technology of eco-friendly textile processing

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Transcript technology of eco-friendly textile processing

TECHNOLOGY OF ECO-FRIENDLY TEXTILE
PROCESSING- A ROUTE TO SUSTAINABILTY
KEYNOTE PRESENTED BY
Asif Muhammad Sami
BSc. Textile Engg, MBA, CText (ATI), Fellow- IEB, Textile Consultant
CEO- EuroAsiatic Resources, Chairman - S S Vision Ltd &
Textile Consultant - Perseus Ltd.
Cell: 01819213971, email: [email protected]
ABSTRACTS:

Textile Project like eco-friendly or green project must be
designed for sustainable green factory building concept
also textile raw materials , dyes & chemicals, textile
processes all should be based on 3R (reduce-recyclereuse) concept.

The processing of textiles should be cost effective and
environment-friendly. Innovative and efficient strategies
to achieve these goals are needed. This paper reports
various problems in different stages of processing
textile materials and their “green solutions” the
alternatives by which the problems can be avoided
through innovative techniques and various measures of
textile cleaner production”(CP) which ensures textile
processing “eco-friendly”, “cost effective” and
“sustainable business”.
ECO FRIENDLY / GREEN TEXTILES CONCEPT

The project factory building should be designed on go green
concept.
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Textile raw materials are processed in eco-friendly manner
and certified by GOTS etc.
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Dyes and chemicals should be OKEOTEX certified standard.
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Textile processing right from Raw fiber, Yarn manufacturing,
Weaving/knitting, wet processing, finishing processes all
should be maintained using eco- friendly technology.
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Textile waste water should be treated considering basis of 3R
(reduce- recycled & re-use ) concept.
ECO- FRIENDLY TEXTILES PROCESSING CONCEPT
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Textile Cleaner Production (CP) like Water saving, energy
savings using all possible methods.
Re-use of textile waste, recycled & re-use of waste water,
recovering and re-using salt, re-use of waste heat energy.
Carbon emission control
Environmental sustainability care for the environmentInfluence the supply chain to use sustainable
processes/method.
Operate business in environmental friendly way.
Work to conserve water, energy and reduce / recycle waste.
Sustainable design approach – explore the use sustainable
materials and products.
NEED FOR ECO- FRIENDLY & RECYCLABLE +
RE-USABLE TEXTILES:
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Concerns related to textile industries areTextiles production and processing- chemical intensive
applications
Associated social and environmental concerns
GROWING CONCERNS-
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Increasing industrial pollution
Industrial waste disposal problems
Economic and social health of the farmers and industrial
workers.
Unawareness about socially responsible business structures
are required.
ENERGY SAVING GREEN FACTORY BUILDING SHED:
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Using insulation of building walls, floor & ceiling.
Replace old windows which are bad thermal insulators.
Make the building shell as air tight as possible.
Install heat exchange for proper ventilation.
Roof of sunny side should use collects solar energy.
Heavily frequented door should have automatically closing
system.
Light from shaded side yields natural light but not heat.
New building using geothermal energy exchange.
Use of insulation of all steam pipe and wire duct.
Using rain water for garden irrigation, technical use or as
toilet flash water.
WHY WE ALL NEED TO BE CONCERN ABOUT ECOFRIENDLY (GREEN) PROCESSING IN TEXTILES:
Textiles /Garment industry is contributing to the global warming
& pollution from the stages like  Cultivation of the fibres
 Yarn manufacture
 Fabric manufacture
 wet processing
 Manufacturing of the garment
 Transportation to customers
 Usage and disposal
STAGE 1: RAW MATERIALS (FIBER)
CONTRIBUTORS TO CARBON FOOTPRINT
 Cotton cultivation requires large amount of pesticides,
fertilizers and water.
 Approximately 257 gallons of water is required for only one tshirt.
ECO-FRIENDLY OR GREEN SOLUTIONS:
 ORGANIC COTTON is “GREEN” fabric.
 It is grown - where synthetic chemical pesticides, fertilizers
and genetically modified organisms are avoided.
 Organic fertilizers such as Neem or Garlic extract are used.
ECO-FRIENDLY OR GREEN SOLUTIONS
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Substitute cotton for other natural eco- friendly materials like
hemp, wool, organic cotton, soy silk, bamboo fabrics ,jute,
corn fibre etc having without any harmful effects of chemicals
or toxics.
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Synthetic fabrics such as polyesters are –
- Easy care and more durable alternative to natural fabrics.
- These are more energy intensive in production, but these
fibers need to be washed at lower temperatures thus saving
a lot of energy throughout their life cycle.
ECO-FRIENDLY OR GREEN SOLUTIONS
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Cellulose based fibres like viscose can be used.
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There are now developments of new fibres of natural origin like
Tencel (Lyocell) made from wood.
EXAMPLES OF SOME ECO-FRIENDLY FIBERS :
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Organic Cotton, Organic wool, Organic Silk, Organic Jute etc
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Manmade fibers like corn/Soya bean, Pineapple, Banana leaf, Lyocell
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Recycled fibers like Recycled Cotton, Recycled Polyester
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Natural fiber like colored Raw Cotton
ORGANIC COTTON – A SUSTAINABLE ALTERNATIVES
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SOCIAL AND ENVIRONMENTAL BENEFITS
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Organic Cotton helps in pollution control, improving soil
fertility.
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Organic cotton farming helps in preventing contamination of
water, soil & air.
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Apart from using in all diversified products, organic cotton
also suitable for baby products, apparels, hygiene and care
products like cotton balls, ear buds, sanitary pads, medical
textiles, cosmetics bags etc.
RECYCLED COTTON;
RECYCLED COTTON is nothing but made from recovered
cotton that would otherwise be cast off during either spinning,
weaving, knitting or garment cutting process.
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THE DISCARDED COTTON WASTE from above mentioned
process are collected , shredded into small fibers and
processed once again into yarns and fabrics in cost effective
method.
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RECYCLED COTTON is also known as eco friendly choice in
clothing fashion industry.
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COTTON WASTE RE-CYCLING PROCESS involves no
chemical addition rather it helps in generating employment
and better positive impact in the environment (clean
production).
RECYCLED POLYESTER (PET):
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Polyester is one the most non-biodegradable polymer which
creates environmental problems.
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Wellman inc. Introduced in 1993 as the first polyester textile
fiber made from post consumer pet packaging.
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Recycled pet is used in diversified products like backpacks and
blankets, t-shirts, sportswear, soft luggage and socks etc.
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Eco friendly recycled pet is certified by OEKOTEX and SGS
etc.
STAGE 2: YARN FABRICATION AND FABRIC
MANUFACTURE
Contributors to carbon footprint
 There are many stages required to process cotton from fibre
to fabrics the fibre are cleaned, carded (combed) spun into
yarn, coated with starches or chemicals, woven or knitted
into fabrics,
CONTRIBUTORS TO CARBON FOOTPRINT & GREEN
SOLUTION
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In sizing process , starch is used in sticky paste form to
yarn to enhance its strength and its abrasion resistance. The
starch paste consists of preservative in order to protect it from
the stains get formed on the fabrics surface.
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Some preservatives like penta-chloro phenol that are toxic
effect on human skin, should be avoided by utilizing a
synthetic starch decreasing the health hazards.
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Use oil stain remover during the weaving operations before
textile wet process so that oil stains do not get formed.
PROCESS INVOLVED
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FIBRE PREPARATION
YARN SPINNING
CONTRIBUTION TO
POLLUTIONS
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Fiber waste,
Packaging waste,
packaging waste, sized
yarn, fiber waste,
cleaning and processing
waste
PROCESS INVOLVED
CONTRIBUTION TO POLLUTIONS
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SLASHING/SIZING
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Fiber lint, yarn waste, unused
starch based sizes, water with
high level of BOD, COD
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WEAVING
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Packaging waste, yarn waste
and fabric scraps, used oil.
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KNITTING
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Waste yarn and fabric scraps
packaging
WASTE YARN AND FABRIC SCRAPS PACKAGING
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Textile processing industry requires huge volume of water ,
energy & various chemicals for Desizing, Scouring,
Mercerization, dyeing, printing and finishing stage.
Textile industry, backbone of fashion garments, is large
variation in demand of type, pattern & color of fabric resulting
into significant fluctuation in waste generation.
Textile processing generates much waste steam, including
liquid gaseous and solid wastes, some of which may be
hazardous.
Wet processing creates the highest volume of waste water.
Textile finishing represents the most variable area in the
production process. A wide and ever-growing range of finishes
are now available that either improves the properties, handle or
texture of the fabric.
TEXTILE WET PROCESSING- VITAL ENVIRONMENTAL
ISSUE
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Some important environmental concerns related to textile
wet processing;
Intensive chemical based wet processing like scouring,
bleaching, mercerizing, dyeing, printing etc
 Heavy metals like iron, lead, copper etc consist in
dyestuffs auxiliaries, binders etc.
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Residual dyestuffs, chemicals in water: due to poor
dye fixation with fiber.
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PVC and Phathalets: used in Plastisol printing paste
and colorant fixatives.
Formaldehyde: found in dispersing agents, printing
paste and colorant fixatives.
 Dye effluent-wastewater issue.
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CONTRIBUTORS TO CARBON FOOTPRINT
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The conventional preparation process of Desizing, Scouring
and Bleaching with their related wash-off stages, produces
heavy BOD in effluents.
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Chlorine used in bleaching creates halogenated organic
substances, of which some are suspected to be carcinogenic
e.G.., Chloroform thus is not preferred.
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Use of banned amines and toxic dyes, banned amines are
the chemicals which are released from some of the azo dyes
on reductive cleavage. These are suspected to be
carcinogenic and being banned.
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Carriers ( disperse dyes) and solvents may be emitted
during dyeing operations may lead to volatilization of aqueous
CONTRIBUTORS TO CARBON FOOTPRINT
hemical emulsions during heat setting, drying or curing process, thus
creating harmful volatile organic compounds.
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Acetic acid and Formaldehyde are two major emissions of concern in
textiles.
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Textile mills usually generate Nitrogen and Sulphur oxides from boilers.
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Significant sources of air emissions in textile operations -Resin finishing
and dyeing operations, printing, fabric preparation and waste water
treatment plants hydrocarbons are emitted .These processes can emit
formaldehyde, acids, softeners and other volatile compounds.
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Wool industry used chlorine based compounds for anti-shrinking
dealing and such practice also generates toxic effluents.
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Oxalic Acid is used for removing rust stains before bleaching. The
oxalic acid is lethal aquatic organisms and increase COD & BOD to a
significant level.
TEXTILE PROCESSES
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SIZING
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DESIZING
CONTRIBUTION TO POLLUTION
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Penta-chloro phenol as anti
mildew agent
Voc’s from glycol esters
SCOURING
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Emulsifying agents like nonyl
phenyl ethyloxylates, chloroform
as scoring assistance.
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Hypochlorite (chlorine bleaching)
products like chlorine dioxide
BLEACHING
TEXTILE PROCESSES
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DYEING & PRINTING
CONTRIBUTION TO POLLUTIONS
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Azo dyes containing
carcinogenic amines
CDFA based on formaldehydes
dyes containing heavy metals
such as Iron, Zinc etc
Formaldehyde as mordant
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Formaldehyde fixer/binder in
pigment printing
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Formaldehyde as cross linker
FINISHING
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Reactive softener
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metal fluorides, DDT, and other
anti bacterial materials
containing metals in rot proofing.
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Amides like melamine amides in
water repellent
ECO-FRIENDLY OR GREEN SOLUTIONS:
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Dyes made from natural pigments and soymilk used as
binding agent and sizing agent makes the whole dyeing gentler
on the environment.
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Dyes that forms carcinogenic amines on reduction and thus
increase bod/cod need to be avoided.
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Where possible, use high fastness direct dyes having 90%
upto 99% exhaustion rate should be chosen instead of using
reactive dyes which having low exhaustion rate 65%-75% to
reduce dyeing cost as well as etp running cost.
Usage of Hydrol as a substitute of sodium sulphide is
recommended for sulphur dyeing.
low salt
 Dyeing process requires more salt for exhaustion. So usage
dyes may be used.
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ECO-FRIENDLY OR GREEN SOLUTIONS:
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An integrated chemical pre-treatment (single bath
process)
i.e. Combined Desizing, Scouring, Bleaching is
recommended to reduce the water, chemical consumption
and also energy.
Fabrics to be dyed with deeper shades may not be bleached.
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In case of dyeing and printing toxic chemicals may be
avoided.
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Formaldehyde free resins and finishing chemicals may be
used for finishing.
SUSTAINABLE PROCESSING OF TEXTILES:
EXPLORE INTO BIO PROCESSING OF TEXTILES Bio-processing can simply be defined as the applicant of living
organisms and their components to industrial products and
processes, which are mainly based on enzymes. Like
Enzymatic Desizing- by using Amylase bacteria.
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Enzymatic bio scouring ( by using lipase/cellulase enzyme)saves water by 30% and energy upto 60%, less fabric weight loss &
strength loss, better fabric quality and enhanced color brightness
after dyeing & low TDS in discharge.
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Enzymatic bleaching – (Catalases/laccases for removal of H2O2)
saves water, energy, shorten bleaching process cycle, eco friendly
process and consistent bleaching result, saves chemicals.
* Bio polishing and Eznymatic based softeners (Cellulase) etcenzymatic bio-finishing yields a cleaner surface, softer hand-feel,
reduces pilling and increases luster.
EXPLORE INTO BIO PROCESSING OF TEXTILES -
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BIO-STONE WASHING (DENIM FINISHING) – Using a special
cellulase enzyme instead of pumic stones. Cellulase works
by loosening the indigo dye on the denim in a process known
as ‘bio-stonewashing’. A small dose of enzyme can replace
several kilograms of pumice stones. The use of less pumice
stones results in less damage to garment, machine and less
pumice dust in the laundry environment; in addition, it’s
possible to fade denim without risk of damaging the garment.
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DECOLORIZATION OF DYE HOUSE EFFLUENT BY ENZYME:
Laccase enzymse produced from fungi like Trametes Modesta
or Trametes Versicolo etc as Fungi are used for dye
decolourization in effluent treatment which is major factor for
environmental issue.
ECO-FRIENDLY OR GREEN SOLUTIONS:
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ECO-FRIENDLY SUPLHUR DYEING METHOD: Since sulphur dyes
as single dyes alone consumption 20%-25% for cotton dyeing
in the world. Using eco-friendly thioria di-oxide or indirect
cathodic reduction/electrolysis method ( although relative
expensive than traditional method) avoiding traditional sodium
sulphide can save dyes consumption.
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ECOFRIENDLY REACTIVE DYEING: Various environmental
problems encountered in reacting such as high levels salt &
high color concentration ( unfixed dyes) in effluent with huge
volume of water consumed.Reactive dyes poor fixation of
ranging 10%-40% dyestuff hydrolysed goes down drain which
is aesthetically unpleasant, blocks sunlight, algae
overpopulate, reduction in o2 levels in water, suffocation of
flora and fauna in water courses. Therefore, water effluent
treatment plant is now becoming prime consideration by the
industry and equally important as the production of textile
product itself.
ECO-FRIENDLY OR GREEN SOLUTIONS:
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Significant amount of water consumption, energy
consumption, dyeing cost and effluent load can minimized
by using either cationic surfactants ( instead of salts) Or
dyes with high exhaustion rate 90%-99% ( preferably direct
dyes) instead of reactive dyes with low exhaustion rate 60%80%)
As a result of being cationic (instead of anionic) pretreated
cotton, the number advantages recorded such as:
No requirement for salt
Nucleophiles in polymer more reactive than hydroxyl roups in
fibre.
Neutral ph of application
Hydrolysis minimised
Colour fixation yield maximised
Colour fixation yield maximised
Less colour in effluent
ECO-FRIENDLY OR GREEN SOLUTIONS:
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Less wash-off requirement
Significant reduction in operation time
Significant reduction in water consumption
DEGREE OF FIXATION OF DIFFERENT DYES ON FIBER
ARE FOLLOWS:
DYES----------- FIBER----------%FIXATION ----%LOSS IN ETP
 ACID DYES----POLYAMIDE--- 80-90--------------5.0-- 20.0
 BASIC DYES---- ACRYLIC--------- 95-100-------0.0 – 5.0
 DIRECT DYES --- CELLULOSE---85 - 99-------1.0 – 15.0
 REACTIVE DYES -CELLULOSE-50.0- 85.0----15.0– 50.0
 SULPHUR DYES-- CELLULOSE--60.0- 90.0---10.0-- 40.0
 DISPERSE DYES --- PES----------90.0–100.0----0.0 –10.0
 METAL COMPLEX --- WOOL-------90 – 98 -------2.0
WATER FREE DYEING (SUPERCRITICAL FLUID DYEING):
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Uses carbon dioxide as the fluid medium on disperse-dyed
synthetics, eliminating aqueous effluent.
ECO- FRIENDLY EFFLUENT TREATMENT METHOD (BIO
TECHNOLGY):
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Combined biological system with electron- beam or advanced
oxidation process (AOP) method or Reverse Osmosis (RO).
SCHEMATIC PROCESS FLOW DIAGRAM OF ELOECTRON
BEAM METHOD COMBINATION WITH BIOLOGICAL SYSTEM
ETP
CLEANER PRODUCTION (CP) IN THE TEXTILE WET
PROCESSING
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For sustainable eco-friendly textile processing ,cleaner
production in each stage of specially textile wet processing is
must. Cleaner production includes:
Steam trap maintenance
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Insulation of un insulated steam and condensate return
pipelines
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Insulation of steam valves, tanks, pumps etc.
Re-use flash steam
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Using boiler economizer
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Insulated hot water tank with dyeing machine.
CLEANER PRODUCTION (CP) IN THE TEXTILE WET
PROCESSING
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Condensate recovery
Following right first time (RFT) dyeing method concept.
Use multi functional concentrated chemicals and high
exhaustion rate dyes reduces effluent problems.
Huge water savings – by adopting eliminate water leaks in
taps and pipes, use rain water, closed cooling system,
continuous dyeing, digital printing, co2 dyeing, reduce
washing and rinsing process cycles,
Reuse water drained out of steam condensates
Minimize washing and rinsing (overflow) operations
CLEANER PRODUCTION IN THE TEXTILE WET
PROCESSING
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Reuse of the first wash water from solution preparation tanks
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Restrain hose pipe use and create a central cut sample washing place.
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Insulate steam pipes
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Optimize operation of air compressors and chilling plants
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Use transparent roofs
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Reduce spillage of chemicals
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Use of magnetic device for soft water in boiler.
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Recover and re- use of waste heat ( using heat exchanger)
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Co-generation/ tri generation system where ever feasible.
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Using frequency inverter, peak load management, servo motor where
ever applicable, electronic ballast, energy saving lights,
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Increase fabric to water ratio to 1:6 or even less.
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Automatic boiler blow down mechanism
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Recovery & re-use of sodium sulfate using zero discharge etp
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Improve process control stages to avoid reprocessing
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Improve trial recipe in laboratory
CLEANER PRODUCTION IN THE TEXTILE WET
PROCESSING
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Improve process control stages to avoid reprocessing
Improve trial recipe in laboratory
Use of magnetic device for soft water in boiler.
Recover and re- use of waste heat ( using heat exchanger)
Co-generation/ tri generation system where ever feasible.
Using frequency inverter, peak load management, servo
motor where ever applicable, electronic ballast, energy
saving lights,
Increase fabric to water ratio to 1:6 or even less.
Automatic boiler blow down mechanism
Recovery & re-use of sodium sulfate using zero discharge etp
Improve process control stages to avoid reprocessing
Improve trial recipe in laboratory
STAGE 4: GARMENT MANUFACTURING
CONTRIBUTORS TO CARBON FOOTPRINT
 Many processes are involved in garment manufacturing and
pollution occurs in each and every stage.
1. In designing department making of prototypes produces
garbage’s like fabric scraps, pattern papers stationary items,
etc.
2. Production department undertakes spreading, cutting and
sewing responsibility. This department generates large
amount of waste in form of cardboard boxes, labels, tapes,
thread cones, stickers and fabric scraps
CONTRIBUTORS TO CARBON FOOTPRINT
3. Finishing department contributes to pollution while the fabric
goes various processes like washing, pressing, stain removal,
inspection, folding and packing. This consumes water and
also some chemicals such as detergents, liquid soap,
acetone, amyl, etc. Which are used in washing and stain
removal and garbages also produced in packing of materials.
4. Miscellaneous sections include computerised embroidery
section, effluent treatment plant, kitchen, canteen, mess and
general maintenance which also contribute in pollution.
DEPARTMENTS
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ADMINISTRATIVE
DEPARTMENTS
DESIGN & LINE DEVELOPMENT
DEPERTMENTS
CONTRIBUTIONS TO
POLLUTIONS
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Stationary waste, packing waste,
etc
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Packing waste, fabric waste,
paper pattern waste, etc
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yarn waste, packing waste,
threads, tapes, fusing rolls, fabric
scraps, ploy bags and stickers.
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Packing waste, chemicals
contributing to high bod/cod
levels in waste water.
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Packing waste, fabric scraps and
fuel
PRODUCTION DEPARTMENT
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FINISHING DEPARTMENT
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MISCELLANEOUS DEPARTMENT
ECO-FRIENDLY OR GREEN SOLUTIONS
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Various elements that are used in design i.E, colour, texture,
fasteners, fabrics, etc, the components of these should be
maintained as a ready data bank.
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Biodegradable trims should be preferred against synthetic trims
e.G., Natural buttons made up of peral, wood, shell, leather,
porcelain and bone.
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Plastic and metal buttons may be avoided.
Avoid use of fusible interfacings, which incorporate solvent
treated adhesives as solvents like formaldehyde have been
classified as unsafe for the environment as per standard given
by OEKO-TEX 100.
* Use of materials such as heavy metals like chrome, lead, nickel
used as fasteners like zippers and buttons are considered
unfriendly to environment.
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Use of large baler bags for storage or supplies especially at fabric
store where the fabric is stored in individual poly bags.
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CAD & CAM system can be used to gain optimum fabric Utilization.
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Installation of led’s (9w) at the needle points of sewing machines will
help to reduce the overall requirements of tube lights in the stitching
section.
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Regular maintenance, lubrication and upkeep of the machine using
white oil Mobil oil will result in improvement in efficiency of the machine.
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Usage of eco-friendly lubricants and stain removers, which are free
from chlorinated solvents.
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Prefer using of eco friendly hang tags that can be hung to the garment
by thread rather than using plastic staple or string.
* Apparel can be packaged in bio-degradable pvc-free packaging and in
100% recycled cardboard boxes.
STEP 5: TRANSPORTATION AND DISTRIBUTION
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CONTRIBUTION TO POLLUTION
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Some forms of transportation have more emissions
than the others for e.g. Transporting one tonne of goods
over a distance of 100 km emits 0.7 kg of CO2 by ship,
or 158.0 kg by air.
ECO-FRIENDLY OR GREEN SOLUTIONS
 Use the bus or train rather than car for transporting
goods and for travelling purpose.
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Consider cleaner fuels like ethanol e10 or Bio-diesel
which reduces CO2 emission significant amount.
STAGE 6: USE OF TEXTILE GOODS AND DISPOSAL
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CONTRIBUTORS TO CARBON FOOTPRINT
More than last two decades clothing has become increasingly
affordable for everyone. Retailers and brands have
capitalized on this affordability by moving away from summer
and winter collection to fresh collections more than last two
decades clothing has become increasingly affordable for
everyone.
ECO-FRIENDLY OR GREEN SOLUTIONS
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Recycle as much as possible. For example, old fabrics can
be used to make wipes or to make quilts, appliqué work.

Cellulosic waste fabric can be recycled for making handmade
paper.
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ENVIRONMENTAL SUSTAINABILITY

Need to believe in environmental sustainability
Implementing incremental steps in supply chain process to
accomplish.
Need to be aware about the social, economical and ecological
benefits of environmentally sustainable product development
processes.
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CONCLUSION:
The concept of “eco-friendly designing” products from start to
finish has come about. It involves considering the ecological
dimension of the entire production process, from the fibre to the
finished product, including its manufacturing processes, but
also its packaging and labeling, right the way through to
recycling & reuse the product at the end of its period following
3R concept.
So sustainable green trends in processing of textiles are:
Maintaining of high & consistent quality product in cost
effective manner.
Improved functionality
Lower generation of aqueous waste and off- gases
Minimum use or reuse of water and chemicals
Overall environment friendliness.
Reduce water and energy consumption during preparation,
coloration and finishing (CP).
Improve process efficiency
-Reduce exposure to hazardous chemicals
QUESTIONS AND ANSWERS ???