1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 12126:2012Chemicals used for treatmentof water intended for humanconsumption LiquefiedammoniaBS EN 12126:2012 BRITISH STANDARDNational forewordThis British Standard is the
2、UK implementation of EN 12126:2012. Itsupersedes BS EN 12126:2005 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee CII/59, Chemicals for drinking water treatment.A list of organizations represented on this committee can beobtained on request to its secre
3、tary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 77782 0ICS 13.060.20; 71.100.80Compliance with a British Standar
4、d cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 January 2013.Amendments issued since publicationDate Text affectedBS EN 12126:2012EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12126 Nove
5、mber 2012 ICS 71.100.80 Supersedes EN 12126:2005English Version Chemicals used for treatment of water intended for human consumption - Liquefied ammonia Produits chimiques utiliss pour le traitement de leau destine la consommation humaine - Ammoniac liqufiProdukte zur Aufbereitung von Wasser fr den
6、menschlichen Gebrauch - Ammoniak, flssig 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 of a national standard without any alteratio
7、n. 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, German). A version in any other language made by
8、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, Cyprus, Czech Republic, Denmark, Estonia, F
9、inland, 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 United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZ
10、ATION 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 12126:2012: EBS EN 12126:2012EN 12126:2012 (E) 2 Contents
11、 Page Foreword 3Introduction .41 Scope 52 Normative references 53 Description .54 Purity criteria 75 Test methods 86 Labelling Transportation Storage . 12Annex A (informative) General information on liquefied ammonia 16Annex B (normative) General rules relating to safety . 17Bibliography . 18BS EN 1
12、2126:2012EN 12126:2012 (E) 3 Foreword This document (EN 12126:2012) 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 of an identical text or by
13、 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 held responsible for identif
14、ying any or all such patent rights. This document supersedes EN 12126:2005. The significant technical differences between this edition and EN 12126:2005 are as follows: Modification of 6.2 on labelling, deletion of the reference to EU Directive 80/778/EEC of 15 July 1980 in order to take account of
15、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, Former Yugoslav Rep
16、ublic 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. BS EN 12126:2012EN 12126:2012 (E) 4 Introduction In resp
17、ect of potential adverse effects on the quality of water intended for human consumption caused by the product 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;
18、b) 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. NOTE Conformity with this European Standard does not confer or imply acceptance or approval of the pro
19、duct in any of the Member States of the EU or EFTA. The use of the product covered by this European Standard is subject to regulation or control by National Authorities. BS EN 12126:2012EN 12126:2012 (E) 5 1 Scope This European Standard is applicable to liquefied ammonia used for treatment of water
20、intended for human consumption. It describes the characteristics and specifies the requirements of liquefied ammonia and refers to the corresponding analytical methods. It gives information for its use in water treatment. It also determines the rules relating to the safe handling and use of liquefie
21、d ammonia (see Annex B). 2 Normative references The following 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 docu
22、ment (including any amendments) applies. EN ISO 3696, Water for analytical laboratory use Specification and test methods (ISO 3696) ISO 7103, Liquefied anhydrous ammonia for industrial use Sampling Taking a laboratory sample ISO 7105, Liquefied anhydrous ammonia for industrial use Determination of w
23、ater content Karl Fischer Method ISO 7106, Liquefied anhydrous ammonia for industrial use Determination of oil content Gravimetric and infra-red spectrometric methods 3 Description 3.1 Identification 3.1.1 Chemical name Ammonia liquefied, anhydrous. 3.1.2 Synonym or common name Ammonia. 3.1.3 Relati
24、ve molecular mass 17,03. 3.1.4 Empirical formula NH3. 3.1.5 Chemical formula NH3. 3.1.6 CAS Registry Number 1)7664-41-7. 1) Chemical Abstracts Service Registry Number. BS EN 12126:2012EN 12126:2012 (E) 6 3.1.7 EINECS reference 2)231-635-3. 3.2 Commercial form The product is available as liquefied ga
25、s. 3.3 Physical properties 3.3.1 Appearance and odour The product is colourless liquid with a characteristic pungent odour. 3.3.2 Density The density of the gas is 0,771 g/l at 101,3 kPa 3)and 0 C. The density of the liquid is 0,682 g/ml at 101,3 kPa and -34 C, and 0,61 g/ml at 850 kPa and 20 C. 3.3
26、.3 Solubility (in water) The solubility of the product in water is 900 g/l at 0 C, 520 g/l at 20 C, and 407 g/l at 30 C. 3.3.4 Vapour pressure The vapour pressure of the product is 400 kPa at 0 C, 850 kPa at 20 C and 2 035 kPa at 50 C. 3.3.5 Boiling point at 100 kPa 3)The boiling point of the produc
27、t is -33,4 C at 101,3 kPa. 3.3.6 Melting point The melting point of the product is -77,7 C at 101,3 kPa. 3.3.7 Specific heat The specific heat of the product is 4,61 kJ/(kg K) at 0 C and 4,86 kJ/(kg K) at 40 C. 3.3.8 Viscosity, dynamic The viscosity of the product is 0,254 mPa.s at 33 C and 101,3 kP
28、a. 3.3.9 Critical temperature 132,4 C. 3.3.10 Critical pressure 11 450 kPa. 2) European Inventory of Existing Commercial Chemical Substances. 3) 100 kPa = 1 bar. BS EN 12126:2012EN 12126:2012 (E) 7 3.3.11 Physical hardness Not applicable. 3.4 Chemical properties Ammonia reacts violently with halogen
29、s, acids, acid halides, acid anhydrides and oxidising agents. It reacts with zinc, copper, tin and their alloys. Mixtures of volume fraction of 15 % to 30 % of ammonia with air are explosive. 4 Purity criteria 4.1 General This European Standard specifies the minimum purity requirements for liquefied
30、 ammonia used for the treatment of water intended for human consumption. Limits are given for 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 r
31、elevant authorities. Users of this product should check the national regulations in order to 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 t
32、he product not stated in this product standard. Limits have been given for impurities and chemical 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 quantiti
33、es of impurities, by-products or additives being present, this shall be notified to the user. 4.2 Composition of commercial product Liquefied ammonia shall not contain less than a mass fraction of 99,8 % of NH3. 4.3 Impurities and main by-products The product shall conform to the requirements specif
34、ied in Table 1. Table 1 Impurities Impurity Limit Water max Mass fraction 0,1 % Permanent gases and methane max Volume fraction 0,1 % Oil max 5 mg/kg 4.4 Chemical parameters The chemicals parameters defined in the EU Water Directive (see 1) are not found in liquefied ammonia. Cyanides, pesticides an
35、d polycyclic aromatic hydrocarbons are not by-products of the manufacturing process. BS EN 12126:2012EN 12126:2012 (E) 8 5 Test methods 5.1 Sampling Follow the sampling method according to ISO 7103. 5.2 Analyses 5.2.1 Main product The ammonia concentration is calculated by subtracting the contents o
36、f the main impurities from mass fraction 100 %. 5.2.2 Impurities 5.2.2.1 Water The water content shall be determined in accordance with ISO 7105. 5.2.2.2 Oil content The oil content shall be determined in accordance with ISO 7106. 5.2.3 Permanent gases and methane 5.2.3.1 Principle The method is a g
37、as chromatographic determination of inert gases and methane in liquid ammonia, determined as a volume fraction. The content of trace contaminants is determined by gas chromatography according to an external standard method. Metering from the gas pipette is carried out by means of pressure-controlled
38、 feed via a fixed-volume sampling valve. Liquefied ammonia is evaporated prior to the gas chromatographic test in a special steel gas pipette. 5.2.3.2 Reagents and materials 5.2.3.2.1 Reagents All reagents shall be of a recognised analytical grade and the water used shall conform to the grade 3 spec
39、ified in EN ISO 3696. 5.2.3.2.2 Carrier gas Helium, minimum purity volume fraction 99,9 %. 5.2.3.2.3 Calibration gas mixture of the following composition: hydrogen volume fraction 91 %; nitrogen volume fraction 5 %; methane volume fraction 3 %; BS EN 12126:2012EN 12126:2012 (E) 9 sum of oxygen and a
40、rgon volume fraction 1 %. 5.2.3.2.4 Material for preparation of the column Molecular sieve 13 X of particle size 250 m to 360 m, or any other equivalent suitable material. 5.2.3.3 Apparatus 5.2.3.3.1 Gas chromatographic apparatus. Any suitable gas chromatograph, fitted with a thermal conductivity de
41、tector, may be used. 5.2.3.3.1.1 Characteristics of the gas chromatographic apparatus: Column temperature: typically 40 C isothermal conditions. Detector temperature: typically 130 C. Filament temperature: typically 200 C. 5.2.3.3.1.2 Carrier gas flow rate The carrier gas flow rate shall be approxim
42、ately 25 ml/min. It is usually measured at column outlet and at ambient temperature. 5.2.3.3.2 Injection equipment. Stainless steel gas sample valve with a loop of 2 ml capacity, operating under the following conditions: temperature: ambient to 50 C; pressure: atmospheric. 5.2.3.3.3 Column. 5.2.3.3.
43、3.1 Construction The column may be made of any suitable material that does not react with the test portion, for example stainless steel. Typical dimensions are as follows: a) length: according to the test method used but typically 4 m; b) diameter: internal diameter approximately 3,2 mm; external di
44、ameter approximately 6 mm; c) shape: adapted to the oven geometry. If coiled, the coil diameter shall be at least ten times the outer diameter of the tube. 5.2.3.3.3.2 Packing 5.2.3.3.3.2.1 Composition Molecular sieve (see 5.2.3.2.4). BS EN 12126:2012EN 12126:2012 (E) 10 5.2.3.3.3.2.2 Method of pack
45、ing Use a standardised procedure to give a packed column capable of separating the permanent gas and methane. 5.2.3.3.3.3 Thermal conductivity detector, of such sensitivity that the height of the permanent gas and methane peaks to be measured at the limit of detection is not less than twice the peak
46、-to-noise level. 5.2.3.3.3.4 Recorder The development of the retention time shall be approximately 10 min. 5.2.3.4 Procedure 5.2.3.4.1 Setting up the chromatograph Set up the chromatograph as specified in 5.2.3.2 and 5.2.3.3. 5.2.3.4.2 Determination of the area correction factor Approximately 25 kPa
47、(p) of the calibrating gas is precisely metered into the gas chromatographic system and chromatographied under the conditions specified in 5.2.3.2 and 5.2.3.3. The peak areas are determined and the area correction factors calculated in accordance with 5.2.3.5.1. 5.2.3.4.3 Determination To determine
48、methane and inert gases, approximately 90 kPa (ps) of the gas sample is precisely metered in via a 2 ml sampling valve and chromatographied under the conditions specified in 5.2.3.2 and 5.2.3.3. The peak areas are determined and the volume fraction is calculated in accordance with 5.2.3.5.2. BS EN 1
49、2126:2012EN 12126:2012 (E) 11 5.2.3.4.4 Examination of the chromatogram 5.2.3.4.4.1 Typical chromatogram See Figure 1. Key 1) amplitude 2) retention time in minutes 3) oxygen 4) nitrogen 5) methane Figure 1 Typical chromatogram for liquefied ammonia 5.2.3.4.4.2 Retention time The retention time is approximately 10 min. BS EN 12126:2012EN 12126:2012 (E) 12 5.2.3.5 Calculations 5.2.3.5.1 Calculation of the area correction factors (fi) The area correction factor for oxygen,
