Wang Recycling in Textiles

1. Auflage 2006
ISBN: 978-1-84569-142-4
Verlag: Elsevier Science & Techn.
Format: EPUB
Kopierschutz: 6 - ePub Watermark

E-Book, Englisch, 248 Seiten

Reihe: Woodhead Publishing Series in Textiles

An increasing amount of waste is generated each year from textiles and their production. For economic and environmental reasons it is necessary that as much of this waste as possible is recycled instead of being disposed of in landfill sites. In reality the rate of textile recycling is still relatively low. On average, approximately ten million tonnes of textile waste is currently dumped in Europe and America each year. Considering the diversity of fibrous waste and structures, many technologies must work in concert in an integrated industry in order to increase the rate of recycling. Recycling in textiles shows how this can be achieved.The first part of the book introduces the subject by looking at the general issues involved and the technologies concerned. Part Two explores the chemical aspects of textile recycling. Part Three focuses on recycled textile products, including nonwovens and alternative fibres. Finally, the last part of the book discusses possible applications of recycled textiles, including using recycled products in the operating theatre, for soil stabilisation and in concrete reinforcement.Recycling in textiles presents several promising technologies and ideas for recycling systems. This is the first book of its kind to bring together textile recycling issues, technology, products, processes and applications. It will prove an invaluable guide to all those in the industry who are now looking for ways to recycle their textile waste. - Provides extensive coverage of this hot topic - An invaluable guide for all in the textile industry - Learn how to increase the rate of recycling

Autoren/Hrsg.

Wang, Youjiang

Leseproben

3 Designing textile products that are easy to recycle
B. Gulich    Saxon Textile Research Institute, Germany 3.1 History
For centuries, textiles have been developed and made to serve particular purposes. Originally, they were used to protect users from cold, heat, light, and to preserve modesty but, step by step, they have become media to express personality, wealth, or interest in fashion. Within the last century, the means available in this context have reached a distinctly higher level when compared to the centuries and millennia before, due to novel fibre materials and new processes to make threads and fabrics. For ages, technical applications were limited to instruments for hunting animals or equipping human dwellings. Nowadays, our industrialised society uses textiles for a wide range of purposes other than for making garments. For centuries, fibres have been reclaimed from end-of-life textiles and made into textile products, which has become a well-proven and effective way of recycling. The natural availability of reproducing fibres is limited and people have always tried to control consumption. The relatively modest living standard before industrialisation added to this approach. In the beginning, end-of-life fibres were badly torn; the only field to re-use them was paper-making. As early as in 105 AD, the Chinese were able to make rags into paper. In the 15th and 16th centuries, simple mechanical ways to recycle long and singled fibres started the textile material cycle. In times of textile raw material scarcity, the recycling of end-of-life textiles became a necessity, and craftsmen or even the recycling industry tried to achieve higher output this way. Textile waste was looked upon as a valuable source of raw material. However, with only a relatively small number of fibre materials and only a limited range of applications of textiles known, it was of little interest to design textiles in such a way that they would be easy to recycle. The main focus is the same as today: on their particular purpose. However, even if our contemporary society tends to dispose of end-of-life materials, and even if synthetic fibres seem to provide an abundance of textile raw materials, textile recycling remains a current necessity. The ways of recycling textile materials must develop, along with the technical progress in the textile industry and the continuously rising call for textile products in all fields of application. Resources to make primary synthetic fibres are becoming less and less and the world population is rising, so it is clear that textile recycling needs to stay on the agenda. This is what makes it necessary to develop processes to design textiles that are easy to recycle. 3.2 Product responsibility
The law in Germany on Material Cycles and Waste Materials (1996) and on End-of-Life Vehicles (2002) attaches particular importance to material cycles and to producers being responsible for their products in the sense of eco-friendly manufacture. On a global scale, it can be seen that various governments put more or less emphasis on such legal regulations. The highest-developed countries should be pioneers in this respect. So what does product responsibility mean, and how can textiles be produced in accordance with it? Producers should • develop, make and sell textile products which, at the end of life, can be recycled or disposed of in an eco-friendly way, • have integrated product policies, • attempt to use reclaimed textile waste or secondary raw materials as much as possible to make new textiles or textile-based products, • at the end of product life, take back their products. 3.3 Current situation in Germany
3.3.1 Clothes
Designers are expected to feel responsible for production waste and for end-of-life products. This is what they have been faced with for a long time. Both in the clothes-making industry and in enterprises such as processing and finishing of textiles, production waste is generally clearly defined and much is suitable to be reused. In other German medium-size enterprises, there are high-performance systems to capture, sort and re-use end-of-life textiles from households. One conventional way to re-use them is the manufacture of reclaimed fibres to make nonwovens or yarns. State-of-the-art machines1 have made it possible to process end-of-use clothing to achieve reclaimed fibres. Buttons and other non-textile components are no longer manually detached as that would not be economical. Equipment now available allows total separation of non-textile components. This means, the basic requirements are met with regard to reclaimed fibres being economically processed and re-used. 3.3.2 Technical textiles
For end-of-life industrial textiles, including mainly technical textiles, recycling systems are generally not yet sufficient. One of the reasons is that there are few fields in which to re-use them. However, if they were designed to be easily recycled, such fields could well be found. Technical textiles are characterised by: • a continuously rising call for them • new fields of application and functionality, novel products, new customers • composite materials: combinations with non-textile products to enhance functionality (interior linings of vehicles, insulating materials) • contamination caused during life by non-textile components, e.g. with filters, felts used in paper-making, packing materials. Technical textiles, according to their particular uses, are more or less suitable to be designed in a way that makes them easy to recycle. The following would be helpful: • Early collaboration of the manufacturers with other industrial enterprises involved in the product in question, above all with those who use or market it. • Development of strategies to re-use or dispose of a product, making these strategies part of marketing. • Design, keeping in mind how a product, meant to be sold tomorrow, can be recycled or disposed of the day after tomorrow. 3.4 Basic methods
A great challenge in the design of products that are easy to recycle is seen in the development of eco-friendly products. Waste should be avoided both in the production process and when disposing of products. In addition, material substance should, at the end of product life, be suitable to be returned into the material cycle (recycling). This is also true of making textiles and, in particular, of technical textiles. Generally, it is the designer who decides on the structure of a product and on the best materials to use. He/she will, of course, take functionality and budget into consideration. Functionality is achieved by choosing or combining the right materials. Those suitable for making technical textiles may be both textile fibres and non-textile materials such as foams, films and plastic materials. Textile materials may, depending on the manufacturing process used, partially or even totally lose their textile character. The materials chosen have an influence on the processes of manufacturing as well as on the processes of recycling and disposing the product at the end of its life. Indeed, they predetermine all these processes. Materials may be used in a variety of systems. Figure 3.1 gives an overview of the systems of materials generally available and their potentials to make products that are fully functional and designed to be easily recycled. 3.1 Principles of material systems: recycling-friendly construction and functionality. Products consisting of only one material in a single system (non-composite) are easy and pure to re-use. With them, it is not generally necessary to separate the product structure prior to processing. This is why single-material systems are preferable when it comes to the design of products easy to recycle. Such systems, however, might meet their limits in cases where • high quantities of special materials are used, • the material used is expensive, • product functionality requires the use of several layers of material (single-material composites). Combinations of different kinds of textile made from the same polymer (e.g. PP fibre material and PP film or coating) are single-material composite systems, which are also easy to recycle. If the required characteristics of a product are not achievable using but one material, multi-material composite systems are necessary. Systems containing separable composites need to be disassembled prior to recycling, which can be done manually or by machine. This is what happens, for example, to non-textile functional elements used within garments, and to technical textiles. Processes such as glueing, laminating or stitching result in composites which cannot be separated. With regard to complete re-use, the materials chosen should go well together so they can be processed together. Currently, processing makes sense as long as the secondary raw material produced can be well marketed. Reclaimed fibres mixed together are one example of how multi-material composite...