SANS 459-2008 Lime for chemical and metallurgical purposes《化学和冶金用石灰》.pdf

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1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA

2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any

3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-21397-8 SANS 459:2008Edition 1.5Any reference to SABS 459 is deemedto be a reference to this standard(Government Notice No. 1373 of 8 Nove

4、mber 2002)SOUTH AFRICAN NATIONAL STANDARD Lime for chemical and metallurgical purposes Published by Standards South Africa 1 dr lategan road groenkloof private bag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa SANS 459:2008

5、Edition 1.5 Table of changes Change No. Date Scope Amdt 1 1959 Amended to change the reagent for available lime test. Amdt 2 1976 Amended to replace non-metric units by metric units and to add a footnote to the sampling section. Amdt 3 1983 Amended to change the requirements and test procedure for a

6、vailable calcium oxide. Amdt 4 1989 Amended to convert the standard specification to a specification.Amdt 5 2008 Amended to change the designation from SABS to SANS, with no technical changes. Foreword This South African standard was approved by National Committee StanSA SC 5140.01C, Detergents, pol

7、ishes and other chemicals Bleaches and other chemical substances, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This document was published in April 2008. This document supersedes SABS 459:1955 (edition 1). Preface Lime cover by this sp

8、ecification is intended for chemical and metallurgical purposes only. Attention is drawn to the fact that lime intended for in the building industry should comply with the requirements of SANS 523, Limes for use in building. SANS 459:2008 Edition 1.5 1 Contents Page Foreword 1 Scope . 3 2 Definition

9、s 3 3 Physical and chemical requirements . 3 4 Labelling and marking 5 5 Sampling and compliance with the specification . 5 6 Physical test . 7 6.1 Sieve grading 7 7 Chemical analysis 7 7.1 Preparation of sample . 7 7.2 Loss on ignition . 7 7.3 Silica and insoluble mineral matter . 8 7.4 Iron, alumi

10、nium and chromium oxides 9 7.5 Calcium oxide 9 7.6 Magnesium oxide 10 7.7 Sulphur trioxide . 11 7.8 Manganese . 12 7.9 Phosphorus . 13 7.10 Available calcium lime . 15 7.11 Carbon dioxide 17 7.12 Carbon . 19 SANS 459:2008 Edition 1.5 2 This page intentionally left blank SANS 459:2008 Edition 1.5 3 L

11、ime for chemical and metallurgical purposes 1 Scope 1.1 This specification covers the following types and grades of quicklime and hydrated lime for chemical and metallurgical use: Quicklime: Type I, calcium quicklime Type II, magnesian quicklime Type III, dolomitic quicklime Hydrated lime: Type I, c

12、alcium hydrated lime, Grade I, Grade II and Grade III Type If, magnesian hydrated lime Type III, dolomitic hydrated lime 2 Definitions 2.1 For the purposes of this specification the following definitions shall apply: hydrated lime Quicklime which has been suitably treated with water or steam and has

13、 reacted therewith lot the quantity of material of one type and grade submitted for inspection at any one time. If the material is supplied in truckloads, each truckload shall be taken as a lot Amdt 2 quicklime Calcined limestone consisting essentially of calcium oxide or calcium and magnesium oxide

14、s which will slake with water 3 Physical and chemical requirements 3.1 Quicklime 3.1.1 The quicklime shall have the relevant physical and chemical properties specified in table 1. Amdt 2 SANS 459:2008 Edition 1.5 4 Table 1 Physical and chemical properties of quicklime 1 2 3 4 Type I Type II Type III

15、 Silica and insoluble mineral matter, % (m/m), max. . 3,0 6,0 8,0 Total calcium oxide, % (m/m), min. . 88,0 78,0 Total calcium plus magnesium oxides, % (m/m), min. 80,0 Available calcium oxide, % (m/m), min. 88,0 78,0 Magnesium oxide, % (m/m), max. . 2,5 15,0 42,0 Magnesium oxide, % (m/m), min. 30,0

16、 Sulphate (as SO3), % (m/m), max. 1,0 1,0 1,0 R203(R = Fe, Al, Cr and Mn) % (m/m), max. . 2,0 4,0 Size of lumps. . To be agreed upon between buyer and seller *The available calcium oxide content of Type III quicklime and Type III hydrated lime is left as a matter to be agreed upon between buyer and

17、seller. Attention is drawn to the fact that the total available alkalinity of a lime is derived from the calcium oxide or hydroxide content and not from the magnesium oxide or hydroxide content. Amdt 2, amdt 3 3.1.2 Additional requirements for Type I quicklime (a) If intended for use in the carbide

18、industry, Type I quicklime shall contain not more than 0,02, % (m/m) phosphorus. Amdt 2 (b) If intended for use in cyanide treatment, the carbon content of Type I quicklime shall be agreed upon between buyer and seller. 3.2 Hydrated lime Hydrated lime shall have the relevant physical and chemical pr

19、operties specified in table II. Amdt 2 SANS 459:2008 Edition 1.5 5 Table 2 Physical and chemical properties of hydrated lime 1 2 3 4 5 6 Type I Grade I Grade II Grade III Type II Type III Silica and insoluble mineral matter, % (m/m), max. . 2,0 3,0 3,5 4,5 6,0 Available calcium oxide, % (m/m), min.

20、68,0 66,0 64,0 60,0 Total calcium plus magnesium oxides, % (m/m) , min. Magnesium oxide, % (m/m) , max. . 64,0 Magnesium oxide, per cent, min. 2,0 2,0 2,0 10,0 31,0 Carbon dioxide, % (m/m) , max. . 3,0 3,0 4,0 3,0 5,0 Residue retained on a sieve of nominal operture size 150 m % (m/m) , max. 5,0 8,0

21、12,0 10,0 10,0 *The available calcium oxide content of Type III quicklime and Type III hydrated lime is left as a matter to be agreed upon between buyer and seller. Attention is drawn to the fact that the total available alkalinity of a lime is derived from the calcium oxide or hydroxide content and

22、 not from the magnesium oxide or hydroxide content. Amdt 2, amdt 3 4 Labelling and marking 4.1 The following information shall be indelibly marked either on each container or on a label attached to each container. a) the name “Hydrated Lime for Chemical and Metallurgical Purposes“or “Quicklime for C

23、hemical and Metallurgical Purposes“; b) the manufacturers name or trade mark; c) net mass of contents when packed; and d) the type and, when relevant, the grade. Amdt 2 4.2 When tie-on labels are used they shall be of sufficient strength to withstand normal handling 5 Sampling and compliance with th

24、e specification*5.1 Sampling The following sampling procedure shall be applied when it is necessary to determine whether a lot complies with the requirements of this specification *This section applies to the sampling for inspection and testing before acceptance or rejection of single lots (consignm

25、ents) in cases where no information about the implementation of quality control or testing during manufacture is available to help in assessing the quality of the lot. It is also used as the procedure for adjudicating in cases of dispute. Amdt 2 SANS 459:2008 Edition 1.5 6 5.1 General Amdt 2 Samplin

26、g shall be conducted as expeditiously as possible in order to avoid undue exposure of the material to the air. The breaking down and coning and quartering of bulk samples shall be carried out under cover. Samples shall not be taken from broken packages. Sampling shall be carried out at the time of d

27、ispatch from the manufacturers works. 5.1.2 Sampling of lump quicklime delivered in bulk Amdt 2 a) Take approximately equal portions from at least 20 different positions in order to form a composite sample of at least 100 kg. The portions shall be taken in such a manner that the composite sample rep

28、resents an average of all parts of the lot and shall not contain a disproportionate share of the top or bottom layers. b) Break the sample down to 25 mm lumps or finer and after thorough mixing on a clean, dry, steel surface, cone and quarter1)down to approximately 10 kg. Crush this sample to 6 mm o

29、r finer lumps and cone and quarter down to 2,5 kg. Crush this sample to pass a sieve of nominal aperture size 1,70 mm, mix thoroughly and cone and quarter down to approximately 600 g. Divide this sample into three 200 g representative portions and immediately place each portion in an airtight contai

30、ner of such size that it is nearly filled by the sample and mark with full details and date of sampling. Submit one sample to the laboratory for test and one sample to the manufacturer and keep the third sample for reference. 5.1.3 Sampling of lump quicklime delivered in containers Amdt 2 If the lot

31、 consists of ten or less containers, sample every container. If the lot consists of more than ten containers, sample ten containers taken at random from the lot. Take approximately equal representative quantities of not less than 10 kg from each, combine into a composite sample and proceed as descri

32、bed in 5.1.2(b). 5.1.4 Sampling of powdered quicklime and hydrated lime delivered in bulk Amdt 2a) Take approximately equal portions from at least 20 different positions in order to form a composite sample of at least 10 kg. The portions shall be taken in such a manner that the composite sample repr

33、esents an average of all parts of the lot and shall not contain a disproportionate share of the top or bottom layers. b) Mix the composite sample thoroughly on a clean, dry, steel surface and cone and quarter down to approximately 2,5 kg. Divide into three approximately equal representative portions

34、, immediately place each portion in an airtight container of such size that it is nearly filled by the sample and mark with full details including the date of sampling. Submit one sample to the laboratory for test, one sample to the manufacturer and keep the third sample for reference. 5.1.5 Samplin

35、g of powdered quicklime and hydrated lime delivered in containers Amdt 2 If the lot consists of ten or less containers, sample each container. If the lot consists of more than ten containers, sample ten containers taken at random from the lot. Take approximately equal representative quantities of no

36、t less than 1 kg from each container, combine into a composite sample and proceed in accordance with 5.1.4(b). 1)Instead of coning and quartering, a riffle sampler, which will give equally representative samples, may be used. SANS 459:2008 Edition 1.5 7 5.1.6 The samples taken in accordance with 5.1

37、.2 up to and including 5.1.5, shall be taken as being representative of the lot. 5.2 Compliance with specification If a sample taken in accordance with 5.1.2 up to and including 5.1.5 meets the requirements, the lot represented by the sample shall be deemed to comply with the specification. 6 Physic

38、al test 6.1 Sieve grading 6.1.1 Apparatus Sieve of nominal aperture size 150 m and of diameter 200 mm. Amdt 2 6.1.2 Procedure Weigh 200 g of hydrated lime into the sieve and wash through with a fine stream of water. Continue washing until the water coming through the sieve is clear. In no case shall

39、 the washing be continued for more than 30 min. Dry the residue at 100 to 120C to constant mass. 6.1.3 Calculation Sieve of nominal aperture size 150 m, % (m/m) = B100A where A = mass of residue found, in grams, and B = mass of sample taken, in grams. Amdt 2 7 Chemical analysis 7.1 Preparation of sa

40、mple Reduce the sample submitted for test to about 150 g by coning and quartering. Grind this sample to approximately 150 m size but do not actually sieve, keep in a tightly stoppered bottle and use for the chemical analysis. Amdt 2 7.2 Loss on ignition 7.2.1 Procedure Accurately weigh out 1 g of qu

41、icklime into a previously ignited and weighed platinum crucible, cover and ignite to constant mass at 1,100 C. SANS 459:2008 Edition 1.5 8 7.2.2 Calculation Loss on ignition, % (m/m) = B100A where A = loss in mass, in grams, and B = mass of sample taken, in grams. Amdt 2 7.3 Silica and insoluble min

42、eral matter 7.3.1 Procedure Accurately weigh approximately 0,5 g of the sample into an evaporating dish, mix to a thin slurry with distilled water, cover with a watch-glass, add 5 to 10 mL of hydrochloric acid and digest with the aid of gentle heat and agitation until solution is complete. Evaporate

43、 to dryness on a waterbath and heat in an oven at 110 to 120 C for 1 h. Cool, add 5 to 10 mL of hydrochloric acid, allow to stand for a few minutes, add an equal volume of distilled water, cover and digest on a waterbath for 10 min. Filter, wash the residue with hot hydrochloric acid (1:99) and fina

44、lly wash twice with hot distilled water. Evaporate the filtrate to dryness, heat at 110 to 120 C for 1 h, extract with hydrochloric acid as before and filter through a second and smaller paper. Reserve the filtrate. Transfer the wet filter papers containing the residue to a weighed platinum crucible

45、, char carefully without allowing the paper to inflame and finally ignite to constant mass at 1,100 C. Amdt 2 7.3.2 Blank Make a blank determination following the same procedure and using the same amounts of reagents and correct the results obtained in the analysis accordingly. 7.3.3 Calculation Sil

46、ica and insoluble mineral matter, % (m/m) = B100A where A = mass of silica and insoluble mineral matter found, in grams, and B = mass of sample taken, in grams. Amdt 2 SANS 459:2008 Edition 1.5 9 7.4 Iron, aluminium and chromium oxides 7.4.1 Reagent Methyl red indicator solution. Dissolve 0,1 g of t

47、he free acid in 60 mL of ethyl alcohol and make up to 100 mL with distilled water. 7.4.2 Procedure To the filtrate, reserved in accordance with 7.3.1, add a few drops of bromine water or nitric acid and boil until all traces of bromine or chlorine have been removed. Add hydrochloric acid, if necessa

48、ry, to ensure a total of 10 to 15 mL of the acid and dilute to 200 mL. Add a few drops of methyl red solution, heat to boiling and neutralize with ammonium hydroxide (diluted towards the end) until the colour of the indicator turns a distinct yellow. Boil for 1 to 2 min, allow to settle, filter and

49、immediately wash the precipitate two or three times with hot ammonium chloride solution (20 g per litre). Reserve the filtrate. Dissolve the precipitate from the filter paper with hot hydrochloric acid (1:3), the solution passing into the beaker in which the precipitation was made and wash the paper thoroughly with hot distilled water. Boil the solution to expel any trace of chlorine and precipitate with ammonium hydroxide as before. Filter and wash with hot ammonium chloride solution (20 g per litre). Comb