1)Verifying the biodegradation behavior under anaerobic digestion conditions,52度(2) Verifying the biodegradation behavior under (accelerated) landfill conditions,37度
ASTM D.5511 can also be used to evaluate landfill. And has indeed a double purpose in that sense.
ISO 15985 is basically identical.
1. Biodegradation test
References
· ISO 15985
· ASTM D5511
Principle
This method consists in a high-rate dry anaerobic batch fermentation, determining the inherent biodegradability of a substance in a sanitary landfill or in a solid state anaerobic digestion system. This method simulates and accelerates the biodegradation process that takes place in a landfill because it is a stationary (no mixing) and dry (35% to 40% solids) fermentation under optimal conditions.
A small amount of test item is added to a large amount of highly active inoculum that has been stabilized prior to the start of the digestion period. Optimal conditions are provided and the mixture is left to ferment batch wise. The volume of the biogas produced is then measured and the amount of CH4 and CO2 produced per weight unit of test item is calculated. If the carbon content of the test substance is known, the percentage of biodegradation can be calculated as the percentage of solid carbon of the test item which has been converted to gaseous, mineral C. Other, secondary, parameters can be observed, such as weight loss and particularly the disintegration of the test substance (see also Chapter 2).
This test method can be executed at thermophilic (52°C) or at mesophilic (37°C) temperatures.
Sample
At least 100 g is required. The sample(s) is (are) preferably being tested as powder, but can be provided as pellets (in case of plastic) or sheets (in case of paper and other natural materials) as well. In the latter case, cryogenic milling is required (extra cost, see below). Eventually, the plastic sample(s) can also be provided under the form of film, yet, milling will take (much) longer and hence milling cost will be (much) higher.
Price
The price for 1 sample under certification, respectively screening conditions is given in the table below. The difference between certification and screening conditions is explained on the last page of the proposal. In case more than 1 sample is to be analyzed at the same time, a discount of 20% per sample can be given. For 5 or more samples in parallel a discount of 30% per sample is offered.