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CHAPTER 5

Toxic Waste From Leather

Industries

N.M. Sivaram*, Debabrata Barik †
* Department of Mechanical Engineering, National Institute of Technology Puducherry, Karaikal, U.T. of
Puducherry, India
† Department of Mechanical Engineering, Karpagam Academy of Higher Education, Coimbatore, India

5.1 LEATHER INDUSTRY
Leather industry is a very old manufacturing sector producing a broad range
of goods such as leather footwear, leather bags, leather garments, and so on.
The raw material used in leather industry is derived from the waste prod-
uct of food industry, specifically from meat processing. This waste product
is converted into desirable and useful leather products [1]. Leather and its
products are one of the most traded products globally. They are produced
from renewable and readily available resource. The leather industry trade is
presently exceeding US$ 80 billion in a year and this is expected to grow as
there is increase in population and urbanization of the countries [2].
The consumption of leather products by the humans is very common
and used almost every day. The primary raw material for any leather pro-
cessing industry is derived from slaughter houses and waste from the meat
industry. This raw material is processed and converted into usable leather
in tanneries. Hence, tanning industry is considered as one of the primary
leather processing units in the entire leather industry [3].
Although the leather tanning industry primarily utilizes the waste from
the meat industry, it also involves the usage of many chemicals to convert
the raw material into finished product. Thus, leather industry consumes re-
sources and produces pollutants which are toxic and hazardous to the envi-
ronment. For instance, in leather processing one metric ton of raw material
is converted into only 200 kg of usable leather product (comprising 3 kg of
chromium). The solid and liquid waste includes about 250 kg of nontanned
solid waste, 200 kg of tanned waste (comprising 3 kg of chromium), and
50,000 kg of wastewater effluent (comprising 5 kg of chromium). Altogether,
one metric ton of raw material yields only 20% as finished leather product

Energy from Toxic Organic Waste for Heat and Power Generation © 2019 Elsevier Ltd.
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