Optimization of Fiber Properties Using Single Pass Refining v/s Recirculation- A Case Study

Optimization of Fiber Properties Using Single Pass Refining v/s Recirculation- A Case Study

Yash Papers Ltd.• Yash Papers established in the year 1981 and is located in Faizabad,

Uttar Pradesh• We are agro based and use bagasse, wheat straw, gunny bags and a

portion of softwood as a raw material. The production capacity of the plant is 39,100 MT per annum

• We have three MG paper machine with capacity of PM 1- 30 MT/day PM 2- 30 MT/day PM 3- 70 MT/day• We have a Recovery Boiler of 140 MT Dry Solids/day capacity and

Power Plant of 6 MW capacity.• We make specialty and packaging grades of paper.

Objective

To optimize the fiber propertiesTo produce a paper with enhanced fiber

properties and hence value addition to existing product basket

To reduce energy consumption and long fiber consumption & hence reduction in cost of production

Approach

• To achieve better fiber strength properties we modified & optimized our refiner operations

• Installation of online measurement & control systems and automation

• Consistency optimization• Flow Optimization• Different grades of Long Fiber Optimization

TDR Overview

TDR Control Panel

Recirculation0SR 15 20 25 48

Recirculation Time

3.30 hrs. 4 hrs. 5 hrs. 8 hrs.

Cy% 4.2 4.2 4.2 4.2

Burst Factor 16.89 18.38 35.01 40.41

Tear Factor 103.70 137.03 140.86 104.22

Load 21”/17” (Amp)

180/160 180/160 180/160 180/160

Consistency Optimization

Consistency TrialConsistency% 4.5 4.2 3.9 3.5 3.3

Burst Factor 29.4 26 24.4 22.9 35.8

Tear Factor 196.9 185 187.5 191.5 190.4

Observation

• The Burst Factor increased by reducing the consistency of the pulp without affecting other properties

FLOW OPTIMIZATION

Flow@ 3.3% Consistency

• Flow @ 3.3% ConsistencyFlow Initial 20 m3/hr

After 21” Refiner

30 m3/hr After 21” Refiner



MT/hr 0.66 0.9 1.3 1.6

0SR 21 20 20 19

Burst Factor 11.8 42.9 39.6 37 35.8

Tear Factor 150.4 173.7 200 168.6 168.1

Refiner load 21”/17” (Amp)

180/160 90/91 120/100 160/155 180/163

Pressure (kg/cm2)

1.1 2.8 2.4 2.1 1.9

Flow@ 3.7% ConsistencyFlow Initial 20 m3/hr

After 21” refiner

30 m3/hr After 21”

refiner


refiner


refiner

MT/hr 0.7 1.1 1.5 1.9

0SR 20 18 17 15

Burst Factor 9.2 36.3 33.8 31 22.9

Tear Factor 101.4 204.7 206.3 191.9 173.2


180/160 85/92 120/126 165/136 170/164

Pressure (kg/cm2)

1.2 2.5 2.3 1.9 1.8

Flow @ 3.9% ConsistencyFlow Initial 20 m3/hr

After 21” Refiner




MT/hr 0.8 1.2 1.6 2.0

0SR 18 16 16 15

Burst Factor 9.9 33.1 28.6 27.6 24.4

Tear Factor 91.2 239.4 202.8 187.3 178.5


180/160 82/90 107/100 133/125 150/160

Pressure (kg/cm2)

1.1 2.8 2.4 2.1 1.9

Flow @ 4.1% consistencyFlow Initial 20 m3/hr

After 21” Refiner




MT/hr 0.8 1.2 1.6 2.1

0SR 19 18 17 15

Burst Factor 10.7 35.3 34.6 32 26

Tear Factor 105.4 200 192.6 176.2 157.5

Refiner Load 21”/17” (Amp)

180/160 100/104 120/126 130/132 140/137

Pressure (kg/cm2)

1.2 2.4 1.9 1.8 1.5

Flow @ 4.5% ConsistencyFlow Initial 20 m3/hr

After 21” Refiner




MT/hr 0.9 1.4 1.8 2.3

0SR 17 17 16 15

Burst Factor 9.7 31.7 30.3 29.4 25.6

Tear Factor 106.2 191.5 213.3 196.9 154.3

Refiner Load 21”/17” (Amp)

180/160 180/100 120/124 135/137 140/136

Pressure (kg/cm2)

1.1 2.5 2.1 1.8 1.5

Trends

3.3 3.7 3.9 4.1 4.505

101520253035404550

@ 20 m3/hr

3.3 3.7 3.9 4.1 4.505

1015202530354045

@ 30 m3/hr

3.3 3.7 3.9 4.1 4.505

10152025303540

@ 40 m3/hr

3.3 3.7 3.9 4.1 4.505

10152025303540

@ 50 m3/hr

BF

Cy%

BF

Cy%

BF

Cy%

BF

Cy%

Observation

• At any particular consistency, strength property is increasing with reduced flow rate level

• At any particular flow rate, it is observed that with decreasing stock consistency strength properties are better

Grades Selection & optimization of Long Fiber

Burst Factor @ 3.3% ConsistencyFlow (m3/hr) Grade 1 Grade 2 Grade 3

20 44.7 35.2 70.5

30 41.2 33.4 54.8

40 39.0 32.1 53.1


20 36.3 32.1 68.4

30 33.9 30.6 50.7

40 32.2 29.6 39.2


20 34.0 35.0 66.1

30 36.6 30.6 50.8

40 37.7 28.4 42.5

Trends

20 m3/hr 30m3/hr 40 m3/hr0

10

20

30

40

50

60

70

80

44.6941.23 3936.21 33.41 32.1

70.53

54.76 53.06

At Consistency 3.3%

20 m3/hr 30m3/hr 40 m3/hr0

10

20

30

40

50

60

70

34 36.65 37.7535.0230.56 28.41

66.12

50.8

42.46 Grade 1Grade 2Grade 3

At consistency 4.2%

BFBF

BF

20 m3/hr 30m3/hr 40 m3/hr0

10

20

30

40

50

60

70

80

36.3 33.9 32.232.1 30.6 29.6

68.36

50.74

39.21

At consistency 3.9 %

Observation

• Grade 3 of long fiber shows better strength properties as compared with other two grades

COST BENEFIT

Cost Benefit

• By using Single pass refining we achieved a reduction of 1% long fiber in the papermaking resulting in a saving of Rs. 1.18 crore

• The energy consumption observed decreased in single pass refining as compared to recirculation

• The paper produced through single pass refining shows better strength properties as compared to recirculation

• The paper thus produced added value by increased NSR

Cost Benefit by Softwood ReductionSerial No. Parameters September October

With Circulation Single Pass

1 Softwood 15% 14%

2 Bagasse Tear 42.0 41.6

3 Bagasse Burst Factor

16.07 15.82

4 Savings 15.0-14.0 = 1%

5 Softwood Saving/Month

18 Tons/Month

6 Saving/Year 216 Tons/Year

7 Cost 216*55000 = 1.18 Crore

Running Load Refiner running Load Data

Refiner Current (Amp) Power (Kwhr)

21” 180 109.73

17” 160 97.54

Power SavingSerial No. Particulars Recirculation Single Pass

1 Running Hours 13.25 6.97

2 Batch Size 50 m3 @ 4.2cy%= 2.10 MT

30 m3/hr. @ 3.3 cy%= 0.99 MT

3 Recirculation Time 4 hrs.

4 Net Output 2.14*(13.25/4)= 6.95 MT

0.99*6.97= 6.9 MT

5 Power Consumption/Day (Kw/Day)

2746.32 1444.71

6 Power Consumption/year (Kw/Year)

906285.6 476754.3

7 Power Consumption Saving/Year (Kw)

429531.3

8 Cost Saving (Per Unit Cost-Rs.3)

Rs. 12,88,593

THANK YOU

Documents

Optimization of Fiber Properties Using Single Pass Refining v/s Recirculation- A Case Study