Background. Material and Methods. Results. Outlook

Transcription

1 Influence of digital print products on the deinking behaviour of paper for recycling mixtures in a 2-stage deinking process INGEDE Symposium, , Munich Technische Universität Darmstadt Paper Technology and Mechanical Process Engineering (PMV) Dipl.-Ing. Saskia Runte Dr.-Ing. Hans-Joachim Putz Picture: Krebs, T., PMV February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 1 Outline Background Material and Methods Results Outlook February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 2

2 Outline Background Material and Methods Results Outlook February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 3 Deinkability of different printing inks Currently, a one-stage flotation process is used to evaluate the deinkability of individual printed products in laboratory scale using INGEDE Method 11 Source: Faul, A.: Wie ökologisch ist der Digitaldruck? Presentation at: PrintCongress 2012, 9. Oktober 2012, Stuttgart How can a 2-loop process be implemented in laboratory scale? How do the deinking result differ between both methods? February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 4

3 Trend of printing volume of offset, gravure and digital printing for North America and Western Europe Billion A4 per year Offset- and rotogravure printing Digital printing Source: Paul & Maess: Qualitätsbestimmende Wechselwirkungen im Digitaldruck. In: Wochenblatt für Papierfabrikation 138 (2010) 2 What influence has the changing composition of paper for recycling and the increasing amount of difficult or non-deinkable products on the deinking behaviour in a 2-loop process? February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 5 Outline Background Material and Methods Results Outlook February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 6

4 Paper for recycling products analysed Newspaper Offset-coldset Two-sided Advertising Offset-heatset Two-sided Magazine Offset-heatset Coated Two-sided Magazine Rotogravure Two-sided Test print Inkjet, pigment Two-sided Test print Liquid toner Coated Two-sided The deinking behaviour depends on different parameters like the printing ink and process, the unprinted paper grades, Thus, the results and conclusions in this presentation are only valid for the products and mixtures analysed February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 7 Rough comparison between INGEDE Method 11 and the newly developed 2-loop deinking process INGEDE Method 11 Ageing Defibration 2-loop Method Ageing Defibration Storage 1. Flotation Storage Thickening Dispersion 1. Flotation 2. Flotation February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 8

5 2-Loop deinking process in laboratory scale (1) Printing product or mixture Oven: t = 72 h T = 60 C Hobart Pulper: c fibre = 12 % t = 20 min T = 45 C m = 200 g b.d. Speed = 2 Ageing Defibration (2x) 0,6 % NaOH 1,8 % Sodium silicate 0,7 % H 2 O 2 0,8 % Oleic acid Comparison INGEDE Method 11: c solid = 15 % Water bath: c = 5 % t = 60 min T = 45 C Storage UP Undeinked pulp: 2 Handsheets 2 Filter pads Voith Delta 25: c = 0,8 % t = 6 min T = 45 C m = 180 g b.d 1. Flotation (2x) DP 1 February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 9 Comparison Deinked pulp 1: INGEDE Method 11: 2 Handsheets t = 12 min 2 Filter pads 2 Membrane filters 2-Loop deinking process in laboratory scale (2) Thickening TF Thickening filtrate: 2 Membrane filters Thickening CEPA Laboratory Centrifuge LS (for example): Speed = r.p.m. Filter bag = 11 µm Pulp Filtrate Use of thickening filtrate for 2. flotation Source: Runte, S.; Putz, H.-J.: Synergistische und antagonistische Effekte beim Deinken von Altpapiermischungen. In: Abschlussbericht zu IGF-Projekt N, TU Darmstadt, Papierfabrikation und Mechanische Verfahrenstechnik, 2017 February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 10

6 2-Loop deinking process in laboratory scale (2) CEPA Laboratory Centrifuge LS: Speed = r.p.m. Filter bag = 11 µm Cavimix 1031: c = 29 % t = 2 min T = 70 C m = 200 g b.d Thickening Dispersion Thickening filtrate TF DSP Thickening filtrate: 2 Membrane filters Dispersed pulp (with TF): 2 Handsheets 2 Filter pads Source: Schabel, S.: Möglichkeiten und Grenzen der Verwertung von gemischtem Altpapier (1.02) für die Herstellung grafischer Papiere. In: Abschlussbericht zu IGF-Projekt N, TU Darmstadt, Papierfabrikation und Mechanische Verfahrenstechnik, 2014 February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 11 2-Loop deinking process in laboratory scale (2) CEPA Laboratory Centrifuge LS: Speed = r.p.m. Filter bag = 11 µm Cavimix 1031: c = 29 % t = 2 min T = 70 C m = 200 g b.d Thickening Dispersion Thickening filtrate TF DSP Thickening filtrate: 2 Membrane filters Dispersed pulp (with TF): 2 Handsheets 2 Filter pads Voith Delta 25: c = 0,8 % t = 4 min T = 45 C m = 180 g b.d 2. Flotation (1x) 0,2 % NaOH 0,3 % Oleic acid DP 2 Deinked pulp 2: 2 Handsheets 2 Filter pads 2 Membrane filters Picture: Krebs, T., PMV February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 12

7 Outline Background Material and Methods Results* Outlook * Based on: Wali S.: Untersuchung und Modellierung des Deinkingverhaltens von Altpapiermischungen. TU Darmstadt, PMV, Masterarbeit, 2017 February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 13 Comparison of brightness after final deinking using INGEDE Method 11 and the 2-loop method 85 INGEDE method 11 - undeinked INGEDE method 11 - deinked 87,0 85,3 80,0 79,9 Brightness in % Loop method - undeinked 2-Loop method - deinked 53,3 52,6 50,3 46,6 40,9 39,7 28,8 29,5 66,1 63,2 46,8 47,4 56,7 52,5 36,5 34,5 41,5 37,9 INGEDE method 11 - undeinked 32,0 33,1 INGEDE method 11 - deinked Newspaper Offset-coldset Advertising Offset-heatset Magazine Coated Offset-heatset Magazine Rotogravure 2-Loop method - undeinked 2-Loop method - deinked Test page print Test page print Coated Inkjet (pigment) Liquid toner February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 14

8 Comparison of filtrate darkening after final deinking using INGEDE Method 11 and the 2-loop method Filtrate darkening Y ,3 INGEDE Method 11 - deinked 2-Loop Method - deinked 3,7 Newspaper Offset-coldset 5,0 5,9 Advertising Offset-heatset February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 15 1,3 Magazine Coated Offset-heatset 7,7 7,8 3,3 Magazine Rotogravure 38,6 76,3 Test print Inkjet (pigment) 1,7 3,2 Test print Coated Liquid toner Comparison of dirt particle area after final deinking using INGEDE Method 11 and the 2-loop method Dirt particle area in mm²/m² INGEDE Method 11 - deinked 2-Loop Method - deinked 119 Newspaper Offset-coldset Advertising Offset-heatset Magazine Coated Offset-heatset Magazine Rotogravure Test print Inkjet (pigment) Test print Coated Liquid toner February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 16

9 Investigation of the deinking behaviour of paper for recycling mixtures Starting point is a simplified paper for recycling mixture without digitally printed products Substitution of individual printed products with digital printed test prints February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 17 Influence of the amount of digitally printed test prints in paper for recycling mixtures on brightness ,7 60,5 Brightness R 457 in % ,5 54,2 50,1 40,1 55,3 49,3 46,9 37,6 53,9 46,0 43,9 47,3 56,4 55,9 53,0 51,5 41, , Reference 10 % Inkjet 30 % Inkjet 30 % Indigo 30 % Inkjet + 30 % Indigo Undeinked Mixture 1. Flotation Dispersion 2. Flotation February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 18

10 Influence of the amount of digitally printed test prints in paper for recycling mixtures on filtrate darkening Flotation Dispersion 2. Flotation 25,6 Filtrate darkening Y ,9 11,6 10,1 16,6 10,9 20,2 10,2 5 2,8 4,1 4,1 5,4 4,8 4,8 0 Reference 10 % Inkjet 30 % Inkjet 30 % Indigo 30 % Inkjet + 30 % Indigo February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 19 Influence of the amount of digitally printed test prints in paper for recycling mixtures on dirt particle area Dirt particle area in mm²/m² Flotation 2. Flotation Reference 10 % Inkjet 30 % Inkjet 30 % Indigo 30 % Inkjet + 30 % Indigo February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 20

11 Deinking of paper for recycling mixtures Comparison of optical properties of paper for recycling mixtures after final deinking using the INGEDE Method 11 (I.M. 11) and the 2-loop method (2-loop) February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 21 Summary At PMV, a 2-loop method was developed to simulate a two-stage deinking process in laboratory scale: In comparison to INGEDE Method 11, the brightness is mostly affected positively and dirt specks were reduced, but the filtrate darkening increases for individual print products Paper for recycling mixtures with increasing amounts of digital test prints were analysed: Due to increasing inkjet test prints, the brightness of the paper for recycling mixtures decreases slightly. Adding Indigo test prints to the mixtures, the brightness rises The filtrate darkening rises due to an increasing amount of Inkjet test prints Dirt specks of the mixtures decrease a little due to an increasing amount of inkjet test prints, but rise if Indigo test prints are added to the mixture February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 22

12 Outline Background Material and Methods Results Outlook February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 23 Outlook Optimisation of the 2-loop method Improvement of dispersion step Adjustment of flotation time and flotation chemicals Investigation of additional paper for recycling mixtures Digital print products from the market instead of test prints Further percentage substitutions with digital print products Development of a scheme to assess the deinking behavior of paper for recycling mixtures February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 24

13 Thanks for your attention For further information contact Technische Universität Darmstadt Paper Technology and Mechanical Process Engineering (PMV) Dipl.-Ing. Saskia Runte Tel.: +49 (0) 6151 / Dr.-Ing. Hans-Joachim Putz putz@papier.tu-darmstadt.de Tel.: +49 (0) 6151 / Funding The IGF project N of the research association Kuratorium für Forschung und Technik der Zellstoff- und Papierindustrie im VDP e. V. was funded via the AiF in the frame of a program for promotion of common industrial research and development (IGF) by the Federal Ministry of Economics Affairs and Energy (BMWi) on the basis of a decision by the German Federal Parliament. February 28 th 2018 Fachgebiet Papierfabrikation und Mechanische Verfahrenstechnik Saskia Runte 25