- •Recovered Paper and Recycled Fibers
- •Isbn: 3-527-30999-3
- •Introduction
- •Isbn: 3-527-30999-3
- •Isbn: 3-527-30999-3
- •2006, Isbn 3-527-30997-7
- •Volume 1
- •Isbn: 3-527-30999-3
- •4.1 Introduction 109
- •4.2.5.1 Introduction 185
- •4.3.1 Introduction 392
- •5.1 Introduction 511
- •6.1 Introduction 561
- •6.2.1 Introduction 563
- •6.4.1 Introduction 579
- •Volume 2
- •7.3.1 Introduction 628
- •7.4.1 Introduction 734
- •7.5.1 Introduction 777
- •7.6.1 Introduction 849
- •7.10.1 Introduction 887
- •8.1 Introduction 933
- •1 Introduction 1071
- •5 Processing of Mechanical Pulp and Reject Handling: Screening and
- •1 Introduction 1149
- •Isbn: 3-527-30999-3
- •Isbn: 3-527-30999-3
- •Isbn: 3-527-30999-3
- •Isbn: 3-527-30999-3
- •Introduction
- •Introduction
- •Isbn: 3-527-30999-3
- •1 Introduction
- •1 Introduction
- •1 Introduction
- •1 Introduction
- •1 Introduction
- •1 Introduction
- •150.000 Annual Fiber Flow[kt]
- •1 Introduction
- •1 Introduction
- •Introduction
- •Isbn: 3-527-30999-3
- •Void volume
- •Void volume fraction
- •Xylan and Fiber Morphology
- •Initial bulk residual
- •4.2.5.1 Introduction
- •In (Ai) Model concept Reference
- •Initial value
- •Validation and Application of the Kinetic Model
- •Inititial
- •Viscosity
- •Influence on Bleachability
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Impregnation
- •Introduction
- •International
- •Impregnation
- •Influence of Substituents on the Rate of Hydrolysis
- •140 116 Total so2
- •Xylonic
- •Viscosity Brightness
- •Xyl Man Glu Ara Furf hoAc XyLa
- •Initial NaOh charge [% of total charge]:
- •Introduction
- •Isbn: 3-527-30999-3
- •Introduction
- •Isbn: 3-527-30999-3
- •Introduction
- •Introduction
- •Isbn: 3-527-30999-3
- •In 1950, about 50% of the global paper production was produced. This proportion
- •4.0% Worldwide; 4.2% for the cepi countries; and 4.8% for Germany.
- •1150 1 Introduction
- •1 Introduction
- •1 Introduction
- •Virgin fibers
- •74.4 % Mixed grades
- •Indonesia
- •Virgin fibers
- •Inhomogeneous sample Homogeneous sample
- •Variance of sampling Variance of measurement
- •1.Quartile
- •3.Quartile
- •Insoluble
- •Insoluble
- •Insoluble
- •Integral
- •In Newtonion liquid
- •Velocity
- •Increasing dp
- •2Α filter
- •0 Reaction time
- •Increasing interaction of probe and cellulose
- •Increasing hydrodynamic size
- •Vessel cell of beech
- •Initial elastic range
- •Internal flow
- •Intact structure
- •Viscosity 457
- •Isbn: 3-527-30999-3
- •1292 Index
- •Visbatch® pulp 354
- •Index 1293
- •1294 Index
- •Impregnation 153
- •Viscosity–extinction 433
- •Index 1295
- •1296 Index
- •Index 1297
- •Inhibitor 789
- •1298 Index
- •Index 1299
- •Impregnation liquor 290–293
- •1300 Index
- •Industries
- •Index 1301
- •1302 Index
- •Index 1303
- •Xylose 463
- •1304 Index
- •Index 1305
- •1306 Index
- •Index 1307
- •1308 Index
- •In conventional kraft cooking 232
- •Visbatch® pulp 358
- •Index 1309
- •In prehydrolysis-kraft process 351
- •Visbatch® cook 349–350
- •1310 Index
- •Index 1311
- •1312 Index
- •Viscosity 456
- •Index 1313
- •Viscosity 459
- •Interactions 327
- •1314 Index
- •Index 1315
- •Viscosity 459
- •1316 Index
- •Index 1317
- •Xylose 461
- •Index 1319
- •Visbatch® pulp 355
- •Impregnation 151–158
- •1320 Index
- •Index 1321
- •1322 Index
- •Xylan water prehydrolysis 333
- •Index 1323
- •1324 Index
- •Viscosity 459
- •Index 1325
- •Xylose 940
- •1326 Index
- •Index 1327
- •In selected kinetics model 228–229
- •4OMeGlcA 940
- •1328 Index
- •Index 1329
- •Intermediate molecule 164–165
- •1330 Index
- •Viscosity 456
- •Index 1331
- •1332 Index
- •Impregnation liquor 290–293
- •Index 1333
- •1334 Index
- •Index 1335
- •1336 Index
- •Impregnation 153
- •Index 1337
- •1338 Index
- •Viscose process 7
- •Index 1339
- •Volumetric reject ratio 590
- •1340 Index
- •Index 1341
- •1342 Index
- •Index 1343
- •1344 Index
- •Index 1345
- •Initiator 788
- •Xylose 463
- •1346 Index
- •Index 1347
- •Vessel 385
- •Index 1349
- •1350 Index
- •Xylan 834
- •1352 Index
4.1 Introduction 109
4.2 Kraft Pulping Processes 111
4.2.1 General Description 111
4.2.2 Kraft Cooking Liquors 113
Contents
IX
4.2.3 Mass Transfer in Kraft Cooking 122
4.2.3.1 Purpose of Impregnation 122
4.2.3.2 Heterogeneity of Wood Structure 123
4.2.3.3 Steaming 130
4.2.3.4 Penetration 133
4.2.3.5 Diffusion 138
4.2.3.6 Diffusion Model 151
4.2.3.7 Effect of Impregnation on the Uniformity of Delignification 159
4.2.3.8 Numerical Solution of the Diffusion Model 163
4.2.4 Chemistry of Kraft Cooking 164
Antje Potthast
4.2.4.1 Lignin Reactions 164
4.2.4.2 Reactions of Carbohydrates 174
4.2.4.3 Reactions of Extractives 181
4.2.4.4 An Overview of Reactions During Kraft Pulping 183
4.2.4.5 Inorganic Reactions 184
4.2.5 Kraft Pulping Kinetics 185
Herbert Sixta
4.2.5.1 Introduction 185
4.2.5.2 Review of Kraft Cooking Models 188
4.2.5.3 Structure of a Selected Kinetic Model for Kraft Pulping 211
4.2.6 Process Chemistry of Kraft Cooking 229
4.2.6.1 Standard Batch Cooking Process 229
4.2.6.2 Modified Kraft Cooking 235
4.2.6.3 Polysulfide and Anthraquinone Pulping 306
4.2.7 Multistage Kraft Pulping 325
4.2.7.1 Prehydrolysis 325
4.2.7.2 Prehydrolysis: Kraft Pulping 345
4.2.8 Pulping Technology and Equipment 366
Andreas W. Krotschek
4.2.8.1 Batch Cooking versus Continuous Cooking 366
4.2.8.2 Batch Cooking Technology and Equipment 367
4.2.8.3 Continuous Cooking Technology and Equipment 377
4.3 Sulfite Chemical Pulping 392
Herbert Sixta
4.3.1 Introduction 392
4.3.2 Cooking Chemicals and Equilibria 395
4.3.3 Impregnation 403
4.3.4 Chemistry of (Acid) Sulfite Cooking 405
Antje Potthast
4.3.4.1 Reactions of Lignin 407
4.3.4.2 Reactions of Carbohydrates: Acid Hydrolysis 416
4.3.4.3 Reactions of Extractives 425
4.3.5 Process Chemistry of Acid Sulfite Pulping 427
Herbert Sixta
Contents
4.3.5.1 Basic Technology 427
4.3.5.2 Influence of Reaction Conditions 449
4.3.6 Alternative Sulfite Pulping Concepts 465
4.3.6.1 Magnefite Process 466
4.3.6.2 Two-Stage Neutral Magnefite (Bisulfite-MgO) 467
4.3.6.3 Sivola Processes 468
4.3.6.4 Stora Processes (Hydrogen Sulfite or Monosulfite-Acid Sulfite) 472
4.3.6.5 Alkaline Sulfite Pulping 475
5 Pulp Washing 511
Andreas W. Krotscheck
5.1 Introduction 511
5.2 Pulp Washing Theory 512
5.2.1 Overview 512
5.2.2 Drainage 513
5.2.3 Compressive Dewatering 517
5.2.4 Diffusion 517
5.2.5 Sorption 519
5.3 Principles of Washing 523
5.3.1 Dilution/Extraction Washing 524
5.3.2 Displacement Washing 524
5.3.3 Compressive Dewatering 525
5.3.4 Multi-Stage Washing 526
5.3.5 Fractional Washing 528
5.4 Washing Parameters 528
5.4.1 Overview 528
5.4.2 Dilution Factor 529
5.4.3 Feed and Discharge Consistencies 532
5.4.4 pH 533
5.4.5 Entrainment of Air 534
5.4.6 Temperature 535
5.4.7 Equipment-Specific Parameters 535
5.5 Washing Efficiency 537
5.5.1 Overview 537
5.5.2 Wash Yield 537
5.5.3 Displacement Ratio 538
5.5.4 Norden Efficiency Factor 539
5.5.5 Standardized Norden Efficiency Factor 545
5.6 Washing Equipment 547
5.6.1 General Remarks 547
5.6.2 Rotary Drum Washers 547
5.6.2.1 Conventional Drum Washers 547
5.6.2.2 Drum Displacer 549
5.6.3 Belt Washers 551
X Contents
5.6.4 Diffusion Washers 552
5.6.4.1 Atmospheric Diffuser 552
5.6.4.2 Pressure Diffuser 554
5.6.5 Roll Presses 556
5.6.6 In-Digester Washing 557
6 Pulp Screening, Cleaning, and Fractionation 561
Andreas W. Krotscheck