ISO/TC 238/WG 7 - Safety of solid biofuels

This document specifies basket heating tests for the characterization of self-heating properties of solid biofuel pellets. This document includes: a) a compilation of basket heating test methods; b) guidance on the applicability and use of basket heating tests for solid biofuel pellets; c) information on the application of basket heating test data for calculations of critical conditions in storages. Data on spontaneous heat generation determined using this document is only associated with the specific quality and age of the sample material. The information derived using this document is for use in quality control and in hazard and risk assessments related to the procedures given in ISO 20024. The described methods can be used for other substances than solid biofuel pellets (e.g. wood chips).

This document: a) specifies a general test procedure for quantification of the spontaneous heat generation from solid biofuel pellets using isothermal calorimetry; b) specifies a screening test procedure for wood pellets using an instrument temperature of 60 °C; c) establishes procedures for sampling and sample handling of solid biofuel pellets prior to the analysis of spontaneous heat generation; and d) 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 this document quantifies the thermal power (heat flow) of the sample during the test, it does not identify the source of self-heating in the test portion analysed. Data on spontaneous heat generation determined using this document is only associated with the specific quality and age of the sample material. The results are product specific. This document is applicable to solid biofuel pellets only. The information derived using this document is for use in quality control and in hazard and risk assessments related to the procedures given in ISO 20024:2020.

This document defines a method for determination of off-gassing (permanent gases) and oxygen depletion from woody as well as non-woody biomass, including densified materials such as pellets and briquettes, as well as non-densified materials such as chips. The method is also applicable for thermally treated materials, including torrefied and carbonized materials. The emission and depletion factor and emission and depletion rate for various gas species emitted from sample within a closed test container is determined by means of gas chromatography. The emission and depletion factor and emission and depletion rate provide guidance for ventilation requirements to keep gas concentrations below Permissible Exposure Levels (PEL) in spaces where workers can be exposed to the enclosed atmosphere.

This document provides principles and requirements for safe handling and storage of solid biofuels pellets in commercial and industrial applications. This document is using a risk-based approach to determine what safety measures should be considered. Facilities with a storage capacity This document covers the handling and storage process of pellets in the following applications: — at a pellet production plant from the outlet of the cooler unit until loaded for transportation; — at a commercial distributor from the receiving station until loaded for transportation; and — at an industrial end-user from the receiving station until fed into the fuel preparation or combustion process. Although unloading and loading of e.g. vessels, trains or trucks are included in the operational envelops defined above, the safety aspect of the transportation itself is beyond the scope of this document. This document also gives specific guidance on detection and suppression systems and preparatory measures to enable safe and efficient firefighting operations. Guidance on the management of fire and explosion incidents is also specified.

This document provides principles and requirements for the safe handling and storage of wood pellets in residential and other small-scale applications. It covers the supply chain from loading of the delivery truck, requirements of delivery trucks, connections to the end-user's store and the delivery process. It also covers the design and construction of pellet storage systems. This document addresses risks of fires, dust explosions, off-gassing, oxygen depletion, damage to appliances and buildings through swelling of pellets and other health risks. It is applicable to wood pellets according to ISO 17225-2.