EN ISO 18125:2017

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents
6 Apparatus
7 Preparation of test sample
8 Calorimetric procedure
9 Calibration
10 Gross calorific value
11 Performance characteristics
12 Calculation of net calorific value at constant pressure
13 Test report
Annex A (normative) - Adiabatic bomb calorimeters
Annex B (normative) - Isoperibol and static-jacket
        bomb calorimeters
Annex C (normative) - Automated bomb calorimeters
Annex D (informative) - Checklists for the design and
        procedures of combustion experiments
Annex E (informative) - Examples to illustrate the main
        calculations used in this document when an automated
        bomb calorimeter is used for determinations
Annex F (informative) - List of symbols used in this
        document
Annex G (informative) - Default values of most used solid
        biofuels for the calculations of calorific values
Annex H (informative) - Flow chart for a routine calorific
        value determination
Bibliography
Index

ISO 18125:2017 specifies a method for the determination of the gross calorific value of a solid biofuel at constant volume and at the reference temperature 25 °C in a bomb calorimeter calibrated by combustion of certified benzoic acid.The result obtained is the gross calorific value of the analysis sample at constant volume with all the water of the combustion products as liquid water. In practice, biofuels are burned at constant (atmospheric) pressure and the water is either not condensed (removed as vapour with the flue gases) or condensed. Under both conditions, the operative heat of combustion to be used is the net calorific value of the fuel at constant pressure. The net calorific value at constant volume may also be used; formulae are given for calculating both values.General principles and procedures for the calibrations and the biofuel experiments are presented in the main text, whereas those pertaining to the use of a particular type of calorimetric instrument are described in Annexes A to C. Annex D contains checklists for performing calibration and fuel experiments using specified types of calorimeters. Annex E gives examples to illustrate some of the calculations.