Water Footprint in Leather Tanning and Steel Production
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in Mediterranean countries. For instance, due to the increase of population and the
uttermost urbanization in countries, the current trade presently outpacing US$ 80
billion in a year and will increase in a few years. Slaughterhouses and waste from
the meat industry are the primary raw material used during the leather processing
industry. In common tanneries, leather processing involves many steps, with the
use of various chemical and mechanical processes to transform hides and skins into
higher valuable material through the tanning process.
The tanning process can be defined as a conversion of raw hides and skin of
animals into a stable, flexible, useful, and desirable material suitable for a wide
range of applications. Although recent studies have revealed different phases of this
process [7], most of the authors conversely suggest three broad processes classified
into the Preparatory or beam house stage, tanning, and post-tanning operations.
3 Beam House Stage Activities
Many operations are involved in this first to make the hide/skin ready for tanning.
Although many pretreatment options exist, the most common may include the
following:
Preservation
In this operation, untanned hides are directly prepared for tanning or preserved by
curring (to prevent putrefaction of the protein substance from bacterial growth),
salting, and freezing. This treatment is therefore useful to protect animal skin from
any decomposition.
Soaking
Due to the high content of salt used in the previous step, the soaking consists in
to remove the absorbed salt, bring the hides and skins back to their initial condition, rehydrate and wash the skin, and finally remove unwanted materials such as
blood, manure, urine, dung, dirt, and interfibrillar proteins for subsequent processing.
During this step, major raw material need 6,000–9,000 L water/t hide to be clean up.
Green Fleshing
This step stands for mechanical removal of fats and flesh from the inside of skins
or hides. Based on the environmental concept, green fleshing is operated when the
tissue is not contaminated with chemicals, then the number of chemicals required
for the next process will be reduced.
Liming
The liming is performed in two stages. The first called dehairing operation concerned
the mechanical removal of wool and flesh. The second step designated as reliming
consists of the diffusion of chemicals in the hide matrix of consecutive operations for
further elimination of protein and opening-up process. The hides are finally fleshed to
139
in Mediterranean countries. For instance, due to the increase of population and the
uttermost urbanization in countries, the current trade presently outpacing US$ 80
billion in a year and will increase in a few years. Slaughterhouses and waste from
the meat industry are the primary raw material used during the leather processing
industry. In common tanneries, leather processing involves many steps, with the
use of various chemical and mechanical processes to transform hides and skins into
higher valuable material through the tanning process.
The tanning process can be defined as a conversion of raw hides and skin of
animals into a stable, flexible, useful, and desirable material suitable for a wide
range of applications. Although recent studies have revealed different phases of this
process [7], most of the authors conversely suggest three broad processes classified
into the Preparatory or beam house stage, tanning, and post-tanning operations.
3 Beam House Stage Activities
Many operations are involved in this first to make the hide/skin ready for tanning.
Although many pretreatment options exist, the most common may include the
following:
Preservation
In this operation, untanned hides are directly prepared for tanning or preserved by
curring (to prevent putrefaction of the protein substance from bacterial growth),
salting, and freezing. This treatment is therefore useful to protect animal skin from
any decomposition.
Soaking
Due to the high content of salt used in the previous step, the soaking consists in
to remove the absorbed salt, bring the hides and skins back to their initial condition, rehydrate and wash the skin, and finally remove unwanted materials such as
blood, manure, urine, dung, dirt, and interfibrillar proteins for subsequent processing.
During this step, major raw material need 6,000–9,000 L water/t hide to be clean up.
Green Fleshing
This step stands for mechanical removal of fats and flesh from the inside of skins
or hides. Based on the environmental concept, green fleshing is operated when the
tissue is not contaminated with chemicals, then the number of chemicals required
for the next process will be reduced.
Liming
The liming is performed in two stages. The first called dehairing operation concerned
the mechanical removal of wool and flesh. The second step designated as reliming
consists of the diffusion of chemicals in the hide matrix of consecutive operations for
further elimination of protein and opening-up process. The hides are finally fleshed to