Primary Wood Processing: Principles and PracticeSpringer Science & Business Media, 13 sep 2006 - 596 pagina's Samuel Johnson (of Boswell fame) said about writing, ‘whatever is written without effort is in general read without pleasure’ and ‘the unexamined word is not worth reading.’ However, even the most thoughtfully written text is unlikely to be described as a good read. This book is not an exhaustive review. Rather it is an uneven selection of examples whose interplay across disciplines hopefully illuminates what drives the practice of forest production, wood processing and consumer preferences. The choice of material is arbitrary reflecting personal biases. It is a summary of material presented to students at the NZ School of Forestry at the University of Canterbury. This book takes liberties with other peoples’ ideas, weaving them into fresh themes that are at best a work in progress. The philosopher Francis Bacon argued that ‘science is a debate in progress not a body of knowledge’ and also ‘truth emerges more readily from error than confusion’. We have taken the position that it is preferable to venture a reasoned opinion and be proved wrong than to waffle; so don’t swallow every sentence – ‘doubt everything’. The reader’s task is to unravel the conceits of generalizing and the risks of particularizing. |
Inhoudsopgave
23 | |
The Cellulose Microfibril and Cellulose Biosynthesis | 30 |
The Structure of Lignin | 43 |
The Cell Wall Structure of a Softwood Tracheid | 52 |
Wood Extractives | 64 |
DIMENSIONAL INSTABILITY IN TIMBER | 95 |
IN CONTEXT | 121 |
Industry Requirements | 124 |
PLYWOOD AND VENEERBASED PRODUCTS 1 Introduction | 391 |
Trends | 392 |
Plywood | 394 |
Raw Material Requirements | 396 |
Plywood Manufacture | 398 |
Competition and Technological Change | 416 |
Sliced Veneer | 418 |
TimberLike Products | 420 |
Spatial Distribution Within Trees | 125 |
Density | 128 |
Size Compression Wood and Knots | 142 |
Softwood Plantation Silviculture | 144 |
Eucalyptus for Wood Production | 155 |
MULTIFACETED OPPORTUNITIES 1 Introduction | 159 |
Stiffness | 160 |
Microfibril Angle | 166 |
Breeding for Increased Stiffness | 172 |
Acoustics to Select for Stiffness | 175 |
Near Infrared to Predict Wood Quality | 178 |
Strength and Adsorption of Energy | 179 |
Fibre Length | 180 |
Spiral Grain | 183 |
Heartwood | 186 |
Growth Stress and Reaction Wood | 187 |
Endgame | 202 |
SAWMILLING 1 Introduction | 203 |
Basic Saw Types and Blades | 204 |
Mill Design | 217 |
Mill Efficiency | 237 |
Aspects of Optimizing Sawlog Breakdown | 238 |
Flexibility | 250 |
DRYING OF TIMBER 1 Introduction | 251 |
The Drying Elements | 252 |
Surface Temperature | 254 |
The Movement of Fluids through Wood | 256 |
The External Drying Environment | 268 |
Drying Methods | 272 |
A Conventional Kiln Schedule | 281 |
HighTemperature Drying above 100oC | 285 |
Drying Degrade | 286 |
Practical Implications of Drying Models | 293 |
WOOD PRESERVATION 1 Introduction | 297 |
Organisms that Degrade Wood | 298 |
Natural Durability | 304 |
Philosophy of Protection | 306 |
Preservative Formulations | 308 |
Treatment Processes | 319 |
Health and Environmental Issues | 334 |
GRADING TIMBER AND GLUED STRUCTURAL MEMBERS 1 Introduction | 339 |
Theoretical Strength of Wood | 340 |
Timber Grading for NonStructural Purposes | 341 |
Visual Grading of Structural Lumber | 357 |
MachineGraded Structural Timber | 371 |
Adjusting Structural Timber Properties for Design Use | 378 |
Glued Structural Members | 380 |
Fire | 389 |
Timber Structures | 390 |
PARTICLEBOARD FIBREBOARDS AND ORIENTED STRAND BOARD 1 Introduction | 427 |
Market | 428 |
Characterising WoodBased Panels | 431 |
History of WoodBased Composites | 435 |
Raw Materials | 436 |
Generalised Panel Production Line | 439 |
Product Standards and Panel Performance | 468 |
Conclusion | 474 |
PULP AND PAPER MANUFACTURE 1 Introduction | 477 |
An Overview of Processing Options | 480 |
Paper | 481 |
Wood Preparation | 484 |
Mechanical Pulping | 485 |
Cleaning Washing and Screening | 491 |
Bleaching Mechanical Pulps | 492 |
Semichemical Pulping | 493 |
Chemical Pulping | 494 |
Sulphite Pulping Processes | 498 |
Sulphite Pulping Technology | 500 |
Chemical Recovery of Sulphite Liquors | 501 |
Process Chemistry and Alkaline Delignification Mechanisms | 502 |
The Kraft Pulping Process | 504 |
Extended Kraft Delignification | 508 |
The Kraft Recovery Cycle | 510 |
ByProducts of Softwood Pulping | 514 |
Bleaching of Chemical Pulps | 515 |
Effluent Loads and Disposal | 518 |
The Manufacture of Paper | 519 |
Beating of Chemical Pulps | 520 |
Papermaking | 524 |
Cylinder Machines for Paperboards | 530 |
Fibre Characteristics | 531 |
Some Definitions and Test Methods | 532 |
A HIDDEN GOLIATH 1 Introduction | 535 |
Characteristics of Wood as a Fuel | 538 |
Charcoal | 539 |
Fast Pyrolysis of Wood | 541 |
Wood as a Feedstock for Liquid Fuels | 545 |
Methanol Production | 547 |
Ethanol Production From Synthesis Gas | 548 |
Hydrolysis of Wood | 549 |
Ethanol Production by Acid Hydrolysis and Fermentation | 551 |
Ethanol via Simultaneous Saccharification and Fermentation | 553 |
Liquid Fuels | 554 |
Energy and Climate Change | 555 |
REFERENCES | 557 |
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Overige edities - Alles bekijken
Veelvoorkomende woorden en zinsdelen
achieved acid adhesive adsorbed water basic density bleaching boards carbon cell wall cellulose chemical pulps chips clearwood compression wood corewood delignification developed diameter diffusion Douglas fir dried dryer drying earlywood energy ethanol eucalypts evaporation extractives fibre saturation point Figure grade grain growth stresses hardwoods heartwood heat hemicelluloses humidity hydrogen bonding hydroxyl increase kerf kiln knots kraft latewood layer length less lignin liquor load longitudinal lower lumber manufacture material mechanical pulps microfibril angle microfibrils mill moisture content molecules outerwood oven-dry panel particleboard particles permeable Pinus radiata plywood polymer preservative pressure properties radial radiata pine ratio reaction wood reduced residual resin result sapwood sawn shrinkage softwoods species stack steam stem stiffness strand strength structural surface temperature tensile tension wood thickness timber tracheids treated wood treatment trees veneer volume width wood quality