1、BRITISH STANDARD BS 1016-106.1.2: 1996 ISO 625:1996 (Incorporating Corrigendum 1:1996) Methods for Analysis and testing of coal and coke Part 106: Ultimate analysis of coal and coke Section 106.1 Determination of carbon and hydrogen content Subsection 106.1.2 Liebig method ICS 75.160.10BS1016-106.1.
2、2:1996 This British Standard, having been prepared under the direction of the Sector Board for Materials and Chemicals, was published under the authority ofthe Standards Board and comesinto effect on 15 November 1996 BSI 11-1998 The following BSI references relate to the work on this standard: Commi
3、ttee reference SFI/3 Draft for comment 93/508889 DC ISBN 0 580 26493 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee SFI/3, Analysis and testing of coal and coke, upon which the following bodies were represented: Britis
4、h Cement Association British Coal Corporation British Iron and Steel Producers Association Electricity Association GAMBICA (BEAMA Ltd.) Power Generation Contractors Association (PGCA (BEAMA Ltd.) Amendments issued since publication Amd. No. Date CommentsBS 1016-106.1.2:1996 BSI 11-1998 i Contents Pa
5、ge Committees responsible Inside front cover National foreword ii Introduction 1 1 Scope 1 2 Normative references 1 3 Principle 1 4 Reagents and materials 1 5 Apparatus 2 6 Preparation of the apparatus 5 7 Preparation of test sample 8 8 Procedure 8 9 Blank test 8 10 Expression of results 8 11 Precis
6、ion 9 12 Test report 9 Annex A (informative) Deviation of factors used in calculations in clause 10 10 Figure 1 Midvale tube 3 Figure 2 Guard tube 4 Figure 3 Absorption train 5 Figure 4 Arrangement of the spacing in the combustion tube 7 Table 1 9 Table A.1 10 List of references Inside back coverBS1
7、016-106.1.2:1996 ii BSI 11-1998 National foreword This British Standard has been prepared by Technical Committee SFI/3 and is identical to ISO625:1996 Solid mineral fuels Determination of carbon and hydrogen Liebig method, incorporating Corrigendum 1:1996, published by the International Organization
8、 for Standardization (ISO) and in the preparation of which the UK played a full part. BS1016-106 will form a revision of Parts 6 to 11 of BS1016. This method is an alternative to Subsection 106.1.1 High temperature combustion method, together with which it supersedes the following: in BS1016-6:1977,
9、 clauses 5 and 6 and that part of clause 11 relating to carbon and hydrogen; in BS1016-7:1977, clauses 5 and 6 and that part of clause 10 relating to carbon and hydrogen. BS1016-106 is part of a rationalized and restructured BS1016. The Parts numbered from 1 to 21 are gradually being withdrawn and r
10、eplaced by Parts in the new series. The full list of Parts in the new series, together with corresponding numbering of the old series and related International Standards is given in BS1016 Analysis and testing of coal and coke Part100:1994 General introduction and methods for reporting results. Cros
11、s-references. The Technical Committee has reviewed the provisions of ISO1015:1992, ISO5068:1983 and ISO5069-2:1983 to which normative reference is made in the text, and has decided that they are acceptable for use in conjunction with this standard. British Standards related to ISO331:1983, ISO687:19
12、74, ISO925:1980, ISO1170:1977, ISO1988:1975 and ISO2309:1980 are BS1016: Methods for analysis and testing of coal and coke Part104: Proximate analysis Section104.1:1991 Determination of the moisture content of the general analysis sample of coal, Section104.2:1991 Determination of the moisture conte
13、nt of the general analysis sample of coke, Part6:1991 Ultimate analysis of coal, Part100:1994 General introduction and methods for reporting results, BS1017: Sampling of coal and coke Part1:1989 Methods for sampling of coal and Part2:1994 Methods for sampling of coke. ISO1988 and ISO2309 are being r
14、evised and will be published in eight Parts, and it is intended to implement these Parts as identical British Standards superseding BS1017. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct applicat
15、ion. 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, pages i and ii, pages1 to 10, an inside back cover and a back cover. This standard has been updated (see copyright date) a
16、nd may have had amendments incorporated. This will be indicated in the amendment table on theinside front cover.BS 1016-106.1.2:1996 BSI 11-1998 1 Introduction An alternative method to that specified in this International Standard is given in ISO609:1996, Solid mineral fuels Determination of carbon
17、and hydrogen High temperature combustion method. 1 Scope This International Standard specifies a method of determining the total carbon and the total hydrogen in hard coal, brown coal and lignite, and coke, by the Liebig method. The results include the carbon in the carbonates and the hydrogen combi
18、ned in the moisture and in the water of constitution of silicates. A determination of moisture is carried out at the same time, and an appropriate correction is applied to the hydrogen value obtained by combustion. A determination of carbon dioxide may also be made and the total carbon value correct
19、ed for the presence of mineral carbonates. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revisi
20、on, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 331:1983, Coal Determinati
21、on of moisture in the analysis sample Direct gravimetric method. ISO 687:1974, Coke Determination of moisture in the analysis sample. ISO 925:1980, Solid mineral fuels Determination of carbon dioxide content Gravimetric method. ISO 1015:1992, Brown coals and lignites Determination of moisture conten
22、t Direct volumetric method. ISO 1170:1977, Coal and coke Calculation of analyses to different bases. ISO 1988:1975, Hard coal Sampling. ISO 2309:1980, Coke Sampling. ISO 5068:1983, Brown coals and lignites Determination of moisture content Indirect gravimetric method. ISO 5069-2:1983, Brown coals an
23、d lignites Principles of sampling Part 2: Sample preparation for determination of moisture content and for general analysis. 3 Principle A known mass of coal or coke is burnt in a current of oxygen in a tube impervious to gases, the products of the incomplete combustion being further burnt over copp
24、er oxide; all the hydrogen is converted to water and all the carbon to carbon dioxide. These products are absorbed by suitable reagents and determined gravimetrically. Oxides of sulfur are retained by lead chromate, chlorine by a silver gauze roll and oxides of nitrogen by granular manganese dioxide
25、. 4 Reagents and materials WARNING Care should be exercised when handling reagents, many of which are toxic. During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and only distilled water or water of equivalent purity. 4.1 Magnesium perchlorate, anhydrous, le
26、ss than1,2mm in size and preferably within the size range 1,2mm to 0,7mm. WARNING Due regard must be taken of local regulations when disposing of exhausted magnesium perchlorate. Regeneration of magnesium perchlorate must not be attempted, owing to the risk of explosion. 4.2 Sodium hydroxide on an i
27、nert base, preferably of a coarse grading, for example 3,0mm to 1,5mm, but not finer than the grading 1,2mm to0,7mm, and preferably of the self-indicating type. 4.3 Manganese dioxide, granular, 1,2mm to0,7mm. Manganese dioxide in the granular form and the size required can be prepared as follows. Di
28、ssolve manganese sulfate in water and boil the solution. Make the solution alkaline with ammonium hydroxide and add solid ammonium persulfate, in small portions, to the boiling solution until precipitation is complete. Filter through a hardened fast-filter paper, wash with water by decantation, then
29、 with dilute sulfuric acid and finally with water until acid-free. Transfer the moist precipitate to a mortar and place in an oven until most of the water has evaporated, but the powder is still damp. Press the mass into a cake with a pestle, using firm pressure. Complete the drying, break up the ca
30、ke cautiously and sieve to separate the1,2mm to 0,7mm size. 4.4 Copper gauze, of mesh approximately 1mm and10mm wide. 4.5 Copper oxide, wire form, chopped to particles approximately 3mm long with a diameter of approximately 0,2mm.BS 1016-106.1.2:1996 2 BSI 11-1998 4.6 Lead chromate, fused, size rang
31、e 2,4mm to1,2mm. 4.7 Pure silver gauze, of mesh approximately1mm, made of wire approximately0,3mm in diameter. 4.8 Oxygen, hydrogen-free, preferably prepared from liquid air and not by electrolysis. Electrolytically prepared oxygen shall be passed over red-hot copper oxide before use to remove any t
32、race of hydrogen. 4.9 Glass wool. 5 Apparatus 5.1 Analytical balance, capable of weighing to the nearest 0,1mg. 5.2 Purification train, for absorbing water vapour and carbon dioxide from the oxygen used for the combustion. Assemble the train using a series of U-tubes containing the following reagent
33、s in the order stated, in the direction of flow: a) magnesium perchlorate (4.1) for absorbing water; b) sodium hydroxide on an inert base (4.2) for absorbing carbon dioxide; c) magnesium perchlorate for absorbing the water evolved in the reaction between carbon dioxide and sodium hydroxide. The puri
34、fication train shall be large enough to render frequent recharging unnecessary, even with continuous use. 5.3 Combustion assembly 5.3.1 Furnaces. The combustion tube is heated by three furnaces. For the 1,25mm combustion tube described in clause 6, the following approximate lengths are appropriate:
35、a) furnace No. 1 (to heat the boat and its contents to 925C) 250mm; b) furnace No. 2 (to keep the entire copper oxide section of the tube heated to 800C) 500mm; c) furnace No. 3 (to cover the lead chromate and the roll of pure silver gauze and to heat the former to about 500C) 200mm. 5.3.2 Combustio
36、n tube, of fused silica or suitable hard glass. The diameter of the tube shall be 12mm to 15mm. A suitable length is 1,25m. 5.3.3 Combustion boat, of platinum, porcelain or fused silica, approximately 70mm long. 5.4 Absorption train, for absorbing the water and carbon dioxide evolved by the combusti
37、on of the sample. Assemble the train using the following reagents in the order stated, in the direction of flow. a) magnesium perchlorate (4.1) for absorbing the water evolved during the combustion; b) granular manganese dioxide (4.3) for absorbing oxides of nitrogen; c) magnesium perchlorate for ab
38、sorbing the water evolved from the manganese dioxide; d) sodium hydroxide on an inert base (4.2) for absorbing carbon dioxide; e) magnesium perchlorate for absorbing the water produced in the reaction between carbon dioxide and sodium hydroxide. Midvale tubes (Figure 1), which provide a large area o
39、f reaction, are used for all the reagents except manganese dioxide, which is contained in a guard tube (Figure 2), providing a long contact time with minimum mass. A typical absorption train, with details of the packing, is shown in Figure 3. A is the absorber for water, B is a guard-tube absorber f
40、or oxides of nitrogen, and C absorbs any water evolved from the manganese dioxide. Carbon dioxide is absorbed in D, the magnesium perchlorate in the upper portion absorbing any water produced in the reaction between carbon dioxide and sodium hydroxide. A second carbon dioxide absorber, E, should be
41、added as a precautionary measure. Stoppered U-tubes may be used, if preferred, in place of the Midvale tubes. Place glass wool (4.9), previously dried at 105C for1h, above and below the absorbents to prevent the carry-over of dust by the flow of oxygen, and to prevent the cracking of the Midvale tub
42、e by the heat of reaction. If water is condensed in the first absorber, some nitrogen dioxide may dissolve in it and be considered as water. Because of the conversion factor from water to hydrogen, the error in the hydrogen determination thus caused is small, in the order of 0,05% of hydrogen. This
43、can only be avoided by heating the absorption tube to a temperature that is sufficiently high to prevent condensation of water. NOTE 1Oxides of nitrogen formed in the combustion would, in the absence of precautions, be absorbed by the sodium hydroxide and measured as carbon dioxide. The error in the
44、 carbon determination thus caused, in the order of 0,2% of carbon, is substantially avoided by the use of a guard tube (seeFigure 2) in which the gases pass through an annular space to allow oxidation of nitrogen monoxide to nitrogen dioxide which is absorbed by the manganese dioxide.BS 1016-106.1.2
45、:1996 BSI 11-1998 3 Figure 1 Midvale tubeBS 1016-106.1.2:1996 4 BSI 11-1998 Figure 2 Guard tubeBS 1016-106.1.2:1996 BSI 11-1998 5 5.5 Oxygen flow-rate controller, a reducing valve on the oxygen cylinder together with a small needle valve and flowmeter, capable of measuring a flow of up to 100ml/min,
46、 immediately before the purification train, is generally adequate. It may be useful to attach a bubbler device at the exit end of the assembled apparatus to give a visual indication of the rate of flow. 5.6 Heat-resistant stopper (acrylonitrile or chloroprene) for connecting the absorption train to
47、the combustion tube. 5.7 Copper gauze roll, for constraining the reagents in the appropriate sections of the combustion tube(5.3.2). Roll the copper gauze into rolls 10mm long and of sufficient diameter to ensure a close fit in the combustion tube. 5.8 Copper gauze spiral, through which passes a sto
48、ut copper wire provided with a loop to facilitate removal from the combustion tube (5.3.2). 5.9 Silver gauze roll, for absorbing chlorine. Roll the pure silver gauze (4.7) to form a plug, 100mm long and of sufficient diameter to ensure a close sliding fit in the combustion tube (5.3.2). A stout, pur
49、e silver wire is passed through the centre of the roll to facilitate its removal from the tube. 5.10 Heat-resistant wire, approximately 2,5mm thick and 500mm long, with a bent end to place the boat in the correct position in the combustion tube and to transfer the used boat from the combustion tube onto a rigid refractory sheet. 6 Preparation of the apparatus 6.1 Preparation of the combustion tube For a combustion tube 1,25m long and 12mm to15mm in diameter, the following arrangement of the spacing is su