Advanced Process Engineering Control (De Gruyter) | Alexandra Ana Csavdari, Botond Szilagyi, and Paul S. Agachi

Advanced Process Engineering Control (De Gruyter)

by Alexandra Ana Csavdari, Botond Szilagyi, and Paul S. Agachi

Preface
The present work, Advanced Process Engineering Control, is intended to be the continuation of the authorsʼ Basic Process Engineering Control published by DeGruyter in 2014. It presents the main and conventional type control loops in process industries. Titles containing the concept of process engineering were deliberately chosen to suggest the inclusion, within the same approach, of processes other than the traditional ones. These come from outside the traditional fields of chemistry and petrochemistry: the sphere of pharmaceuticals, wastewater management, water purification, water reserve management, construction material industry, food processing, household or automotive industries.

During use and development of automatic control systems, control analysis and control system design for process industries have followed the traditional unit operation approach. It means that all control loops are established individually for each unit or piece of equipment in the plant and that the final plantwide control system represents the sum of the individual parts. The disadvantage of this method is the difficulty in stabilizing potential conflicts among individual loops. One very handy method of avoiding these interactions is the different tuning of control loops: those controlling the most important parameters are tuned tight and the others loose. Despite any process complexity, the unit operation approach provided reasonable results and remains in use on a large scale for designing control systems. Consequently, the book follows this traditional approach but provides updates to new industrial achievements.

Modern process plants are designed for flexible production and maximization of energy and material savings, especially within the frame of globalization and strong competition among manufacturers. Additionally, according to the fourth paradigm of process /chemical engineering, the processes have to fulfill tight environmental constraints. Industrial plants become more complex and have therefore strong interactions between process units. As a consequence, the failure of one unit might have a negative effect both on overall productivity and on environmental performances. This situation raises important control issues. A significant example is that of the thermally integrated plants, a concept born during the global energy crisis that started in 1973. Energy recovery became a priority for the industry and at the same time a scientific challenge. The necessity of redesigning industrial processes in terms of energetic efficiency was identified. Moreover, it was discovered that energy saving can be achieved using retrofit and recovery of extra energy from all secondary sources of a process. These aspects posed complex control problems because of the weak process controllability (effects of all disturbances are collected at the end of the process and reintroduced as enhanced disturbances at the input).

The emergence and continuous development of advanced control techniques provided solutions for plantwide control at any level of process complexity and in the above-mentioned conditions. According to Willis and Tham, a definition of the advanced process control can be formulated as “a systematically studied approach for the choice of pertinent techniques and their integration into a co-operative management and control system that will significantly enhance plant operation and profitability”.

Applied on complex chemical processes, advanced control is able to improve product yield, reduce energy consumption, increase plant capacity, improve product quality and consistency, enhance process safety, and reduce environmental impact. The benefits of the advanced control implementation are noticeable in the overall operating costs of a plant. These can decrease by 2% to 6%. Another benefit is the reduction of process variability. As a consequence, a plant can be operated at its designed capacity.

The present book is structured into two parts. Part I, entitled Advanced Process Control comprises chapters 1–7 and defines as advanced control any control system that surpasses simple and conventional loops. This could mean either smarter control configuration (cascade, feedforward, ratio, inferential, digital, or multivariable control) or improved regulator features (fuzzy, model predictive or optimal control). Approaches for the design of plantwide control systems are also presented. Part II, entitled Applied Process Engineering Control includes chapters 8–14 and refers to control solutions for the so-called unit operations: reaction and separation processes (distillation, absorption-desorption, extraction, evaporation, drying, and crystallization). The reader can check her or his level of comprehension by solving the problems and exercises proposed in Chapter 15. These cover the entire list of discussed topics. The authors hope that by including many industrial examples and applications as well as their own and other researcher’s experience accumulated over many years within the Group of Computer Aided Process Control, the present work will be useful for all interested parties in process engineering and process control: students in electrical, chemical, or process engineering; specialists in chemical, petrochemical or automation companies; professionals of water or natural gas management; etc.

The idea of this book series describing the main aspects of modern process engineering as applied to (not only) chemical industry belongs to Prof. Dr. Paul Şerban Agachi. He initiated the manuscripts, developed their structure, and coordinated the authors. More than 20 years ago, he recognized the ever-increasing importance of the subject and founded the Group of Computer Aided Process Engineering at the Faculty of Chemistry and Chemical Engineering of the Babeş-Bolyai University in Cluj-Napoca, Romania. Many professionals emerged from it, and the three younger authors of the present work have also started their carriers here. Although writers have exchanged ideas and discussed all topics of this book, work was distributed in agreement with individual strengths, experience, and competencies: Prof. Dr. Paul Şerban Agachi was in charge of chapters 1, 4, 12 and 13; Prof. Dr. Mircea Vasile Cristea shared his experience in chapters 2, 3, and 5–7; Assoc. Prof. Dr. Alexandra Csavdári wrote chapters 8 and 11, and coauthored with young Eng. Botond Szilágyi chapters 9, 10, and 14 with assistance from Ş. Agachi. The list of problems and exercises in Chapter 15 is the result of a joint effort. Finally, within the framework of this laborious enterprise, the authors gratefully acknowledge graduate students Maria Gherman, Abhilash Nair, Zsolt Tasnadi-Asztalos, Lászlo Zsolt Szabó and Hoa Pham Tai (engineers working in the Group of Computer Aided Process Engineering) for their dedicated and valuable help.

Contents

Preface v
Part I: Advanced Process Control 1
1 Complex and nonconventional control systems 3
1.1 Cascade control systems 3
1.1.1 Processes in series 3
1.1.2 Processes in parallel 10
1.2 Feedforward control systems 15
1.3 Ratio control systems 24
1.4 Inferential control systems 27
1.5 Selective control systems 28
References 30
2 Model predictive control 32
2.1 Introduction 32
2.2 MPC history 32
2.3 Basics of MPC control strategy 34
2.4 Types of MPC process models 42
2.4.1 Impulse and step response models 43
2.4.2 State-space models 49
2.4.3 Time series models 49
2.5 Predictions for MPC 50
2.6 Optimization for MPC 60
2.7 MPC tuning 64
2.8 MPC stability 66
2.9 Nonlinear MPC 68
References 71
3 Fuzzy control 75
3.1 Introduction 75
3.2 Fuzzy sets 75
3.3 Typical membership functions of the fuzzy sets 77
3.4 Operations with fuzzy sets 81
3.5 Fuzzy logic 83
References 91
4 Optimal control systems 92
4.1 Steady-state optimal control 92
4.2 Dynamic optimal control of batch processes 102
4.3 Dynamic optimal control of continuous processes 111
References 118
5 Multivariable control 119
5.1 Introduction 119
5.2 Multiloop control 120
5.2.1 Interaction among control loops 120
5.2.2 Pairing the control loops 126
5.2.3 Tuning the multiloop controllers 128
5.2.4 Decoupling interaction for multiloop control 129
5.3 Multivariable centralized control 133
References 134
6 Plantwide control 136
6.1 Introduction 136
6.2 Premises of plantwide control 137
6.3 Designing the plantwide control strategy 139
References 143
7 Linear discrete systems and Z transform 145
7.1 Introduction 145
7.2 Discrete systems described by input-output relationship 147
7.2.1 Sampling the continuous signals 147
7.2.2 Reconstruction of the continuous signals
from their discrete values 153
7.2.3 Analytical description of the discrete systems 156
7.2.4 Z transform 160
7.2.5 Z transform of several simple functions 162
7.2.6 Inverse of the Z transform 163
7.2.7 Z transfer function 166
7.2.8 Z transfer function of the sampled system 168
7.2.9 Z transfer function of the interconnected systems 169
7.3 Discrete PID controller 171
7.4 Other forms of the discrete controllers 173
References 175
Part II: Applied Process Engineering Control 177
8 Reaction unit control 179
8.1 Introduction 179
8.2 Basic concepts of ideal continuous and batch units 179
8.3 Temperature control 182
8.3.1 Into thermal instability 182
8.3.2 Out of thermal instability 184
8.3.3 Temperature control in practice – continuous units 188
8.3.4 Temperature control in practice – batch units 195
8.4 Pressure control 200
8.5 Liquid level control 202
8.6 pH control 202
8.6.1 pH and titration curves 202
8.6.2 pH regulator characteristics 206
8.6.3 Aspects of pH control in practice 208
8.7 End-point detection and product-quality control 210
8.7.1 Some analyzer types 210
8.7.2 End-point detection reliability issues 211
8.8 Control structure design for reaction units 212
8.8.1 Principles of control structure design 212
8.8.2 Control structure design for homogeneous ideal units 218
8.8.3 Control structure design for some heterogeneous units 222
References 230
9 Control of distillation processes 233
9.1 Economic constraints of distillation 233
9.2 The recovery factor 234
9.3 Lowering energy demand of distillation units 237
9.4 General control of continuous distillation columns 239
9.4.1 Mass and energy balance imposed control issues 239
9.4.2 Control solutions 249
9.5 Control issues of continuous distillation column dynamics 254
9.6 Control issues of batch distillation columns 259
References 260
10 Control of absorption processes 262
References 269
11 Control of extraction processes 270
References 278
12 Control of evaporation processes 279
References 286
13 Control of drying processes 287
13.1 Batch drying control 289
13.1.1 Conventional batch drying control 289
13.1.2 Advanced batch drying control 292
13.2 Continuous adiabatic drying 299
References 302
14 Control of crystallization processes 303
14.1 The process of crystallization 303
14.2 Crystal size distribution control 308
14.2.1 Model-free crystal size distribution control 309
14.2.2 Model-based crystal size distribution control 313
References 316
15 Problems and exercises 318
15.1 Advanced process control 318
15.2 Applied process engineering control 322
Index 325

Digital Textile Design (Second Edition) | Melanie Bowles and Ceri Isaac

Digital Textile Design (Second Edition)

By Melanie Bowles and Ceri Isaac

CONTENTS:

INTRODUCTION 7
CHAPTER 1
TEXTILE DESIGN AND PRINT
IN THE DIGITAL AGE 9
CHAPTER 2
DIGITAL DESIGN TUTORIALS 23
CHAPTER 3
PATTERNS AND REPEATS 87
CHAPTER 4
INTRODUCTION TO ILLUSTRATION 121
CHAPTER 5
DIGITAL CRAFT 141
CHAPTER 6
TECHNOLOGY FOR DIGITAL
TEXTILE PRINTING 167
GLOSSARY 187
RESOURCES 189
INDEX 190
CREDITS 192

INTRODUCTION
Digital technology is changing the face of textile design, from methods of creating and presenting designs to the ways in which they are realized. Working in a digital environment, designers are afforded more time to experiment, explore, and create, while manufacturing technologies offer innovative new printing solutions. This practical and inspirational book examines a new era of textile design and features clear tutorials and case studies revealing how digital techniques are being employed in the fashion, interior design, and home furnishings industries.

The development of digital printing onto fabric is changing printing methods and removing the restrictions that textile designers have traditionally faced: freed from concerns about repeat patterns and color separation that are key considerations in screen and roller printing, designers are able to work with thousands of colors and create designs with a high level of detail. There is also greater freedom for experimentation, as one-off production is now possible as well as small print runs and prints engineered specifically to fi t within a garment. Software programs such as Adobe Photoshop and Illustrator present the perfect platform for textile design. These have become the industry standard tools for textile designers, offering them the freedom to work with both bitmap and vector-based imagery, manipulate drawings and photography, and create accurate details and graphic effects.

While digital printing allows a rich mix of layered imagery, the surface and tactile qualities associated with some methods of traditional printing can be lost: as a result designers are fi nding ways to put these qualities back into the fabric using techniques such as overprinting and embellishment, and this combination of digital and handcrafted techniques has even created a new hybrid craft.

Whatever your interest in textiles—whether you are a student or professional, designer or producer—you will fi nd this to be an essential and comprehensive guide to an exciting new fi eld that is pushing the boundaries of textile design.

NEW DIRECTIONS IN TEXTILE DESIGN
As the most significant advance in fabric-printing technology since the invention of the silk screen, digital textile printing is bringing about a revolution in textile design. Designers are seeking inspiration from previously unexplored sources, and a new visual language for surface design is starting to evolve. The cross-disciplinary use of graphics software, digital photography, video, and special effects by a hybrid generation of young designers is creating a new look for printed fabrics.

Fashion designers such as Issey Miyake, Hussein Chalayan, and Comme des Garçons have continued to utilize and adapt digital design and production technologies and are breaking new ground with the creation and use of highly innovative prints that make little reference to traditional patterns: fl orals have been reinvented through the use of photography, and geometric designs as the focal point of a garment have been given a futuristic edge by designers such as Jonathan Saunders. The process is now widely used in runway fashion collections today, through the use of large engineered or placement prints where the artwork is tailored to fi t the structure of the garment. Designers working in other areas such as costume, theater, interior, and product design are also fi nding it easier to involve themselves in the creation of surface designs for their work. The accessibility of this technology through the use of service bureaus also makes it possible for artists and designers who do not have specialist knowledge of textile printing to design and produce their own fabrics and decorative surfaces.

The use of digital print has rapidly established itself within fashion and textile design, although, due to its high production costs, the major creative developments are to be found in the mid- to high end of the fashion and textile design industry (as demonstrated by the range of examples shown in this chapter). But already it is drawing together disciplines such as textiles, fashion, and interior design, changing the way that designers work. Increasingly, the integration of print is becoming as vital to the designer’s vision as the form of the garment or product itself, due to the immediacy and spontaneity of digital tools.

This chapter looks at the impact of this new technology on textile design and explores the work of both well-known and emerging designers who are using computer-aided design and digital print to their full potential throughout a wide range of applications.

DIGITAL TEXTILE PRINTING
The digital printing of textiles grew out of reprographic technologies originally developed for paper and signage printing, and it now offers the same advantages to the textile industry that digital production affords the paper- and bannerprinting businesses. For individual designers and hobbyists it is analogous to the rise of desktop publishing, albeit more costly. Technology was slower to emerge in the textile industry because of the need to develop suitable inks and large-format printers specifi cally designed to accommodate woven as well as stretchable cloth. With the emergence of large-format digital textile printers, such as the Mimaki in 1998, and then the release of industrial-scale printers in 2003 by companies such as Konica, Minolta, Reggiani, Robustelli, and Dupont, there is now the potential for major changes in the textile and fashion industries in terms of increased speed and long run capability. The introduction of the Isis printer by Osiris in 2008 means that the speed of inkjet printing machines may begin to rival that of traditional rotary screen printing.

Digital printing has perhaps four main advantages over traditional printing: speed of translation of the design onto the fabric; the ability to print intricate details and millions of colors; the possibility of producing very large-scale images; lessened impact on the environment. Traditional methods of printing based on processes similar to stenciling—including silk screen, woodblock, and gravure—fi rst require that a separate template for each color be made, and for the image to then be built up in stages as each color must be laid down separately. The more colors, the more expensive and time consuming the process, so the number of colors is limited by practical considerations, often placing considerable restraints upon the designer. Repeated patterns are the norm in industrialized traditional textile printing, and very large-scale images are also impractical as the size of the design is constrained to the exact measurements of the template.

Digital printing means that there is virtually no limit to the kinds of images that may accurately be reproduced using inkjet technology. It is this exciting advantage that has paved the way for the new styles of design that are explored in this chapter.

Textile Engineering - An Introduction Edited by Yasir Nawab

Textile Engineering - An Introduction

Edited by Yasir Nawab

Contents

1 Introduction 1
1.1 What is Textile? 1
1.2 History of Textiles 1
1.3 Status of Textiles in World Exports 3
2 Textile Raw Materials 7
2.1 Classification 7
2.2 Natural Fibers 7
2.2.1 Cotton Fibers 8
2.2.2 Flax 10
2.2.3 Jute 12
2.2.4 Other Vegetable Fibers 13
2.2.5 Wool 14
2.2.6 Silk 15
2.3 Man-made Fibers 16
2.3.1 Spinning of Man-made Fibers 16
2.4 Regenerated Fibers 17
2.4.1 Viscose Fiber 17
2.4.2 Acetate Fiber 18
2.5 Synthetic Fibers 18
2.5.1 Nylon 19
2.5.2 Polyester 20
2.5.3 Other Synthetic Fibers 20
2.5.4 Glass Fiber 21
2.5.5 Carbon Fiber 22
3 Yarn Manufacturing 25
3.1 Introduction 25
3.1.1 Yarn 25
3.1.2 Spun Yarn 25
3.1.3 Yarn Number 25
3.2 Yarn Production 27 

3.2.1 Lap 28
3.2.2 Sliver 28
3.2.3 Roving 28
3.3 Basic Preparatory Processes for Spinning Operations 28
3.3.1 Preparation of Cotton to Feed the Blow Room 28
3.3.2 Blow Room 29
3.3.3 Card 31
3.3.4 Difference Between Blow Room and Card Cleaning 33
3.3.5 Drawing 33
3.3.6 Lap Former 35
3.3.7 Comber 35
3.3.8 Roving Machine 37
3.4 Spinning Operations 39
3.4.1 Ring Spinning 39
3.4.2 Winding 40
3.4.3 Open End Rotor Spinning 41
3.4.4 Air Jet Spinning 42
3.5 Types of Yarns 44
3.5.1 Staple Spun Yarn 44
3.5.2 Monofilament Yarn 45
3.5.3 Multifilament Yarn 45
4 Fabric Manufacturing 47
4.1 Weaving 47
4.2 Warp Preparation Steps 48
4.2.1 Winding 48
4.2.2 Warping 49
4.2.3 Sizing 50
4.2.4 Drawing In 52
4.3 Weaving Mechanisms 53
4.3.1 Primary Motions 53
4.3.2 Secondary Motions 53
4.3.3 Stop Motions 53
4.4 Types of Shedding Mechanism 53
4.4.1 Tappet Shedding 54
4.4.2 Dobby Shedding 54
4.4.3 Jacquard Shedding 54
4.5 Types of Picking Mechanism 54
4.5.1 Shuttle Picking 54
4.5.2 Projectile Picking 55
4.5.3 Rapier Picking 55
4.5.4 Water Jet Picking 55
4.5.5 Air Jet Picking 55
4.6 Weave Design 56
4.6.1 Plain 56
4.6.2 Twill 56
4.6.3 Satin / Sateen 57
4.7 Specialty Weaving 57
4.8 Knitting 58
4.9 Comparison of Woven and Knitted Fabrics 59
4.10 Types of Knitting 60
4.10.1 Weft Knitting 60
4.10.2 Weft Knitting Machine Elements 61
4.11 Loop Formation Cycle with Latch Needle 63
4.12 Principle Stitches in Weft Knitting 64
4.13 Knitting Terms and Definition 65
4.13.1 Loop Parts 65
4.13.2 Technical Face and Back 65
4.13.3 Wales and Courses 66
4.13.4 Stitch Density 66
4.13.5 Stitch Length 67
4.14 Warp Knitting 67
4.14.1 Classification of Warp Knitting Machine 68
4.15 Applications of Knitted Fabrics 69
4.16 Nonwoven 69
4.16.1 Definitions 71
4.16.2 Nonwoven Products 71
4.16.3 Raw Materials for Nonwovens 72
4.17 Manufacturing of Nonwoven 73
4.17.1 Web Formation 74
4.17.2 Dry Laid Web 74
4.17.3 Wet Laid Web 76
4.17.4 Polymer Laid Web 76
4.18 Web Bonding 77
4.18.1 Thermal Bonding 78
4.18.2 Chemical Bonding 78
4.18.3 Mechanical Bonding 78
4.19 Finishing 80
4.20 Characterization of Nonwoven 80
5 Textile Processing 83
5.1 Introduction 83
5.2 Textile Pre-treatments 83
5.3 Singeing 84
5.4 Desizing 84
5.5 Scouring 85
5.6 Bleaching 86
5.7 Mercerizing 86
5.8 Heat-setting 86
5.9 Textile Dyeing 87
5.10 Dyes and Pigments 87
5.10.1 Acid Dyes 88
5.10.2 Azoic Dyes 89
5.10.3 Basic Dyes 89
5.10.4 Direct Dyes 89
5.10.5 Disperse Dyes 90
5.10.6 Reactive Dyes 90
5.10.7 Sulphur Dyes 91
5.10.8 Vat Dyes 92
5.10.9 Pigments 93
5.11 Dyeing Methods 93
5.11.1 Exhaust Dyeing 93
5.11.2 Pad Dyeing 94
5.12 Dyeing Machinery 94
5.12.1 Exhaust Dyeing Machines 94
5.12.2 Pad Dyeing Machines 94
5.13 Blends Dyeing 95
5.14 Textile Printing 95
5.15 Common Styles of Textile Printing 95
5.15.1 Direct Printing 95
5.15.2 Transfer Printing 95
5.15.3 Discharge Printing 95
5.15.4 Resist Printing 96
5.16 Common Methods of Textile Printing 96
5.16.1 Block Printing 96
5.16.2 Screen Printing 96
5.16.3 Roller Printing 96
5.16.4 Digital Printing 96
5.17 Main Steps in Direct Printing 97
5.17.1 Fabric Preparation 97
5.17.2 Print-paste Preparation 97
5.17.3 Printing 97
5.17.4 Drying 98
5.17.5 Fixation 98
5.17.6 Washing-off 98
5.18 Textile Finishing 98
5.19 Chemical Finishing 100
5.19.1 Softening 100
5.19.2 Stiffening / Hand-building 101
5.19.3 Easy-care, Wrinkle Recovery and Durable Press Finishing 101
5.19.4 Water Repellent Finishing 102
5.19.5 Stain Resistance Finishing 103
5.19.6 Stain or Soil Release Finishing 103
5.19.7 Flame Retardant Finishing 104
5.19.8 Anti-microbial Finishing 105
5.19.9 Bio-polishing 105
5.19.10 Moisture Management Finishing 106
5.19.11 Anti-static Finishing 106
5.19.12 Optical Brightening 106
5.20 Mechanical Finishing 106
5.20.1 Napping 106
5.20.2 Shearing 107
5.20.3 Sueding / Emerising 107
5.20.4 Calendering 107
5.20.5 Compacting 108
5.20.6 Relaxation Drying 108
5.20.7 Decatising 108
6 Clothing 111
6.1 Introduction 111
6.2 What is Garment / Apparel / Clothing? 111
6.3 Types of Garments 111
6.4 Global Apparel Industry 113
6.5 Structure of an Apparel Firm 114
6.6 Marketing Division 115
6.7 Finance / Admin Division 116
6.8 Manufacturing Division 116
6.9 Operations Division 117
6.10 Clothing Production 119
6.11 Sampling 119
6.12 Order Planning 121
6.13 Lay Planning 123
6.14 Spreading 125
6.15 Cutting 127
6.16 Numbering and Bundling 128
6.17 Stitching 129
6.17.1 Interlacing 130
6.17.2 Intralooping 130
6.17.3 Interlooping 130
6.18 Finishing 131
6.19 Packing 131
7 Technical Textiles 133
7.1 Introduction 133
7.2 Functions of Technical Textile 133
7.3 Categories of Technical Textiles 133

7.3.1 Agrotech 134
7.3.2 Buildtech 135
7.3.3 Clothtech 135
7.3.4 Geotech 136
7.3.5 Hometech 137
7.3.6 Indutech 137
7.3.7 Medtech 137
7.3.8 Mobiltech 138
7.3.9 Oekotech 139
7.3.10 Packtech 139
7.3.11 Protech 140
7.3.12 Sporttech 140
8 Textile Testing 143
8.1 Introduction 143
8.2 Quality Control 143
8.3 Standardization of Testing 143
8.4 Repeatability and Reproducibility 144
8.5 Sampling 144
8.5.1 Consignment 144
8.5.2 Test Lot 144
8.5.3 Laboratory Sample 144
8.5.4 Test Specimen 145
8.5.5 Package 145
8.6 Moisture Content & Moisture Regain 145
8.7 Standard Atmospheric Conditions for Testing 145
8.8 Testing of Fibers 145
8.9 Testing of Yarn 148
8.9.1 Linear Density 148
8.9.2 Direct System 148
8.9.3 Indirect System 148
8.9.4 Evenness of Yarn 149
8.9.5 Visual Examination 149
8.9.6 Cut and Weigh Method 150
8.9.7 USTER Evenness Tester 151
8.9.8 Yarn Hairiness 151
8.9.9 Tensile Strength 151
8.10 Types of Tensile Strength Testing Machines 152
8.11 Fabric Tests 152
8.11.1 Strip Test 152
8.11.2 Grab Test 153
8.11.3 Tear Tests 153
8.11.4 Elmendorf Tear Tester 153
8.11.5 Bursting Strength of Fabric 154
8.11.6 Weight per Square Yard (GSM) 155
8.11.7 Color Fastness to Perspiration 155
8.11.8 Abrasion Resistance of Fabrics (Accelerator Method) 155
8.11.9 Water Repellency (Spray Test) 156
8.11.10 Water Resistance / Impact Penetration Test 156
8.11.11 Air Permeability 157
8.11.12 Moisture Management Test 157
8.11.13 Colour Fastness 157
8.11.14 Thermal Transmittance of Textile Materials 157
8.11.15 Effect of Repeated Home Laundering on Textiles 158
8.11.16 Colour Fastness to Perspiration 158
8.11.17 Seam Strength 158
9 Disposal and Recycling of Textiles 161
9.1 Introduction 161 

9.2 Environmental Impacts of Textiles 164
9.2.1 Impact of Laundering 164
9.2.2 Impact of Dry Cleaning 165
9.2.3 Maintenance Chemicals 165
9.2.4 Emissions 165
9.3 Ecologically Beneficial Practices 167
9.4 Textile Recycling 168
9.4.1 Conversion to New Products 169
9.4.2 Wiping and Polishing Cloths 170
9.4.3 Landfill and Incineration for Energy 170
9.5 Methods of Recycling 170
9.5.1 Easy Recyclable Textile Products 171
9.5.2 Single Polymer Design 173
9.6 Easily Separable Components 173
9.7 Solid Waste Management 174
10 Quality Control and Quality Assurance 177
10.1 Introduction 177

10.2 Transcendental View of Quality 177
10.3 Product-based View 177
10.4 User-based View 178
10.5 Manufacturing-based View 178
10.6 Value-based View 178
10.7 Quality Control 180
10.7.1 On-line Quality Control System 182
10.7.2 Off-line Quality Control System 182
10.8 Quality Assurance 183
10.9 Quality Assurance Policies and Records 185
10.10 Need of Quality Assurance in Textile Industry 187
10.10.1 Main Objective 187
10.10.2 Major Responsibilities 187
10.10.3 Stimulate Research Effort 187
10.10.4 Identify and Address the Various Problems 188
10.11 Difference between Quality Assurance and Quality Control 188
11 Computer Applications in Textiles 191
11.1 Introduction 191
11.2 Industrial Applications 192
11.3 Enterprise Resource Planning (ERP) 192
11.3.1 CAD 192
11.3.2 CAM 194
11.3.3 Other Areas ERP Helping 195
11.3.4 Machine Monitoring 196
11.3.5 Report Generation 196
11.3.6 Production Plan 196
11.3.7 Inventory Management 197
11.3.8 Maintenance 197
11.3.9 Machine Setting 197
11.3.10 Quality Management 197
11.4 Image Analysis 198
11.5 Data Mining 198
Index 201

Sustainable Innovations in Apparel Production | Edited by Subramanian Senthilkannan Muthu

Sustainable Innovations in Apparel Production

Edited by Subramanian Senthilkannan Muthu

Contents

Laser-Based Apparel Production . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
P. Senthil Kumar and S. Suganya
Sustainable Wastewater Treatment Methods for
Textile Industry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Aravin Prince Periyasamy, Sunil Kumar Ramamoorthy, Samson Rwawiire
and Yan Zhao
New Tools and Techniques for Measuring
Sustainability in Clothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
P. Senthil Kumar and P. R. Yaashikaa

Laser-Based Apparel Production
P. Senthil Kumar and S. Suganya

Abstract 

LASER (Light Amplification by Stimulated Emission of Radiation) technology is being largely used in apparel industry for cutting, patterning garments, designer neckties, and denim fading with 3D body scanning and engraving leather since nineteenth century. Laser cut design tends to be reserved for haute couture designs and reduced low cost, flexibility, and anti-counterfeiting to produce apparel in ready-to-wear collections. Laser light is a form of electromagnetic radiation used to cleave various materials with high accuracy in cutting, sealing fabric edges in order to prevent fraying. The change in energy states within the atoms of certain materials leads to produce light by laser. And that has few basic characteristics, namely intensity, coherency, monochromaticity, and collimation.

These are helpful to distinguish laser light from natural light. Generally, laser beams are narrow, travel in parallel lines, but do not spread out or diverge as light from most normal sources. Therefore, using laser cuts without any pressure on the fabric is meant for no extra energy requirement other than laser. It tends to no unintended marks left on the fabric especially in silk and lace. Adopting high-energy laser cuts material by melting, burning, or vaporizing it. Most significantly, laser beam decomposes dye, resulting in producing vapors followed by venting them away from garment. This is how denim fading works. While scanning the universal barcodes to identify products such as apparels, fashion accessories, the following lasers are used such as CO2 laser, neodymium (Nd) laser, and neodymium yttrium-aluminum-garnet (Nd-YAG) lasers. They use precise concentrated beam of light. CO2 laser is a gas laser, producing an infrared light to absorb by organic material. Solid-state lasers such as Nd and Nd-YAG lasers, on the other hand, rely on a crystal to create light beam. Yet, it is hard to reproduce in an exact way. Hence, laser cut makes each ideal task to create an identical design; many countries are unaware of this technology. But the laser cut clothes are shell out for a lot of cash.

However, safety issues and gases used in laser apparels must be replenished to meet multi-fiber agreement regime to make textile products more safe, clean, and competitive. This chapter focuses on laser technology in the apparel production and their potential hazards in health-related concerns.

Keywords Laser cut design _ Engraving _ Scanning _ 3D _ Hazards Light beam

1 Introduction
For many decades, LASER technology is being used in apparel industry. Recently, laser technological developments are gripping textile field to improve the product and supply chain more efficient. Laser plays major role in cutting, patterning, welding and designing, scanning, fading, and engraving [1]. Laser light is an energy source, a form of electromagnetic radiation which produces light by changing energy states within the atoms of certain materials. Light emitted from laser falls on following characteristics, namely intensity, coherency, monochromaticity, and collimation. Though laser beams are not divergent, their intensity and power can be precisely controlled. Furthermore, laser can focus to a desired object at specific angle according to its application [2]. Similarly, laser passes on denim to decompose dye and vaporize that further results in fading. In particular, helium–neon lasers are used to scan the universal barcodes to identify products such as apparels, fashion accessories in retail stores. It also strengthens the security policy for goods sold in market, preventing from duplicating. To overcome such economical issue, digital storage of goods is encouraged rather than physical patterns storage. Digital artwork storage can be later converted into physical samples using lasers.

Denim-engraving techniques have been developing for value addition purpose using laser which can be a substitute for traditional methods (Denim-distressing), whereby laser-based methods offer high degree of sophistication to the denim segment compared to non-laser methods. Laser is feasible at the extent of cutting flexible objects, i.e., fabric to rigid metal. To achieve this, industrialists are looking forward to laser equipment for its advantages in accuracy, efficiency, simplicity, and the scope of automation. Traditional cutting tools for cutting garments mostly damage the quality of objects especially on exquisite materials as the cutting force [3] is applied to band blades, disks, and reciprocating knives. In other words, it leads to inaccurate cutting.

Traditional methods also require man power such as operator to pay full attention during cutting to trade-off a trade-off between two incompatible features, i.e., cutting speed and its accuracy. Indeed, limitations in traditional methods include intricacy of the cut components, tool longevity, and machine downtime during tool servicing. While employing laser-based tools and devices, aforesaid limitations can be eliminated with improved efficiency and reduced cost. Use of laser in apparel production contributes high speed in cutting and processing, high precision, and simple operation. It forms pavement to cut leather graphics to draw any desirable clothing model. During this, laser beam is collimated to focus on a fine dot for precise cutting. This also utilizes least size of the garment with high efficiency and exquisite tailoring than the non-laser-cutting methods by spectrum. Laser technology aims to reduce cost in processing, flexibility in product development, and anti-counterfeiting. In addition, garment industry eliminates tedious handling systems operated by workers in non-laser workstations in order to implement safety guidelines [4].

The Fabric of Interface: Mobile Media, Design and Gender PDF by Stephen Monteiro

The Fabric of Interface: Mobile Media, Design, and Gender

By Stephen Monteiro

Contents

Acknowledgments ix
Introduction 1
1 Woven Memory 23
2 Image Fabric 59
3 Piecework 85
4 Domestic Disturbances 115
Notes 145
Index 181

Introduction
Contemporary digital media appear to have little in common with those of only a generation ago. In addition to transformations in their content, infrastructure, and application, our interactions and physical engagement with the digital media object have changed fundamentally. Encounters with digital networks and media frequently occur through handheld, electronic devices that accompany us through the day, carried in our back pocket or handbag. We turn and tilt these small plastic or metal frames with our hands and arms. We stroke and tap their glass screens with our fingertips.

Through these physical interactions with the object and its surface, we make things: images, links, sites, networks. Our ability to effectively and efficiently identify patterns and build connections in this bodily performance, to bind the material of networked digital culture in new ways— whether it be in a game or on a social media platform—may earn us money, points, credit, followers, or some other desired quantitative reward.

Digital media’s most unassuming components and operations are not self-evident or neutral entities, but cultural artifacts forged from longstanding social and ideological forces. As manual dexterity, patternmaking, and linking have risen to the forefront of everyday digital practice, our media interactions have taken on traits common to textile and needlecraft culture. Our smartphones and tablets share much with the handloom, the needlepoint hoop, and the lap-sized quilting frame. Each of these represents a portable platform, upon which one can create patterns, images, and other potentially meaningful visual configurations. Historically, looms, hoops, and quilting frames have been tools of the home, but they also have served as a means for greater social interaction, as with the communal functions of pattern sharing, fabric exchange, and quilting bees. Likewise, with the advent of the networked platforms for personal data and information sharing known collectively as social media, our portable electronics have become tools for a variety of interactions with others through the digital material that we access and its relation to our everyday circulation through the social sphere.

How may a handheld screen function like a loom, visual data function like swatches of fabric, and tactile interfaces function like needlework? What can such affinities tell us about communicative technology’s adaptation of popular cultural codes? How does this create new ways of thinking about digital media’s relationship to labor, identity, space, and the senses? Such questions frame the perspective and scope of The Fabric of Interface. Through its sustained exploration of weaving, fabric manipulation, and needlecraft as fundamental to historical and contemporary digital frameworks and interfaces, this book identifies important connections between contemporary networked media and practices often construed as alien to media technologies. It contends that social distinctions and gender divisions are reflected not only in what is made and circulated on digital devices and networks—as has been argued elsewhere1—but also through the immaterial and material forms, structures, and requirements of these devices and networks as they play out in electronic and physical actions and exchanges.

In their study of digital interaction design, Jay Bolter and Diane Gromala assert: “If we only look through the interface, we cannot appreciate the ways it shapes our experience. … If we cannot also step back and see the interface as a technical creation, then we are missing half of the experience that new digital media can offer.”2 Stepping back to examine the correlation of digital and textile performativity in haptic and visual interface is significant for two reasons, both of which have consequences far beyond digital interactivity. First, it brings to the surface elements of computing’s historical dependency on textile design, its production methods, and its labor models.

This story is buried in computing’s material past and scattered across its global sites of hard- and software manufacture and assembly, where women regularly have been responsible for the manual labor of weaving memory, threading hardwired programs, and integrating circuits. Second, the reification of this relationship in contemporary interface design and user practices raises vital questions about the relationship between gender and bodily interface in mobile media at a moment when such technologies would seem to transcend the issue. When considering ways an iPhone might be gendered, for example, one may be prone to begin and end with obvious marketing maneuvers such as the introduction of a pink (or “rose gold,” according to Apple) back cover. “Are you man enough for a pink iPhone 6s?” Esquire asked its readers when the cover was introduced, referring to the result as a “powder-puff smartphone.”3 Yet such overt gestures toward the most conventional methods of coding gender in the everyday imply that these devices and their functionality are otherwise gender-neutral platforms upon which such codes may be added. In fact, the availability of colored covers or the production and use of deliberately gender-specific apps or language represent diversions that effectively obscure far more pervasive, but less easily identifiable, gendered characteristics of mobile media.

The look, feel, and function of contemporary media devices and their supporting software derive from deep-seated patterns of cultural practice, social structuring, and technological hierarchizing. This reflects Lisa Gitelman’s contention that media are “muddy” entities requiring consideration of how they are formed through social protocol as much as how they function technologically. “Media include a vast clutter of normative rules and default conditions, which gather and adhere like a nebulous array around a technological nucleus,” she states.4 The approach of this book differs from Gitelman’s, however, in its emphasis of the technological nucleus itself as constructed from normative rules and default conditions. In other words, socially constructed rules and conditions not only form around a technology, but also contribute significantly to that technology’s formation in the first place. Any medium, any technology, is already muddy when it comes out of the box.

This book explores the muddy roots of networked digital media’s forms and practices in emphasizing their historical, cultural, and aesthetic dependency on gendered embodiment and labor forms. Making the link between sewing, weaving, and quilting and contemporary technologies gives access to new ways of conceptualizing hardware and software design, sensorial experience, and personal networked media practice. It contributes to an alternative historical narrative of digital interactivity—one centered on the relationship between gender and interface aesthetics. Recent changes in the screen as an interactive object and tool represent a critical turning point in this story, producing new physical and ideological relationships between user, device, and digital production. Any consideration of the material design and functioning of media—in this case, the hardware of portable touchscreens and wearables and the software that guides and brings meaning to our actions upon them—must be informed by these long-established gendered discourses of social differentiation and power imbalance that they reify and sustain.

Producing such an alternative narrative sharpens our understanding of the ways contemporary digital media may represent new modes of social production and interaction, and in what ways they merely adapt and redeploy modes already embedded in the history of computing and digital communication. Specifically, this narrative challenges the perceived breaks between industrial (or commercial) computing and personal computing in the closing decades of the twentieth century, and personal computing and social media in the opening decades of this century. Bridging these shifts is digital culture’s continued reliance on textile and needlecraft practices, techniques, and methods drawn from spheres alternately labeled as feminine, private, and domestic. In this way, qualities of intimacy and engagement seen as novel to today’s touchscreen media devices are in fact attributes already present in earlier conditions of digital production, where manual gestures common to home handicrafts played a fundamental role in the manufacture of mainframes.

Melt Blowing: Equipment, Technology, and Polymer Fibrous Materials PDF by A.V. Makarevich, L.S. Pinchuk, and V.A. Goldade

Melt Blowing: Equipment, Technology, and Polymer Fibrous Materials

by A.V. Makarevich, L.S. Pinchuk, and V.A. Goldade

Preface
One of the recently emerging techniques of fibrous materials production, melt blowing, consists of forming fibers from substances heated above their melting (crystalline) or glass transition (glass-like) point with further blowing by gas flow. The sprayed fibrous mass is then cooled to solidification either in a gas flow or upon deposition on the forming substrate.

Realized from polymers and then ceramics, the melt blowing technique has enriched materials science, engineering, and all commodity products by novel types of fibrous materials and products made from them with a unique combination of properties. The reasons for the popularity of melt blowing are the following.

The shape stability and strength of melt-blown materials and products are controllable technological parameters that depend on the diameter and the intensity of the adhesive interaction between fibers and the number of contacts between them.

The greater area of fiber surface in contrast to negligible clearances in between is the source of the uniqueness of melt-blown materials as systems whose properties are governed to a great degree by surface phenomena. Dielectric materials manufactured by melt blowing are subjected to the rigorous effects of heat, deformation, and friction during processing which is accompanied by natural electrical polarization of fibers. The fibers are transferred into an electret state (an electret is a dielectric that preserves its electrical polarization for a long time), which makes melt-blown materials the source of a permanent electrical field.

The melt blowing technique creates new vistas for controlling the structure and properties of fibrous materials. At least four areas of control can be outlined.

First is the chemical composition of the material extruded into fibers. The second area is fiber transportation within the gas flow where the material is in a structurally sensitive state, either viscous-flow or viscoelastic. At this stage, it is convenient to modify fibers by chemical, physical, and biological methods. Third, the fiber diameter (from portions a micrometer to a millimeter) and a uniformity of the adhesion of dispersed components to the fibers can be adjusted to impart new functional properties to the material as a whole. The fourth area is the texture of melt-blown materials and products that is determined by the mutual disposition and bonding of fibers to one another. Development of a great variety of melt-blown materials has perceptibly impacted engineering domains and life as a whole. Following are some examples that confirm this fact.

Melt-blown materials can serve an ideal basis for biosorbents and biocatalysts in a number of biotechnological processes whose success influences their commercial prospects (biotechnology is a combination of industrial procedures using living organisms and biological processes in manufacture). Microorganisms immobilized on a fiber surface are easily accessible to reagents in liquid and gaseous phases. However, the shape stability of the fibrous carcass presents a mechanical barrier that separates microbial colonies from the environment. Weak and superweak physical fields generated by melt-blown materials also stimulate the vitality of microorganisms.

Melt-blown materials have opened new ways of solving problems in engineering ecology. Its methodology and tools require constant change in the range of filtering materials. Melt blowing technology has made it possible to simplify the problem of cleaning industrial wastewater and gas ejections, and to develop systems for entrapping petroleum products, organic solvents, heavy metal ions and to inactivate them biologically. Recently elaborated melt-blown materials based on readily fusing glue compositions, also soft but preserving their shape lining, decorating, and other accessory materials have enriched light industry with novel techniques and products.

l'v1elt-blown materials based on water-soluble polymers and their gels have formed the basis of a vast variety of medical, hygiene, cosmetic, and perfume products of a new generation without which modern civilization is unthinkable. Unfortunately, despite almost a 50-year history, the melt blowing technique, for a number of reasons to be expounded further, is little known thus far. Until now, there has not been in any monograph in the literature that generalizes its objectives, means of attainment, and recent successes. vVhat is more, the methodology, including its original tools, design of technological equipment, and instrumentation for implementing this unusual technology has not yet been elucidated. This book is the first publication where the physicochemical basis of the melt blowing technique is systematized, and fundamental flow charts, designs of the main joints, characteristics and fields of application for melt-blown materials are correlated. The authors have endeavored to describe precursors' works at length, even though the essentials of the book constitute investigations of their own completed at the MetalPolymer Research Institute (MPRI) of the National Academy of Sciences of Belarus (Gomel, Belarus) with a Design Bureau and pilot plant. The authors express their gratitude to MPRI's Director, Correspondent Member of NASB, Prof. Yu. M. Pleskachevsky for attention to this work; Head of "Metal-Polymer" Co., Ph.D. A.I. Chernorubashkin, and Chief Designer of the company, A.Y. Sikanevich, for permission to present data of the commercial use of melt-blown materials: Ex-Vice President of Korea Institute of Science and Technology (KIST), Prof. O.K. Kwon, Head of Tribology Center, Dr. U.S. Choi and Principal Researcher, Dr. B.G. Alm of this Institute for cooperation in modernizing the melt blowing equipment, investigations, and the adoption of magnetic filtering materials in industry. We are also grateful to researchers, Ph.D. A.G. Kravtsov, I.Yu. Ukhartseva, and Yu.Y. Gromyko for creative contributions to the experimental investigations of magnetic melt-blown materials. The authors are thankful to postgraduate S.Y. Zotov and fellow-worker 1.S. Pushkina for their invaluable service in preparing this treatise.

Contents

1. Introduction (Historical Review) ......................... 1
2. Melt Blowing Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.1 Main Technological Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Modern Trends in Melt mowing Techniques. . . . . . . . . . . . . . .. 10
3. Equipment................................................ 21
3.1 Spray Heads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 21
3.1.1 Basic Designs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 21
3.1.2 ~10dified Heads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 28
3.2 Auxiliary Equipment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 42
4. Structure of Melt-Blown Polymer
Fibrous Materials (PFM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 53
4.1 Major Structural Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . .. 53
4.2 Effect of Different Technological Regimes
011 PFM Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 60
5. Specific Properties of Melt-Blown PFM .................. 65
5.1 Physicochemical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . .. 65
5.2 Electret Charge in Melt-Blown l\1aterials . . . . . . . . . . . . . . . . .. 75
6. Fibrous Materials in Filtration Systems. . . . . . . . . . . . . . . . . .. 83
6.1 Efficiency of Filtration Systems .......................... 83
6.2 Filtration Mechanisms .................................. 85
6.2.1 Mechanisms of Particle Precipitation. . . . . . . . . . . . . . .. 85
6.2.2 Surface and Depth Filtration ...................... 86
6.2.3 Electrostatic Precipitation. . . . . . . . . . . . . . . . . . . . . . . .. 89
6.2.4 Precipitation and Coagulation in a Magnetic Field. . .. 91
7. Electret Filtering PFM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 95
7.1 Mechanism of PFM Polarization. . . . . . . . . . . . . . . . . . . . . . . . .. 95
7.2 Capillary Phenomena. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 99
7.3 Production Process and Properties of Electret PFM ........ 103
7.4 Applications ........................................... 106
8. Magnetic Filtering PFM .................................. 111
8.1 Background............................................ 111
8.2 Simulation of Magnetic Deposition in PFM ................ 113
8.3 Theory versus Experiment ............................... 117
8.4 Magnetization of PFM .................................. 117
8.5 Magnetic Coagulation of Particles in PFM ................. 121
8.6 Magnetic Capillary Phenomena .......................... 127
8.7 Serviceability of Magnetic PFM-Based Filters .............. 132
9. Adsorptive and Microbicidal PFM ........................ 135
9.1 PFM Modified by Porous Adsorbents ..................... 135
9.2 PFM as Adsorbents of Oil Product8 ...................... 137
9.3 Complex-Forming PFM ................................. 138
9.4 Adsorptive-Microbicidal PFM ............................ 143
10. PFM as Carriers of Microorganisms ...................... 147
10.1 Biofilters with Polymer Fibrous Biomass Carriers ........... 147
10.2 Effect of Magnetic Fields on the Growth Proce8ses
of Microorganisms ...................................... 155
11. Other Applications of PFM ............................... 161
11.1 Household Uses ........................................ 161
11.2 Industry ............................................... 165
11.3 Construction ........................................... 168
11.4 Medicine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
11.5 Packing ............................................... 173
11.6 Protection of Products and Environment .................. 175
12. Ecological and Social Problems ........................... 179
12.1 Solution of Ecological Problem8 .......................... 179
12.1.1 Purification of Indu8trial Ga8e8 .................... 180
12.1.2 Wa8tewatcr Purification .......................... 181
12.1.3 Melioration ...................................... 182
12.1.4 Oil and Chemical Sorbents ........................ 182
12.2 Regeneration, Utilization, and Burial ..................... 184
12.3 Economic Estimates .................................... 188
13. Conclusion ............................................... 191
References .................................................... 193
Subject Index ................................................ 206