ISO INTERNATIONAL STANDARD 11794 Second edition 2017-06 Copper, lead, zinc and nickel concentrates Sampling of slurries Concentreés de cuivre, de plomb, de zinc et de nickel - Echantillonnage des schlamms Reference number IS0 11794:2017(E) International Organization for Standardization See=ZHEJIANG INST OF STANDARDIZATION C1 5956617 @ IS0 2017 vided by IHS under I Not for Resale, 2017/8/21 01:20:36 No reproduction or networking permitted without license from IHS IS0 11794:2017(E) COPYRIGHT PROTECTED DOCUMENT IS0 2017, Published in Switzerland All rights reserved. Unless otherwise specified, 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 Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 [email protected] www.iso.org Licensee-ZHEJIANG INST OF STANDARDIzRoISQ 7 - All rights reserved networking permited without license from IHS IS0 11794:2017(E) Contents Page Foreword ..V 1 Scope .1 2 Normative references ..1 3 Terms and definitions 4 Principles of sampling slurries ..2 4.1 General 2 4.2 Sampling errors. 4.2.1 General .3 4.2.2 Preparation error, PE .4 4.2.3 Delimitation and extraction errors, DE and EE 4 4.2.4 Weighting error, WE. ..6 4.2.5 Periodic quality-fluctuation error, QE3 ·6 4.3 Sampling and total variance .6 4.3.1 Sampling variance. .6 4.3.2 Total variance .6 4.3.3 Sampling-stage method of estimating sampling and total variance 4.3.4 Simplified method of estimating sampling and total variance. .9 4.3.5 Interleaved sample method of measuring total variance ..10 5 Establishing a sampling scheme ..11 6 Minimization of bias and unbiased increment mass. ..16 6.1 Minimization of bias. ..16 6.2 Volume of increment for falling-stream samplers to avoid bias. ..17 7 Number of increments ..17 7.1 General ..17 7.2 Simplified method. ..18 8 Minimum mass of solids contained in lot and sub-lot samples. ...18 8.1 Minimum mass of solids in lot samples. ..18 8.2 Minimum mass of solids in sub-lot samples. .18 8.3 Minimum mass of solids in lot and sub-lot samples after size reduction ..18 6 Time-basis sampling ..19 9.1 General. 19 9.2 Sampling interval. ..19 9.3 Cutters ..19 9.4 Taking of increments .19 9.5 Constitution of lot or sub-lot samples .19 9.6 Division of increments and sub-lot samples 20 9.7 Division of lot samples 20 9.8 Number of cuts for division .20 10 Stratified random sampling within fixed time intervals ..20 11 Mechanical sampling from moving streams .21 11.1 General 21 11.2 Design of the sampling system. 21 11.2.1 Safety of operators 21 11.2.2 Location of sample cutters. 21 11.2.3 Provision for duplicate sampling 21 11.2.4 System for checking the precision and bias 21 11.2.5 Avoiding bias. 21 11.3 Slurry sample cutters .22 11.3.1 General 22 11.3.2 Falling-stream cutters. .22 ntemaionalganzation7All rights reserved ii Censee=ZHEJIANG INST OF STANDARDIZATION C1 5956617 e with ISt ed without license from IHS Not for Resale, 2017/8/21 01:20:36 No reproduction or networking pe