ISO TS 20048-1-2020 pdf download.Solid biofuels – Determination of off-gassing and oxygen depletion characteristics一 Part 1: Laboratory method for the determination of off-gassing and oxygen depletion using closed containers.
7.2 Filling of test containers
Mark the test container at the 75 % level.
Fill each container to the 85 % level with the biomass test material to be tested. In order to achieve a representative packing density, expose the test container to shock by means of dropping the container 5 times from a height of 50 mm onto a wooden board on an even horizontal and hard workbench or floor. Make sure the test container hits the wooden board in a vertical position and that the level of test material reaches the 75 % level. Refill or remove material if necessary, to reach the 75 % level. This procedure shall be repeated until the packing density is stable.
If more than one test container is used, mark the containers with different letters A, B,C etc., and weigh the content of each container to make sure each container has the same weight within I % of weight.
If there is dust remaining on the rim of the test container, swipe it off with a cloth.
Apply the lid assembly with the sampling port to the test container and seal it. Tighten all connections.
To make it air-tight. use an extra sealant, such as silicone, around the fittings on the side of the lid that
Is exposed to air when the container Is closed, No extra sealant shall be used on the inner side of the lid.
Ensure that the sealant chosen can be used in the temperatures it will be exposed to during the test.
The container called PEAK is sampled only once when the sampling is completed. It is to verify the peak emission value at the end of the test period
7.3 Test container arrangement and test gas sampling volume
The different gas species evolve at different rates, which mean that the relative ratio of gases can change slightly over time as the oxygen is consumed. Also, the temperature can affect the relative rate of evolution of the various gas species. The oxygen content in the containment is depleted as a function of oxidation of components of the biomass. In order to obtain a representative profile of emissions for long term storage, emission and depletion factors and emission and depletion rates for gas species shall be defined over an extended period of time such as 28 to 30 days. Due to this relatively long period of time, considerations shall be given to testing more than one biornass test material at a time. For example, reference material and several test samples can be processed in parallel. If testing is done at various temperatures such as 20 °C/30 °C/40 °C/50 °C there shall be one oven per temperature.
NOTE Using more than one oven per temperature is not recommended since there will be some difference in the temperature which could affect the results.
Consideration shall be given to maximum allowable gas depletion due to sampling and the number of days samples should be taken.
Figure 3 illustrates arrangements of four test containers in an oven.ISO TS 20048-1 pdf download.