BS ISO 13317-1-2001 Determination of particle size distribution by gravitational liquid sedimentation methods - General principles and guidelines《用重力液体沉淀法测定粒度分布 通用原则和指南》.pdf

1、BRITISH STANDARD BS ISO 13317-1:2001 Determination of particle size distribution by gravitational liquid sedimentation methods Part 1: General principles and guidelines ICS 19.120 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBS ISO 13317-1:2001 This British Standard, having

2、been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 July 2001 BSI 07-2001 ISBN 0 580 37510 2 National foreword This British Standard reproduces verbatim ISO 13317-1:2001 and im

3、plements it as the UK national standard. Together with BS ISO 13317-2:2001 and BS ISO 13317-3:2001 it supersedes BS 3406-2:1984, which is withdrawn. The UK participation in its preparation was entrusted by Technical Committee LBI/37, Sieves, screens and particle sizing, to Subcommittee LBI/37/4, Par

4、ticle sizing by methods other than sieving, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be fou

5、nd in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standard

6、s are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for chang

7、e, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 17 and a back cover. The BSI copyri

8、ght date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsReference number ISO 13317-1:2001(E) INTERNATIONAL STANDARD ISO 13317-1 First edition 2001-05-01 Determination of particle size distribution by gravitational liq

9、uid sedimentation methods Part 1: General principles and guidelines Dtermination de la distribution granulomtrique par les mthodes de sdimentation par gravit dans un liquide Partie 1: Principes gnraux et lignes directricesISO 13317-1:2001(E) ii ISO 13317-1:2001(E)iii Contents Page Foreword.iv Introd

10、uction.v 1 Scope 1 2 Normative references 1 3 Terms, definitions and symbols.2 4 Principles4 5 Particle size, shape and porosity limitations5 6 Test conditions 7 7 Sampling.8 8 Preparation for a sedimentation analysis .8 9 Tests in duplicate and validation .9 10 Reporting of results.10 Annex A (info

11、rmative) The effect of measurement zone height .11 Annex B (informative) Accuracy of Stokes law as a function of Reynolds number 13 Annex C (informative) Particle displacement due to Brownian motion.14 Annex D (informative) Effect of open pores on the terminal velocity of spherical particles.15 Bibl

12、iography17ISO 13317-1:2001(E) iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body inte

13、rested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnica

14、l Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publicati

15、on as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this part of ISO 13317 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such pat

16、ent rights. International Standard ISO 13317-1 was prepared by Technical Committee ISO/TC 24, Sieves, sieving and other sizing methods, Subcommittee SC 4, Sizing by methods other than sieving. ISO 13317 consists of the following parts, under the general title Determination of particle size distribut

17、ion by gravitational liquid sedimentation methods: Part 1: General principles and guidelines Part 2: Fixed pipette method Part 3: X-ray gravitational technique Annexes A to D of this part of ISO 13317 are for information only.ISO 13317-1:2001(E)v Introduction Gravitational sedimentation particle siz

18、e analysis methods are among those in current use for determining size distribution of many powders. Typically, the gravitational methods apply to samples in the 0,5 mt o1 0 0 ms i z e range and where the sedimentation condition for a Reynolds number 0,25 is satisfied. No single method of size analy

19、sis can be specified to cover the many different types of material encountered, but it is possible to recommend procedures that may be applied in the majority of cases. The purpose of this part of ISO 13317 is to obtain uniformity in procedure for any gravitational method selected to facilitate comp

20、arisons of size analysis made in different laboratories. Gravitational sedimentation methods may be undertaken: as part of a research project involving an investigation of the particle size distribution of a material; as part of a control procedure for the production of a material where the particle

21、 size distribution is important; as the basis of a contract for the supply of material specified to be within stated specification limits.INTERNATIONAL STANDARD ISO 13317-1:2001(E)1 Determination of particle size distribution by gravitational liquid sedimentation methods Part 1: General principles a

22、nd guidelines 1 Scope This part of ISO 13317 covers methods for determining the particle size distributions of particulate materials, typically in the size range 0,5 m to 100 m, by gravitational sedimentation in a liquid. NOTE This part of ISO 13317 may involve hazardous materials, operations and eq

23、uipment. This part of ISO 13317 does not purport to address all the safety problems associated with its use. It is the responsibility of the user of this part of ISO 13317 to establish appropriate safety and health practices and to determine the applicability of the regulatory limitations prior to i

24、ts use. The methods of determining the particle size distribution described in this part of ISO 13317 are applicable to slurries or to particulate materials which can be dispersed in liquids. A positive density difference between the discrete and continuous phases is necessary, although gravitationa

25、l photosedimentation can be used for emulsions where the droplets are less dense than the liquid in which they are dispersed. Particles should not undergo any physical or chemical change in the suspending liquid. The usual precautions need to be taken with hazardous material, and explosion proof ana

26、lysers are required when examining volatile liquids with a low flash point. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of ISO 13317. For dated references, subsequent amendments to, or revisions

27、 of, any of these publications do not apply. However, parties to agreements based on this part of ISO 13317 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative docum

28、ent referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 758, Liquid chemical products for industrial use Determination of density at 20 C. ISO 787-10, General methods of test for pigments and extenders Part 10: Determination of density Pykno

29、meter method. ISO 2591-1, Test sieving Part 1: Methods using test sieves of woven wire cloth and perforated metal plate. ISO 8213, Chemical products for industrial use Sampling techniques Solid chemical products in the form of particles varying from powders to coarse lumps. ISO 9276-1, Representatio

30、n of results of particle size analysis Part 1: Graphical representation. ISO 13317-2, Determination of particle size distribution by gravitational liquid sedimentation methods Part 2: Fixed pipette method. ISO 13317-3, Determination of particle size distribution by gravitational liquid sedimentation

31、 methods Part 3: X-ray gravitational technique. ISO 14887, Sample preparation Dispersing procedures for powders in liquids.ISO 13317-1:2001(E) 2 3 Terms, definitions and symbols 3.1 Terms and definitions For the purposes of this part of ISO 13317, the following terms and definitions apply. 3.1.1 ter

32、minal settling velocity velocity of a particle through a still liquid at which the force due to gravity on the particle is balanced by the drag exerted by the liquid 3.1.2 Stokes diameter equivalent spherical diameter of the particle that has the same density and terminal settling velocity as the re

33、al particle in the same liquid under creeping flow conditions 3.1.3 open pores cavities that are connected to the external surface of the particle either directly or via one another 3.1.4 closed pores cavities that are closed off by surrounding solid and are inaccessible to the external surface 3.1.

34、5 oversize portion of the charge which has not passed through the apertures of a stated sieve 3.1.6 undersize portion of the charge which has passed through the apertures of a stated sieve 3.1.7 effective particle density particle mass divided by the volume of liquid it displaces 3.1.8 true particle

35、 density particle mass divided by the volume it would occupy excluding all pores, closed or open, and surface fissures NOTE True particle density is sometimes referred to as the absolute particle density.ISO 13317-1:2001(E)3 3.2 Symbols For the purposes of this part of ISO 13317, the following symbo

36、ls apply. Quantity Symbol Unit Derivative unit Effective particle density s kg m 3 g cm 3 Liquid density l kg m 3 g cm 3 True particle density (no porosity) p kg m 3 g cm 3 Liquid viscosity Pasm P a s Acceleration due to gravity g m s 2 Sedimentation distance h mm m Sedimentation time t s Stokes dia

37、meter x St m m Upper Stokes diameter x St,U m m Lower Stokes diameter x St,L m m Particle diameter exiting measurement zone x St,h m m Particle diameter entering measurement zone x St,h h m m Terminal settling velocity v m s 1 m s 1 Reynolds number Re dimensionless Grouped parameter K 1 m s Grouped

38、parameter K 2 m 3 s 1 Hyperbolic scan constant K scan m s Boltzmann constant k J K 1 Absolute temperature (Kelvin) T K Particle porosity dimensionless Fraction of open particle porosity filled with sedimentation liquid f dimensionless Fractional uncertainty of particle position due to thermal diffus

39、ion f diff dimensionless Statistical average positional change in one direction for large number of particles due to thermal diffusion h diff m m Thickness of measurement zone h zone m m Resolution ratio P dimensionless Minimum acceptable resolution P min dimensionless Zone-height-limited resolution

40、 P zone dimensionless Minimum settling distance for acceptable resolution, P min h zone,Pmin m mISO 13317-1:2001(E) 4 4P r i n c i p l e s 4.1 General Gravitational sedimentation methods are based on the settling velocity, under a gravitational field, of particles in a liquid. The relationship betwe

41、en settling velocity and particle size reduces to the Stokes equation (1) at low Reynolds numbers. The Reynolds number should not exceed 0,25 if the inaccuracy in determining the value of Stokes diameter is not to exceed 3 %. Stokesian sedimentation analyses depend on the applicability of Stokes law

42、. This law defines the relationship between particle size and the change in height (within the suspending fluid) of the particle as a function of the time that the particle has fallen after reaching its terminal velocity. 2 s1S t fall ( ) = 18 gx t h (1) Note that h fall is defined so that it increa

43、ses as the particle falls to lower positions in the sedimentation vessel. This equation may be expressed such that the Stokesian diameter of the particle may be inferred from the distance it has fallen in a given time, t. fall St s1 18 = ( ) h x gt (2) Sedimentation techniques may be classified as e

44、ither incremental or cumulative. Incremental methods are used to determine the solids concentration (or suspension density) of a thin layer at a known height and time. Cumulative methods are used to determine the rate at which solids settle from the suspension. In both methods, the powder may be int

45、roduced either as a thin layer on top of a column of liquid (the line-start technique), or uniformly dispersed at the start of the analysis (the homogeneous technique). The cumulative method is not part of this part of ISO 13317. The incremental homogeneous technique is more often used in gravitatio

46、nal sedimentation (Figure 1) and is described in this part of ISO 13317. The line-start technique is more applicable to centrifugal sedimentation and is part of ISO 13318-2. 4.2 Calculation of particle size Stokes diameters are calculated according to equation (2). 4.3 Calculation of cumulative mass

47、 percentage The cumulative mass percentage according to the particle concentration gradient in the gravitational pipette method and in the gravitational X-ray method shall be determined according to ISO 13317-2 and ISO 13317-3 respectively. 4.4 Effect of measurement zone height on resolution Informa

48、tion on the effect of measurement zone height on resolution is given in annex A.ISO 13317-1:2001(E)5 Key t Time 1 Settling height 2 Measurement zone Figure 1 Homogeneous, incremental, gravitational sedimentation 5 Particle size, shape and porosity limitations 5.1 Upper size limit Stokes equation pre

49、dicts that the terminal settling velocity that a particle will reach in a gravitational field is 2 St 1 = x v K (3) where 1 s1 18 = ( ) K g (4) is expressed to solve the Stokesian diameter of the particle St 1 = xK v (5) Since the terminal settling velocity is constant and attained quickly, h fall = v t fall , the particle diameter can be estimated from the distance the particle falls during a given time: 1f a l l St f