Post on 17-Jan-2016
Paper Strength Increase by Using Polyelectrolytes as Promising Alternative to Fibre Beating
Stephan Daus (PTS)Trabzon, Octobre 8th 2013
04/21/23
2
Paper StrengthFibre Modification Concepts
PulpCation. Polyel-ectrolyt
Filtrate 2Filtrate 1
Pulp 2nd layerPulp 1st layer
Anion. Polyel-ectrolyt
PulpPulp
Cation. Polyel-ectrolyt
PulpCation. Polyel-ectrolyt
Filtrate 2Filtrate 2Filtrate 1Filtrate 1
Pulp 2nd layerPulp 1st layer
Anion. Polyel-ectrolyt
Pulp Anion. Polyel-ectrolyt
Pulp
Polyelectrolyte Modification (PEM):
• Fibre beating common method to increase paper strength
Increased density after beating – Loss of Bending Stiffness
High Energy Consumption
Alternative Methods Desired
04/21/23
3
Fibre Modification Concepts
1
2
3
45 6
7
8
9
1 10
2
3
45 6
7
8
9
1 1
anionic PEcationicPE
Pump Pump
PEC
Sheet formation
pulp
Modification with Polyelectrolyt Complexes
04/21/23
4
Uptake of Polyelectrolytes and Polyelectrolyte Complexes
• Uptake up to 2 % per g pulp• Uptake of polyelectrolytes depends on fibre charge
PEM 1 / PEC 1 – cationic and anionic starchPEM 2 / PEC 2 – polyallylamin hydrochloride and polyacrylic acidPEM 3 / PEC 3 – polyamidoamine-epichlorhydrin resin and carboxymethyl cellulose
PAAE / CMC
PAH / PAA
Kat. / anionicStarch
PAAE/ CMC
PAH / PAA
Cat. / anionicStarch
1818
1.5 %1.5 %1.5 %10 %1.5 %10 % StockConsistency
PEM 1 PEM 2 PEM 3 PEC 1 PEC 2 PEC 3
[mg/g] [mg/g] [mg/g] [mg/g] [mg/g] [mg/g]
BEKP 14.6 / 27.6 35 / 35 15 / 15 21
NBSK 9.7 / 18.4 30 / 30 10 / 5.1 21 18 18
PAAE / CMC
PAH / PAA
Kat. / anionicStarch
PAAE/ CMC
PAH / PAA
Cat. / anionicStarch
1818
1.5 %1.5 %1.5 %10 %1.5 %10 % StockConsistency
PEM 1 PEM 2 PEM 3 PEC 1 PEC 2 PEC 3
[mg/g] [mg/g] [mg/g] [mg/g] [mg/g] [mg/g]
BEKP 14.6 / 27.6 35 / 35 15 / 15 21
NBSK 9.7 / 18.4 30 / 30 10 / 5.1 21 18 18
04/21/23
5
Increase of the Tensile Index after Polyelectrolyte Modification
BEKP NBSK
0 20 40 60 80 100 120 140 160 1800
20
40
60
80
refined pulp
Ten
sile
ind
ex [
Nm
/g]
Refining energie [kWh/t]
0 20 40 60 80 100
0
20
40
60
80
Ten
sile
ind
ex [
Nm
/g]
Mass PEC/pulp [mg/g]
PEC3 PEC1
PEM3
PEM1
0 20 40 60 80 100 120 140 1600
20
40
60
80
refined pulp
Ten
sile
ind
ex [
Nm
/g]
Refining energie [kWh/t]
0 20 40 60 80 100
0
20
40
60
80
PEC3
PEC1PEM3
PEM1
Ten
sile
ind
ex [
Nm
/g]
Mass PEC/pulp [mg/g]
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6
Strength vs. Fibre Density
KF_150 kWh/t
KF_100 kWh/t
KF02
LF_180 kWh/t
LF_150 kWh/t
LF0
0
10
20
30
40
50
60
70
0,50 0,55 0,60 0,65 0,70
Rohdichte [g/cm3]
Te
nsi
le-I
nd
ex
[Nm
/g]
Mahlung KFKF_PEM1KF_PEM2KF_PEM3Mahlung LFLF_PEM1LF_PEM2LF_PEM3
PEM-Beschichtung
• reduced density after polyelectrolyte modification• increased paper strength
Density [g/cm³]
Ten
sile
Ind
ex [
Nm
/g]
04/21/23
7
y = 0.4307x + 1.3916
R2 = 0.9944
02468
101214161820
0 10 20 30 40 50Surface Charge [µeq/g]
Cat
. S
tarc
h [
mg
/g p
ulp
]
Increase of Polyelectrolyte Uptake
29242962.2CMC-treatedBSKP
6.77.06.013.4UnbeatenFine reduced
BSKP
CMC-treated
Unbeaten
Fine reduced
No
No
Pulp treatment
BHKP
BHKP
BHKP
BSKP
Pulp
14.5111432.1
119.510.522.7
29172964.3
9.68.89.419.6
3 (CS)2 (AS)1 (CS)[µeq/g]
PE-Modification (mg/g) Surface Charge
29242962.2CMC-treatedBSKP
6.77.06.013.4UnbeatenFine reduced
BSKP
CMC-treated
Unbeaten
Fine reduced
No
No
Pulp treatment
BHKP
BHKP
BHKP
BSKP
Pulp
14.5111432.1
119.510.522.7
29172964.3
9.68.89.419.6
3 (CS)2 (AS)1 (CS)[µeq/g]
PE-Modification (mg/g) Surface Charge
Polyelectrolyte Uptake:• is charge dependant• can be increased CMC grafting
04/21/23
8
Increase of the Storage Modulus after Polyelectrolyt Modification
0.0 1.0 2.0 3.0 4.0 5.0
BSKP - unbeaten
BSKP - unbeaten + PEM
BSKP - 50 kWh/t
BSKP - unbeaten + CMC + PEM + NFC
BSKP - 100 kWh/t
BSKP + 100 kWh/t + PEM
BSKP - unbeaten + CMC + PEM
Storage Modulus E' (GPa)
BeatingPolyelectrolytesPEM + Beating
04/21/23
9
Contact information:
• Dr. Stephan Daus, stephan.daus@ptspaper.de
• Dr. Nikita Polikarpov, nikita.polikarpov@ptspaper.de
Thank you for Listening.