From Forest To Product:

Transcription

1 From Forest To Product: New Solutions For Rapid, Comprehensive Wood And Fibre Analyses Co-authors: Kathy Woo, Ho Fan Jang, Shannon Huntley, James Drummond, Val Lawrence (Paprican) Francides Gomes, University of São Paulo

2 Outline The importance of fibre quality The measurement tools and applications: SilviScan HiRes Fibre Quality Analyzer Environmental Scanning Electron Microscope Confocal and Multiphoton Microscopy Concluding remarks

3 Wood properties impact both production efficiencies and product performance: Production costs: Growth rate Density Moisture Lignin content Extractives Brightness Uniformity Performance: Density Fiber length Fiber width Cell wall thickness Microfibril angle (MFA) Uniformity

4 The opportunities: Fibres from natural forests, such as boreal softwoods and North American hardwoods: Diverse range of species that allow pulps to be tailored to meet specific end-use requirements Need to understand and manage that diversity Plantation based forests, such as eucalyptus and hybrid poplars: Benefit from fast rotation, genetic improvements, forest management techniques Need to match genetic material to specific regions and growth conditions Quantify the impact of silvicultural practices on forest productivity and fibre quality

5 Need tools to efficiently measure wood and fibre quality attributes EvaluTree: State-of-the-art wood and fibre analysis centre A Canadian investment by: Government of Canada Government of British Columbia Pulp and Paper Research Institute of Canada

6 Wood and fibre analysis capabilities Core Samples Collected Microscopy Analysis Environmental Scanning Electron Microscopy Confocal Scanning Laser Microscopy Chemical Properties NIR and Raman Spectroscopy Wet Chemistry (IC / GCMS) Physical Properties SilviScan Fibre Quality Analyzer High Throughput Screening Tree Selection for Pulping Trials

7 Fibre and sheet structure analyses Fibre rising during printing (cross section) Fibres, handsheets, products Confocal Scanning Laser Microscopy Environmental Scanning Electron Microscopy Nanocrystalline cellulose Fibre Quality Analyzer Automated flow-through fibre analyzer uniquely configured for multiple sample assessments: Fibre length Fibre width Fibre coarseness Fibre shape

8 SilviScan Developed by researchers at CSIRO, Australia Installed January 2007 in North America (3 rd in world) Provides a rapid assessment of wood and fibre properties on a wood core (pith to bark) Determines: wood density microfibril angle (MFA) cell dimensions (radial and tangential) earlywood/latewood ratios fibre coarseness specific surface area

9 How SilviScan works Consists of three separate units: Optical microscopy / image analysis X-ray densitometer X-ray diffractometer Imaging microscope Bark Detectors X-ray source Pith 7mm Translation 2mm Rotation Schematic diagram of SilviScan s experimental design Measurements are made along the radial plane of a wood strip 2mm wide (tangential), 7mm high (longitudinal), and up to 300mm in length.

10 MFA (deg) Conditioned density (kg/m3) Tangential Fibre diameter (um) Radial Fibre diameter (um) Data generated Directly measured properties 10 0 o Fibre diameter (tangential and radial) o Fibre wall thickness 40 o Density o Microfibril angle 0.1mm-5mm resolution Calculated properties 1000 o Fibre coarseness 500 0o Specific surface o Wood stiffness µm resolution

11 Application of SilviScan: Impact of mountain pine beetle on pulp quality Over 582 million m 3 of lodgepole pine, on 9.2 million ha, infested with mountain pine beetle (Feb 2007) Increased pine content from 65 to 90% in spruce-pinefir chip mixtures due to increased salvage harvesting Need to understand impact on pulp quality

12 Average fibre diameter [microns] Impact of species and site on fibre diameter (annual rings from years) Spruce Pine Fir SPF-1 SPF-2 SPF-3 SPF-4 SPF-6 Forest sites infected by mountain pine beetle

13 Other examples Effects of fertilization on wood production Norway spruce plantations (STFI) Impact of thinning and fertilization on radiata pine microfibril angle (Australia) Broad and low peaks mean high MFA

14 HiRes Fibre Quality Analyzer Fibre length measurement on dilute fibre suspensions from macerated cores or pulp Measures fibre width, curl, kink AutoFeed handles up to 99 samples automatically

15 Hardwood fibre width distributions FQA Fibre width, microns E. grandis x E. urophylla - Brazil E. globulus - Portugal E. grandis x E. urophylla - Brazil Betula pendula - Finland E. grandis x E. urophylla - Brazil

16 Field-Emission Environmental SEM Capabilities dynamic experiments movie recording live web broadcast capability FEI Quanta-FEG 400 ESEM 2nm resolution in high vacuum pressures up to 20Torr image biological samples without coating (non-destructive) allows imaging of liquid water allows moisture cycling cooling stage (ambient to -20C) heating stage (up to 1000C) tensile stage X-ray spectrometer

17 Moisture in wood - ESEM

18 Moisture cycling - ESEM

19 Micro tensile stage inside chamber

20 Elemental composition and mapping by energy dispersive X-ray spectroscopy Image Oxygen map Sulfur map Calcium map

21 Confocal and Multiphoton Microscopes Carl Zeiss LSM 510 META NLO Upright microscope Laser module Scanning module Inverted microscope Multiphoton laser

22 From Spot to Image Plane Optical sectioning of objects without physical contact Z-Drive X/Y/Z Stack Information collection only out of one single plane Three dimensional reconstruction of the collected sections Three dimensional measurement

23 Acquire Image Stack

24 Applications: 3-D Wood Morphology Aspen Vessel Pitting

25 3D sheet structure Hybrid of E. grandis x E. urophylla - Brazil

26 Long wavelength Paper with ink Ink LP 560 nm Paper Short wavelength BP nm Ex 488 nm

27 Paper Structure Characterization by Image Analysis from Confocal Images ORIGINAL IMAGE: Hybrid of E. grandis x E. urophylla zoom0,7_5images_photomerge AFTER CONVERSION INTO GREY LEVELS (8 bit)

28 Next Steps: 1) Thresholding: Very simple due to the large contrast between the fibres and the background. 2) Grid: Generated for each image because the width and the height varied from image to image. The spacing can be adjusted according to the needed measurement resolution.

29 Characterization of Paper Structure Parameters Local Fiber Thickness Distribution Local Pore Thickness Distribution Top and Bottom Paper Profiles

30 Structural Paper Parameters Demonstration results from image analysis: Hybrid of E. grandis x E. urophylla zoom0,7: (1 µm Grid interval) Sample Average Fibre Mass Thickness (µm) Average Pore Thickness (µm) Average Local Paper Thickness (µm) Average Local Porosity (%) Top Roughness (µm) Bottom Roughness (µm) 3a 50.4 ± ± ± ± Demonstration only To have reliable results of paper structure, longer samples should be analyzed.

31 Concluding remarks New developments in optical-based, rapid assessment techniques make it easier that ever to conduct high-throughput wood and fibre quality evaluations on statistically significant sample sets In many cases the testing can be conducted on wood cores extracted from standing trees, eliminating the need to destructively sample Applications extend to paper structure, helping to quantify the links between fibre quality and end-use performance. from forest to product

32 Acknowledgements Thanks to co-author Francides Gomes, University of São Paulo, for collaboration on comparison of world hardwoods Thanks to Paprican co-authors: Kathy Woo, Ho Fan Jang, Shannon Huntley, James Drummond, Val Lawrence