ISO 21993:2020 Paper and pulp — Deinkability test for printed paper products

The two key steps are ink detachment and ink removal
Good deinkability of printed paper products is crucial for the sustainability of the graphic paper loop. The key process steps for deinking are the detachment of the ink film from the paper, ink fragmentation into a suitable size range and removal from the pulp slurry. Flotation deinking under alkaline conditions is the most widely used technology for ink removal in the paper recycling process. A wider range of the process pH may be utilised for separately collected printed products on predominantly woodfree substrates.
A simplified method herein has been developed to simulate the principle process steps for ink detachment and ink removal under standardised alkaline conditions at a laboratory scale. This gives an indication on how print products will perform in an industrial deinking operation. The method defined in this document is based on INGEDE Method 11. When the first version of INGEDE Method 11 was published, the deinking industry was predominantly using wood-containing raw material. INGEDE Method 11 is widely used by the paper industry and by many stakeholders in the paper value chain.
The method is not designed to model additional or alternative process steps, such as dispersing, post-flotation, washing and bleaching. Cleaning and screening stages, which are designed to remove impurities and unwanted materials in the industrial process, are also not included in this method. An alternative deinking test method with near‐neutral or neutral flotation conditions may be suitable for paper products mainly consisting of woodfree pulp fibres. However, the near‐neutral or neutral flotation conditions are not within the scope of this document.
A method to estimate the challenge of a print product to the deinking process

This document specifies a basic laboratory test method for deinkability, applicable to any kind of printed paper product, under alkaline conditions using single-stage flotation deinking and fatty acid-based collector chemistry.

The method is meant to evaluate the relative challenges a printed product means in the deinking process, consisting of the basic two steps: the release of ink from the fibre and the concurrent removal of the ink from the system. The evaluation of the results needs a matching scorecard. The Deinkability Scorecard of the European Paper Recycling Council refers to results achieved with INGEDE Method 11 and can also be used to evaluate results from a test according to ISO 21993.

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