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1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 974 : 1997 The Euro
2、pean Standard EN 974 : 1997 has the status of a British Standard ICS 71.100.80 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Chemicals used for treatment of water intended for human consumption Phosphoric acid Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 03:21:07 G
3、MT+00:00 2006, Uncontrolled Copy, (c) BSI This British Standard, having been prepared under the direction of the Sector Board for Materials and Chemicals, was published under the authority of the Standards Board and comes into effect on 15 December 1997 BSI 1997 ISBN 0 580 28648 7 BS EN 974 : 1997 A
4、mendments issued since publication Amd. No.DateText affected National foreword This British Standard is the English language version of EN 974 : 1997. The UK participation in its preparation was entrusted to Technical Committee CII/59, Chemicals for drinking water treatment, which has the responsibi
5、lity to: aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organization
6、s represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled International Standards Corre
7、spondence Index, or by using the Find facility of the BSI Standards Electronic Catalogue. The United Kingdom voted against the acceptance of this standard at the Formal Vote stage. The UK objections related to changes introduced after the CEN Enquiry stage and were as follows. a) The instructions gi
8、ven in 5.1.1 and 5.1.2 were intended for the sampling of non-hazardous liquid products and are not suitable for sampling hazardous products such as concentrated phosphoric acid. The sampling of phosphoric acid is described in detail in ISO 4285, to which reference is already made. The instructions i
9、n 5.1.1 and 5.1.2 contradict those in ISO 4285 and are completely inappropriate. b) In 5.2.3.1 and 5.2.3.2.1 reference is made to ISO 6353-1 General Method 29 for the determination of certain toxic substances. However, General Method 29 does not give any details of the procedure to determine any of
10、these elements (by atomic absorption spectroscopy) and the references to it are therefore very confusing. The necessary procedure is described in 5.2.3.2.2. It is the strong recommendation of the BSI technical committee that sampling is carried out in accordance with ISO 4285. Additional information
11、 Article 8 of the Council of the European Community Directive 80/778/EEC relating to the quality of water intended for human consumption requires Member States to ensure that substances used in the preparation of drinking water do not cause any contravention of the maximum admissible concentrations
12、prescribed in annex 1 to the Directive. This requirement is given effect in England and Wales by regulation 25 of the Water Supply (Water Quality) Regulations 1989 (similar provisions apply in Scotland and Northern Ireland). Regulation 25 makes provision for attaching conditions of use to chemicals
13、which are authorized for use in public water supplies. Details of conditions of use are contained in the Secretary of States List of Approved Products published by the Drinking Water Inspectorate, Room B153, Romney House, 43 Marsham Street, London SW1P 3PY. Compliance with a British Standard does no
14、t of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 12, an inside back cover and a back cover. Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 03:21:07 GMT+00:00 2006, Uncontrolled Cop
15、y, (c) BSI CEN European Committee for Standardization Comite Europe en de Normalisation Europa isches Komitee fu r Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1997 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. E
16、N 974 : 1997 E EUROPEAN STANDARDEN 974 NORME EUROPE ENNE EUROPA ISCHE NORM July 1997 ICS 71.100.81 Descriptors: Potable water, water treatment, chemical compounds, phosphoric acid, description, physical properties, chemical properties, impurities, toxic substances, tests, labelling, storage English
17、version Chemicals used for treatment of water intended for human consumption Phosphoric acid Produits chimiques utilise s pour le traitement de leau destine e a la consommation humaine Acide phosphorique Produkte zur Aufbereitung von Wasser fu r den menschlichen Gebrauch Phosphorsa ure This European
18、 Standard was approved by CEN on 1997-07-05. CEN 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
19、 such national standards may be obtained on application to the Central Secretariat 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 langu
20、age and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, S
21、witzerland and United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 03:21:07 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 2 EN 974 : 1997 BSI 1997 Foreword This European Standard has been prepared by Technical Committee CEN/TC 164, Water supply, the Secretariat of which is held
22、by AFNOR. 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 January 1998, and conflicting national standards shall be withdrawn at the latest by January 1998. According to the CEN/CENELEC Internal R
23、egulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and t
24、he United Kingdom. Contents Page Foreword2 Introduction3 1Scope3 2Normative references3 3Description3 3.1Identification3 3.2Commercial forms3 3.3Physical properties3 3.4Chemical properties4 4Purity criteria4 4.1Composition of commercial product4 4.2Impurities and main by-products4 4.3Toxic substance
25、s4 5Test methods5 5.1Sampling5 5.2Analyses5 6Labelling Transportation Storage8 6.1Means of delivery8 6.2Risk and safety labelling according to the EU Directives9 6.3Transportation regulations and labelling9 6.4Marking9 6.5Storage9 Annex A (informative) General information on phosphoric acid10 Annex
26、B (informative) Determination of concentration by measurement of density10 Annex C (informative) Bibliography12 Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 03:21:07 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 3 EN 974 : 1997 BSI 1997 1)Chemical Abstracts Service Registry Number. 2)Eur
27、opean Inventory of Existing Commercial Chemical Substances. 3)100 Pa = 1 mbar. 100 kPa = 1 bar. Introduction In respect of potential adverse effects on the quality of water intended for human consumption, caused by the product covered by this standard: 1) this standard provides no information as to
28、whether the product may be used without restriction in any of the Member States of the EU or EFTA; 2) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations concerning the use and/or the characteristics of this product remain in force. 1 S
29、cope This European Standard is applicable to phosphoric acid used for treatment of water intended for human consumption. It describes the characteristics and specifies the requirements and the corresponding test methods for phosphoric acid. It gives information on its use in water treatment. 2 Norma
30、tive references This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of
31、 any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. EN ISO 3696Water for analytical laboratory use Specification and test methods (ISO 3696 : 1987) ISO 3165
32、Sampling of chemical products for industrial use Safety in sampling ISO 3706Phosphoric acid for industrial use (including foodstuffs) Determination of total phosphorus (V) oxide content Quinoline phosphomolybdate gravimetric method ISO 4285Phosphoric acid for industrial use Guide to sampling techniq
33、ues ISO 5993Sodium hydroxide for industrial use Determination of mercury content Flameless atomic absorption spectrometric method ISO 6206Chemical products for industrial use Sampling Vocabulary ISO 6353-1Reagents for chemical analysis Part 1 : General test methods ISO 6353-2Reagents for chemical an
34、alysis Part 2 : Specifications First series 3 Description 3.1 Identification 3.1.1 Chemical name Phosphoric acid. 3.1.2 Synonym or common name Orthophosphoric acid. 3.1.3 Relative molecular mass 98. 3.1.4 Empirical formula H3PO4. 3.1.5 Chemical formula H3PO4. 3.1.6 CAS Registry Number1) 7664-38-2. 3
35、.1.7 EINECS reference2) 231-633-2. 3.2 Commercial forms Phosphoric acid is supplied as a concentrated solution, the usual concentrations being 75 % (m/m), 80 % (m/m) or 85 % (m/m) of phosphoric acid. 3.3 Physical properties 3.3.1 Appearance The product is a clear syrupy liquid. 3.3.2 Density 1,57 g/
36、ml at 20 C for phosphoric acid concentration of 75 % (m/m). 1,69 g/ml at 20 C for phosphoric acid concentration of 85 % (m/m). 3.3.3 Solubility in water Miscible at all concentrations. 3.3.4 Vapour pressure Below 3 Pa3)at 20 C. 3.3.5 Boiling point at 100 kPa3) 135 C for phosphoric acid concentration
37、 of 75 % (m/m). 158 C for phosphoric acid concentration of 85 % (m/m). Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 03:21:07 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 4 EN 974 : 1997 BSI 1997 3.3.6 Melting point 20 C for phosphoric acid concentration of 75 % (m/m). + 21 C for phospho
38、ric acid concentration of 85 % (m/m). 3.3.7 Specific heat 2,27 kJ/(kgK) at 20 C for phosphoric acid concentration of 75 % (m/m). 2,07 kJ/(kgK) at 20 C for phosphoric acid concentration of 85 % (m/m). 3.3.8 Viscosity, dynamic At room temperature phosphoric acid is a syrupy liquid. Its viscosity depen
39、ds on temperature. The viscosity of a 75 % (m/m) solution of phosphoric acid at 20 C is 22 mPas. The viscosity of a 85 % (m/m) solution of phosphoric acid at 20 C is 48 mPas. 3.3.9 Critical temperature Not applicable. 3.3.10 Critical pressure Not applicable. 3.3.11 Physical hardness Not applicable.
40、3.4 Chemical properties Phosphoric acid is a strong acid. A solution of 1 g/l phosphoric acid has a pH value of 1. Concentrated phosphoric acid reacts violently with bases, nitrates, chlorates, sulfites. 4 Purity criteria Limits have been given for impurities and toxic substances where these are lik
41、ely to be present in significant quantities from the current production process and raw materials. If a change in the production process or raw materials leads to significant quantities of other impurities or by-products being present, this shall be notified to the user. 4.1 Composition of commercia
42、l product The following requirements shall apply to phosphoric acid: appearance: clear, no sediment; if sold as concentrated acid, the phosphoric acid content shall not be less than 75 % (m/m); the product shall contain the stated concentration of phosphoric acid within1 % (m/m). 4.2 Impurities and
43、main by-products The product shall conform to the requirements specified in table 1. Table 1. Impurities ImpurityLimit in H3PO4 (mg/kg) Sulfuric acid (H2SO4)max. 500 Iron (Fe)max. 20 4.3 Toxic substances NOTE. For the purpose of this standard, Toxic substances are those defined in the EU Directive 8
44、0/778/EEC of July 15, 1980 (see C.1). The content of toxic substances shall conform to the requirements specified in table 2. Licensed Copy: sheffieldun sheffieldun, na, Tue Nov 07 03:21:07 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page 5 EN 974 : 1997 BSI 1997 Table 2. Toxic substances ParameterLi
45、mit in H3PO4 (mg/kg) Antimony (Sb)max. 4 Arsenic (As)max. 2 Cadmium (Cd)max. 0,5 Chromium (Cr)max. 4 Lead (Pb)max. 4 Mercury (Hg)max. 0,5 Nickel (Ni)max. 4 Selenium (Se)max. 1 NOTE. Pesticides and polycyclic aromatic hydrocarbons as listed in EEC Directive 80/778/EEC are not relevant in phosphoric a
46、cid. Cyanide (CN2) is not relevant due to the acidity of phosphoric acid. 5 Test methods 5.1 Sampling Observe the general recommendation in ISO 3165 and ISO 4285 and take account of ISO 6206. 5.1.1 Sampling from drums and bottles 5.1.1.1 General 5.1.1.1.1 Mix the contents of the container to be samp
47、led by shaking the container, by rolling it or by rocking it from side to side, taking care not to damage the container or spill any of the liquid. 5.1.1.1.2 If the design of the container is such (for example, a narrow-necked bottle) that it is impracticable to use a sampling implement, take a samp
48、le by pouring after the contents have been thoroughly mixed. Otherwise, proceed as described in 5.1.1.1.3. 5.1.1.1.3 Examine the surface of the liquid. If there are signs of surface contamination, take samples from the surface as described in 5.1.1.2; otherwise, take samples as described in 5.1.1.3.
49、 5.1.1.2 Surface sampling Take a sample using a suitable ladle. Lower the ladle into the liquid until the rim is just below the surface, so that the surface layer runs into it. Withdraw the ladle just before it fills completely and allow any liquid adhering to the ladle to drain off. If necessary, repeat this operation so that, when the other selected containers have been sampled in a similar manner, the total volume of sample required for subsequent analysis is obtained. 5.1.1.3 Bottom sampling Ta
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