1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12124:2012Chemicals used for treatmentof water intended for humanconsumption Sodium sulfiteCopyright European Committee for Standardization Provided by IHS under license wi
2、th CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN 12124:2012. It supersedes BS EN 12124:2005 which is withdrawn.The UK participation in its preparation was en
3、trusted to Technical Committee CII/59, Chemicals for drinking water treatment.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its corre
4、ct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 77781 3 ICS 71.100.80 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Str
5、ategy Committee on 28 February 2013.Amendments issued since publicationDate T e x t a f f e c t e dCopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EUROPEAN STANDA
6、RD NORME EUROPENNE EUROPISCHE NORM EN 12124 November 2012 ICS 71.100.80 Supersedes EN 12124:2005English Version Chemicals used for treatment of water intended for human consumption - Sodium sulfite Produits chimiques utiliss pour le traitement de leau destine la consommation humaine - Sulfite de sod
7、ium Produkte zur Aufbereitung von Wasser fr den menschlichen Gebrauch - Natriumsulfit This European Standard was approved by CEN on 23 September 2012. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status
8、 of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, Germ
9、an). 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-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia
10、, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and Unit
11、ed Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12124:2012:
12、ECopyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 2 Contents Page Foreword 3Introduction .41 Scope 52 Normative references 53 Description .54 Pur
13、ity criteria 75 Test methods 86 Labelling Transportation Storage . 14Annex A (informative) General information on sodium sulfite 15Bibliography . 17Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without lic
14、ense from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 3 Foreword This document (EN 12124:2012) has been prepared by Technical Committee CEN/TC 164 “Water supply”, the secretariat of which is held by AFNOR. This European Standard shall be given the status of a national standard, either by publication o
15、f an identical text or by endorsement, at the latest by May 2013, and conflicting national standards shall be withdrawn at the latest by May 2013. Attention 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 hel
16、d responsible for identifying any or all such patent rights. This document supersedes EN 12124:2005. Significant technical differences between this edition and EN 12124:2005 are as follows: Modification of 6.2 on labelling, deletion of the reference to EU Directive 80/778/EEC of 15 July 1980 in orde
17、r to take account of the latest Directive in force. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland
18、, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Copyright European Committee for St
19、andardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 4 Introduction In respect of potential adverse effects on the quality of water intended for human consumption caused by the product
20、 covered by this European Standard: a) this European Standard provides no information as to whether the product may be used without restriction in any of the Member States of the EU or EFTA; b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national re
21、gulations concerning the use and/or the characteristics of this product remain in force. NOTE Conformity with this European Standard does not confer or imply acceptance or approval of the product in any of the Member States of the EU or EFTA. The use of the product covered by this European Standard
22、is subject to regulation or control by National Authorities. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 5 1 Scope This European Standard is
23、 applicable to sodium used for treatment of water intended for human consumption .It describes the characteristics and specifies the requirements of sodium sulfite and refers to the corresponding analytical methods. It gives information for its use in water treatment. 2 Normative references The foll
24、owing documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN ISO 3696, Wa
25、ter for analytical laboratory use Specification and test methods (ISO 3696) ISO 418, Photography Processing chemicals Specifications for anhydrous sodium sulfite ISO 3165, Sampling of chemical products for industrial use Safety in sampling ISO 5993, Sodium hydroxide for industrial use Determination
26、of mercury content Flameless atomic absorption spectrometric method ISO 6206, Chemical products for industrial use Sampling Vocabulary ISO 6332, Water quality Determination of iron Spectrometric method using 1,10-phenanthroline ISO 6353-1, Reagents for chemical analysis Part 1: General test methods
27、ISO 8213, Chemical products for industrial use Sampling techniques Solid chemical products in the form of particles varying from powders to coarse lumps ISO 22743, Water quality Determination of sulfates Method by continuous flow analysis (CFA) 3 Description 3.1 Identification 3.1.1 Chemical name So
28、dium sulfite. 3.1.2 Synonym or common name Sodium sulfite. 3.1.3 Relative molecular mass 126,04. 3.1.4 Empirical formula Na2SO3.Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS
29、 EN 12124:2012EN 12124:2012 (E) 6 3.1.5 Chemical formula Na2SO3.3.1.6 CAS-Registry Number 1)7757-83-7. 3.1.7 EINECS reference 2)231-821-4. 3.2 Commercial form The product is a crystalline powder. 3.3 Physical properties 3.3.1 Appearance and odour The product is a white, fine crystalline, odourless p
30、owder. 3.3.2 Density The density of the product is 2,63 g/cm at 20 C. The bulk density is 1,2 g/cm to 1,5 g/cm at 20 C. 3.3.3 Solubility in water The solubility of the product in water is 250 g/l at 20 C. 3.3.4 Vapour pressure Not applicable. 3.3.5 Boiling point at 100 kPa 3)The product decomposes a
31、bove 230 C. 3.3.6 Crystallisation point See 3.3.5. 3.3.7 Specific heat Not known. 1) Chemical Abstracts Service Registry Number. 2) European Inventory of Existing Commercial Chemical Substances. 3) 100 kPa = 1 bar. Copyright European Committee for Standardization Provided by IHS under license with C
32、ENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 7 3.3.8 Viscosity, dynamic Not applicable. 3.3.9 Critical temperature Not applicable. 3.3.10 Critical pressure Not applicable. 3.3.11 Physical hardness Not applicable. 3.4 Chemical
33、properties The pH value of a saturated aqueous solution of sodium sulfite is in the range of 9,7 to 10,2. At elevated temperatures ( 100 C) sulfur dioxide is generated. On contact with air, small amounts of sodium sulfate are formed. Sodium sulfite releases sulfur dioxide when mixed with acids. Sodi
34、um sulfite reacts violently with oxidising agents; e.g. with sodium hypochlorite or hydrogen peroxide. 4 Purity criteria 4.1 General This European Standard specifies the minimum purity requirements for sodium sulfite used for the treatment of water intended for human consumption. Limits are given fo
35、r impurities commonly present in the product. Depending on the raw material and the manufacturing process other impurities may be present and, if so, this shall be notified to the user and when necessary, to relevant authorities. Users of this product should check the national regulations in order t
36、o clarify whether it is of appropriate purity for treatment of water intended for human consumption, taking into account raw water quality, required dosage, contents of other impurities and additives used in the product not stated in this product standard. Limits have been given for impurities and c
37、hemical parameters where these are likely to be present in significant quantities from the current production process and raw materials. If the production process or raw materials leads to significant quantities of impurities, by-products or additives being present, this shall be notified to the use
38、r. 4.2 Composition of commercial product The content of sodium sulfite shall not be less than a mass fraction of 95 %. 4.3 Impurities and main by-products The content of sodium sulfate shall not exceed a mass fraction of 5 %. The content of iron (Fe) shall not exceed 25 mg/kg. Copyright European Com
39、mittee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 8 4.4 Chemical parameters The product shall conform to the requirements specified in Table 1. Table 1 Chemical paramet
40、ers Parameter Limit mg/kg of commercial product Antimony (Sb) max 2 Arsenic (As) max 1 Cadmium (Cd) max 1 Chromium (Cr) max 1 Lead (Pb) max 2 Mercury (Hg) max 0,5 Nickel (Ni) max 1 Selenium (Se) max 1 NOTE Pesticides and polycyclic aromatic hydrocarbons and cyanides ( CN-) are not relevant in sodium
41、 sulfite because the raw materials used in the manufacturing are free of them. For parametric values of sodium sulfite on trace metal content in drinking water, see 1. 5 Test methods 5.1 Sampling Observe the general recommendations of ISO 3165 and take account of ISO 6206. Prepare the laboratory sam
42、ple(s) required by the relevant procedure described in ISO 8213. 5.2 Analyses 5.2.1 Main product The sodium sulfite content shall be determined in accordance with ISO 418. NOTE Both methods, direct titration and back titration, can be used. 5.2.2 Impurities 5.2.2.1 Sulfate The content of sodium sulf
43、ate (Na2SO4) shall be determined in accordance with ISO 22743. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 9 5.2.2.2 Iron (Fe) The content o
44、f iron (Fe) shall be determined in accordance with ISO 6332 (spectrometric method). 5.2.3 Chemical parameters 5.2.3.1 General The content of chemical parameters shall be determined using the procedures specified in Table 2: Table 2 Procedures for the determination of chemical parameters Element Refe
45、rence Method Wavelength (nm) Flame As see 5.2.3.3 Hydride AAS 193,7 n.a.Sb see 5.2.3.3 Hydride AAS 217,6 n.a. Cd ISO 6353-1 GM 29see 5.2.3.2 AAS 228,8 air-acetylene Cr ISO 6353-1 GM 29see 5.2.3.2 AAS 357,8 air-acetylene Pb ISO 6353-1 GM 29see 5.2.3.2 AAS 217,0 or 283,3 air-acetylene Ni ISO 6353-1 GM
46、 29see 5.2.3.2 AAS 232,0 oxidising acetylene-air Se see 5.2.3.3 Hydride AAS 196,0 n.a.Hg in accordance withISO 5993 flameless AAS 253,6 n.a. AAS = Atomic Absorption Spectroscopy. n.a. = not applicable. 5.2.3.2 Determination of cadmium (Cd), chromium (Cr), lead (Pb) and nickel (Ni) 5.2.3.2.1 Principl
47、e The elements cadmium (Cd), chromium (Cr), lead (Pb) and nickel (Ni) are determined using atomic absorption spectrometry with the standard additions technique. 5.2.3.2.2 Reagents All reagents shall be of a recognised analytical grade and the water used shall conform to the grade 3 specified in EN I
48、SO 3696. Copyright European Committee for Standardization Provided by IHS under license with CENNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BS EN 12124:2012EN 12124:2012 (E) 10 5.2.3.2.2.1 Standard solution (100 g/l Cd, Cr ,Pb or Ni). The standard solution shall be freshly prepared on the day of use by individual dilution of a stock solution. This stock solution with a Cd, Cr, Pb or Ni content of at least 1 mg/l shall be made by diluti
