BS-ISO-15360-1-2000.pdf

| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS ISO 15360-1:2000 ICS 85.040 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Recycled pulps Ð Estimation of stickies and plastics Ð Part 1: Visual method Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI This British Standard, having been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 July 2001 BSI 07-2001 ISBN 0 580 36955 2 BS ISO 15360-1:2000 Amendments issued since publication Amd. No.DateComments National foreword This British Standard reproduces verbatim ISO 15360-1:2000 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee PAI/11, Test methods for paper, board and pulp, which has the responsibility to: Ð aid enquirers to understand the text; Ð present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; Ð monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled ªInternational Standards Correspondence Indexº, or by using the ªFindº facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of 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. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to iv, pages 1 to 10, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Reference number ISO 15360-1:2000(E) INTERNATIONAL STANDARD ISO 15360-1 First edition 2000-04-01 Recycled pulps Estimation of Stickies and Plastics Part 1: Visual method Pâtes recyclées Estimation des matières collantes et des matières plastiques Partie 1: Méthode visuelle Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 15360-1:2000(E) ii Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 15360-1:2000(E) iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this part of ISO 15360 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. International Standard ISO 15360-1 was prepared by Technical Committee ISO/TC 6,Paper, board and pulps, Subcommittee SC 5,Test methods and quality specifications for pulp. ISO 15360 consists of the following parts, under the general titleRecycled pulps Estimation of Stickies and Plastics: ?Part 1: Visual method ?Part 2: Image analysis method Annexes A and B form a normative part of this part of ISO 15360. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 15360-1:2000(E) iv Introduction The production of pulp from de-inked recovered fibres and from brown or mixed waste grades is increasing in many parts of the world. Many of the recovered papers used in the production of recycled pulps contain adhesives, latex and other materials, which are either intrinsically “tacky“ or can become so under appropriate conditions of temperature, pH and pressure. Residual particles of such materials can cause problems when the pulp is subsequently used in paper manufacture. In addition, recycled pulp feedstock is sometimes derived from material that has been plastics coated and the presence of plastics in the finished pulp can also cause problems, especially in the manufacture of coated papers. Moreover, plastics found in recovered paper may also come from a collection which has not been properly sorted. International Standards exist for the determination of visible dirt and shives in pulp and these could be applied to de-inked pulp. However Stickies and Plastics are often similar to the pulp in colour and, even when large, are difficult to detect by visual inspection. Different techniques have thus to be employed. This part of ISO 15360 is based on a visual identification and count of the Stickies and Plastics. Instrumental techniques are also available for estimating Stickies and Plastics. However, these are less widely used but may be the basis of a future International Standard for Stickies and Plastics in recycled pulps. NOTEDifferent types of laboratory screening equipment, complying with this part of ISO 15360 may be used to isolate the Stickies and Plastics from the cellulose stock. It should be noted that different types of laboratory screening equipment may give different results. Furthermore, screening equipment of the same style fitted with different screens complying with this part of ISO 15360 may also give different results because of the difference in the distribution of slit sizes within the screen. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI INTERNATIONAL STANDARDISO 15360-1:2000(E) 1 Recycled pulps Estimation of Stickies and Plastics Part 1: Visual method 1Scope This part of ISO 15360 specifies a method to estimate Stickies and Plastics in a wide variety of pulps including all recycled grades. It is not intended for the estimation of visible dirt and shives which is covered by the ISO 5350 series, or for visible contraries in recycled pulps, which is covered by ISO 153191. This method will only capture those Stickies and Plastics which are retained on the screen of a given slit size. It should be noted that this will probably not be the total amount of Stickies and Plastics that are actually present in a given pulp sample. 2Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of ISO 15360. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of ISO 15360 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 638,Pulps Determination of dry matter content. ISO 4119,Pulps Determination of stock concentration. ISO 5263,Pulps Laboratory wet disintegration. ISO 5269-1,Pulps Preparation of laboratory sheets for physical testing Part 1: Conventional sheet-former method. ISO 5350-1,Pulps Estimation of dirt and shives Part 1: Inspection of laboratory sheets. ISO 5350-2,Pulps Estimation of dirt and shives Part 2: Inspection of mill sheeted pulp. ISO 7213,Pulps Sampling for testing. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 15360-1:2000(E) 2 3Terms and definitions For the purposes of this part of ISO 15360, the following terms and definitions apply. 3.1 Stickies diverse group of materials that are retained on a laboratory screen (5.2) of given slit aperture (100 µm or 150 µm), and which adhere to objects which they touch; Stickies may adhere objects at ambient temperature or they may adopt adhesive characteristics when subjected to elevated temperature, elevated pressure or change of pH NOTE 1The following is a non-exhaustive list of Stickies: products derived from residues of materials such as inks, tars, hot melts, waxes and multivalent metal ion soaps or different types of pressure-sensitive adhesives. NOTE 2A Stickie particle can be a composite of adhesive material, together with non-adhesive plastics fragments and cellulose fibres. 3.2 Plastics non-adhesive polymers that are retained on a laboratory screen (5.2) of a given slit aperture, but excluding cellulosic materials NOTEThe following is a non-exhaustive list of Plastics: polymeric materials derived from such sources as polyethylene, polypropylene, polyester, UV-cured coatings and polystyrene. 3.3 screen that part of the laboratory screening equipment which separates the Stickies and Plastics from the cellulose fibre 4Principle A sample of pulp in disintegrated form is passed through a laboratory screen of given slit aperture until the filtrate is clear. The material retained on the screen is removed and transferred to a filter paper. The Stickies and Plastics are identified and their total numbers and areas are estimated separately. 5Apparatus and equipment 5.1Disintegrator as specified in ISO 5263. 5.2Laboratory screening equipment, fitted with a screen (3.3) complying with the specification described in annex A. NOTEVarious types of laboratory screening equipment may use different terminology to describe the separating medium (e.g. “slots” instead of “slits”). 5.3Filter paper; a qualitative, medium/fast grade is recommended. 5.4Tweezers. 5.5Illumination device: a suitable light source for the investigation of filter papers containing Stickies and Plastics particles in reflected light. The light shall be strong enough to ensure that all particles having the minimum area agreed upon are visible. 5.6Light table, as specified in ISO 5350-1 and ISO 5350-2. This is needed only when Stickies are estimated at elevated temperature and pressure, see 7.5.3. 5.7Desk-top magnifying glass, magnification ?2 to ?4, or microscope, stereo type, magnification ?10 to ?40 (optional only). Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 15360-1:2000(E) 3 5.8Dissecting needles. 5.9Heated press, capable of applying a load of 690 kPa ? 20 kPa at a constant temperature of 150 ?C ? 10 ?C. 5.10Comparison chart, as shown in annex B. 5.11Blotters, as used for the preparation of laboratory sheets in ISO 5269-1. 5.12Oven, capable of maintaining an air temperature of 105 oC ? 2oC. 6Sampling If the estimation of the Stickies and Plastics is to represent the Stickies and Plastics in a lot of pulp, the number of samples to be tested and their selection shall be in accordance with ISO 7213. If the test is made using another type of sampling, make sure that the test pieces are representative of the sample received. 7Procedure 7.1Temperature All operations described in this clause, with the exception of 7.5.3 (Stickies at elevated temperature), shall be carried out at room temperature (20 oC to 25oC). 7.2Pretreatment of sample Determine the dry matter content as described in ISO 638. Soak air-dried pulp samples for at least 4 h in water (tap water may be used). Wet-lap pulp may be disintegrated immediately (see 5.1). Pulp stock with a consistency of 10 % or less need not be disintegrated. Using the procedure described in ISO 5263, disintegrate a sample of pulp of mass and concentration appropriate to the screening equipment used. (See the second paragraph of 7.2.) The conditions of disintegration shall be reported in clause 10. NOTEThe procedure for visible contraries in recycled pulp (ISO 15319) may be used. This procedure disintegrates 50 g to 60 g oven-dried pulp in 2 700 ml of water, until the stock is just clear of fibre bundles. When necessary, determine the concentration of the stock as described in ISO 4119. 7.3Screening of the disintegrated stock Following the manufacturers instructions for the relevant laboratory screening equipment (5.2), add a portion of the prepared stock to the screen (3.3). Process the stock until the filtrate is clear. It is recommended that initially a total mass of 100 g oven-dried pulp should be processed. It may be necessary to process more or less than 100 g of pulp depending on the content of Stickies and Plastics. 7.4Removal of material retained on the screen Stand the screen vertically in a suitable container and wash the slits first from the underside and then from the top side of the slits, with a fine jet of high pressure cold water. Use an amount of washing water that is just sufficient, as far as possible, to remove all the material retained on the screen. Retain the screen for a subsequent visual re- examination. Licensed Copy: sheffieldun sheffieldun, na, Mon Nov 27 08:27:30 GMT+00:00 2006, Uncontrolled Copy, (c) BSI ISO 15360-1:2000(E) 4 Filter the suspension through the filter paper (5.3) ensuring a uniform distribution of Stickies and Plastics on the filter paper. The number of filter papers used is determined by the amount of material retained on the screen. NOTESome commercial laboratory screening equipment transfers the material from the screen to the filter paper automatically. When all the suspension has been filtered, re-examine the screen. Any remaining particles which might be Stickies or Plastics should be removed from the screen with the aid of a pair of tweezers (5.4) and placed on one of the filter papers. Place all the filter papers on separate blotters (5.11) and dry at 105 °C for 1 h in an oven (5.12). 7.5Examination of the material retained on the screen Examine the filter paper(s) in reflected light by eye to identify the types of particles present. Record the number of particl