BS ISO 1170:2020 pdf download.Coal and coke — Calculation of analyses to different bases.
4 Principle
In order to convert an analytical result expressed on one basis to another basis, it is multiplied by a factor
calculated from the appropriate formulae (see Tab11) after insertion of the requisite numerical values.
5 Calculations for coal analyses
5.1 General
In International Standards covering the analysis of coal, it is generally specified that the determination shall be carried out on an air-dried test sample. However, in making use of these analyses, it is sometimes necessary to express or report the results on some other basis. The bases in common use are air-dried, as-received, “dry, dry, ash-free”, and “dry, mineral-matter-free.
5.2 Procedure
Any analytical value (except net calorific value) on a particular basis may be converted to any other basis by multiplying it by the appropriate factor calculated from the formulae given in Table 1, after insertion of the requisite numerical values for the symbols (for determination of moisture, see ISO 589, ISO 5068-1, ISO 5068-2 or ISO 11722 (as appropriate); for ash, see ISO 1171).
However, in some determinations, there is a direct involvement of the mineral matter and, in these cases, it is essential to apply a correction to the air-dried result prior to its calculation to the dry, mineral-matter-free basis. This correction is dependent on the nature, as well as the quantity, of the mineral matter present. The mineral matter is determined using ISO 602. If it is not possible or not desired to determine the mineral matter for any given sample, the formula recommended by the national standards organization of the country of origin of the sample should he used and should he quoted in full, together with the analysis. An example for a formula and further explanations are given in Annex A. All the determinations that may be expressed on the dry, mineral-matter-free basis are considered individually below.
If it is necessary to calculate an analytical result expressed on the dry, mineral-matter-free basis back to any other basis, then it is essential that any correction deducted during the application of any Formulae (1) to LWJ inclusive be added hack to the dry, mineral-matter-free value before applying the appropriate formula from Table 1.
5.10? Net? calorific? value The calculation of the net calorific value is dealt with in detail in ISO 1928, which, however, does not include calculation to a dry, mineral-matter-free basis as this basis is not of importance for net calorific values. NOTE Net calorific values cannot be converted to any other basis by direct multiplying with the appropriate formulas in Table 1 as net calorific values includes a correction for the heat of vaporization related to the actual moisture.
6 Calculations for coke analyses Coke analyses may be expressed on the “air-dried”, “as-received”, “dry” and “dry, ash-free” bases, and these values (except for net calorific value) are calculated by the use of the appropriate formulae given in Table 1, after insertion of requisite numerical values for the symbols (for determination of moisture, see ISO 579 and ISO 687; for ash, see ISO 1171). It is not proposed at present to recommend the calculation for the conversion of analytical results for coke to a dry, mineral-matter-free basis.BS ISO 1170 pdf download.