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16.2.3.2 Production Process in the Fashion Industry
16.2.3.2.1 Wet-Treatment
Chemical use and water consumption in the production process are two of the most
harmful environmental impacts of the fashion industry. Evidence shows that for
approximately every tonne of textile produced, 200 tonnes of water are needed for
dyeing, washing, printing, desizing, scouring, bleaching, mercerizing and the fabric
finishing processes. All these processes comprise the wet-treatment phase
(Choudhury 2017). For example, the production of a t-shirt requires approximately
2650 litres of water. Nearly 20% of this water is used for dyeing process (Lakshmanan
and Raghavendran 2017). In order to reduce the water footprint of textile products,
the industry has engaged in various technologies throughout the wet- treatment process, such as the use of plasma, ultrasonic-assisted dyeing and the use of supercritical carbon dioxide. These innovations reduce water use significantly and save
energy in the wet-treatment process.
Plasma technology, for example, works at a low temperature and reduces the use
of chemicals. After going through plasma polymerization, the chemicals lay on the
textile surface. This process allows the fabric’s internal structure to remain unaffected (Lakshmanan and Raghavendran 2017). Dyeing and finishing processes can
be done by plasma gas particles, facilitating the modification of the fabric and
improving textile characteristics and functionality. Plasma technology and
ultrasonic- assisted dyeing technology can be applied to wool, cotton and polyester
fabrics during the dry stage. These methods significantly diminish the use of huge
quantities of sodium chloride, decreasing the discharges of dyestuff and other
chemicals into wastewater (Lakshmanan and Raghavendran 2017).
The supercritical carbon dioxide method for dyeing synthetic fibres also reduces
consumption of both water and energy. Through increasing temperature and pressure, it generates a liquid-gaseous state that produces supercritical fluids. Fabric or
fibres are put inside an autoclave with dye powder, then purged with carbon dioxide
(CO2) and finally preheated. Carbon dioxide is non-toxic and non-flammable and
can be recycled in a closed system (Lakshmanan and Raghavendran 2017). A case
in point is the DyeCoo textile, the “world’s first water-free and chemical-free dyeing
solution”. The CO2 is reclaimed and has a recycling efficiency of 95%
(DyeCoo 2018).
16.2.3.2.2 Green Chemistry
The discharge of harmful substances during the wet-treatment process is another
major problem confronting the fashion industry. Some corporations have engaged
in solutions to tackle this issue, including Adidas, Gap, H&M, Nike, Puma,
Taiwanese dyestuffs makers and Everlight Chemical, which committed to Zero
Discharge of Hazardous Chemicals by 2020 (ZDHC) (Choudhury 2017). Two processes can reduce the discharge of chemicals into water streams: recycling and use
C. Arana et al.
16.2.3.2 Production Process in the Fashion Industry
16.2.3.2.1 Wet-Treatment
Chemical use and water consumption in the production process are two of the most
harmful environmental impacts of the fashion industry. Evidence shows that for
approximately every tonne of textile produced, 200 tonnes of water are needed for
dyeing, washing, printing, desizing, scouring, bleaching, mercerizing and the fabric
finishing processes. All these processes comprise the wet-treatment phase
(Choudhury 2017). For example, the production of a t-shirt requires approximately
2650 litres of water. Nearly 20% of this water is used for dyeing process (Lakshmanan
and Raghavendran 2017). In order to reduce the water footprint of textile products,
the industry has engaged in various technologies throughout the wet- treatment process, such as the use of plasma, ultrasonic-assisted dyeing and the use of supercritical carbon dioxide. These innovations reduce water use significantly and save
energy in the wet-treatment process.
Plasma technology, for example, works at a low temperature and reduces the use
of chemicals. After going through plasma polymerization, the chemicals lay on the
textile surface. This process allows the fabric’s internal structure to remain unaffected (Lakshmanan and Raghavendran 2017). Dyeing and finishing processes can
be done by plasma gas particles, facilitating the modification of the fabric and
improving textile characteristics and functionality. Plasma technology and
ultrasonic- assisted dyeing technology can be applied to wool, cotton and polyester
fabrics during the dry stage. These methods significantly diminish the use of huge
quantities of sodium chloride, decreasing the discharges of dyestuff and other
chemicals into wastewater (Lakshmanan and Raghavendran 2017).
The supercritical carbon dioxide method for dyeing synthetic fibres also reduces
consumption of both water and energy. Through increasing temperature and pressure, it generates a liquid-gaseous state that produces supercritical fluids. Fabric or
fibres are put inside an autoclave with dye powder, then purged with carbon dioxide
(CO2) and finally preheated. Carbon dioxide is non-toxic and non-flammable and
can be recycled in a closed system (Lakshmanan and Raghavendran 2017). A case
in point is the DyeCoo textile, the “world’s first water-free and chemical-free dyeing
solution”. The CO2 is reclaimed and has a recycling efficiency of 95%
(DyeCoo 2018).
16.2.3.2.2 Green Chemistry
The discharge of harmful substances during the wet-treatment process is another
major problem confronting the fashion industry. Some corporations have engaged
in solutions to tackle this issue, including Adidas, Gap, H&M, Nike, Puma,
Taiwanese dyestuffs makers and Everlight Chemical, which committed to Zero
Discharge of Hazardous Chemicals by 2020 (ZDHC) (Choudhury 2017). Two processes can reduce the discharge of chemicals into water streams: recycling and use
C. Arana et al.