1、BS EN 1278:2010ICS 13.060.20; 71.100.80NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDChemicals used fortreatment of waterintended for humanconsumption OzoneThis British Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 31
2、 May2010. BSI 2010ISBN 978 0 580 68326 8Amendments/corrigenda issued since publicationDate CommentsBS EN 1278:2010National forewordThis British Standard is the UK implementation of EN 1278:2010. Itsupersedes BS EN 1278:1999 which is withdrawn.The UK participation in its preparation was entrusted to
3、TechnicalCommittee CII/59, Chemicals for drinking water treatment.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application
4、.Compliance with a British Standard cannot confer immunityfrom legal obligations.BS EN 1278:2010EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1278 April 2010 ICS 71.100.80 Supersedes EN 1278:1998English Version Chemicals used for treatment of water intended for human consumption - Ozone Produ
5、its chimiques utiliss pour le traitement de leau destine la consommation humaine - Ozone Produkte zur Aufbereitung von Wasser fr den menschlichen Gebrauch - Ozon This European Standard was approved by CEN on 28 February 2010. CEN members are bound to comply with the CEN/CENELEC Internal Regulations
6、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 application to the CEN Management Centre or to any CEN member. This Europea
7、n 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 has the same status as the official versions. CEN members are the natio
8、nal 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, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerl
9、and 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 by any means reserved worldwide for CEN national Members. Ref. No. EN
10、1278:2010: EBS EN 1278:2010EN 1278:2010 (E) 2 Contents Page Foreword 3 Introduction .4 1 Scope 5 2 Normative references 5 3 Description .5 3.1 Identification .5 3.2 Commercial form .5 3.3 Physical properties 6 3.4 Chemical properties 8 4 Purity criteria 8 4.1 General 8 4.2 Composition of commercial
11、product .8 4.3 Impurities and main by-products .8 4.4 Chemical parameters 9 5 Test methods 9 5.1 Sampling .9 5.2 Analyses .9 6 Labelling - Transportation Storage 11 6.1 Means of delivery 11 6.2 Risk and safety labelling according to the EU Directives . 12 6.3 Transportation regulations and labelling
12、 . 12 6.4 Marking 12 6.5 Stability 12 Annex A (informative) General information on ozone 13 A.1 Origin . 13 A.2 Use . 14 A.3 Operational control methods . 15 Annex B (normative) General rules relating to safety 19 B.1 Rules for safe handling and use . 19 B.2 Emergency procedures 19 Bibliography . 20
13、 BS EN 1278:2010EN 1278:2010 (E) 3 Foreword This document (EN 1278:2010) 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
14、or by endorsement, at the latest by October 2010, and conflicting national standards shall be withdrawn at the latest by October 2010. 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 responsibl
15、e for identifying any or all such patent rights. This document supersedes EN 1278:1998. According 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
16、 Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Differences between this edition and EN 1278:1
17、998 are editorial to harmonize the text with other standards in this series. BS EN 1278:2010EN 1278:2010 (E) 4 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 inf
18、ormation as to 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 remai
19、n in force. NOTE Conformity with the 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 is subject to regulation or control by National Authorities. BS EN 1278:2010EN 1278:201
20、0 (E) 5 1 Scope This European Standard is applicable to ozone used for treatment of water intended for human consumption. It describes the characteristics of ozone and specifies a test method for determining the ozone concentration in other gases. 2 Normative references The following referenced docu
21、ments are indispensable for the application of this document. 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, Water for analytical laboratory use Specification and test method
22、 (ISO 3696:1987) 3 Description 3.1 Identification 3.1.1 chemical name ozone 3.1.2 synonym or common name none (has sometimes been called improperly “allotropic oxygen“) 3.1.3 relative molecular mass 48 3.1.4 empirical formula O3 3.1.5 chemical formula O33.1.6 CAS Registry Number 1)10028-15-6 3.1.7 E
23、INECS reference 2) Not applicable 3.2 Commercial form Ozone is generated on or near the site of use. 1) Chemical Abstracts Service Registry Number 2) European Inventory of Existing Commercial Chemical Substances BS EN 1278:2010EN 1278:2010 (E) 6 3.3 Physical properties 3.3.1 Appearance Bluish gas, t
24、he liquid is dark blue. NOTE A weak absorption in the visual range between 435 nm and 475 nm. 3.3.2 Density Gas : 2,144 kg/m3at NTP (Normal Temperature Pressure, 273 K and 101,3 kPa); Liquid : 1,574 g/cm3at - 183 C; Solid : 1,728 g/cm3. 3.3.3 The gas-liquid partition coefficient In pure water, the p
25、artition coefficient values (S) expressed in grams per cubic meter water per (grams per cubic meter) gas at 101,3 kPa are given in table 1. Table 1 The gas-liquid partition coefficient between water and gas phase Temperature of water C Solubility S, in gmHOg m gas/3230 0,645 0,510 0,39 15 0,3120 0,2
26、425 0,19 30 0,1535 0,12NOTE 1 Recent surveys of literature data are given in Bibliography. See 2, 3 and 4. NOTE 2 S is a ratio, not an absolute concentration. 3.3.4 Vapour pressure The vapour pressure of ozone depending on temperature is given in Table 2. BS EN 1278:2010EN 1278:2010 (E) 7 Table 2 Va
27、pour pressure Temperature Vapour pressure C kPa- 183 0,0147 - 180 0,028 - 170 0,188 - 160 0,897 - 150 3,306 - 140 9,892 - 130 25,331 - 120 56,928 - 110 115,322 - 100 2 139,079 3.3.5 Boiling point at 100 kPa 3) - 112 C. NOTE : Vaporization heat : 681 kJ/m3at NTP. 3.3.6 Melting point - 196 C. 3.3.7 Sp
28、ecific heat (liquid) Not applicable. 3.3.8 Viscosity (dynamic) 0,004 2 Pa.s at 195 C; 0,0015 5 Pa.s at 183 C. 3.3.9 Critical temperature - 12,1 C. 3.3.10 Critical pressure 5 460 kPa. 3.3.11 Physical hardness Not applicable. 3) 100 kPa = 1 bar BS EN 1278:2010EN 1278:2010 (E) 8 3.4 Chemical properties
29、 Ozone is a powerful oxidant. The standard redox potentials (25 C) are: (EoH-values in volts): O3+ 2H+ 2e- O2+ H2O EoH= 2,07 V (1) O3+ H2O + 2e- O2+ 2OH-EoH= 1,24 V (2) OH + H+ e- H2O EoH= 2,42 V(calculated value) (3) If the pH increases by one unit, the EH -values shall decrease by 30 mV per electr
30、on transferred. At 100 kPa and 25 C and pH = 7 the EH-values, versus the normal hydrogen electrode, become: O3(1) = 1,66 V; O3(2) = 0,82 V; OH(3) = 2,21V. In water treatment most of the direct reactions of ozone are dipolar cyclo-additions and electrophilic substitution reactions. Moreover ozone, in
31、 water, can generate radicals such as OH : (O3 + H2O 2 OH + O2). The OH radical is a strong general oxidant. 4 Purity criteria 4.1 General This European Standard specifies the minimum purity requirements for Ozone used for the treatment of water intended for human consumption. Limits are given for i
32、mpurities 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. NOTE Users of this product should check the national regulations in order
33、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 the product not stated in this product standard. Limits have been given for impurities and
34、chemicals 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 lead to significant quantities of impurities, by-products or additives being present, this shall be notified to the us
35、er. 4.2 Composition of commercial product Ozone is obtainable in air, oxygen or air enriched in oxygen. Typical concentrations obtainable in air are in the range of 15 g/m3to 45 g/m3(NTP) and, in oxygen 40 g/m3to 200 g/m3(NTP). The concentration (in grams per cubic metre NTP) at the nominal operatin
36、g condition of the generators shall be specified in the tendering documents. 4.3 Impurities and main by-products See A.3.2. BS EN 1278:2010EN 1278:2010 (E) 9 4.4 Chemical parameters NOTE For the purpose of this standard “chemical parameters“ are those defined in the 98/83/EC: Council Directive of 3
37、November 1998 on the quality of water intended for human consumption. (see 1). None of the chemical parameters according to the directive 98/83/EC are found in the gaseous ozone phase. Pesticides and polycyclic aromatic hydrocarbons are not by-products of the ozone manufacturing processes. 5 Test me
38、thods 5.1 Sampling Ozone generation is usually based on a continuous process gas flow mode positive pressure. Sampling of a volume is to be controlled with a totalizing volumetric flow metre, the volumes being expressed at Normal Temperature and Pressure (NTP). In continuous monitoring methods the g
39、as exit shall be open to ambient air or the gas pressure shall be controlled and the results corrected for effects of pressure. Sampling lines shall be in stainless steel (see table A.1) or in polyfluorocarbone material resistant to ozone. The transfer of the gas from the sampling point to the analy
40、zer shall be kept shorter than 1 min. Expression of concentrations : concentration of ozone in a gas in g/m3(NTP), or kg/m3(NTP), and for traces in cm3/m3(equivalent to ppm as volume fraction). NOTE 1 1 g/m3(NTP) equals 6104,466 (volume fraction) and 0,069 9 % (mass fraction) in oxygen or 0,077 3 %
41、(mass fraction) in air. NOTE 2 At conventional concentrations of about 20 g/m3(NTP), the effect of difference in gas densities between ozone and oxygen-nitrogen is negligible. This is not the case when higher ozone concentrations are generated i.e. in oxygen. 5.2 Analyses 5.2.1 General The present m
42、ethod concerns the determination of ozone in air, oxygen or other process gases. The method is directly applicable for ozone concentrations in the range of 1 g/m3to 200 g/m3(NTP). 5.2.2 Principle Direct iodometric titration. 5.2.3 Reagents All reagents shall be of a recognized analytical grade and t
43、he water used shall conform to grade 2 in accordance with EN ISO 3696. 5.2.3.1 Potassium iodide (KI) buffered solution. Potassium iodide (KI) solution at 20 g/l with sodium hydrogen phoshate (Na2HPO4.2 H2O) solution at 7,3 g/l and potassium dihydrogen phosphate (KH2PO4) solution at 3,5 g/l. 5.2.3.2
44、Sodium thiosulfate : standard volumetric, solution c(Na2S2O3) = 0,1 mol/l. BS EN 1278:2010EN 1278:2010 (E) 10 5.2.3.3 Sulfuric acid, solution at 9 mol/l.5.2.3.4 Potassium iodate (KIO3) powdered. 5.2.3.5 Potassium iodide (KI) crystalline. 5.2.3.6 Hydrochloric acid standard volumetric solution c(HCl)
45、= 0,1 mol/l or sulfuric acid c(H2SO4) =0,05 mol/l.5.2.3.7 Zinc iodide (ZnI2)-starch indicator. Disperse 4 g starch into a small quantity of water. Add the dispersion to a solution of 20 g zinc chloride (ZnCl2) in 100 ml water. The solution is boiled until the volume has been reduced to 100 ml and fi
46、nally diluted to 1 l while adding 2 g of ZnI2. 5.2.3.8 Standardization of sodium thiosulfate: 5.2.3.8.1 Reactions 5 KI + 5 H+ 5 HI + 5 K+ (4) KIO3+ H+ HIO3+ K+ (5) HIO3+ 5 HI 3 I2+ 3 H2O (6) 3 I2+ 6 S2O32- 6 I-+ 3 S4O62- (7)5.2.3.8.2 Determination Add 0,05 g of potassium iodate (5.2.3.4), 0,5 g of p
47、otassium iodide (5.2.3.5) into 50 ml water and a further 50 ml water in a conical flask. After mixing, add 10 ml standard volumetric solution acid (5.2.3.6). Titrate the liberated iodine immediately with the sodium thiosulfate solution (5.2.3.2). 5.2.3.8.3 Calculation The concentration, ct, expresse
48、d in moles per litre, of the sodium thiosulfate solution is given by: ccVVtat=(8) where: cais the concentration ,in moles per litre, of the acid (5.2.3.6); V is the volume, in millilitres, of the acid (5.2.3.6); Vtis the volume, in millilitres, of the sodium thiosulfate solution used. 5.2.4 Apparatu
49、s Ordinary laboratory apparatus. 5.2.5 Procedure 5.2.5.1 Add the solution of potassium iodide (200 ml) to a standard gas washing vessel to give a depth of liquid of 10 cm to 15 cm. The use of fritted gas bubblers is not recommended. BS EN 1278:2010EN 1278:2010 (E) 11 5.2.5.2 Connect a second identical flask in series as a guard to check the ozone transfer and reaction. 5.2.5.3 For ozone produced with air, bubble the process gas containing ozone at a flow rate of about 1 l/min until a total expected qua
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