《BS-6035-1-1981 ISO-5267-1-1979.pdf》由会员分享，可在线阅读，更多相关《BS-6035-1-1981 ISO-5267-1-1979.pdf（12页珍藏版）》请在三一文库上搜索。
1、BRITISH STANDARD BS 6035-1: 1981 ISO 5267-1: 1979 Methods for Determination of the drainability of pulps Part 1: Schopper-Riegler method ISO title: Pulps Determination of drainability Part 1: Schopper-Riegler method UDC 676.017.3 Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 15:24:13 GMT+00
2、:00 2006, Uncontrolled Copy, (c) BSI BS 6035-1:1981 This British Standard, having been prepared under the direction of the Paper Standards Committee, was published under the authority of the Executive Board and comes into effect on 31 December 1980 BSI 12-1999 The following BSI references relate to
3、the work on this standard: Committee reference PAS/11 Draft for comment 78/60850 DC ISBN 0 580 11749 9 Cooperating organizations The Paper Standards Committee, under whose direction this British Standard was prepared, consists of representatives from the following: British Paper and Board Industry F
4、ederation (PIF)* British Printing Industries Federation* Envelope Makers and Manufacturing Stationers Association* HM Customs and Excise Her Majestys Stationery Office* Institute of Trading Standards Administration National Association of Paper Merchants National Economic Development Office Pira (Th
5、e Research Association for the Paper and Board, Printing and Packaging Industries)* Royal Institute of Public Health and Hygiene The organizations marked with an asterisk in the above list, together with the following, were directly represented on the Technical Committee entrusted with the preparati
6、on of this British Standard: British Fibreboard Packaging Association British Wood Pulp Association Chemical Industries Association Man-made Fibres Association Ministry of Agriculture, Fisheries and Food Ministry of Defence Post Office Society of British Printing Ink Manufacturers University of Manc
7、hester, Institute of Science and Technology Amendments issued since publication Amd. No.Date of issueComments Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 15:24:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 6035-1:1981 BSI 12-1999i Contents Page Cooperating organizationsInside front cov
8、er National forewordii 1Scope1 2Field of application1 3Reference1 4Principle1 5Definition1 6Apparatus1 7Preparation of sample1 8Procedure1 9Expression of results2 10Test report2 Annex A The Schopper-Riegler apparatus3 Annex B Maintenance of the Schopper-Riegler apparatus3 Figure 1 Schopper-Riegler a
9、pparatus5 Figure 2 Sealing cone6 Figure 3 Bottom orifice6 Figure 4 Spreader cone6 Publications referred toInside back cover Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 15:24:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 6035-1:1981 ii BSI 12-1999 National foreword This British Standard
10、 has been prepared under the direction of the Paper Standards Committee. It is identical with ISO 5267-1 “Pulps Determination of drainability Part 1: Schopper-Riegler method”, which was developed by Technical Committee ISO/TC 6, Paper, board and pulps, and was published by the International Organiza
11、tion for Standardization (ISO). It is intended to publish a second Part of this British Standard entitled “Canadian Standard freeness number method”, which will be identical with ISO 5267-2 when that International Standard is published. Terminology and conventions. The text of the International Stan
12、dard has been approved as suitable for publication, without deviation, as a British Standard. Some terminology and certain conventions are not identical with those used in British Standards; attention is especially drawn to the following. The comma has been used throughout as a decimal marker. In Br
13、itish Standards it is current practice to use a full point on the baseline as the decimal marker. Wherever the words “International Standard” appear, referring to this standard, they should be read as “British Standard”. A British Standard does not purport to include all the necessary provisions of
14、a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-reference International StandardCorresponding British Standard ISO 4119:1978BS 5878:1980 Method for determination
15、of stock concentration of pulps (rapid method) (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 6, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated.
16、 This will be indicated in the amendment table on the inside front cover. Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 15:24:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 6035-1:1981 BSI 12-19991 1 Scope This International Standard specifies a method for determination of the drainabilit
17、y of a pulp suspension in water in terms of the Schopper-Riegler (SR) number. The Schopper-Riegler test is designed to provide a measure of the rate at which a dilute suspension of pulp may be dewatered. It has been shown that the drainability is related to the surface conditions and swelling of the
18、 fibres, and constitutes a useful index of the amount of mechanical treatment to which the pulp has been subjected. Results of this test do not necessarily correlate with the drainage behaviour of a pulp material on a commercial paper machine. A method for the determination of drainability in terms
19、of the “Canadian Standard” freeness number is specified in ISO 5267-2.1) 2 Field of application In principle, this method is applicable to all kinds of pulp in aqueous suspension. NOTEHowever, in practice, the Schopper-Riegler test provides acceptable results only if a sufficiently dense mat of fibr
20、es is formed on the wire screen. For this reason, the test is not recommended for some extremely short-fibred pulps, such as those from well-beaten hard-woods, as most of the fibres will pass through the wire screen, resulting in anomalous reduction in the SR number. The most reliable results are ob
21、tained within the range of 10 to 90 SR number. 3 Reference ISO 4119, Pulps Determination of stock concentration. 4 Principle Draining, through a fibre mat formed during the test on a wire screen, of a given volume of pulp in aqueous suspension into a funnel provided with a bottom and a side orifice.
22、 Collection of the discharge from the side orifice in a measuring cylinder, graduated in Schopper-Riegler numbers. 5 Definition For the purposes of this International Standard, the following definition applies: Schopper-Riegler number scale a scale on which a discharge of 1 000 ml corresponds to a S
23、R number of zero and zero discharge to a SR number of 100 6 Apparatus Ordinary laboratory apparatus and 6.1 Schopper-Riegler apparatus, as described in Annex A. Instructions for maintenance of the apparatus are given in Annex B. 7 Preparation of sample Take a sample of aqueous suspension of disinteg
24、rated pulp. If the concentration is not known exactly, dilute the suspension to approximate 0,22 % (m/m) with distilled or deionized water (see note 3), and determine the stock concentration in accordance with ISO 4119. Then dilute the suspension to a stock concentration of 0,2 0,002 % (m/m) and adj
25、ust the temperature to 20,0 0,5 C (see note 4). Throughout the preparation of the sample, take care to avoid the formation of air bubbles in the suspension. NOTE 1With time, an aqueous pulp suspension, withdrawn from the stock preparation system or laboratory pulp evaluation equipment, can undergo a
26、 change in Schopper-Riegler number. To avoid the effect of this reversion phenomenon, pulp suspensions subjected to testing more than 30 min after sampling should first be treated in the disintegration apparatus for 6 000 revolutions of the propellor, at or near the stock concentration specified for
27、 the SR test. NOTE 2The test result is sensitive to the quantity of pulp fines, or “crill”, in the suspension. Thickened pulp samples may lose some of this fibre fraction. To avoid such losses during the course of thickening, the filtrate should be recirculated through the pulp pad until the filtrat
28、e is clear, and the pulp redispersed by disintegrating as described in note 1. This procedure should be used to concentrate dilute pulp suspension to the Part II stock concentration required for the Schopper-Riegler test. NOTE 3As the drainage of a pulp suspension is affected considerably by dissolv
29、ed solids and the pH of the water, either distilled or deionized water of equivalent quality should be used throughout the test. NOTE 4Where necessary for climatic reasons, a temperature of 25 5 C may be applied, provided that this is noted in the test report. In any case, during the test the basic
30、temperature chosen should be kept constant within 0,5 C. 8 Procedure Clean the funnel and drainage chamber of the Schopper-Riegler apparatus (6.1) thoroughly and finally rinse with water. Place the drainage chamber in the seat of the funnel. Adjust the temperature of the apparatus by rinsing it with
31、 water at 20,0 0,5 C (see note 4 in clause 7). Place the sealing cone in the closed position and set the SR measuring cylinder beneath the side orifice. 1) At present at the stage of draft. Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 15:24:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS
32、6035-1:1981 2 BSI 12-1999 Whilst stirring, transfer 1 000 5 ml of homogeneous pulp suspension to a clean measuring cylinder. Mix the sample by closing the top of the cylinder by hand and turning it end-over-end for two cycles. Avoid introducing air into the stock at this stage. Pour the sample rapid
33、ly but smoothly into the drainage chamber. Direct the stream against the shaft and the wings of the sealing cone to avoid a vortex. Raise the sealing cone 5 s after all the pulp suspension has been added. Read the SR number to the nearest unit when no more water drips from the side orifice. 9 Expres
34、sion of results Carry out two determinations on each sample. Duplicate determinations which differ by more than 4 % shall be repeated. 10 Test report The test report shall give the following particulars: a) reference to this International Standard; b) all indications necessary for complete identific
35、ation of the sample; c) the test temperature; d) the results, expressed in Schopper-Riegler numbers; e) any unusual features observed in the course of the test; f) any operations not specified in this International Standard or in the International Standard to which reference is made or regarded as o
36、ptional, which might have affected the results. Licensed Copy: sheffieldun sheffieldun, na, Wed Dec 06 15:24:13 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS 6035-1:1981 BSI 12-19993 Annex A The Schopper-Riegler apparatus A.1 The Schopper-Riegler apparatus (see Figure 1) comprises a drainage chamber
37、 equipped with a wire screen, a sealing cone, and a funnel mounted on a suitable support. All parts are made of non-corrodible material. The drainage chamber is a cylinder having an internal diameter of 137 mm; at its lower end is a 45 tapered section, followed by a cylindrical part having a diamete
38、r of 112,9 0,1 mm (cross-sectional area 100 cm2). The tapering section forms a seat for the sealing cone. The wire screen is of phosphor bronze, and fits tightly into the cylinder 25 mm below the taper. It is plane, is mounted perpendicular to the cylinder axis, and has a thickness of 0,40 mm. It ha
39、s 24 weft and 32 warp meshes per 10 mm, the weft strands having a thickness of 0,17 mm and the warp strands 0,16 mm. A.2 The sealing cone (see Figure 1, part B, and Figure 2) has an outside diameter of 120 mm; its tapered surface is at 55 to the vertical. The sealing cone is fitted to a vertical sha
40、ft having outside diameter of 20 mm. A vent having a diameter of 10 mm runs axially through the sealing cone and the shaft, to permit the passage of air when the sealing cone is raised. The shaft is provided with two wings placed diametrically and vertically, to prevent vortices in the pulp suspensi
41、on. The seal consists of a rubber ring of 30 Shore hardness. The sealing cone shall be raised at a constant rate of 100 10 mm/s. A.3 The funnel (see Figure 1, part D) has an upper conical section which provides a seating for the drainage chamber, and enables the sealing cone to be centred accurately
42、 in the chamber. This conical section is followed by a cylindrical section, having a cross-sectional area of 100 cm2 and a height of 35 mm. Near the top of this section is a vent for equalization of the air pressure. The cylindrical section has three grooves, which determine the location of the spre
43、ader cone. The lower part of the funnel is conical having a cone angle of 40,0, it terminates in a separate bottom orifice having the dimensions specified in Figure 3. The diameter of the cylindrical section of the bottom orifice is so chosen that 1 000 ml of water at 20,0 0,5 C poured into the funn
44、el drains out in 149 1 s. This necessitates a diameter of about 2,32 mm (see Annex B). A.4 The side orifice (see Figure 4) has an internal diameter of 16,0 0,1 mm and an outside diameter of 19,0 0,1 mm. It penetrates the funnel at an angle of 49,0 to the vertical. The upper end of the side orifice i
45、s cut at 12,0 to the central axis of the funnel, and the overflow edge is as close as possible to the centre of the funnel, in this position, the volume between the lower edge of the bottom orifice and the overflow edge of the side orifice is 7,5 to 8,0 ml. The level of the overflow edge is adjustab
46、le. A detachable spreader cone is placed in the funnel to prevent splash from entering the side orifice. One of the supporting legs of the spreader cone is set diametrically to the side orifice. A.5 The measuring cylinder is so graduated that it provides a direct reading of the Schopper-Riegler numb
47、er, with a volume of 1 000 ml corresponding to zero SR number, and a volume of zero ml to 100 SR units. The distance between two graduations shall be at least 1,5 mm, corresponding to a volume of 10 ml equal to one SR number. Annex B Maintenance of the Schopper-Riegler apparatus B.1 The SR apparatus
48、 shall be mounted in a vibration-free environment, and carefully levelled by a machinists level placed on the open top of the rate-measuring funnel, in position in the bracket. Rotation of the level on the funnel will indicate when the instrument is mounted in a true level position. B.2 The SR appar
49、atus shall be checked regularly as follows: B.2.1 Check with a feeler gauge that the gasket on the wire screen makes a tight fit against the screen, so that the effective drainage area is 100 cm2. B.2.2 Check that the sealing ring is in good condition. Pour water into the drainage chamber to check that the sealing cone fits tightly. B.2.3 Check that the apparatus is clean and free from deposits of pitch. If necessary, clean with soap and rinse thoroughly with water. Special attention should be paid to the wire screen. To