ISO INTERNATIONAL STANDARD 7992 Fourth edition 2022-05 Iron ores for blast furnace feedstocks Determination of reduction under load Minerais de fer pour charges de hauts fourneaux - Détermination de la réduction sous charge Reference number IS0 7992:2022(E) ISO @ IS0 2022 IS0 7992:2022(E) COPYRIGHT PROTECTED DOCUMENT @IS02022 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below or ISo's member body in the country of the requester. ISO copyright office CP 40i : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone: +41 22 749 01 11 Email: [email protected] Website: www.iso.org Published in Switzerland ii IS02022-Allrightsreserved IS0 7992:2022(E) Contents Page Foreword. ..iv Introduction. .. 1 Scope. ..1 2 Normative references ..1 3 Terms and definitions 4 Principle. ..1 5 Sampling, sample preparation and preparation of test portions .2 5.1 Sampling and sample preparation .2 5.2 Preparation of test portions.. ..2 6 .2 Apparatus 7 Test conditions .6 7.1 General .6 7.2 Reducing gas .6 7.2.1 .6 Composition 7.2.2 Purity. .6 7.2.3 Flow rate 6 .7 7.3 Heating and cooling gas 7.4 Temperature of the test portion 7 7.5 Loading of the test portion. 7 .7 8 Procedure 8.1 Number of determinations for the test 7 8.2 Chemical analysis. .7 Reduction .1 8.3 Expression of results ..8 9 9.1 Preparation of the reduction curve ..8 9.2 Calculation of the differential pressure at 80 % reduction (p80) .8 9.3 Calculation of the change in the height of the test bed at 80 % reduction (Ah80) ..8 9.4 Repeatability and acceptance of test results. .9 10 ..9 Test report ..9 11 Verification Annex A (normative) Flowsheet of the procedure for the acceptance of test results ..11 ..12 Annex B (informative) Derivation of equation for reducibility iii IS02022-Allrightsreserved