EFFECTS OF TALC APPLICATION ON PAPER MACHINE RUNNABILITY. Marcelo Takeda Xilolite Marcelo Costa Suzano

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1 EFFECTS OF TALC APPLICATION ON PAPER MACHINE RUNNABILITY Marcelo Takeda Xilolite Marcelo Costa Suzano

2 Agenda Introduction Objectives Mill Trial Events Results and Discussion Conclusion

3 Main Talc Application Aspects on Cellulose Pulp Colloid contend in the first step of process. Washing efficiency. Thermal and ph chocks during the process. Dosage points. Talc distribution on the dosage point. Colloidal profile and dirtiness level. Good talc dispersion.

4 Wet End Trash Inorganic Organic tals GlucA s HexA s Cell - COOH Extractives ASA hydrolyzed AKD hydrolyzed Residual Lignin CH 3 (CH 2 ) 14 COOH Ácido Palmítico (ex. ác. graxo) OCO(CH 2 ) n CH 3 OCO(CH 2 ) n CH 3 OCO(CH 2 ) n CH 3 Triglicerídeos CO 2 H Ácido Desidroabiético (ex. ácido resinóico) 17 HO Sitosterol 8 O O Oleato de Colesterol (ex. éster esteroiral) Extractives examples Reaction of ASA with water and formation of dicarboxylic acid (alkenyl succinic acid) and salt formation.

5 Main Talc Application Aspects on Paper Machine Colloids at Headbox. Refining level. Circuit closure. Quantity and quality of Cutting Paper. Talc dosage Before Refining Tank. Levelbox Colloidal profile and dirtiness level. Good talc dispersion.

6 Objectives Demonstrate the efficiency of hydrophobic organic trash control with talc application at wet end system and its effects on the Paper Machine Runnability during the mill trial experience under real production conditions. The relationship between sheet breaks and those colloids. Impact on cost reduction and Pulp & Paper quality.

7 Mill Trial Events Talc dosage strategy and the main actions in this period were: 1. Talc application in the Wet End system right before the Refine Storage Tank (RST 0.5 kg/t ) and Level Box (LB 0.5 kg/t ). Started on April 2007 until June All coated paper broke were deviated to PM1 in order to stabilize the PM2 system since July Talc redistribution in the fiber line that works inline supplying pulp to all paper machines. 4. Evaluation of raw material impact on the colloidal system and consequently on the dirtiness formation onto the sheet paper. 5. Gradual removal of some cationic agents used in the Wet End, such as aluminum sulfate, PAC (poly aluminum chloride) and coagulants.

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9 BEKP Visible Dirt Count mm 2 /m /11/07 20/12/07 20/1/08 20/2/08 20/3/08 20/4/08 20/5/08 20/6/08 20/7/08 20/8/08 20/9/08 20/10/08 20/11/08 20/12/08 New Defoamer Mill trial 20/1/09 20/2/09 20/3/09

10 Wet End Extractives Hydrophobic EBKP Extractives ton/hour ton/day ton/year PM Minimum PM Maximum Average ketone-soluble fraction, % over dry mass

11 Wet End Trash Inorganic Organic tals GlucA s HexA s Cell - COOH Extractives ASA hydrolyzed AKD hydrolyzed Residual Lignin CH 3 (CH 2 ) 14 COOH Ácido Palmítico (ex. ác. graxo) OCO(CH 2 ) n CH 3 OCO(CH 2 ) n CH 3 OCO(CH 2 ) n CH 3 Triglicerídeos CO 2 H Ácido Desidroabiético (ex. ácido resinóico) 17 HO Sitosterol 8 O O Oleato de Colesterol (ex. éster esteroiral) Extractives examples Reaction of ASA with water and formation of dicarboxylic acid (alkenyl succinic acid) and salt formation.

12 Main causes of sheet breaks in downtime hours and percentage. Sheet breaks / hours % Average 2007 Causes PM1 PM2 PM1 PM2 AVG Dirtiness Cut NI Shrink Total chanical events were not considered.

13 PM2 - Daily sheet breaks Main causes of sheet breaks in percentage of downtime hours Most of the unidentifiable sheet breaks happens due to imperceptible holes causing rupture points. NI 31.3% Shrink 0.7% Dirtiness 61.3% y = 0.049x x R 2 = PM1 - Daily sheet breaks Cut 6.7%

14 Daily Sheet Breaks on the PM1 vs. Colloids asurements Colloids, x 10 6 particules/cm 3 9 Headbox Level box White Water Mix Tank Colloids, x 10 6 particules/cm Broke HeadBox y = 7.01x x R 2 = 0.90 y = 0.70x x R 2 = R 2 = Daily sheet breaks on PM1 6 R 2 = R 2 = R 2 = Colloids into Broke Tank x 10 6 particles/cm 3

15 Talc Effect on the Colloidal System Colloid index reducing in % x Talc dosage 89% 67% White Water % 67% 3.00 Head Box 54% 43% 2.00 Level Box 32% 22% 1.00 Mix Tank 100% 80% 60% 40% 20% 0% 1, kg/ton Kg/ton 0, kg/ton Kg/ton

16 PM1 - Daily sheet breaks Daily Sheet Breaks on the PM / kg/ton RST / kg/ton BT 19/ kg/t 0.67 kg/ton (RST) kg/ton(bt) 11/jun 0.5kg/ton (RST) + 0.5kg/ton (LB) Média do Período = 2,22 0 Average/06 January/07 February/07 March/07 April/07 May/07 June/07 July/07 August/07 September/07 October/07 November/07 December/07 January/08 February/08 March/08 April/08 May/08 June/08 July/08 August/08 September/08 October/08 November/08 December/08 Sheet Breaks Decrease #1.66

17 Absorbância chanism of Talc Retention on Cellulose Colloid Agglomeration Talc effect no Agglomeration Talc Retention 75-80% A PI B cm -1

18 Economical Results Runnability gain - Apr/2007 to Dec/2008. Sheet Breaks reduction MB 1 decrease in 1.66 breaks/day MB 2 decrease in 0.96breaks/day Downtime MB 1 gain of 9.47 h/month MB 2 gain of 8.30 h/month Extra production gain 2007/2008 MB ton MB ton Total USD 1.6 MM

19 Conclusions 1. The number of sheet breaks is associated with the colloids profile in the wet end system (higher values indicates poor runnability); 2. Dosing talc improves significantly the runnability. ( ~ 1.66 sheet breaks per day); 3. There is a high correlation between the downtime length and the number of sheet breaks on both PM. The sheet breaks must have the same origin related to the colloidal system and the dirt generation. 4. Microscopic agglomerates form rupture points onto paper web. So the major cause of sheet breaks is connected to colloids, dirtiness and unidentifiable represent more than 90% for PM1.

20 Conclusions 5. Semi-analytic IR analysis indicated that the lamellar talc particles adsorbs lipophilic material from water system. There s a retention around 75-80%. 6. Other chemicals used in the paper recipe contributes to the formation of colloids or in its instability. 7. For further work: (a) Optimization of talc and coagulants dosage at paper machines. (b) The formation of composite (talc + hydrophobic compounds) should be investigated.

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