Extrusion Processing Technology

About the authorsProfessor Jean-Marie Bouvier is Scientific Advisor at Clextral, Firminy, France. Professor Osvaldo H. Campanella is a Professor of Agricultural and Biological Engineering at the Whistler Carbohydrate Research Center, Purdue University, Indiana, USA.

• Foreword ixAcknowledgements xi1 Generic Extrusion Processes 11.1 A history of extrusion processing technology 11.1.1 The introduction of screw extruders 11.1.2 The generic extrusion process concept 21.1.3 Extrusion technology in the polymer-processing industry 31.1.4 Extrusion technology in the food- and feed-processing industry 41.1.5 Extrusion technology in the paper-milling industry 81.2 Factors driving the development of extrusion processing technology 91.2.1 Process productivity 91.2.2 Product innovation and functionality 91.2.3 Environmentally friendly processing 101.3 The industrial and economic importance of extrusion processing technology 101.3.1 In the polymer and plastics industry 101.3.2 In the food and feed industry 101.3.3 In the paper milling industry 111.4 Contents and structure of the book 11References 122 Extrusion Equipment 132.1 Extruders 132.1.1 The kinematics of extruders 132.1.2 The screw-barrel assembly 152.1.3 The die assembly 202.1.4 The central operating cabinet 282.2 Extruder screw-barrel configurations 282.2.1 Single screw extruders 292.2.2 Intermeshing co-rotating twin screw extruders 312.2.3 Screw-barrel configuration and wear 332.3 Ancillary equipment 392.3.1 Upstream ancillary equipment 402.3.2 On-line ancillary equipment 442.3.3 Downstream ancillary equipment 46References 513 Extrusion Engineering 533.1 Thermomechanical processing in screw extruders 533.1.1 Process configuration of single screw extruders 533.1.2 Process configuration of intermeshing co-rotating twin screw extruders 553.1.3 Processing specificities 563.2 Thermomechanical flow in screw extruders 583.2.1 Modeling approaches 583.2.2 Solids conveying section 673.2.3 Melt conveying section 723.2.4 Single screw extrusion versus twin screw extrusion 1103.3 Thermomechanical extrusion processing: use of numerical methods 1153.3.1 Single screw extrusion 1153.3.2 Twin screw extrusion 1183.3.3 Commercial software 120References 1224 The Generic Extrusion Process I: Thermomechanical Plasticating of Polymers and Polymer Melt Forming 1254.1 The bio-based polymers and bio-based plastics 1264.1.1 Definitions 1264.1.2 Macromolecular characteristics of bio-based polymers 1294.2 Melting mechanism of polymer materials in screw extruders 1384.2.1 Melting mechanism in single screw extruders: qualitative description 1394.2.2 Engineering analysis of polymer melting in single screw extruders 1404.2.3 Melting mechanism in intermeshing co-rotating twin screw extruders 1434.2.4 Polymer melting: single screw extrusion versus twin screw extrusion 1464.3 Physical transitions of bio-based polymers 1474.3.1 Physical transitions of polymeric materials: generalities 1474.3.2 Glass and melting transitions: basics 1494.3.3 Glass and melting transitions of bio-based polymers 1514.4 Flow properties of bio-based polymer melts 1574.4.1 Flow behavior: basics 1574.4.2 Measurement of flow properties of polymer melts 1594.4.3 Rheological characteristics of bio-based polymer melts 1614.5 Case studies: emerging applications 1624.5.1 Melting of polyamide-11 in a single screw extruder: exercise 1624.5.2 Extrusion processing of biodegradable starch-based loose-fill packaging foams 1634.5.3 Extrusion compounding of flax fiber-reinforced thermoplastics 165References 1685 The Generic Extrusion Process II: Thermomechanical Micromixing and Reactive Extrusion 1735.1 Reactive extrusion: qualitative description 1745.1.1 Bulk polymerization 1745.1.2 Reactive processing of polymers. Reactive plastics reprocessing 1755.1.3 Reactive extrusion in classic organic chemistry 1775.1.4 Reactive solid-liquid extrusion-pressing 1785.1.5 Processing characteristics of reactive extrusion 1785.2 Reactive extrusion: chemical reaction engineering approach 1795.2.1 The continuous plug flow reactor 1815.2.2 Mixing in screw extruder-reactors 1895.2.3 Heat transfer mechanisms in extruder-reactors 2065.2.4 Coupling of transport phenomena and chemical reactions 2105.2.5 Basic principles of process engineering in reactive extrusion 2135.3 Reactive extrusion applications and processing lines 2155.3.1 The classes of chemical reactions in reactive extrusion 2155.3.2 Case study 1: casein-to-caseinate extrusion processing 2175.3.3 Case study 2: extrusion pulping of non-wood fibers 2205.3.4 Case study 3: enzymatic hydrolysis of starch 225References 2386 The Generic Extrusion Process III: Thermomechanical Cooking and Food Product Texturization 2436.1 Food extrusion-cooking: qualitative description 2446.1.1 Thermomechanical cooking of biopolymer-based systems 2446.1.2 Texturization of extrusion-cooked melts 2546.2 Engineering analysis of process functions 2556.2.1 Preconditioning 2556.2.2 Extrusion-cooking 2616.2.3 Steam-induced die texturization 2766.3 Examples of industrial applications: food extrusion processing lines 2936.3.1 Breakfast cereals extrusion processing 2946.3.2 Aquafeed extrusion-cooking process 3006.3.3 High-moisture extrusion-cooking process 304References 3067 Quality Analysis of Extrusion-Textured Food Products 3117.1 Methods of thermomechanical cooking analysis 3117.1.1 Optical microscopy for birefringence analysis 3127.1.2 Water solubility (WSI) and absorption (WAI) indices 3127.1.3 Alkaline viscosity 3137.1.4 Differential scanning calorimetry 3137.1.5 Rapid Visco™ Analyzer 3147.2 Methods of characterizing extrudate texture 3277.2.1 Measurement of product density 3277.2.2 Measurement of structural characteristics 3287.2.3 Measurement of mechanical characteristics 3347.2.4 Physical texture of directly expanded extrudates 3427.3 Case study: texture monitoring of directly expanded extrudates 3437.3.1 Main features of process–product relationships 3437.3.2 Methodology for texture monitoring 3447.3.3 Master correlations between sensory attributes and puncture parameter 346References 3488 The Generic Extrusion Process IV: Thermomechanical Pretreatment and Solid–Liquid Separation 3518.1 The fourth Generic Extrusion Process: continuous mechanical expression 3528.2 Engineering analysis of thermomechanical expression 3568.2.1 Structure of cellular biological materials 3578.2.2 Introduction of the nomenclature 3598.2.3 General description of the filtration and consolidation processes 3638.2.4 Rheological properties of cellular biological materials and their characterization 3678.3 Process modeling 3708.3.1 The fluid mechanics of the process and determination of relevant parameters 3708.3.2 Effects of material properties on the process yield 3758.3.3 Effects of processing conditions and screw geometry on pressure build-up and liquid expression 3788.4 Case studies: examples of industrial applications 3818.4.1 Continuous screw extrusion-pressing of copra, a hard cellular material 3828.4.2 Continuous screw extrusion-pressing of groundnuts/peanuts, a soft cellular material 3828.4.3 Soybean processing 3838.4.4 Feed pretreatments 386References 3909 The Generic Extrusion Process V: Thermophysical Micromixing and Material Porosification 3939.1 The new generic extrusion-porosification process 3959.1.1 Typical drying processes for instant powders 3959.1.2 Main drivers of instant powder drying 4179.1.3 The extrusion-porosification process 4219.2 Engineering discussion of process functions 4259.2.1 Vacuum evaporation 4269.2.2 Twin screw extrusion-aeration 4409.2.3 Intensified spray drying 4509.3 Perspectives on industrial applications 4519.3.1 Range of applications 4519.3.2 Case study: extrusion-porosification of dairy products 453References 45910 Extrusion Technology and Process Intensification 46510.1 From sustainable development to process intensification 46510.1.1 The IPAT equation 46610.1.2 Sustainable development 46710.1.3 Sustainable technology 46910.1.4 Concept of process intensification 47010.2 Process intensification in extrusion processing technology 47210.2.1 Characteristic times of process phenomena 47310.2.2 Process-intensifying methods in extrusion 47410.2.3 Sustainability of extrusion processing technology 49710.3 Case studies: exercises 49910.3.1 Exercise 1: Residence time distribution 49910.3.2 Exercise 2: Polymer melt coupling in reactive extrusion 50110.3.3 Exercise 3: Weighted average total strain 50210.3.4 Exercise 4: Energy saving in extrusion-cooking 50310.3.5 Exercise 5: Water saving in solid-liquid extrusion-pressing 50310.4 Conclusion: future trends 504References 505Index 507