The document discusses eco-friendly textile processing methods under the guidance of Prof. M.D. Teli, emphasizing the removal of impurities and enhancing fabric quality through various techniques such as enzymatic desizing, bio-scouring, and ozone bleaching. It outlines the advantages of using enzymes and alternative materials for reducing environmental impacts while detailing procedures for effective processing. The conclusion highlights the urgent need for the textile industry to adopt sustainable practices amid increasing environmental regulations.

1. The
Presentation
On
“ECO FRIENDLY TEXTILE PROCESSING”
UNDER THE GUIDANCE OF
Prof. (Dr.) M.D.TELI
BY
Omkar S. Parmaj
Alemayehu Leta

2. A good preparatory process has several objectives
•Removal of loose hairy protruding fibres from the surface of the
fabric to give a smooth, even and clean looking face.
•Removal of natural impurities like oils, fats, waxes,
greases, natural matter, lignin and sizing material
like starches.
•To obtain an absorbent fabric,this is ready
for dyeing or printing process.
•To obtain softer and proper white fabric,
depending on its application.

3. Singeing Desizing Scouring and Bleaching
MerserizationDyeingFinishing

4. The process of singeing is carried out for the
purpose of removing the loose hairy fibres
protruding from the surface of the cloth, thereby
giving it a smooth, even and clean looking face.
Objective if singeing machine
•Removing of protruding fibre
•Improving luster
•Reduce dyeing and printing problem
Types of singeing process
1. Plate singeing machine
2. Rotary-cylinder singeing machine
3. Gas singeing machine

5. •Material ofburner: metal replaced by ceramic.
•Composition of gas fuel: air to petroleum chemical
ratio
•Fabric is pre heated to remove the moisture.
•Water cooling system is incorporated just behind
the ceramic material to control the temperature of
ceramic material.
•in case of power failure, both burners tilt away
from the fabric simultaneously.
•Fabric passing path is variable for maintaining
contact angle for different kind of fabric.

6. Eco friendly pre-treatment
Enzymes are a class of proteins that function as biocatalysts which
are biodegradable, very specific in action and are used in small
quantities. They are made up of 200-250 amino acids. They work
by lowering the activation energy of the reaction making it much
faster.
• They are produced by living organisms such as fungi or
bacteria.
• Enzymes are complex organic, soluble bio-catalysts, formed by
living organisms that catalyze chemical reaction in biological
processes.
• Enzymes are quite specific in their action on a particular
substance.

7. Enzyme Effect
Amylase Desizing (to decompose starches applied in sizing)
Catalase Act on H2O2 to decompose it into water & oxygen
Proteases, lipases and pectinases When combined, act on proteins, pectin and natural
waxes to effect scouring
Laccases Decomposes indigo molecules for wash-down effect on
denim
Cellulases Break down cellulosic chains to remove protruding fibres
by degrading &create wash-down effect by surface
etching on denims etc.
Cellulases and Hemicellulases Bio stoning of jeans
Desizing of CMC
Stylish effect on cellulose fibres
Pectinases Breaks down pectin in scouring
Proteases Scouring of animal fibres, degumming of silk and
modification of wool properties
Lipases Elimination of natural triglycerides (in scouring) or
present in desizing (tallow compounds)

8. E + S → E S → P + E
(Enzyme) (Substrate) (Enzyme-Substrate) (Product) (Enzyme)
Substrate entering
In active side of
enzyme
Enzyme
substrate
complex
Enzyme/substrate
complex
Prodcut release from
enzyme

9. The removing of size material which incorporated in pre-weaving process is known
as desizing.

10. There are three main advanced desizing method are
1. Enzymatic desizing
2. Solvant desizing
3. Atmospheric plasma desizing

11. •Amylases are the enzyme that hydrolyses and reduces the molecular
weight of cellulose.
hydrolyze starch molecules to give diverse products.
specific for starch, removing it without damaging to the support
fabric.
optimum temperature is 30-60°C, optimum pH is 5.5-6.5.

12. Cont…
Enzymatic desizing and utilisation of desizing liquor for H2O2
 To utilize desizing baths for bleaching in which glucose oxidase
enzymes generate hydrogen peroxide and gluconic acid using glucose as
a substrate.
 Amyloglucosidases are enzymes used in desizing to degrade starch
until it becomes glucose.
 Optimum conditions are 0.75% (o.w.f.) enzyme, pH 4.1, 62 °C and a
process time of 45 minutes.
Advantages:
 reducing the use of peroxide stabilizing agents with the help of gluconic
acid
 saving water and energy by using desizing liquor for bleach.

13. • Some solvent are used for desizing of textile substrate.
• Sonafab 1000). It is a unique Desizing Agent, having
excellent solvent and emulsifying action on all types of
stain. (Sonal Dye-ChemPvt. Ltd)
Perchloroethylene -- desizing solvent

15. •It is a very clean operation with no disposal problem, the
pollution effect is negligible.
•The time of desizing and floor area for the machinery is far less
than for conventional system.
•Due to quick and even solvent penetration the size removal is
more uniform.
•The solvents are recoverable and have less or no effluent load.
•This method is useful since energy consumption is low, time of
desizing is low.
•Acrylic and wool fabrics develop a lustrous, soft hand in solvent
without any felting.
•When solvent desizing is followed by bleaching, the caustic
scouring is omitted since pectin and wax

16. DISADVANTAGE OF SOLVENT DESIZING
•Although solvent desizing ranges are available
commercially, the price of the equipment is high.
• The majority of size systems used in aqueous process is
not readily applicable in solvent desizing.
•Cost of processing is higher than for water base process.

17. • Plasma is four states of matter
• Here material having in ionized condition
• Plasma is produce by applying electric field
on a gas
• Plasma is etching the fabric surface
• Etching is depend upon the voltage, type of
gas, time

18. Ultrasonic energy are the high frequency waves rangeing from 20Khz to 50Mhz which is
nnot audiable by human
• In liquids, longitudinal vibrations of molecules generate compression and
rarefaction, i.e., areas of high pressure and low local pressure
• The latter gives rise to cavities or bubbles, which expand and finally during the
compression phase, collapse violently generating shock waves.
• The phenomena of bubble formation and collapse (known as cavitation) is generally
considered responsible for most of ultrasonic physical and chemical effects observed
in solid/liquid or, liquid/liquid systems.

19. Use of ultrasonic energy in
desizing
Amylase - 0.75 g/l
wetting agent - o.5 g/l
Temperature - 55°C
Time - 20 min.
Desizing efficiency 7 when US is
used.
Desizing efficiency 2.5 when US is
not used.
•Energy savings resulting from lower
process temperatures and shorter cycle
times
• Reduced consumption of dyes and
chemicals, which allows for a 20-30%
reduction in the amount of effluent
• Water savings of around 20%
• Improvement in product quality
• Increased productivity because of shorter
cycle times
Limitation
•This process requires some assistance from temperature. This process does not
involve complete elimination of temperature.
Recipe Advantage

20.  To remove natural as well as added impurities of essential hydrophobic
character(oil,fat,waxes) as completely as possible and leave the fabric in high
absorptive condition without undergoing significant chemical or physical
damage
 To make the goods suitable for removing the natural colouring matter of
the cotton during the subsequent bleaching process.
Conventional method: Alkali scouring.
Where 3-4% caustic soda is used at high temperature (90-95oC) for long
duration (2-3hours)
Disadvantages of alkali scouring:
1) Damage to fibre.
2) Requirement of large quantity of water for washing.
3) Heavy effluent load (Salts of neutralization)

21. Enzymatic Scouring or Bio-Scouring can simply be defined as the
application of living organisms and their components to remove
the natural and added impurities.
Enzymes used for Bio scouring
Pectinase – (Pectins removal)
Protease – (Removal of proteins)
Combination of 2 or 3 enzymes
may be used to get synergistic effect.
Conventional scouring requires high temperatures and high
consumption of chemicals. Suppliers.

22. Parameter Bio Scouring Alkaline Scouring
pH 7-8 12-13
Temperature 50-600C 950C
Residual Pectin 20-25% 10-11%
Weight loss <1.5% 4-6%
Handle Very soft Harsh and papery
Rinse Water
Consumption
30-40% of Alkaline scouring
TDS 50% of Alkaline Scouring
BOD 50% of Alkaline Scouring
COD 50% of Alkaline Scouring

24. Advantages of bi-scouring
(BOD) and (COD) of enzymatic scouring process are 50 % as compared to
alkaline scouring (100 %). Total Dissolved Solid (TDS) of enzymatic scouring
process is 50% as compared to alkaline scouring (100%).
Handle is very soft in enzymatic scouring.
It also minimises health risks of operators as they are not exposed to hazardous
chemicals.
reduced water and wastewater costs, reduced treatment time and lower
energy consumption because of lower treatment temperature (the optimal
temperature is from 40 to 60°C) .

25. Limitation of Bio scouring process
•The enzymes used for scouring are costly and they require temperature for their
action.
•The increase in temperature or pH may deactivate the enzyme which may alter the
process efficiency.

26. BLEACHING
Bleaching is to decolourise natural pigments and to confer a pure white
appearance to the fibres. The most common industrial bleaching agent is
hydrogen peroxide, which is usually applied at alkaline pH and
temperatures close to boiling.

27. BIO BLEACHING
Enzymes can also be used in bleaching.
Glucose oxidase
 Glucose oxidases (GODs) are flavoproteins with a Flavin-adenine-
dinucleotide (FAD) active site.
The enzyme is highly specific for B-D-glucose and catalyses the following
reaction for hydrogen peroxide generation.
 Ph - 4.5-7
 temperatures - 40°C

28. Cont….
• Gluconic acid acts as bleach stabilizer
• it would allow for the reuse of sugar contaminated effluent
from other wet processing steps (desizing bath containing
glucose)
The actual bleaching process involves 2 steps:
• Peroxide generation by GOD at the enzyme optimum
conditions.
• PH adjustment to 7.5-8 and bleaching process at 85-90°C for
60-120 minutes with the enzymatically hydrogen peroxide.

29. Cont…
Laccase
Laccase (EC 1.10.3.2) is a multi-copper oxidase enzyme which
oxidizes a broad range of aromatic compounds as substrates and
oxygen as a terminal electron acceptor.
Rapid bleaching with laccase–hydrogen peroxide enhances the
whiteness of cotton fabrics.
Bleach clean-up
 Traditional method:
Bleach --> Rinse --> Rinse --> Rinse --> Dye
 There are two methods for bleach clean-up
• After completion of the process the bleached liquor was drained out,
then the fabric was rinsed with water a number of times to remove
the H2O2 from the bleached fabric.
• use of a mild reducing agent to neutralise the bleach.

30. Cont…
 Catalase have been used to decompose residual hydrogen
peroxide in fabric prior to dyeing
 Catalase enzyme catalyzes the decomposition of hydrogen
peroxide to water and oxygen. One catalase molecule can
convert millions of molecules of hydrogen peroxide to
water and oxygen each second
 Use of Catalase enzyme made it possible to reduce the
temperature and volume of the second wash after
bleaching from 80-950C to 30-400C, resulting in a 9-14%
saving of energy, a 17-18% saving of water and an overall
cost saving of 9%

31. OZONE BLEACHING
 Industrial production of ozone can be accomplished by applying a plasma
discharge to oxygen in air.
 Ozone is a natural substance and it is a strong oxidising agent and it
decomposes rapidly.
Process
Fabric having 24% moisture content is placed
in application chamber and exposed to 100
g/m of concentration of ozone oxygen gas
mixture.
pH – 5 with acetic acid
Time – 1-7 min
Temperature- 30°C

32. ADVANTAGES AND LIMITATION OF OZONE
BLEACHING
Advantages
The quality of the processed
fabric is comparable.
Grey preparation with ozone
can be completed in one or two
minute.
This process has additional
advantages such as savings in
thermal energy, water and
chemicals
Limitations
 The yield of ozone generator is
low (6-12% from oxygen and 4-
6% from air), and ozone
concentration is low as well.
 Ozone has to be generated on-
site because its problems to be
stored and transported.
 Energy consumption for
production of O3: Based on pure
oxygen, the costs will be 6 to 15
kWh/kg O3.

33. PER ACETIC ACID BLEACHING
• Per acetic acid is also known as peroxyacetic acid.
• It is colorless in nature.
• It is miscible with water and most of organic solvents.
• It is very powerful oxidizing agent.
• It is also used as germicide for protecting fruits/vegetables against spoilage.
• General formula is C2H4O3.
• It corresponds to acetic acid with additional oxygen atom per molecule.
i.e. CH3COOOH (peracetic acid)
• It is highly unstable at pH 5-5.5. But stable at lower pH of 1.5-2.
• A concentration of 35% to 40% is dangerously explosive.

34. Mechanism of oxidation with peracetic acid, it gives extra
oxygen atom and acetic acid is formed as co-product.
CH3COOH CH3COOH + [O]
Procedure for bleaching with peracetic acid:
1) Peracetic acid being unstable has to be prepared before bleaching being
carried out as per above procedure.
2) Bleaching is carried out with
MECHANISM OF PERACETIC ACID

35. LIQUID AMMONIA MERCERIZATION
 In this technique the fabric is first passed through drying cylinders to reduce the
moisture content of fabric then through a cooling station.
 Afterwards it is impregnated with liquid ammonia in a closed chamber and then
the fabric is passed through felt calendars in which 90-95% of ammonia is removed.
Advantages over alkali mercerization:
Quick process
Low shrinkage post washing
Superior in the degree of improvement in strength
 Durability of dimension stability
Soft handle

36. LIQUID AMMONIA MERCERIZATION

37.  Rapid changes in technology a dire need to
conserve water and energy have forced the textile
industry to give up the old conventional processes
and try out new methods
 All over the world, the environmental regulations
are becoming more and more stringent and are
forcing the shift of technology towards less polluting
or non-polluting areas of technological development.
 To go towards the eco friendly and sustainable textile
processing, New technology has to be incorporated in
the textile processing
CONCLUSION