BS 1016-8-1977 Methods for analysis and testing of coal and coke Chlorine in coal and coke《煤和焦炭的分析与试验方法 第8部分 煤与焦炭中的氯》.pdf

1、BRITISH STANDARD BS 1016-8: 1977 Incorporating Amendment Nos. 1 and2 Methods for Analysis and testing of coal and coke Part 8: Chlorine in coal and coke UDC 662.66 +662.74:543.848:546.13BS1016-8:1977 This British Standard, having been prepared under the directionof the Solid Fuel Standards Committee

2、, was published under the authority ofthe Executive Board on 29 April 1977 BSI 08-1999 First published March 1942 First revision September 1959 Second revision April 1977 The following BSI references relate to the work on this standard: Committee references SFC/45 and SFC/45/8 Draft for comment 73/4

3、2189DC ISBN 0 580 09303 4 Cooperating organizations The Solid Fuel Standards Committee, under whose supervision this British Standard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: The organizations marked with an aste

4、risk in the above list, together with the following, were directly represented on the committee entrusted with the preparation of this British Standard: Association of Consulting Engineers Health and Safety Executive British Carbonization Research Association* Heating and Ventilating Contractors Bri

5、tish Cast Iron Research Association Association British Ironfounders Association Institute of British Foundrymen* British Mechanical Engineering Confederation Institute of Fuel Central Electricity Generating Board* Institution of Heating and Ventilating Chamber of Coal Traders Engineers Coke Oven Ma

6、nagers Association* Low Temperature Coal Distillers Association Combustion Engineering Association* of Great Britain Ltd. Council of Ironfoundry Associations National Coal Board* Department of Energy Society of British Gas Industries Domestic Solid Fuel Appliances Approval Solid Fuel Advisory Servic

7、e Scheme Water-tube Boilermakers Association Greater London Council Womens Solid Fuel Council British Coal Exporters Federation Institute of Trading Standards Administration British Gas Corporation London Coal Exporters Association British Steel Corporation Scientific Instruments Manufacturers Cemen

8、t Makers Federation Association of Great Britain Chemical Industries Association Society of Chemical Industry Electricity Supply Industry in England and Solid Smokeless Fuels Federation Wales Independent experts Amendments issued since publication Amd. No. Date of issue Comments 3472 December 1980 6

9、984 May 1992 Indicated by a sideline in the marginBS1016-8:1977 BSI 08-1999 i Contents Page Cooperating organizations Inside front cover Foreword ii 1 Scope 1 2 References 1 3 Definitions 1 4 Sample 1 5 Eschka method 1 6 High temperature method 2 7 Reporting of result 4 8 Precision of the determinat

10、ion 4 Figure 1 Temperature distribution curve in combustion tube for determination of chlorine (high temperature method) 3 Figure 2 Absorption train and furnace for chlorine (high temperature method) 5 Publications referred to Inside back coverBS1016-8:1977 ii BSI 08-1999 Foreword BS 1016 comprises

11、a series of Parts dealing with methods for the analysis and testing of coal and coke. It is gradually being restructured and Parts in the new series have been allocated numbers from 100onwards. The current Parts are as follows, with new Part numbers (which will be given to revisions when they are pu

12、blished) in parentheses where appropriate. Part 1: Total moisture of coal (Part101); Part 2: Total moisture of coke (Part102); Part 6: Ultimate analysis of coal (Part106); Part 7: Ultimate analysis of coke (Part106); Part 8: Chlorine in coal and coke (Part106); Part 9: Phosphorus in coal and coke (P

13、art106); Part 10: Arsenic in coal and coke (Part106); Part 11: Forms of sulphur in coal (Part106); Part 14: Analysis of coal ash and coke ash (Part114); Part 15: Fusibility of coal ash and coke ash (Part113); Part 16: Methods for reporting results (Part100); Part 17: Size analysis of coal (Part109);

14、 Part 18: Size analysis of coke (Part110); Part 20: Determination of Hardgrove grindability index of hard coal (Part112); Part 21: Determination of moisture-holding capacity of hard coal (Part103); Part 104: Proximate analysis; Part 105: Determination of gross calorific value; Part 107: Caking and s

15、welling properties of coal; Part 108: Tests special to coke; Part 111: Determination of abrasion index of coal. The methods given in BS1016 are specified for the analysis of coal or of coke or, in some instances, for the analysis of both coal and coke. It is expected that the methods given in this P

16、art would also be applicable to the determination of chlorine in manufactured smokeless fuels (other than coke) made by a conventional process, although no systematic survey has been made. The revision of Part8 has been undertaken in order to complete the introduction of metric units and to adopt a

17、uniform presentation. No technical changes have been made to the methods; these are technically equivalent to those specified in ISO352 and ISO587. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct

18、application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1to6, an inside back cover and a back cover. This standard has been updated (see copyright date

19、) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS1016-8:1977 BSI 08-1999 1 1 Scope This Part of BS1016 describes two methods of determining the amount of chlorine in coal and coke. 2 References The titles of the publications referr

20、ed to in this standard are listed on the inside back cover. 3 Definitions For the purposes of this Part of BS1016 the following definitions apply. 3.1 coke the solid residue of the distillation of coal at high temperature (above 800 C) 3.2 repeatability the maximum acceptable difference between dupl

21、icate determinations carried out at different times in the same laboratory on the same analysis sample by the same operator using the same apparatus 3.3 reproducibility the maximum acceptable difference between the mean of duplicate determinations carried out in one laboratory and the mean of duplic

22、ate determinations carried out in any other laboratory on representative samples taken from the same gross sample after the last stage of the reduction process 4 Sample The coal or coke used for the determination of chlorine shall be the analysis sample having a top size not greater than 0.2mm (grou

23、nd to pass a2124m test sieve complying with the requirements of BS410), taken and prepared according to BS1017-1 or BS1017-2 as appropriate. The sample shall be thoroughly mixed, preferably by mechanical means, immediately before the determination. 5 Eschka method 5.1 Principle. A known mass of the

24、sample is ignited in intimate contact with Eschka mixture in an oxidizing atmosphere at 675 C, to remove the organic material and to convert all the chlorine to chloride. This is then extracted in nitric acid and determined by a modified Volhard method. 5.2 Special reagents. All reagents, unless oth

25、erwise specified, shall be of analytical reagent quality. Distilled or deionized water complying with the requirements of BS3978 shall be used throughout. 5.2.1 Eschka mixture. A mixture composed of two parts by mass of light magnesium oxide and one part by mass of anhydrous sodium carbonate. 5.2.2

26、Nitric acid, d =1.42. 5.2.3 Silver nitrate solution, 0.025N. 5.2.4 Potassium thiocyanate solution, 0.025N. 5.2.5 Nitrobenzene 5.2.6 Ammonium ferric sulphate indicator. Prepare a saturated solution of ammonium ferric sulphate, (NH 4 ) 2SO 4 .Fe 2 (SO 4 ) 3 .24H 2 O (approximately 124g in 100ml of wat

27、er. Add one drop of nitric acid (see5.2.2) to clear any brown colour. 5.3 Special apparatus. The following special apparatus is required. 5.3.1 Muffle furnace. A muffle furnace capable of maintaining a zone within the range 650 C to700 C. The ventilation shall be such as to give at least four air ch

28、anges per minute at 675 C. NOTEThe number of air changes per minute can be determined by measurement of the air flow in the flue by means of a pitot tube and sensitive manometer 1) . 5.3.2 Crucible. A shallow crucible of glazed porcelain or platinum, approximately 25ml capacity. 5.3.3 Silica plate.

29、A silica plate, 6mm thick, that is an easy sliding fit in the muffle furnace. 5.4 Procedure. Weigh accurately 2.00g to 2.01g of the sample and mix intimately with 3g of the Eschka mixture in the crucible. Level the contents of the crucible and cover with a layer of 2g of the Eschka mixture. Place th

30、e charged crucible on the cold silica plate, insert both into the muffle furnace previously heated to 675 C and maintain at this temperature for 2h. Withdraw the crucible and plate from the furnace and allow to cool. Transfer the charge to a 400ml beaker containing 25ml to30ml of water and wash the

31、crucible thoroughly with about 100ml of hot water, adding the washings to the contents of the beaker. Cover the beaker with a clock glass, add cautiously, with stirring, 20ml of the nitric acid and when the reaction subsides agitate until solution of the soluble material is complete. Filter the solu

32、tion into a conical beaker or flask using a hardened rapid low-ash filter paper 2) . Wash the residue with the minimum amount of hot water until a drop of the washings gives no opalescence with the silver nitrate solution. About four washes will be necessary using 5ml to 10ml of water each time. 1)

33、E Owen, The measurement of air flow, 3rd edn. revised (Chapman and Hall, London), 87. 2) Whatman No.541 is suitable.BS1016-8:1977 2 BSI 08-1999 To the combined flitrate and washings add 20.0ml of the silver nitrate solution and 5ml of the nitrobenzene; shake vigorously for 1min. Add 1ml of the ferri

34、c alum indicator and titrate with the potassium thiocyanate solution until the solution becomes faintly orange-pink in colour. 5.5 Determination of blank. Carry out a blank determination at the same time and under the same conditions as the actual determination but omitting the sample. 5.6 Calculati

35、on of result where 6 High temperature method 6.1 Principle. A known mass of the sample is burned in a stream of oxygen in a tube furnace at1350 C. The chlorine, together with oxides of sulphur formed, is absorbed in neutral hydrogen peroxide, forming hydrochloric acid and sulphuric acid. The solutio

36、n is neutralized with sodium borate and the sodium chloride formed is converted by reaction with mercuryII oxycyanide to sodium hydroxide, which is determined volumetrically. 6.2 Special reagents. All reagents, unless otherwise specified, shall be of analytical reagent quality. Distilled or deionize

37、d water complying with the requirements of BS3978 shall be used throughout. 6.2.1 Sodium borate solution, 0.05N. 6.2.2 Sulphuric acid, 0.025N. 6.2.3 Hydrogen peroxide solution containing 3parts of 100volume H 2O 2and 97parts of water, neutralized with the sodium borate solution (see6.2.1) to the scr

38、eened indicator (see6.2.4). 6.2.4 Screened indicator. Proceed as follows. A) Dissolve 0.125g of methyl red in 100ml of ethanol (95% v/v). B) Dissolve 0.083g of methylene blue in 100ml of ethanol (95% v/v); store in a dark glass bottle. Mix equal volumes of A) and B) immediately before use. 6.2.5 Mer

39、cury II oxycyanide, saturated solution at20 C (approximately4.5g/100ml). Saturate about 100ml of water with mercuryII oxycyanide(3Hg(CN).H g O) by prolonged agitation; filter and neutralize the flitrate with the sulphuric acid, using the screened indicator. Store the solution in a dark bottle; do no

40、t keep longer than 4 days. WARNING. This compound and its solution are toxic and should be handled with great care. 6.2.6 Aluminium oxide, finely divided approximately 0.1mm. 6.2.7 Oxygen 6.2.8 Sodium hydroxide on an inert base, preferably of coarse grading, e.g. 1.7mm to 1.2mm, and preferably of th

41、e self-indicating type. WARNING. Reagents containing asbestos as the base material should not be used. 6.3 Special apparatus. The following special apparatus is required. 6.3.1 Purification train. A tower containing sodium hydroxide on an inert base (see6.2.8) for removing any chlorine compounds fro

42、m the oxygen supply. 6.3.2 Heating unit. An electrically heated furnace designed to carry a tube of 28.5mm outside diameter and to heat it over a length of about125mm to give a temperature of 1350 C at the centre of the hot zone and a temperature-distribution curve similar to that shown inFigure 1.

43、6.3.3 Combustion tube. A tube, 22mm internal diameter and 28.5mm outside diameter by 0.65m long, made of refractory aluminous porcelain that is not permeable to gases at 1400 C 3) . 6.3.4 Combustion boat. A combustion boat of iron-free unglazed porcelain, 70mm long by12.5mm wide by 10mm deep, that d

44、oes not blister, discolour or change in weight on heating at1350 C in oxygen for 3h. m is the mass of the sample taken (ing) V 1 is the volume of 0.025N potassium thiocyanate used in the determination (inml) V 2 is the volume of 0.025N potassium thiocyanate used in the blank (inml) Cl is the percent

45、age of chlorine in the analysis sample. Cl 0.08864 V 2 V 1 () m - = 3) Suitable material is marketed under the trade names Pythagoras, Thermal 525 Ware or Triangle H.BS1016-8:1977 BSI 08-1999 3 6.3.5 Silica pusher. A sealed tube or rod of silica,6mm diameter by approximately 450mm long, flattened at

46、 one end to form a disc of 12mm diameter for pushing the boat into the furnace. The pusher passes loosely through a glass or metal T-piece, one end of which fits into the rubber stopper that closes the inlet end of the combustion tube, the other end being sealed with a rubber sleeve through which th

47、e pusher slides. Oxygen is admitted through the limb of the T-piece. The pusher is marked in millimetres from the disc end for convenience in measuring how far the boat is pushed into the combustion tube. 6.3.6 Nickel-chromium wire. A length of stiff nickel-chromium wire with a hooked end, to extrac

48、t the boat from the furnace on to a refractory tile. 6.3.7 Flowmeter. A flowmeter, capable of measuring a rate of flow of oxygen of up to 300ml/min. 6.3.8 Pressure gauge. A manometer to measure the back pressure on the system, normally5mbar 4) 6.3.9 Silica adaptor. A translucent silica tube,10mm out

49、side diameter by approximately250mm long, terminating at one endin a funnel of 20mm outside diameter. 6.3.10 Absorption vessel. A gas washing tube or bottle with a sintered disc of porosity grade P40 complying with the requirements of BS1752, of such a size that a 90mm seal of liquid is obtained with 100ml of liquid in the vessel (seeFigure 2). 6.3.11 Heat-resistant stopper. A heat-resistant stopper of acrylonitrile for attaching the absorption train to the combust