1、February 2011 Translation by DIN-Sprachendienst.English price group 10No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).I
2、CS 65.080!$mr.“1747911www.din.deDDIN EN 12948Liming materials Determination of size distribution by dry and wet sievingEnglish translation of DIN EN 12948:2011-02Calcium-/Magnesium-Bodenverbesserungsmittel Bestimmung der Korngrenverteilung durch Trocken- und NasssiebungEnglische bersetzung von DIN E
3、N 12948:2011-02Amendements minraux basiques Dtermination de la distribution granulomtrique par tamisage par voie sche ou par voiehumideTraduction anglaise de DIN EN 12948:2011-02SupersedesDIN EN 12948:2003-01www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be
4、considered authoritative.1502.11 DIN EN 12948:2011-02 2 A comma is used as the decimal marker. National foreword This standard has been prepared by Technical Committee CEN/TC 260 “Fertilizers and liming materials” (Secretariat: DIN, Germany). The responsible German body involved in its preparation w
5、as the Normenausschuss Lebensmittel und landwirtschaftliche Produkte (Food and Agricultural Products Standards Committee), Working Committee NA 057-03-02 AA Dngemittel. For terms related to sieve analysis, see DIN ISO 2395. The DIN Standards corresponding to the International Standards referred to i
6、n this document are as follows: ISO 565 DIN ISO 565 ISO 3310-1 DIN ISO 3310-1 ISO 3310-2 DIN ISO 3310-2 ISO 5725 DIN ISO 5725 Amendments This standard differs from DIN EN 12948:2003-01 as follows: a) the sampling method is not part of the standard. Informative reference to EN 1482-1 has been added;
7、b) a normative reference to EN 1482-2 concerning sample preparation has been added; c) a clarification of the method of dispersion of agglomerates in method B has been added; d) the Bibliography has been revised; e) the standard has been brought in line with the current rules of presentation; f) the
8、 German version of the standard has been editorially revised. Previous editions DIN EN 12948: 2003-01 DIN EN 12948:2011-02 3 National Annex NA (informative) Bibliography DIN ISO 565, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings DIN ISO 2395,
9、Test sieves and test sieving Vocabulary DIN ISO 3310-1, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth DIN ISO 3310-2, Test sieves Technical requirements and testing Part 2: Test sieves of perforated plates DIN ISO 5725 (all parts), Accuracy (trueness and prec
10、ision) of measurement methods and results DIN EN 12948:2011-02 4 This page is intentionally blank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12948 November 2010 ICS 65.080 Supersedes EN 12948:2002English Version Liming materials - Determination of size distribution by dry and wet sieving A
11、mendements minraux basiques - Dtermination de la distribution granulomtrique par tamisage par voie sche ou par voie humide Calcium-/Magnesium-Bodenverbesserungsmittel - Bestimmung der Korngrenverteilung durch Trocken- und Nasssiebung This European Standard was approved by CEN on 2 October 2010. CEN
12、members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on appli
13、cation to the CEN Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre h
14、as the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
15、Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and
16、by any means reserved worldwide for CEN national Members. Ref. No. EN 12948:2010: EEN 12948:2010 (E) 2 Contents Page Foreword 3Introduction .41 Scope 52 Normative references 53 Principle 54 Apparatus .55 Sampling and sample preparation .66 Procedure .67 Expression of results 88 Precision .99 Test re
17、port 9Annex A (informative) Results of an inter-laboratory trial to determine the size distribution by dry and wet sieving. 10Bibliography . 11DIN EN 12948:2011-02 EN 12948:2010 (E) 3 Foreword This document (EN 12948:2010) has been prepared by Technical Committee CEN/TC 260 “Fertilizers and liming m
18、aterials”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2011, and conflicting national standards shall be withdrawn at the latest by May 2011. Atten
19、tion is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 12948:2002. The following has been added to the former edition
20、of the European Standard: a) the sampling method is not part of the standard. Informative reference to EN 1482-1 added; b) normative reference to EN 1482-2 concerning sample preparation added; c) clarification of the method of dispersion of agglomerates in method B added; d) Bibliography revised. Ac
21、cording to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
22、Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. DIN EN 12948:2011-02 EN 12948:2010 (E) 4 Introduction The dry sieving of powdered material containing individual particles can be carried ou
23、t quite easily. This method is simple, quick, cheap and enables the determination of the particle size of water-soluble materials. Therefore the dry sieving method should always be used first. However, the sieve apertures can become blocked by sample particles, a phenomenon known as blinding. Blindi
24、ng is mainly caused by caking and the production of electrostatic charges, particularly on sieves with small apertures. Dry sieving of very wet material can also lead to blinding. These difficulties are not encountered with the wet sieving method, which is applicable to any kind of material such as
25、powders (dry or wet), paste-like products or granules except those containing water-soluble constituents. In order to ensure the comparability of results, all masses of size fractions are expressed as dry matter. The approach to methods and principles of sieving refers to existing guidelines and Eur
26、opean Regulations (1 and 2). DIN EN 12948:2011-02 EN 12948:2010 (E) 5 1 Scope This European Standard specifies two methods for the determination of the particle size distribution of liming materials. The dry sieving method (method A) is applicable to all liming materials except wet and paste-like pr
27、oducts. Method A is not applicable, if blinding, caking, electrostatic charges or agglomeration occur after pre drying. The wet sieving method (method B) is applicable to products which are susceptible to blinding, caking, electrostatic charges or agglomeration after pre drying. Method B can be used
28、 to determine the primary particle size distribution of granulated products. Method B is not applicable to burnt lime and liming materials containing water-soluble constituents. 2 Normative references The following referenced documents are indispensable for the application of this document. For date
29、d references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 1235:1995, Solid fertilizers Test sieving (ISO 8397:1988 modified) EN 1482-2, Fertilizers and liming materials Sampling and sample preparation Pa
30、rt 2: Sample preparation EN 12048, Solid fertilizers and liming materials Determination of moisture content Gravimetric method by drying at (105 2) C (ISO 8190:1992 modified) ISO 565, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings ISO 3310-1, T
31、est sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth 3 Principle 3.1 Method A Dry sieving of a liming material with one or more test sieves by hand or using a mechanical sieving machine. 3.2 Method B Wet sieving of a liming material, if necessary after dispersion und
32、er continuous water spraying, by hand or using a mechanical sieving machine. Drying of the different fractions retained on the sieves. 4 Apparatus Usual laboratory apparatus and in particular 4.1 to 4.6. 4.1 Balance, capable of weighing to the nearest 0,01 g. DIN EN 12948:2011-02 EN 12948:2010 (E) 6
33、 4.2 Mechanical shaker (sieving machine), capable of imparting both horizontal and vertical motion to material inside a nest of sieves, fitted with a lid with a water intake and a receiver with a water outlet when used for method B. NOTE Hand sieving can be carried out instead of mechanical sieving.
34、 4.3 Stainless steel woven wire test sieves, conforming to ISO 3310-1 and of appropriate nominal aperture sizes. 4.4 Stopwatch. 4.5 Soft brush. 4.6 Oven, capable of being controlled at (105 2) C. 5 Sampling and sample preparation Sampling is not part of the method specified in this document. A recom
35、mended sampling method is given in EN 1482-1. Sample preparation shall be carried out in accordance with EN 1482-2. 6 Procedure 6.1 Test portion The whole laboratory sample shall be divided in equal test portions of at least 100 g. The size of the test portions will vary according to the coarseness
36、of the laboratory sample and shall be in accordance with EN 1235:1995, Table 1, subject to a minimum of 100 g. 6.2 Method A 6.2.1 Preparation of test portions Dry wet samples if there is a possibility that blinding of the sieves could occur during the sieving. Dry the wet sample in an oven (4.6) at
37、(105 2) C for an appropriate period of time (see EN 12048). Check whether agglomeration occurs after drying by carrying out a preliminary sieving test. Use method B if agglomeration occurs. 6.2.2 Determination WARNING When sieving burnt or hydrated lime products, it is essential that precautions are
38、 taken to avoid inhalation and skin contact with the product. It is recommended that operations are carried out under a fume hood and appropriate gloves and eye protection are worn. 6.2.2.1 Carry out at least two single determinations on separate test portions prepared from the same laboratory sampl
39、e. 6.2.2.2 Select a maximum of seven test sieves (4.3) from the range of principal sizes listed in ISO 565 to cover the range of particle size expected. For granular liming materials perforated plates according to ISO 3310-2 may be used. DIN EN 12948:2011-02 EN 12948:2010 (E) 7 Assemble the sieves i
40、n ascending order of aperture size on top of the receiver. Weigh the test portion (6.1) to the nearest 0,01 g per 100 g of test portion, place it on the top sieve and fit the cover. 6.2.2.3 Place the sieve or the assembled nest of sieves on the mechanical shaker (4.2) and shake for exactly 10 min (u
41、se a stopwatch (4.4). Set the mechanical shaker to a medium vibration frequency throughout the sieving. 6.2.2.4 If a nest of sieves is used, remove the sieves from the nest and weigh the quantity retained on each sieve and in the receiver to the nearest 0,01 g. Remove particles caught in the mesh of
42、 the sieve by brushing the reverse side of the sieve. 6.2.2.5 If only one sieve is used, discard the undersize fraction that has passed through the sieve. Repeat the sieving process for exactly 1 min. If more than 0,2 g passes through the sieve, repeat the procedure as many times as necessary. Remov
43、e particles caught in the mesh of the sieve by brushing the reverse side of the sieve. Weigh the oversize fraction. 6.3 Method B 6.3.1 General Use an additional test portion to determine the moisture content in accordance with EN 12048. Carry out at least two single determinations on separate test p
44、ortions prepared from the same laboratory sample. 6.3.2 Determination 6.3.2.1 Non-granulated and non-agglomerated products 6.3.2.1.1 Select a maximum of seven test sieves (4.3) from the range of principal sizes listed in ISO 565 to cover the range of particle size expected. Assemble the sieves in as
45、cending order of aperture size on top of the receiver. Weigh the test portion (6.1) to the nearest 0,01 g per 100 g of test portion, place it on the top sieve and fit the lid with the intake for water. 6.3.2.1.2 Place the assembled nest of sieves on the mechanical shaker (4.2) and shake under a cont
46、inuous water flow of 2,0 l/min to 2,5 l/min for exactly 10 min (use a stopwatch (4.4). Set the mechanical shaker to a medium vibration frequency throughout the sieving. 6.3.2.1.3 Remove the sieves from the mechanical shaker and rinse the residues of each sieve quantitatively into separate 250 ml pre
47、-weighed beakers. Decant or pipette most of the water on the top of the material, ensuring that no material is spilled. Dry each of the oversize fractions in an oven (4.6) at (105 2) C and then weigh each fraction separately (see EN 12048). 6.3.2.2 Granulated and agglomerated products Weigh the test
48、 portion (6.1) to the nearest 0,01 g per 100 g of test portion and transfer it into a 800 ml beaker. DIN EN 12948:2011-02 EN 12948:2010 (E) 8 Add approximately 500 ml of water. Stir the granules for 10 min by means of a mechanical stirrer with a rotational speed not exceeding 800 min-1. Avoid grindi
49、ng. Rinse out the sample completely on to the top sieve and fit the lid with the intake for water. Continue according to 6.3.2.1.2 and 6.3.2.1.3. If the sum of individual masses is less than 95 % of the original mass, it should be assumed that the sample contains water-soluble constituents. 7 Expression of results 7.1 Method A 7.1.1 Record the masses of the fractions retained on the sieves and the receiver (see 6.2.2.4 and 6.2.2.5). 7.1.2 Calculate each mass fracti
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