Analysis of pulp components in Analysis of pulp components in a DIP process with tube flow a DIP process with tube flow fractionation fractionation Ossi Laitinen Laitinen Ossi Fibre and Particle Fibre and Particle Engineering Laboratory Engineering Laboratory 8th Research Forum on Recycling 26.09.2007
Outline Outline � Introduction Introduction � � Materials & Methods Materials & Methods � � Results Results � � Pulp component analysis Pulp component analysis � � Residual ink and brightness Residual ink and brightness � � Microscope analysis Microscope analysis � � Conclusions Conclusions � 8th Research Forum on Recycling 26.09.2007
Aim of study Aim of study � In this study fresh and aged raw material were In this study fresh and aged raw material were � compared in similar process conditions compared in similar process conditions � How aging affects to raw material, especially How aging affects to raw material, especially � behaviour of ink? behaviour of ink? � Fractional approach give answer to: Fractional approach give answer to: � � Detachment of ink in different fibre length class Detachment of ink in different fibre length class � � How much ink exits in each fibre length class? How much ink exits in each fibre length class? � � What is attached ink size distribution? What is attached ink size distribution? � 8th Research Forum on Recycling 26.09.2007
Introduction Introduction � Different environments to study aging and Different environments to study aging and � thermal aging: thermal aging: � Laboratory scale Laboratory scale � � Lack of actual process conditions Lack of actual process conditions � � Mill scale Mill scale � � Raw material changes Raw material changes � � Pilot scale Pilot scale � � Accurate raw material control Accurate raw material control � � Process conditions near industrial conditions Process conditions near industrial conditions � 8th Research Forum on Recycling 26.09.2007
Materials & Methods Materials & Methods � Pulps Pulps � � 1 1- -loop continuous deinking pilot plant loop continuous deinking pilot plant � � Raw material ONP Raw material ONP- -OMG (50% OMG (50%- -50%) 50%) � � Alkaline soap chemistry Alkaline soap chemistry � � Two separate trials in similar conditions: Two separate trials in similar conditions: � � Fresh material: 10 weeks old Fresh material: 10 weeks old � � Aged material: 30 weeks old Aged material: 30 weeks old � 8th Research Forum on Recycling 26.09.2007
Continuous deinking pilot plant Continuous deinking pilot plant sampling 8th Research Forum on Recycling 26.09.2007
Sampling points Sampling points Sampling point Description of the test point Drum pulper Samples from batch drum pulping Pulper accept tank Pulping samples after dilution (PAC) Flotation feed (FFE) Flotation cell feed samples Flotation accept (FAC) Flotation cell accept samples Flotation reject (FRE) Flotation cell reject samples Wire press outlet (WPO) Pilot process product (final pulp) 8th Research Forum on Recycling 26.09.2007
Pulping performances Pulping performances Pulping performances Raw material 50% ONP & 50% OMG (central European) Pulping 16% consistency Pulping 50°C temperature Pulping batch 35 kg (air dry) NaOH 10 [kg/t] Waterglass 9.3 [kg/t] Commercial fatty 6 [kg/t] acid soap H2O2 10 [kg/t] Hardness [°dH] 20 [°dH] adj. CaCl2 8th Research Forum on Recycling 26.09.2007
Analysis Analysis � Tube flow fractionation Tube flow fractionation � � Dry content and ash content Dry content and ash content � � Brightness and residual ink Brightness and residual ink � � Microscope and image analysis Microscope and image analysis � 8th Research Forum on Recycling 26.09.2007
Tube flow fractionation Tube flow fractionation � FR1: flakes (> 4mm) FR1: flakes (> 4mm) � Sample is separated Sample is separated � � into 4 fractions with into 4 fractions with � FR2: long fibres (1.85mm) FR2: long fibres (1.85mm) � continuous water flow continuous water flow � FR3: short fibres (0.6mm) FR3: short fibres (0.6mm) � � FR4: fines (< 0.2mm) FR4: fines (< 0.2mm) � 8th Research Forum on Recycling 26.09.2007
Laboratory measurements Laboratory measurements � Pulp dry content (ISO 638) Pulp dry content (ISO 638) � � Ash content of pulp (ISO 1762) Ash content of pulp (ISO 1762) � � Brightness of pulp (L&W Brightness of pulp (L&W Elrepho Elrepho � spectrophotometer) spectrophotometer) � Residual ink of pulp (L&W Residual ink of pulp (L&W Elrepho Elrepho � spectrophotometer) spectrophotometer) � Hyperwashing Hyperwashing (150 mesh wire screen) (150 mesh wire screen) � 8th Research Forum on Recycling 26.09.2007
Microscope and image analysis Microscope and image analysis � Each fraction was filtered out onto Each fraction was filtered out onto � membrane filter foils in order to investigate membrane filter foils in order to investigate the samples with a microscope (Leica Leica the samples with a microscope ( DCF320) DCF320) � Sample images were analysed with image Sample images were analysed with image � analysis software (Matrox Matrox Inspector) Inspector) that that analysis software ( calculated the number, length, width and calculated the number, length, width and area of dark particles (i.e. ink particles) area of dark particles (i.e. ink particles) 8th Research Forum on Recycling 26.09.2007
Results Results � Pulp component analysis Pulp component analysis � � Slushing rate, mass proportions of fractions Slushing rate, mass proportions of fractions � � Residual ink and brightness Residual ink and brightness � � Ink fragmentation, ink reduction, brightness Ink fragmentation, ink reduction, brightness � development development � Microscope analysis Microscope analysis � � Attached and free ink in different fractions Attached and free ink in different fractions � 8th Research Forum on Recycling 26.09.2007
Slushing rate in pulping Slushing rate in pulping � Aged material Aged material slushed slushed poorer during drum poorer during drum � pulping pulping Drum pulping 10 FR1 mass percentages [%] 9 8 7 6 5 4 3 2 1 0 10 min 20 min 30 min Fresh 4.8 3.7 2.9 Aged 8.5 8.1 5.9 8th Research Forum on Recycling 26.09.2007
Mass proportions of fractions Mass proportions of fractions � No considerable differences in mass proportions during No considerable differences in mass proportions during � process due to pumping and screening process due to pumping and screening Proportion of Proportion of Proportion of Proportion of Fresh pulp short fibres fines [%] flakes [%] long fibres [%] [%] Pulper (20min) 3.7 37.6 23.2 35.4 PAC 1.0 35.3 22.6 41.0 FFE 0.3 34.1 22.3 43.2 FAC 1.7 35.9 23.0 39.4 FRE 0.3 8.7 14.2 76.7 WPO 2.6 43.7 26.4 27.3 Proportion of Proportion of Proportion of Proportion of Aged pulp short fibres fines [%] flakes [%] long fibres [%] [%] Pulper (20min) 8.1 37.4 22.6 31.9 PAC 1.9 39.8 23.7 34.6 FFE 1.4 33.4 23.9 41.3 FAC 1.8 35.1 24.7 38.4 FRE 0.4 12.6 12.8 74.2 WPO 3.0 44.9 27.9 24.2 8th Research Forum on Recycling 26.09.2007
Residual ink Residual ink � Residual ink values were much higher in case of Residual ink values were much higher in case of � aged raw material aged raw material flotation accept & hyperwashing 2000 500 Residual ink [ppm] Residual ink [ppm] 400 1500 300 1000 200 500 100 0 0 PAC FFE FAC WPO FAC FAC HW Fresh 1291 1082 182 210 Fresh 182 132 1825 1611 460 474 460 298 Aged Aged HW = hyperwashing 8th Research Forum on Recycling 26.09.2007
Brightness Brightness � Brightness was 5 Brightness was 5- -8 point higher along the pilot 8 point higher along the pilot � process line process line 70 65 Brightness [% ISO] 60 55 50 45 40 35 30 PAC FFE FAC WPO Fresh 45.5 48.4 64.7 61.7 40.3 43.0 56.7 55.5 Aged 8th Research Forum on Recycling 26.09.2007
Microscopy analysis Microscopy analysis � FR2 & FR3 : Attached ink particles FR2 & FR3 : Attached ink particles � � FR4: Floatable free ink FR4: Floatable free ink � flotation accept flotation feed Total area of ink particles [pixels] Total area of ink particles [pixels] 1000000 1000000 100000 100000 10000 10000 1000 1000 FR2 FR3 FR4 FR2 FR3 FR4 Fresh 10530 16381 7955 Fresh 9722 18448 193099 12466 47827 131676 Aged 13566 34673 10114 Aged 8th Research Forum on Recycling 26.09.2007
Ink reduction in flotation Ink reduction in flotation Ink reduction [%] FR2 FR3 FR4 Total Fresh material ≈ 0 11 96 83 Aged material ≈ 0 28 92 71 − C C = ⋅ 100 %, F A E C C F � Free ink in FR4: Good removing during Free ink in FR4: Good removing during � flotation flotation � Attached in FR2 & FR3: Poor ink Attached in FR2 & FR3: Poor ink � reduction values reduction values 8th Research Forum on Recycling 26.09.2007
Recommend
More recommend
