completely oxidized can be calculated from the molecular formula to test per gram or milligram. The number of milligrams of carbon dioxide released by the material is expressed in mg/g or mg of test material. 3.7
From the beginning of the test until the microorganisms adapt (or selected) the decomposition products, and the degree of biodegradation of the test materials has increased to the maximum The number of days required for a biodegradation rate of 10%.
Maximum biological decomposition rate maximumlevelofbiodegradation
In the test, the extent to which the test material no longer biodegraded during biodegradation is expressed as a percentage. 3.9
The number of days from the end of the lag phase to 90% of the maximum biodegradation rate. 3.10
Stationary stage plateauphase
The number of days from the end of the biodegradation phase to the end of the trial. 3.11
In order to improve the ability of the inoculum to biodegrade test materials by adapting (selecting) microorganisms, docking in the presence of test materials in the test The seeds are pre-cultured.
In order to improve the test results of the microorganisms in the test environment, the inoculum is pre-tested in the absence of test materials in subsequent tests. to cultivate.
Water holding rate water-holdingcapacity;WHC
The quality of water evaporated from water-saturated soil, ie the mass of water when the soil is dried at constant temperature at 105 ° C to constant weight divided by the dry soil quality.
The method determines the biodegradation rate of the test material under the condition of composting compost by controlling the humidity, oxygen rate and temperature of the compost container rate. The method is also directed to the use of a small reactor to determine the final biodegradability of the test material. By weighing sodium lime and sodium talc The absorption device measures the amount of carbon dioxide released to periodically calculate the calculated decomposition rate. The test material is a mixture of an inoculum from decomposed compost and an inert material such as sea sand. Sea sand in terms of moisturizing and maintaining biological activity Play an active role. See Appendix A and Appendix B for examples of suitable test methods. Regularly weigh the amount of carbon dioxide released with an electronic balance for The next method measures the carbon dioxide content. See Appendix C for the derivation formula for calculating the biodegradation rate from the amount of carbon dioxide released. In the method, The biodegradation rate of the material is obtained by comparing the amount of carbon dioxide released with the theoretical release of carbon dioxide [m(ThCO2)] (in percentage table) Show).
The test is terminated when the biodegradation reaches a stationary phase. The standard time for termination is 45d, but the trial can last up to 180d. 5 reagent
Use analytical grade reagents. Use deionized water.
5.1 Soda lime, used to absorb carbon dioxide, with a particle size of 2mm~4mm. 5.2 Anhydrous calcium chloride, used to absorb water, with a particle size of 2mm~3mm. 5.3 Talc powder filled with sodium hydroxide (commonly called sodium talc), used to absorb carbon dioxide, with a particle size of 2mm~3mm. 5.4 Silica gel (including hygrometer) for absorbing water with a particle size of 2mm~4mm. 5.5 Sea sand, particle size from 0.169cm to 0.224cm (20 mesh ~ 35 mesh). 5.6 Reference material. Thin-layer chromatography (TLC) microcrystalline cellulose was used as a positive control reference material with a particle size of less than 20 μm. 6 instruments
Make sure all the utensils are completely cleaned, especially if they are not attached to any organic or toxic substances. 6.1 Gas supply system
It is capable of delivering carbon dioxide-free, water-saturated air to each compost container. The air is compressed by air through the sodium and lime Obtained after the carbon dioxide absorber and humidifier (see Appendix A and Appendix B for examples). Air flow is controlled by the flow meter to provide charge The aerobic conditions of the points.
6.2 Compost container
A bottle or column container is used to ensure the supply of saturated water and carbon dioxide free air in the components. The optimum volume is 500mL. If you try If the test requires the determination of the mass loss of the test material, the empty weight of each compost container shall be weighed. 6.3 Analytical instrument for the determination of carbon dioxide
The instrument can directly measure the amount of carbon dioxide according to the change in the mass of the carbon dioxide absorption device. Carbon dioxide absorption device is filled A container of sodium lime, sodium talc and anhydrous calcium chloride. The container filled with calcium chloride is preferably divided into a container filled with sodium lime and sodium talc. On (see Appendix A and Appendix B for examples). Between the compost container and the carbon dioxide absorption device, an ammonia absorption device (dilute sulfuric acid) and water suction are required. Receiving device (silica gel and calcium chloride).
6.4 airtight tube
Used to connect compost containers with air systems and carbon dioxide measurement systems. 6.5 pH meter
Used to determine the pH of the test mixture. Its accuracy is not more than 0.1. 6.6 Analytical equipment
Used to determine dry solids (at 105 ° C), volatile solids (at 550 ° C) and total organic carbon (TOC) for elemental analysis of materials. When necessary, it is also necessary to determine dissolved inorganic carbon (DIC), volatile fatty acids, air oxygen content, water content, and total nitrogen content. 6.7 balance
Used to periodically measure the mass of the carbon dioxide absorber (to measure the amount of carbon dioxide released), as well as to hold compost and test materials The quality of the compost container. It is recommended to use an electronic balance with a top loading display accuracy of 10 mg and a range of 500 g. 6.8 thermostatic control unit
It is used to ensure that the temperature of the compost container is controllable during the test (see Appendix A and Appendix B for examples). The temperature of the compost container should be maintained at a constant The setting is ±2 °C.
6.9 Compost bioreactor
Covered boxes of polypropylene or other materials can be used as compost bioreactors, and the box size should be such as to facilitate agitation of the components. Use with cover The box avoids excessive evaporation of water. Three holes with a diameter of 10 mm were struck at equal intervals along the center line of the cover. Through these 3 holes, the cabinet can be made The outside gas is exchanged and excess water is gradually evaporated.
7 test steps
7.1 Preparation of inoculum
A fully aerated compost produced by a normally operating aerobic composting unit can be used as an inoculum. The inoculum should be uniform and free of large inertia Substances such as glass, stone, and metal. After removing these impurities by hand, the compost was screened with a sieve having a pore size of 3 mm. Composting can be obtained as follows. Use shavings, sawdust, mushroom beds, chaff or straw as a carbon source. Adding livestock manure as a compost And mineralized inorganic salt nutrient sources. The above materials were placed in a container having a volume of about 1 m3 and mixed well. Carbon to nitrogen ratio required for composting (C/N) is 15, and the carbon to phosphorus ratio (C/P) is 30. When the phosphorus content is insufficient, it can be supplemented with calcium superphosphate. Add water to make the moisture content 65%. C/N, C/P and moisture content can be adjusted to appropriate values based on seasonal variations and climate differences. Composting from the container every week Remove and refill the compost and replenish it as needed before refilling the compost into the container and continuing the test. The best time to use compost is 60d~120d.
Unexposed inoculants are generally used, especially in standard trials that simulate biodegradation behavior in real composting equipment. Sometimes pre-exposure compost can also be used depending on the purpose of the test, as long as it is clearly stated in the test report (eg percentage of biodegradation = X%, using pre-exposure compost), and the pre-exposure method is detailed in the test report. The total amount of total dry solids and volatile solids in the compost inoculum was determined. The total dry solids should be 35% to 55% of the amount of wet solids. The amount of volatile solids exceeds 30% of the dry solids. If necessary, add water before using compost, or perform proper drying (such as drying) The air is aerated to the compost to adjust the moisture content appropriately. Prepare a mixture of 1 part of inoculum and 5 parts of deionized water, and shake them thoroughly to measure the pH immediately. The value should be 7.0~ 9.0.
In order to further characterize the inoculum, some suitable parameters, such as total organic, can be selectively determined at the beginning and at the end of the experiment. Carbon, total nitrogen or fatty acid content.
The inoculum activity was tested by biodegrading the reference material during the test and then measuring the carbon dioxide released from the blank container. Trying At the end of the test, the reference material should be decomposed by at least 70%. Within 10 days of the start of the test, the inoculum in the blank container is relatively volatile per gram. The carbon dioxide produced by the body is about 50mg~150mg. If the amount of carbon dioxide released is too high, the compost should be aerated for a few days and reused for new Test.
7.2 Preparing the sea sand
Soak the sea sand in tap water. Remove floating impurities by precipitation, fully rinse the sea sand, drain the water and keep it at around 105 °C Dry it.
Note. Sea sand is an inert substance with a SiO2 content of more than 90%. It plays an important role in maintaining proper moisture content and supporting microbial growth. 7.3 Preparation of test materials and reference materials
Determination of total organic carbon (TOC) of test materials and reference materials in accordance with ISO 8245, grams of total organic carbon per gram of total dry solids To represent. Alternatively, if the material does not contain inorganic carbon, its carbon content can be determined by elemental analysis. The test material should contain enough Machine carbon to produce the carbon dioxide needed for the determination. Typically 10 g of total dry solids per container contains at least 4 g of total organic carbon. The test material is preferably in the form of a powder, but it is also possible to use a small piece of film or a fragment of a shaped article. The recommended maximum particle size is 250 μm.
7.4 Start the test
Prepare at least the following number of compost containers.
a) 2 test containers (VT) containing the test mixture;
b) 2 blank containers (VB);
c) Two containers (VR) for testing the activity of the inoculum with reference material. The amount of test mixture of test material and inoculum depends on the nature of the test material and the size of the compost container. Total stem of inoculum The total dry solids ratio of solid to test material was approximately 6.1. If an inert material is added, the ratio is not considered. The test mixture should have Have the same moisture content as the inoculum. The moisture content of the test mixture should be set at 80% of the water content of the test mixture (WHC)~ 90%. An inoculum of the same amount of total dry solids should be placed in each test vessel. In a typical test, prepare a 500 mL container with a lid, weigh the inoculum containing 60 g of total dry solids, and add enough water to make the water The content is 65%. Mix well and place the compost at room temperature for 24 h. Weigh 320g of sea sand and add water to make it have a moisture content of 15%. The compost is then mixed evenly with the sea sand as an inert material. 10 g (dry weight) of the test material was added to the mixture and mixed well. Touc...