GB/T 10740-2026Pulps - Determination of dirt and shives (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting.

This document replaces GB/T 10740-2002 "Determination of Pulp Dust and Fiber Bundles". Compared with GB/T 10740-2002, except for the structure...

Aside from adjustments and editorial changes, the main technical changes are as follows.

a) The scope has been changed (see Chapter 1, Chapter 1 of the 2002 edition);

b) Added terms and definitions for pulp board, laboratory paper sheet, specimen, and equivalent black area (see 3.1, 3.2, 3.3, and 3.7), and revised miscellaneous...

Terms and definitions for matter and fiber bundles (see 3.4 and 3.6, 3.1 and 3.3 in the 2002 edition);

c) The requirements for the equipment decomposer and sheet former in laboratory paper preparation have been changed (see 4.2.3.2 and 4.2.3.3, 2002 edition).

5.3.1 and 5.3.2);

d) The sample pretreatment requirements have been changed (see 4.3.2, 6.1.3 of the 2002 edition);

e) The method for determining the oven-dry content has been changed (see 4.4.1 and 5.4.1, 7.1.2 and 7.2.1 in the 2002 edition);

f) The logarithm of the average area in the impurity area groupings has been changed (see Table 2, Table 2 in the 2002 edition);

g) Precision data has been added (see 4.5.3 and 5.5.3);

h) The total sample mass requirement for slurry plate testing has been removed (see 6.2.1 in the 2002 edition);

i) Two new methods have been added. Method 3, the visual method of equivalent black area (EBA) of reflected light (see Chapter 6), and Method 4, the equivalent black area (EBA) of reflected light.

Instrumental method (see Chapter 7);

j) Added EBA standard dust comparison chart, calculation of equivalent black area (EBA), standard plate and instrument detection steps (transmitted light experiment).

(See Appendix C, Appendix D, Appendix E and Appendix F for the chamber paper method and the transmission light plate method).

This document is modified to adopt ISO 5350-1:2006 "Determination of pulp dust and fiber bundles - Part 1: Transmitted light - Laboratory paper".

The standards are. ISO 5350-2:2006 "Determination of dust and fiber bundles in pulp - Part 2: Transmission plate method" and ISO 5350-3:2007 "Paper".

Determination of pulp dust and fiber bundles - Part 3: Visual method of equivalent black area (EBA) of reflected light and ISO 5350-4:2006 "Pulp dust" "Determination of Angstrom and Fiber Bundles, Part 4: Instrumental Method of Equivalent Black Area (EBA) of Reflected Light".

Compared with ISO 5350-1:2006, ISO 5350-2:2006, ISO 5350-3:2007 and ISO 5350-4:2006, this document has structural improvements.

There are many adjustments. See Appendix A for a comparison of the changes in the structure numbering among the four files.

Technical differences between this document and ISO 5350-1:2006, ISO 5350-2:2006, ISO 5350-3:2007 and ISO 5350-4:2006 the reasons are as follows.

a) The scope description has been changed (see Chapter 1) to conform to the rules for drafting standardization documents in my country;

b) ISO 3688 (see Chapter 1) has been replaced with the normatively referenced GB/T 8940.2 to adapt to my country's technical conditions;

c) The definitions of sample and impurity have been changed (see 3.3 and 3.4) for easier understanding by standard users;

d) ISO 5269-1 (see 4.2.3.3, 6.3.3 and 7.3.3) has been replaced with the normatively referenced GB/T 24324 to adapt to my country's technical standards.

Technical conditions;

e) ISO 5269-2 (see 4.2.3.3, 6.3.3 and 7.3.3) has been replaced with the normatively referenced GB/T 24326 to adapt to my country's technical standards.

Technical conditions;

f) ISO 5263-1 (see 4.2.3.2 and 4.3.2) has been replaced with the normatively referenced GB/T 24327 to accommodate Chinese technical standards.

condition;

g) ISO 5263-2 and ISO 5263-3 (see 4.2.3.2 and 4.3.2) have been replaced with the normatively referenced GB/T 29285 to accommodate [the standard].

my country's technological conditions;

h) ISO 7213 (see 4.3.1, 5.3.1, 6.3.1 and 7.3.1) has been replaced with the normatively referenced GB/T 740 to adapt to my country's technical standards.

Technical conditions;

i) ISO 638 (see 4.4.1 and 5.4.1) has been replaced with the normatively referenced GB/T 462 to adapt to my country's technical conditions;

j) The grouping of the first-level impurity area has been changed (see 4.4.3 and 4.5.1) to facilitate standardized operation for standard users;

k) Change the content of note 8.2 in ISO 5350-1:2006 to the main text (see 4.5.2) to adapt to my country's technical conditions;

l) The requirements for the water used to wet the samples have been increased (see 5.4.2) to adapt to my country's technical conditions;

m) The test report has been amended (see Chapter 8).

The following editorial changes have been made to this document.

a) The note in section 5.1 of ISO 5350-1:2006 and the content in section 5.2 stating that copies of standard dust comparison charts should not be used have been deleted;

b) Adjust the content of 8.1 in ISO 5350-3:2007 to 6.5.1.1 and 6.5.1.2;

c) Notes in Appendix A of ISO 5350-1:2006 and ISO 5350-2:2006 have been deleted.

Please note that some content in this document may involve patents. The issuing organization of this document assumes no responsibility for identifying patents.

This document was proposed by the China National Light Industry Council.

This document is under the jurisdiction of the National Technical Committee on Standardization of Paper Industry (SAC/TC141).

1 Scope

This document describes four methods for determining dust and fiber bundles in pulp. the transmitted light laboratory paper method, the transmitted light pulp plate method, and the reflected light method.

EBA visual method and reflected light EBA instrument method.

The transmission light laboratory paper method described in this document is applicable to all types of pulp, but primarily to non-plate pulp. It is not applicable to...

Recycled pulp. The transmission light pulp board method in this document applies to pulp boards, but not to unbleached sulfate pulp or any pulp that cannot be bleached due to excessive opacity.

Other pulp boards subjected to minimum size or minimum contrast impurity detection are also not suitable for recycled pulp. This document describes the reflected light EBA visual inspection method.

Applicable to all types of dry or wet pulp, and also to recycled pulp. The reflected light EBA instrument method in this document is applicable to impurity equivalent black surfaces.

Pulp with a particle size between 0.02 mm² and 3.0 mm² and a D65 brightness (measured according to GB/T 8940.2) of not less than 30% is also suitable for recycling.

pulp.

Note 1.Fiber bundles in mechanical pulp are usually determined by sieving or optical analysis. Some grades of mechanical pulp may be determined by laboratory paper making or...

Problems arose during the testing process, and the transmission light laboratory paper method could not be used for effective measurement.

Note 2.The maximum basis weight range for pulp slabs is generally 800g/m² to 1000g/m². If the basis weight of the pulp slab is too high or it becomes very opaque for other reasons, [further measures should be taken].

The laboratory paper method using transmitted light.

Note 3.For thick slurry plates with obvious surface texture or varying density, wetting the slurry plate will cause optical changes, distorting the observed impurity size and thus reducing the optical accuracy.

Accuracy of impurity size determination. For this type of sample, the transmitted light laboratory paper method is used.

Note 4.The results of the reflected light EBA visual method and the reflected light EBA instrument method only represent the number of impurities visible on or near the surface of the slurry plate, and cannot detect embedded impurities.

Impurities in the slurry board.

Note 5.If the surface of the pulp board is very rough or has obvious texture, the pulp board should be prepared into laboratory paper before the EBA instrument method of reflected light is used for measurement.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

GB/T 462 Determination of moisture content in analytical samples of paper, paperboard and pulp (GB/T 462-2023, ISO 287:2017, ISO 638-1.

2022, ISO 638-2:2022, MOD) GB/T 740 Sampling of pulp samples (GB/T 740-2003, ISO 7213:1991, IDT) GB/T 8940.2 Preparation of pulp brightness (whiteness) test specimens (GB/T 8940.2-2002, ISO 3688:1999, EQV) GB/T 24324 Preparation of laboratory paper for physical testing of pulp - Conventional sheet forming method (GB/T 24324-2009) ISO 5269-1:2005, MOD) GB/T 24326 Preparation of laboratory paper for physical testing of pulp - Rapid Kaiser process (GB/T 24326-2009, ISO) 5269-2.2004, MOD) GB/T 24327 Laboratory wet dissociation of pulp - Chemical pulp dissociation (GB/T 24327-2009, ISO 5263-1:2004, MOD) GB/T 29285 Laboratory wet dissociation of pulp - Mechanical pulp dissociation (GB/T 29285-2012, ISO 5263-2:2004) ISO 5263-3:2004, MOD)

3 Terms and Definitions

The following terms and definitions apply to this document.