ISO 20200:2004 pdf free download.Plastics Determination of the degree of disintegration of plastic materials under simulated composting conditions in a laboratory-scale test.
The test method described in ISO 20200 determines the degree of disintegration of plastic materials when exposed to a composting environment. The method is simple and inexpensive, does not require special bioreactors and is scaled for use in any general-purpose laboratory. It requires the use of a standard and homogeneous synthetic solid waste, The synthetic waste components are dry, clean, safe products which can be stored in the laboratory without any odour or health problems. The synthetic waste is of constant composition and devoid of any undesired plastic material which could be erroneously identified as test material at the end of testing. altering the final evaluation. The bioreactors are small, as is the amount of synthetic waste to be composted (approximately 3 I). With the limited amount of test material, this method provides a simplified test procedure. This test method is not aimed at determining the biodegradability of plastic materials under composting conditions. Further testing will be necessary before being able to claim compostability.
I Scope
ISO 20200 spec ifles a method of detemilrng the degree of disintegration of plastic materlats when exposed to a laboratory-scale compoeting environment. The method is not applicable to the determmatlon of the biodegradabibty of plastic materials under composting conditions. Further testing Is necessary to be able to claim composlabibty.
2 NormatIve references
The following referenced documents are Indispensable for the application of ISO 20200. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 3310-12000. Teal sieves — Technical requirements and testing— Part 1: TesS sieves of metal wire cloth
3 Terms and definitions
For the purposes of ISO 20200, the following terms and definitions apply.
compost
organic sod conditioner obtained by biodegradation of a mixture consisting principally of vegetable resue5. occasionally with other organic material and having a united mineral content
32
compostablllly
ability of a material to be biodegreded Wi a compoeting process
NOTE To daidi compos*abullty it mull have been demonstrated that a material can be biodegraded and dientea1ed In a coniposling system (as be atloen by standard test methods) and conwiei., Its biodegradation during the sod-use of the compost. The compost must meet the relevant quality oiteria. Quty criteria are e.g low heavy-metal content, no ecotoiddty, no obviously cbeguehabla residues.
3.3
composting
aerobic process designed to produce compost
3.4
disIntegration
physical eakdown of a material .ito very small fragments
3.5
dry mass
mass of a sample measured after drying
NOTE Dry mass is expressed sa a percentage of the mass of the wet sample.
3.6
m.sopl’iIlIc incubation p.riod
incubation at 25 C to allow the development 01 miaoorganisms growing at room temperature
3.7
thennophilic Incubation period
incubation at 56 C to allow the development of microorganisms growing at high temperature
3.8
total dry solids
amount of solids obtained by taking a known volume ci test material or compost and drying at about 105 C to constant mass
3.9
volatil, solids
amount of solids obtained by subtracting the residue obtained from a known volume of test material or compost alter Incineration at about 550 C from the total dry solids content of the same sample
NOTE Th voeatile-solids content Is an indlIon of the aniDunt or organic matter present
4 Pnnciple
The method determines the degree of disintegration of test materials on a laboratory scale under conditions swnulating an intensive aerobic composting process. The solid matrix used consists of a synthetic solid waste Inoculated with mature compost taken from a commercial composting plant, Pieces of the plastic test material are composted with this prepared solid matrix. The degree of disintegration is determined after a composting cycle, by sieving the final matrix through a 2mm sieve in order to recover the non.dlslntegrated residues The reduction in mass of the test sample is considered as disintegrated material and used to calculate the degree of disintegration.
5 Synthetic solid waste
The composition of the synthetic waste used Wi this method is described in Table 1.
Wel aerated compost from a commercial aerobic composllng plant shall be used as the inoculum. The compost inoculum shalt be homogeneous and free from large inert objects such as glass, stones or pieces of metal. Remove any such objects manually and then sieve the compost on a screen of mesh aperture between 0,5cm and 1 cm. It is recommended that compost from a plant composting the organic fraction of solid municipal waste be used In order to ensure sufficient diversity of microorganisms. It such a compost is not avadabte. then compost from plants treating farmyard waste or mixtures of garden waste and solid muniopal waste may be used The compost shed not be older than 4 months.
Prepare the synthetic waste manually by mixing the different components listed In Table 1. The allowed tolerance on the mass measurements of the synthetic waste components, water included, is 5 %. Add chlorine-free tap waler, or de-ionzed or distilled water, to the mixture to adjust Its final water content to 55 % in total. Perform this operation just before stall-up, The synthetic waste shall have a carbon:nitrogen (C/N) ratio of between 20:1 and 40:1 The urea concentration can be changed to adust the C/N ratio to the requwed range. In this case, the concentration of the other components shall be adjusted proportionately in order to bring the total dry mass of the solid waste to 100 %.
6 Composting reactor
The preferred composting reactor is a box made of poropytene or other suitable material, having the following dImensions: 30cm x 20cm x lOan (I, w, h). The box shall be covered with a lid assuring a tight seal to avoid excessive evaporation. Mditionally. any gap between box and lid may be sealed with adhesive tape. In the middle of the two 20cm wide sides, a hole of 5mm diameter Shall be made approxrately 6.5cm from the bottom of the box. These two holes provide gas exchange between the inner atmosphere and the outside envWonmenl and shall not be blocked.
Other containers wSh a vottane between 51 and 20 I may also be used, provided that it can be verifIed that no unfavourable anaerobic conditions are generated The container shall be closed in a way wtilch avoids excessive drying-out of the contents. Again, openings shall be provided in order to allow gas exchange and ensure aerobic conditions throughout the oomposting phase
7 Procedure
7.1 Test material preparation
Cut up lest material to give pieces with the dimensions defined In Table 2. based on the thickness of the material.
Ory the pieces at test material In an oven at (40 t 2 C under vacuum far the length of time needed to reach constant mass, Prior to mixing the pieces of test matertal with the stheUc waste, Immerse them in distilled water for no mare than 30 s.
7.2 Start-up of the test
Prepare a minimum of three reactors for each test material. Take between 59 and 20g of test material per reactor, depending on the volume occupied by the test material, and mix it with 1 kg of wet synthetic waste. The ratio of the mass of lest material to the mass of wet synthetic waste shal be In the range from 0.5 % to 2%. Place the mixture on the bottom of the reactor, forming a homogeneous layer. Do not compress the mixture, allowing efficient gas exchange with the Interior of the bed. Record the mass of test material in each reactor.
7.3 Thermophilic Incubation period (high temperature)
Close and weigh each reactor and place it In an air-circulation oven maintained at a constant temperature of (58±2) C for a minimum period of 45 days and a maximum of 90 days. Record the temperature of the oven throughout the test period or. altemallvely, use a maximLwn.mlnwnLmi thermometer, checking the temperature at least twice a week.
To ensure a good composting process, It is necessary to maintain suitable environmental conbons, Follow the procedure desaibed in Table 3. This procedure aerates the composting matter whilst maintaining a sufficient waler content. The gross mass of the reactor filled with the mixtiwe is determined at the beginning of the coniposting process. At each scheduled point in time (see Table 3), the reactor is weighed and. if needed. the initial mass restored totally or In part by adding chlorine-free lap waler, de.ionized water or distilled water as indicated in Table 3. It is i’nportarit to note that the optimum water concentration is obtained when the composling matter is wet but no free water is present. This means that the maximum waler-absorbing capacity has not been reached, The operator can determine this condition by squeezing the composting mallet, which shat exude a small amount of water. The operator can then ad$jst the amount of water to be added indicated in Table 3 on the basis of this direct ched.
xing of the composting matter cen be performed with a laboratory spatula or a common spoon. This operation shall be carried out carefully, paying attention not to damage the pieces of test material in the composting matter, The purpose of mixing Is to aerate the mass and remo the water, but it is important to avoid any mechanical degradation of the pieces of test material.
7.4 Mesophilic incubation period (at room temperature)
If at the end of the thermophilic incubation period the lest material has not sufficiently disintegrated. it is possille to extend the test, using the following pe’oce&re. Add 25g of fertile earth to each reactor. Mix the compost and the earth gently to avoid any mechanical damage to the residual pieces of test material Close each reactor and leave it In an air-circulation oven at (25±2)C for a maxmum period of 90 days. Record the temperature of the oven throughout the test period or, alternatively, use a maximum-minimum thermometer, checking the temperature at least twice a week Chedi the mass once a week and add water, if needed, to restore the mass to 70% of the mass measured at the beginning of the test (see 7.3), Do not mix the compoeting mass during this period.
It the test is extended In this way, this shal be mentioned in the test report
e) a table showing, tot each reactor. the following Information: the senal number of the reactor, the designation of the test material, the amount of synthetic waste introducad, the total amoialt of mixture (synthetic waste plus test material) and the Initial mass of the reactor (gross mass);
I) a table showing, for each reactor, the number of the reactor and the following characteristics of the compost, determined after sieving the total mass, the dry mass (expressed as a percentage of the 101st mass), the volatile-solids content (expressed as a percentage of the dry mass), the C1N ratio and the pH:
g) a table showing, for each mactot, the following Information: the number of the reactor and the decrease R in the total volatile-solids content, calculated as indicated in Clause 13, item a)
h) a table shoalng, for each reactor, details of the water-addition and mixing operations performed (day. operation performed, amount of water added, mass of reactor and any observations);
I) a table showing, for each reactor, the initial amount of test material, the amount of test material recovered at the end of the test and the degree of disintegration D, calculated as indicated In Clause 11;
j) information on the compost lnocdum used, such as source, age, date of colection, storage, handbng, stabihzalion, total dry mass, volatile-solids content, pH-value of a suspension (Ic. 1 part ci compost with 6 parts of deionized water), and specific odours and visual appearance of the compost, if any.