Page 201 - Materials Chemistry, Second Edition

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Sustainable Industrial Design and Waste Management
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semiskilled and marginally employable workers at the primary processing
level including used clothing dealers, rag graders, and fiber recyclers.
Textile waste can be classified into two categories: pre-consumer and
post-consumer (Dadd, 2004). The pre-consumer textile waste category con-
sists of byproduct materials from the textile, fiber, and cotton industries.
Pre-consumer textile waste can be recycled into new raw materials for the
automotive, furniture, mattress, coarse yarn, female accessories, home fur-
nishings, paper, and other industries. The post-consumer textile waste cate-
gory consists of any type of garments or household article, made of some
manufactured textile, that the owner no longer needs and decides to discard.
These items are discarded either because they are worn out, damaged, or are
no longer fashionable. Many items are made from fabric items recut to make
new items, such as t-shirts cut to make cleaning cloths.

5.10 Recycling of Composite Packaging Materials
Food packaging has been essential since the birth of the industrial era when
consumers moved into cities, away from the food production areas. But food
preservation and storage has existed since ancient times. Natural materials
like woven bamboo baskets, animal skins, and clay have been used to store,
distribute, and protect food since the beginning of civilization.
Before the 19th century, food packaging was used mostly for transport-
ing goods from the place of production to the consumer. But as people
moved into ever-expanding towns and cities, during the early industrial age,
the role of packaging widened from that of only containing products to one
of protecting them too. So, with the beginning of industrialization, the search
began for better ways of preserving foodstuffs and packaging became the
main “component” for the development of long-life preserved foods. Today,
“packaging is not of itself a product in the usual sense, it is a delivering tool
to get a product to a consumer, safely, in excellent condition and fit-for-use;
it is a fundamental part of any packaged goods” (Olah, 2004).
Glass making existed 6,000 years ago, but it was not until 200 BC that
a Syrian discovered that he could blow molten glass with a pipe, and turn it
to make a bottle (Planet Ark, 2005). So, before using the paper carton, the
glass bottle was used for milk packaging. But glass bottles had some disad-
vantages as they are breakable and need to be handled with care; in addition,
glass bottles are heavy and they need much energy for their transportation.
Although they were reusable or refillable, they first had to be cleaned to
a sterile state before reuse, and the cleaning process required large amounts
of energy. Moreover, milk has always been difficult to preserve, due to its
susceptibility to disease-causing agents which was one of the reasons for
high infant mortality rates. Milk was also easily spoiled and quickly
absorbed odors (Planet Ark, 2005). These conditions required localized dairy
operations and intensive energy for distributing the milk packaged in glass