April 22, 2014

Biomaterial Science（Schedule）

EG60411

Bio-Material Science
Toshiharu Enomae

Professor, PhD, Paper Device and Eco-friendly materials

2G103, 10:10-11:25, Tuesday

Lecture information and contact#DateContent

1

4/15

History of papermaking

24/22

Pulps – Beating and fiber properties

35/9, Fri

Pulps – Additives and functions

45/13

Papermaking processes & interfiber bonding

55/20

Paper– Structural and absorption properties

65/27

Paper– Mechanical and optical properties

76/3

Polysaccharide chemistry by Assoc Prof Akiko Nakagawa

8-9

6/10, 17

Pulping science and technology by Professor Hiroshi Ohi

106/24

Recent trend of paper science and technology

Production of paper and paperboard
120

Homepage of “Biomaterial Science (T.
Enomae)”E-mail address→ t@enomae.com
for any questions and visit to laboratory(Bio-Agr. Bldg. 生農C209 or E201)

100

Production , million ton

http://www.enomae.com/→ Handouts in lecture(講義資料)

China
(A2)
USAJapan(A3)
Germany
Sweden
Korea
CanadaFinland
BrazilIndonesia
India
Thailand8060
402001999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012

How to make paper

From “wood”

Wood tissue－cells of beech tree

ForestWaste(A4)paperWood(thinned out)

Component ofhardwood tissue
Vessel20%
Wood fiber

60％

Axial
10％
parenchyma cell
Radial10％
parenchyma cell

Chip
Pulp

Paper

Biomaterial Science by Toshiharu Enomae

1April 22, 2014

Wood tissue－structure of cell wall

Axial parenchyma cellS3 layer

Bright-field

Polarized light(Secondary cell wall - 3rd layer )Cellulose microfibril

S2 layer(indicated by parallel lines)

S1 layerPrimary wall
Middle lamella

Bast fibers

parenchyma cells

0.1 mm
Structure of plant cell wall and axial direction of cellulose microfibrils

Kind of pulp

Chemical pulp－Fiber geometry
Softwood pulp fiber

Pulp

Hardwood pulp fiber

Fibers mainly consisting of cellulose
extracted from plant such as wood bymechanical or chemical treatment

Mechanical pulp [MP]Fibers extracted from wood by crushing

Chemical pulp [CP]Copy paper

Fibers extracted from wood by dissolving lignin

consists ofpulp fibers

Deinked pulp [DIP] (recycled pulp)
Fibers extracted from waste paper by removing ink

Wood composition－Major 3 components
Chemicalcomponent

Approx. ratio (%)

Hardwood

Softwood Hardwood

Cellulose

Cellulose

4545

Hemicellulose

2530

Lignin2520

OthersTerpenoid
Resin acid
Fatty acidetc.

wood

Observe pulps

Form of pulp

Bleached
kraft pulp
40 %

45 %

Hemicellulose
30 %Lignin2-8(B)

20 %

10 %
2%

Bale pulp
A bunch of pulp sheets
compressed and boundwith a wire

Others5%

Change of Compositionby kraft pulping

Biomaterial Science by Toshiharu Enomae

Dry lap pulp

Slush pulp
Pulp suspension withconcentrations of approx.
1-4%
Lap pulp
Pulp Formed and folded bywet machine. Called “Drylap” when dried

Transported (C) pulp

2April 22, 2014

Disintegration - Separation into individual fibers

Standard disintegrator (defibrator)
Pulp is put in water in steel
container with ca. 3.4 L capacity

Dry lap pulp

Stirred with a propeller mixer at
3000 min-1（rpm）

Dispersed in water ( (D) pulp)

Latency of MP should beremoved at high temperature（Latent=hidden）
Pulp
ChemicalDry Water Revolmass volume utions
30 g
2.0 L 30,000

Mechanical

60 g

2.7 L

60,000Waste paper in yard

Waste paper and pulp

Belt conveyer

Disintegration in industry (pulper)

Biomaterial Science by Toshiharu Enomae3

April 22, 2014

Disintegration in industry (Drum pulper)

Floatation
Deinking
Postflowtation

Disperser

Centrifugal

Bleaching
Peroxidetower

Post-flowtator
Drum pulper

Floatation (flowtator)

Beating (refining)
Post-disintegration process
Process where shear stress is applied
to water-containing fibers resulting infibrillation (formation of small
filaments or fibers) on the surface
and concentrically loose structure

Beating (refining)
Beating achieves large bonded area
between fibers and thus higher paper
strength.

Difference between disintegration and beating

Disintegration is a process toseparate fibers bonded orentangled, keeping fiber
characteristics
Beating is a process to treat
mechanically individual fibers,changing fiber characteristics

Q. Why can this breaking process increase paper strength?

Biomaterial Science by Toshiharu Enomae

4April 22, 2014

Beater－PFI mill (beating)Beater－Refiner(refining)
Processed by refiner
Rotor

InOut

Motor
Blade
Disk plate
Stator

OutRotor
Pulp slurry flow Stator

Beating － mechanism

Refining－movie－refiner

Effect of blades on pulp fibers during beating

Beating－change of fibers－external fibrillation

Beating－change of fibers－internal fibrillation

External fibrillation

External fibrillation

Internal fibrillation

Internal fibrillation＝Concentric loosening(Lamellar separation)
Connection of small
pores formed by lignin
removalScanning Electron Micrographs of freeze-dried
softwood pulp fibers after beating

Biomaterial Science by Toshiharu Enomae

Lamellar separation offiber cell wall by beating5