Determination of calorific value of coal

This standard corresponds to ISO 1928: 1995 "Solid Fossil Oxygen Bomb Calorimetry Determination of High-Level Calorific Value and Calculation of Low-Level Calorific Value" (English version). The consistency of this standard with ISO 1928: 1995 is not equivalent, and the main differences are as follows:
— Increased requirements for laboratories;
— Use the inference algorithm instead of the actual measurement method to calculate the temperature change rate of the inner cylinder;
— The empirical formula in the cooling correction formula replaces the American formula with the Chinese formula (Dickinson extrapolation method);
— Added specific nitric acid correction thermal experience calculation formula;
— Decompose a high-level calorific value calculation formula into two calculation formulas of cartridge calorific value and high-level calorific value;
— Deleted unnecessary chapters and appendices, and moved the substantive content to other relevant chapters.
This standard replaces GB / T 213-1996 "Determination of calorific value of coal".
This standard is compared with GB / T 213-1996. The main changes are as follows:
— Added the definition and calculation example of constant pressure low-level calorific value (3.5 and Appendix B.6 in this edition);
— The repeatability of the thermal capacity calibration is changed from the extreme 40J / K to the relative standard deviation. .20% (10.8 in the 1996 edition and 10.8 in this edition);
— Delete Chapter 11, “About Automatic Calorimeters”, move the content to the “calorimeter” clause, and add more detailed provisions (11 in 1996, 7.1.1 in this edition)
— The reproducibility limit in the precision of the method was changed from 150 J / g to 120 J / g (13 in 1996, 12 in this edition);
— Correction item for adding nitrogen in the calculation formula of constant pressure low calorific value (14.2 in 1996 edition and 13.2 in this edition);
— Added the conversion formula for the calorific value of different bases (this version 14. 2);
— Added requirements for test reports (this edition 15);
— Add description of the method of calculating relative standard deviation (Appendix A of this edition);
— Add a method to determine the sulfur in the cartridge washing liquid (Appendix C of this edition);
Appendix A of this standard is a normative appendix, and Appendix B and Appendix C are informative appendices.
This standard was proposed by China Coal Industry Association.
This standard is under the jurisdiction of the National Coal Standardization Technical Committee.
This standard was drafted by: Coal Analysis Laboratory, General Coal Research Institute.
The main drafters of this standard: Li Yinghua, Pi Zhongyuan.
The previous versions and releases replaced by this standard are:
GB 213-63, GB 213-74, GB 213-79, GB 213-87, GB / T 213-1996

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