Tissue World Milan Energy Savings from Advances in Tissue Suction Pressure Roll Venting

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2 Tissue World Milan Energy Savings from Advances in Tissue Suction Pressure Roll Venting

3 Optimizing the Press With Complimentary Roll Cover and Press Felt Designs Roll Covers Press Felts Venting Engineer roll covers to manage water drainage velocity through optimum nip intensity and width Design felts for quick saturation, drainage, pressing uniformity, sheet smoothness, and reducing rewet Engineer effective void volume to compliment felt design, evacuate water, and reduce rewet

4 Engineering Effective Void Volume There are many opportunities for optimization Optimize suction through holes Utilize double drilled suction holes Larger blind drilled hole patterns Blind drilled and grooved patterns Special groove geometry for soft covers 4 4

5 Double Drilled Case Studies Tissue Crescent Former Double Drilled SPR Increased vacuum assisted open area from 16.8% to 22.6% Light Weight 14.3 GSM Increased Speed From 767 m/min to 804 m/min (4.8% Increase) Heavy Weight 24.4 GSM Increased Speed from 562 m/min to 604 m/min (7.5% Increase) Assumptions: 14% incoming solids Dryer limited based on GJ/day Existing Open Area: 16.8% Double Drill Open Area: 22.6%

6 14.3 GSM (Existing) Press Roll Data MidWest NA Speed: 767 m/min Paper Type: TISSUE Grammage: Solids In: 14 % Solids Out: 39.5% Press Load: 88 kn/m Results Dryness In: 14 % Water In: 87.8 GSM Dryness Out: 39.5% Water Out: 21.9 GSM Water Removed: Total H2O: Total Void Volume: Excess Void Volume: 65.9 GSM 1066 GSM 1124 GSM 58 GSM Total Press Void Volume vs. Days Excess VV Min Excess VV Top Side Roll Cover Trade Name: yankee Cover Hardness(P&J): 0.1 Diameter: 3657 mm Felt Weight: 1342 GSM Caliper: 2.5 mm Air Perm: CFM Scanpro: 1000 GSM Bottom Side Roll Cover Trade Name: XTREME TS (Rubber) Cover Hardness(P&J): 24 Diameter: mm Thickness: mm Suction Dia: 3.9mm %OA 16.8 Total OA: 16.8 Void Vol: 587 GSM Felt Void Volume vs. Days Felt VV Felt H2O Roll H2O

7 14.3 GSM (Double Drill) Press Roll Data MidWest NA Speed: 804 m/min Paper Type: TISSUE Grammage: Solids In: 14 % Solids Out: 40.6% Press Load: 88 kn/m Results Top Side Roll Bottom Side Roll Dryness In: 14 % Water In: 87.8 GSM Cover Trade Name: yankee Cover Trade Name: XTREME TS (Rubber) Dryness Out: 40.60% Water Out: 20.9 GSM Cover Hardness(P&J): 0.1 Cover Hardness(P&J): 41 Water Removed: 66.9 GSM Diameter: 3657 mm Diameter: 838 mm Thickness: 25 mm Total H2O: 1067 GSM Suction Dia: 4.6 mm %OA 22.6 Total Void Volume: Excess Void Volume: 1357 GSM 290 GSM Felt Weight: 1342 GSM Total OA: 22.6 Void Vol: 791 GSM Total Press Void Volume vs. Days Caliper: 2.5 mm Air Perm: CFM Scanpro: 1000 GSM Felt Void Volume vs. Days Excess VV Min Excess VV Felt VV Felt H2O Roll H2O

8 Summary Existing Open Area: 16.8% Double Drill Open Area: 22.6%

9 Engineering Effective Void Volume - EnerVent Grooving Equal open area and effective void volume can be achieved many ways

10 EnerVent Grooves Case Study 1 Tissue C-Wrap Former 14.7 GSM Basis Weight / 1920mpm speed No Groove Suction Only 20.6% open area Grooved - Suction EnerVent % open area Analysis: Grab Samples PPRC Benefits: Increased mean solids 0.37% (39.13% to 39.50%) Additional Benefits: Significantly reduced 2-sigma CD moisture profile (50%) Existing: Open Area: 20.6% Suction EnerVent: Open Area: 38.5%

11 EnerVent Grooves Case Study 2 Tissue C-Wrap Former 35.8 GSM Basis Weight No Groove Suction Only 21% open area Grooved - Suction EnerVent % open area Analysis: Grab Samples PPRC vs Machine Speed: Rezolve calculated water removal in SPR Benefits: Slight improvement in mean solids (45.6% to 45.7%) Increased speed 1296 m/min to 1313 m/min (1.3% Increase) Increased calculated water removed 1011 L/min to 1026 L/min (1.5% Increase) Additional Benefits: Significantly reduced 2-sigma CD moisture profile (50%) Eliminated late life hole plugging Similar sheet solids exiting SPR (0.1% Increase) but 1296 m/min to 1313m/min speed increase (1.3%)

12 EnerVent Grooves Case Study 2 Tissue C-Wrap Former 35.8 GSM Basis Weight No Groove Suction Only 21% open area Grooved - Suction EnerVent % open area Analysis: Grab Samples PPRC vs Machine Speed: Rezolve calculated water removal in SPR Calculated water removed from SPR Increased from 1011 L/min to 1026 L/min 1.5% Increase

13 Energy Savings from Advances in Tissue Suction Pressure Roll Venting Suction hole double drilling Suction hole & Enervent grooving Paper Felt Topstock Base Increase of open area by double drilling of suction holes Increase of open area by adding enervent grooves Core Increasing vacuum surface open area can reduce rewet & allows water to evacuate faster into the open area Geometrically incapable of closing More consistent in-the-nip surface open area Void volume remains effective Retained water stays closer towards cover surface