Deinking chemistry performance: from laboratory flotation tests to - PowerPoint PPT Presentation

Deinking chemistry performance: from laboratory flotation tests to the simulation of an industrial pre-flotation line D. Beneventi, B. Carré, T. Hannuksela and S. Rosencrance 2ry stage Froth 2ry stage Air Air Cell Cell 2 1 1ry stage Froth 1ry stage Air Air Air Air Air Air Cell Cell Cell Cell Cell Cell 1 2 3 4 5 6 Floated pulp Pulp feed

Guideline � Motivations and objectives � Materials and methods • Laboratory flotation test procedure • Data analysis and process simulation � Results • Laboratory flotation tests • Process simulation � Conclusions DB– September, 2007 2

Motivations and objectives � Extrapolation of laboratory flotation tests to the industrial scale difficult/misleading � Absence of a laboratory test/data analysis procedure to interpret and simulate the action of deinking chemicals at lab and industrial scale � To develop a lab test procedure and a simulation tool to predict the influence of process chemistry on deinking selectivity in industrial lines Data analysis and Selectivity in Lab benchmark process simulation industrial lines test DB– September, 2007 3

Guideline � Motivations and objectives � Materials and methods • Laboratory flotation test procedure • Data analysis and process simulation � Results • Laboratory flotation tests • Process simulation � Conclusions DB– September, 2007 4

Materials and methods Laboratory flotation test procedure High consistency pulping • Furnish: 50% OMG/50%ONP • Consistency: 13% • Temperature: 45°C • Pulping time: 15 min • Ca 2+ : 150 mg/L DB– September, 2007 5

Materials and methods Laboratory flotation test procedure High consistency Re-pulping chemistries tested in this study Re-pulping chemistries tested in this study pulping Re-pulping chemistry Re-pulping chemistry NaOH (%) NaOH (%) Silicate (%) Silicate (%) Peroxide (%) Peroxide (%) Collector (%) Collector (%) Soap, 2% silicate Soap, 2% silicate 0.7 0.7 2 2 0.7 0.7 0.45 0.45 Soap, 1% silicate Soap, 1% silicate 0.7 0.7 1 1 0.7 0.7 0.45 0.45 Blend, 2% silicate Blend, 2% silicate 0.7 0.7 2 2 0.7 0.7 0.15 0.15 Blend, 1% silicate Blend, 1% silicate 0.7 0.7 1 1 0.7 0.7 0.15 0.15 • Furnish: 50% OMG/50%ONP • Consistency: 13% • Temperature: 45°C • Pulping time: 15 min • Ca 2+ : 150 mg/L DB– September, 2007 6

Materials and methods Laboratory flotation test procedure Laboratory continuous flotation High consistency pulping • Consistency: 0.8% • Temperature: ~40°C • Ca 2+ : 150 mg/L Adjustable froth removal Pulp chest • Furnish: 50% OMG/50%ONP • Consistency: 13% Froth • Temperature: 45°C collection • Pulping time: 15 min • Ca 2+ : 150 mg/L Air Floated To vacuum pulp pump DB– September, 2007 7 Pulp aeration line

Materials and methods Laboratory flotation test procedure Laboratory continuous flotation High consistency pulping • Consistency: 0.8% • Pulp feed flow: 2 L/min • Temperature: ~40°C • Ca 2+ : 150 mg/L Adjustable froth removal Pulp chest • Furnish: 50% OMG/50%ONP • Consistency: 13% Froth • Temperature: 45°C collection • Pulping time: 15 min • Ca 2+ : 150 mg/L Air Floated To vacuum pulp pump DB– September, 2007 8 Pulp aeration line

Materials and methods Laboratory flotation test procedure Laboratory continuous flotation High consistency pulping • Consistency: 0.8% • Pulp feed flow: 2 L/min • Air flow: 4 L/min • Temperature: ~40°C • Ca 2+ : 150 mg/L Adjustable froth removal Pulp chest • Furnish: 50% OMG/50%ONP • Consistency: 13% Froth • Temperature: 45°C collection • Pulping time: 15 min • Ca 2+ : 150 mg/L Air Floated To vacuum pulp pump DB– September, 2007 9 Pulp aeration line

Materials and methods Laboratory flotation test procedure Laboratory continuous flotation High consistency pulping • Consistency: 0.8% • Pulp feed flow: 2 L/min • Air flow: 4 L/min • Temperature: ~40°C • Ca 2+ : 150 mg/L • Cell volume: 14.5 L Adjustable froth removal Pulp chest • Furnish: 50% OMG/50%ONP • Consistency: 13% Froth • Temperature: 45°C collection • Pulping time: 15 min • Ca 2+ : 150 mg/L Air Floated To vacuum pulp pump DB– September, 2007 10 Pulp aeration line

Materials and methods Laboratory flotation test procedure Laboratory continuous flotation High consistency pulping • Consistency: 0.8% • Pulp feed flow: 2 L/min • Air flow: 4 L/min • Temperature: ~40°C • Ca 2+ : 150 mg/L • Cell volume: 14.5 L • Froth removal thickness: 1, 2, 3, 5 cm Adjustable froth removal Pulp chest • Furnish: 50% OMG/50%ONP • Consistency: 13% Froth • Temperature: 45°C collection • Pulping time: 15 min • Ca 2+ : 150 mg/L Air Floated To vacuum pulp pump DB– September, 2007 11 Pulp aeration line

Materials and methods Laboratory flotation test procedure Laboratory continuous flotation High consistency Pulp characterization pulping • ERIC, Brightness • Ash content (475°C), fibre content • Mass flow Adjustable froth removal Pulp chest • Furnish: 50% OMG/50%ONP • Consistency: 13% Froth • Temperature: 45°C collection • Pulping time: 15 min • Ca 2+ : 150 mg/L Air Floated To vacuum pulp pump DB– September, 2007 12 Pulp aeration line

Guideline � Motivations and objectives � Materials and methods • Laboratory flotation test procedure • Data analysis and process simulation � Results • Laboratory flotation tests • Process simulation � Conclusions DB– September, 2007 13

Materials and methods Data analysis and process simulation Flotation de-inking modelling Flotation Adjustable froth removal Pulp chest α K Q dc = − n g n c n dt S ⋅ α K Q = n g k n S Air S cell cross section d Q g air flow c n particle concentration K n experimental flotation rate Pulp aeration line DB– September, 2007 14

Materials and methods Data analysis and process simulation Flotation de-inking modelling Entrainment Adjustable froth removal Pulp chest φ ⋅ 0 Q dc = − f n c n dt V V cell volume 0 water upstream flow Q f Air c n particle concentration d φ entrainment coefficient Pulp aeration line DB– September, 2007 15

Materials and methods Data analysis and process simulation Flotation de-inking modelling Frothing Adjustable froth removal Pulp chest Q ε = f + Q Q f g − ⋅ ε = ε ⋅ L d FRT e 0 ε Air water holdup d ε 0 water holdup at the froth/pulp interface Q f water upstream flow Q g gas flow Pulp aeration line FRT froth retention time L d water drainage coefficient DB– September, 2007 16

Materials and methods Data analysis and process simulation Flotation de-inking modelling Drainage Adjustable froth removal Pulp chest dM = δ − ⋅ ⋅ f c Q nf d dt dM f /dt particle drainage rate δ particle drainage coefficient Air c nf particle concentration in the froth d Q d water drainage flow Pulp aeration line DB– September, 2007 17

Materials and methods Data analysis and process simulation Flotation de-inking modelling Adjustable froth removal Pulp chest Experimental Laboratory data fitting with flotation tests model equations Air d Pulp aeration line Extraction of Process scale-up Industrial line transport and design using simulation coefficients model equations DB– September, 2007 18

Materials and methods Data analysis and process simulation Industrial pre-flotation line Parameters used to simulate an industrial pre-flotation unit Cell Cell cross section Pre-flotation feed Cell nominal Gas flow Number of Number of Recirculation rate 2 ) volume (L) area (m flow (L/min) flow (L/min) (L/min) 1ry cells 2ry cells on 2ry cells (%) 24000 12 30000 40000 20000 6 2 71 DB– September, 2007 19

Materials and methods Data analysis and process simulation Industrial pre-flotation line Parameters used to simulate an industrial pre-flotation unit Cell Cell cross section Pre-flotation feed Cell nominal Gas flow Number of Number of Recirculation rate 2 ) volume (L) area (m flow (L/min) flow (L/min) (L/min) 1ry cells 2ry cells on 2ry cells (%) 24000 12 30000 40000 20000 6 2 71 2ry stage Froth 2ry stage Air Air Cell Cell 2 1 1ry stage Froth 1ry stage Air Air Air Air Air Air Cell Cell Cell Cell Cell Cell 4 5 6 1 2 3 Floated pulp DB– September, 2007 20 Pulp feed

Guideline � Motivations and objectives � Materials and methods • Laboratory flotation test procedure • Data analysis and process simulation � Results • Laboratory flotation tests • Process simulation � Conclusions DB– September, 2007 21