vaahtorainauksen tutkimus vtt:n tutkimusympäristöissätwo major benefits compared to traditional...
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Vaahtorainauksen tutkimus VTT:n tutkimusympäristöissä
Metsäteollisuuspäivät Savonlinna 19.-20.9.2018
Harri Kiiskinen, VTT
[email protected]: +358 40 527 3853
18.09.2018 VTT – beyond the obvious 1
Foamed water – A disaster?
18.09.2018 VTT – beyond the obvious
Foamed water – A disaster? An opportunity
18.09.2018 VTT – beyond the obvious
Why foam technology Two major benefits compared to traditional papermaking
1) Formation – sheet uniformity. Practically always good
for all fibers Good formation with long fibers.
2) Possibility to highly porous structures a method for
raw-material efficiency & new fiber based products.
Widens the product property window
New product possibilities for wood fibres
• Insulation, filtering, absorbing, packaging, …
Material combinations
• Mixture of high & low density materials
Wiggins TeapeRadfoam
Piloting & small, full scale production machines
Oblivion / secrecy
New emergence
Preparing for commercialization
Entering production
Historical perspective on foam forming
70’s
80’s
90’s
2008
2015
2020
Foam forming is in industrial
use for specialty products
Fiber foam Multi-phase system
• Water, air, solid material
Fiber suspension + air
• Surface active agent
• Typical air content 40 – 70%
• Foam stability can be controlled
• Typical bubble diameter ~100 µm
No fiber flocculation
• Small bubbles fill the free space
There is no scientific literature related
to fibrous foams
Foam Generation
Simulations by Topi Kähärä, JyU
Experimental – Lab Studies
From Water-laid to Foam-laid Process
Piloting
Genera-tion of foam
On-line foam
measure-ments
Pumping of foam
Headbox
Vacuum system
Running concepts
VTT Foam Forming PilotsSAMPO• Pilot-scale research environment for non-
pressed materials
• Foam Forming Technology
• Vertical headbox
• Horizontal geometry
• Impingement and TAD dryers
• D=600 mm, max speed 200 m/min
• Start-up 2017
SUORA• Pilot-scale research environment for
papermaking board manufacturing processes
and product development
• Water-laid and Foam-laid webs
• Stratified foam forming
• Small amounts of raw material • <100 kg abs dry
• D=300 mm, max speed 2000 m/min
• Built 2006, rebuild 2010, foam start-up 2013
Aqueous cellulose-based foams
Average bubble size was shown to correlate
well with fiber foam stability (Salminen et al.
2014).
Bubble size distribution derives to the pore
structure of fiber network (Al-Quararah et al.
2015, Ketoja, ACS meeting 2016).
Density of fiber foam affects fiber network
strength, bulk, formation and dryness after
wet pressing (Torvinen et al.2015).
Flocculation tendency of fibers is
proportional to rr N (Kiiskinen et al. 2016).
18.09.2018 VTT – beyond the obvious
Low
density
foam
Water
Low
density
foam
Wate
r
High
density
foam
High
density
foam
Foam forming in the field of nonwovens
Air-laid- High porosity
- Limited strength
Foam forming
provides means
of handling long fibers in wet conditions
and to produce high porosity web
Str
ength
Porosity
100 kg/m3
300 kg/m3
Wet-laid- Strong webs- Limited fiber length- High densities
Compression strength and Recovery50% compression
70
75
80
85
90
95
100
0 10 20 30 40 50 60 70 80 90
Recovery
(aft
er
50 %
com
pre
ssio
n),
%
Density, kg/m3
CTMP +SDS
BSKP +SDS
EPS
0
20
40
60
80
100
120
140
160
180
200
0 10 20 30 40 50 60 70 80 90
Com
pre
ssio
n s
tre
ss (
50 %
com
pre
ssio
n),
kP
a
Density, kg/m3
CTMP +SDS
BSKP +SDS
EPS
Compression strength EN 826 standard (at 10% strain)
No strength additivesCTMP (Chemithermomechanical Pulp)
BSKP (Bleached Softwood Kraft Pulp)
SDS (Sodium Dodecyl Sulphate)
Lightweight,
mouldable boardReplacement for plastic
Growth mediaSound insulation Nonwovens
Packaging and cushioning
Construction
Foam forming as a manufacturing
platform for future fiber products
Technology Platform for Fibre Products
Towards increased value for fibre products
• Funding: European Regional Development Fund,
participating companies and VTT
• Budget 4.4 M€
• Duration 06/2017 - 05/2020
• 33 companies, coordinated by VTT
Contact: [email protected] [email protected]
