What is ISO 20049-1- Self-heating of pelletized biofuels by Isothermal calorimetry about?
ISO 20049-1:
- Specifies a general test procedure for quantification of the spontaneous heat generation from solid biofuel pellets using isothermal calorimetry
- Specifies a screening test procedure for wood pellets using an instrument temperature of 60 °C;
- Establishes procedures for sampling and sample handling of solid biofuel pellets prior to the analysis of spontaneous heat generation
- Gives guidance on the applicability and use of isothermal calorimetry for calculation of the net reaction rate of the heat producing reactions of solid biofuel pellets
The test procedure given in ISO 20049-1 quantifies the thermal power (heat flow) of the sample during the test. The results are product specific. ISO 20049-1 is applicable to solid biofuel pellets only.
Who is ISO 20049-1-Self-heating of pelletized biofuels by Isothermal calorimetry for?
ISO 20049-1 on isothermal calorimetry is beneficial for:
- Manufacturers and producers of biofuel pellets
- Consultants and authorities
- Pharmaceuticals, energetic materials, and cement industries
- Manufacturers and producers of wood pellets
Why should you use ISO 20049-1-Self-heating of pelletized biofuels by Isothermal calorimetry?
There is a continuous global growth in production, storage, handling, bulk transport and use of solid biofuels especially in the form of pelletized biofuels. Solid biofuels such as wood pellets, however, are intrinsically sterile due to the conditions during manufacturing (exposure to severe heat during drying, fragmentation during hammermilling and pressure during extrusion) but can attract microbes if becoming wet during handling and storage resulting in metabolism and generation of heat.
The potential for self-heating seems to vary considerably for different types of solid biofuel pellets. The raw material used, and the properties of these raw materials have proven to influence the propensity for self-heating of the produced wood pellets. However, the production process (e.g., the drying process) also influences the potential for self-heating. It is therefore important to be able to identify solid biofuel pellets with high heat generation potential to avoid fires in stored materials.
Two intrinsically different types of tests methods can be used to estimate the potential of self-heating:
- In the isothermal calorimetry method described in ISO 20049-1, the heat flow generated from the test portion is measured directly
- In basket heating tests, the temperature of the test portion is being monitored and the critical ambient temperature (CAT), where the temperature of the test portion just does not increase significantly due to self-heating, is used for indirect assessment of self-heating
These two methods are applied at different analysis temperature regimes. The operating temperature for an isothermal calorimeter is normally in the range 5 °C to 90 °C whereas basket heating tests are conducted at higher analysis (oven) temperatures. For basket heating tests with wood pellets, CATs are found for a 1 l sample portion in the range 150 °C to 200 °C.
Overall, ISO 20049-1 is helpful because describes about isothermal calorimetry and isothermal calorimetry is used for determination of the thermal activity or heat flow of chemical, physical and biological processes. The method described in ISO 20049-1 is developed for the measurement of heat flow from the self-heating of solid biofuel pellets, but the technique is most commonly used in the fields of pharmaceuticals, energetic materials, and cement.
